V. vinifera germplasm. Considering that stilbenes represent the most important class of phytoalexins in the Vitaceae, the constitutive expression and transcriptional activation of all the functional members of the stilbene synthase gene family were analysed in a group of nine grapevine genotypes following artificial infection with the oomycete Plasmopara viticola, the causal agent of the disease. In addition, in the same genotypes we analyzed the expression of genes encoding for two transcription factors involved in the transcriptional regulation of the stilbene synthase genes, namely VvMYB14 and VvMYB15, and of genes encoding for chalcone synthases.To limit the impact of the downy mildew disease of grapevine and reduce the need to recur to chemical treatments, an effective strategy might be recovering adaptive resistance traits in both cultivated and wild V. vinifera genotypes. The constitutive expression of the stilbene synthase genes as well as the extent of their transcriptional activation following P. viticola inoculation appeared to be inversely related to the proneness to develop disease symptoms upon infection. In a specular manner, following P. viticola inoculation all the chalcone synthase genes were up-regulated in the susceptible grapevine genotypes and down-regulated in the resistant ones. The infection brought by P. viticola appeared to elicit a co-ordinated and sequential transcriptional activation of distinct stilbene synthase genes subsets, each of which may be regulated by a distinct and specific MYB transcription factor.Downy mildew incidence and severity ranged from nihil to high in the grapevine genotypes considered, being low to moderate in a subgroup of V. vinifera germplasm. During the early stages of P. viticola infection, an antagonistic interaction between flavonol and stilbene biosynthesis might occur, whose outcome might determine the subsequent extent of disease symptoms. Further studies are needed to decipher the possible regulatory mechanisms involved in the antagonistic crosstalk between these two metabolic pathways in resistant and susceptible genotypes in response to P. viticola.The present results suggest that the induction of stilbene biosynthesis may contribute to the basal immunity against the downy mildew of grapevine, thus representing an adaptive resistance trait to recover, in both cultivated and wild  Vitis vinifera L.) is one of the most extensively cultivated plant, whose economic importance is witnessed by an almost seven and a half million Ha coverage worldwide , except that the peak of transcripts accumulation occurred earlier, i.e. at 16 hpi instead of at 24 hpi. Similar to the aforementioned B-STS genes, the initial accumulation of VvMYB14 transcripts (16 hpi) was significantly higher in SOL and ISA , intermediate in the two V. vinifera varieties ROS and ROM, as well as and in the SYL accession (about from 5 to 7 times higher than at 0 hpi) and comparatively lower in the remaining four V. vinifera varieties, i.e. CHA, TRE, CAN and ALE  until 72 hpi. Similar to VvMYB14 (see above), examining the VvMYB15 time profile allowed to identify three groups of genotypes, which can be distinguished among each other on the basis of the amount of the transcripts accumulated in response to PV. The first group included SOL and ISA hybrids, which showed the highest levels of accumulation of transcripts during the different stages of infection . The second group, represented by the V. vinifera varieties ROM and ROS and by the SYL accession, showed an intermediate accumulation of transcripts (approximately 6–7 times higher at 72 hpi than at 0 dpi). Finally, the third group included the remaining four V. vinifera varieties, namely CHA, TRE, CAN and ALE, in which the level of induction of VvMYB15 in response to PV was very low, comparatively speaking, being approximately 2–3 times higher at 72 hpi than at 0 hpi .No change in the temporal expression of V. vinifera genome (see above), VvCHS4 and VvCHS5 were not considered further here, because the level of their transcripts was very low or even null in the plant material under study (data not shown).Of the five genes coding for CHS identified in the VvCHS1, VvCHS2, and VvCHS3 genes. Significant differences were found in the constitutive expression of VvCHS genes among the grapevine genotypes considered  onwards, reaching their maximum at 72 hpi .No change in the temporal expression of V. vinifera germplasm is considered to be highly susceptible to downy mildew , resulting from multiple backcrossing among American species, V. amurensis and V. vinifera [Five arieties . The fivarieties , 16. Furvinifera , 20, 39.vinifera , both of− 2 s− 1. During growth, the plants were regularly watered.Two year-old potted plants of each grapevine genotype obtained from woody cuttings were used for the PV inoculation test under controlled conditions. The plants, each with three shoots, were grown in 6.5 L pots filled with a 2:1 mixture of commercial peat and pumice in a greenhouse at 22 ± 2 °C and 75 ± 5% relative air humidity, under a 16 h photoperiod whit natural daylight supplemented with high pressure metal halide lamps . The supplemental system was applied when photosyntetically active radiation dropped below a photosynthetic flux density of 900 μmol m5 PV zoosporangia mL− 1 onto the abaxial leaf surface. The inoculum was obtained from naturally infected plants showing downy mildew symptoms and maintained on the susceptible grape variety ‘Malvasia del Lazio’. Fifteen mock-inoculated plants for each genotype were obtained by spraying the leaves with distilled water only. Then, the mock-inoculated plants were kept isolated from the PV-inoculated ones and grown under identical environmental conditions.At the ten developed leaf stage, fifteen plants for each genotype were inoculated by spraying an aqueous suspension of 1 × 10p ≤ 0.05). Percentages were transformed to arcsine-square root values before analysis.The degree of resistance to PV of the nine grapevine genotypes was evaluated 7 days after inoculation . For each grapevine genotype, all the PV inoculated plants were used for measuring both disease incidence, which was expressed as the percent of symptomatic leaves over the total leaves, and disease severity, i.e. the percent of symptomatic leaf surface over the total leaf surface, which has been calculated according to the method proposed by Cadle-Davidson . The staV. vinifera genome view page.The sequences of the genes of interest were obtained from the NCBI  Reference Sequence database, which provides, for each species whose genome has been sequenced, a comprehensive, non-redundant, well-annotated set of sequences (RefSeq), including genomic DNA, transcripts, and proteins. The Reference Sequences of genes coding for STS and CHS synthases were recognized using two different strategies. First, the available grapevine STS and CHS cDNA sequences , 32, 59 The Reference Sequences of the two transcription factors VvMYB14 and VvMYB15 were identified by using the known sequences of the genes corresponding to the identifiers VIT_07s0005g03340 and VIT_05s0049g01020 [The respective NCBI mRNA and RefSeq protein sequences were retrieved for each identified gene , SAND protein family (VvSAND), glyceraldehyde-3-phosphate dehydrogenase (VvGAPDH), 60S ribosomal protein L18 (Vv60SRP), Actin7 (VvACT7), ubiquinol-cytochrome c reductase complex chaperone (VvUQCC), and V-type proton ATPase 16 kDa proteolipid subunit (VvVATP16)  calculated for standard curves higher than 0.995 were selected for expression analysis of the target and references genes.Specific primer pairs were designed for both target and reference genes  and ΔCt is the difference between the sample with the lowest Ct from the dataset and the Ct value of the sample in question. Only in the case of the comparison of the relative expression levels of selected members of the three phylogenetic groups of VvSTS gene family in the leaves of the nine grapevine genotypes collected before inoculation with P. viticola .The expression stability of the seven candidate reference genes  identified in the National Center for Biotechnology Information (NCBI) database. Table S2. List of primer pairs used in the present study for expression analysis of the Vitis vinifera stilbene synthase (VvSTS) genes. Table S3.Vitis vinifera gene sequences coding for chalcone synthase (VvCHS) identified in the NCBI database and used for the synthesis of oligonucleotides for expression analysis. Table S4.Vitis vinifera gene sequences coding for VvMYB14 and VvMYB15 transcription factors that specifically interact with the stilbene synthase promoter, identified in the NCBI database and used in the synthesis of oligonucleotides for expression analysis. Table S5.Vitis vinifera gene sequences coding for candidate reference genes identified in the NCBI database and used for the synthesis of oligonucleotides for the normalization of expression data in qRT-PCR analyses. (DOCX 30 kb)Additional file 2:Table S6. Statistical evaluation of the differences (one-way ANOVA followed by Tukey test) among the relative expression levels of stilbene synthase (VvSTS) genes in the leaves of nine different grapevine genotypes  after 0, 16, 24, 48, and 72 h from inoculation  with Plasmopara viticola. For each of the stilbene synthase gene, the upper panel shows the statistical differences of the mean ± SD among the five sampling times for each grapevine genotype; the lower panel shows the statistical differences of the mean ± SD among the nine grapevine genotypes at each sampling time. Different letters denote statistically significant differences at p < 0.01; n.s., not statistically significant at the chosen probability threshold. (DOCX 59 kb)Additional file 3:Table S7. Statistical evaluation of the differences (one-way ANOVA followed by Tukey test) among the relative expression levels of MYB transcription factors genes (VvMYB14 and VvMYB15) in the leaves of nine different Vitis vinifera genotypes  after 0, 16, 24, 48, and 72 h from inoculation  with Plasmopara viticola. For each of the MYB transcription factors genes, the upper panel shows the statistical differences of the mean ± SD among the five sampling times for each grapevine genotype; the lower panel shows the statistical differences of the mean ± SD among the nine grapevine genotypes at each sampling time. Different letters denote statistically significant differences at p < 0.01; n.s., not statistically significant at the chosen probability threshold. Table S8. Statistical evaluation of the differences (one-way ANOVA followed by Tukey test) among the relative expression levels of chalcone synthase genes (VvCHS1–3) in the leaves of nine different grapevine genotypes  after 0, 16, 24, 48, and 72 h from inoculation  with Plasmopara viticola. For each of the chalcone synthase gene, the upper panel shows the statistical differences of the mean ± SD among the five sampling times for each grapevine genotype; the lower panel shows the statistical differences of the mean ± SD among the nine grapevine genotypes at each sampling time. Different letters denote statistically significant differences at p < 0.01; n.s., not statistically significant at the chosen probability threshold. (DOCX 28 kb)Additional file 4:Figure S1. Leaves of the grapevine hybrid Solaris showing hypersensitive reaction seven days after inoculation with Plasmopara viticola. (TIFF 2066 kb)Additional file 5:Figure S2. Heat maps of the relative expression levels of the whole set of the Vitis vinifera stilbene synthase genes (VvSTS) in the leaves of the nine grapevine genotypes of Fig. Plasmopara viticola. The letter denoting the phylogenetic group to which each gene belongs is given in parentheses. For each gene, relative expression levels were calculated by setting a value of 1 for the lowest value among the nine genotypes in each of the five time points considered. Normalization and sample replication as in Fig.


Vallisneria natans grown at various water depths simulating different light availability, we measured variations in 20 traits for females and 19 traits for males  including morphology, reproductive traits and photosynthesis. We investigated sex-specific plastic responses and variation of sexual dimorphism in response to water depth change. Females displayed much greater leaf length, vegetative biomass and resource allocation to reproduction than males at all depths, whereas spathe number and gamete production per spathe displayed reverse pattern. Besides most traits in each sex  showing striking phenotypic plasticity, the degree of sexual dimorphism increased significantly for total biomass and reproductive investment, but decreased for leaf length, spathe number and flowering ramet percentage in low light and deep water. Females varied more than males in leaf length, total biomass, reproductive investment, length and biomass of reproductive organs and rate of photosynthesis in response to decreased underwater light availability, suggesting that female has greater plasticity than male. These findings illustrated considerable plasticity in the degree of sexual dimorphism in a variety of vegetative and reproductive traits across different environments driven by the contrasting reproductive functions of the sexes in relation to pollen and seed dispersal. Females of V. natans responded more plastically than males to low light conditions resulted from water depth variation in either aboveground vegetative growth or reproduction. This study provides novel insight into adaptive strategies of submerged dioecious macrophytes to survive and increase fitness in freshwater habitats.Sexual dimorphism in vegetative and reproductive traits is associated with contrasting strategies of males and females for response to varied environmental conditions, causing sex-specific reproduction success and consequently long-distance dispersal and colonization. Aquatic plants usually exhibit rich phenotypic plasticity and great diversity in reproductive systems, but the influence of aquatic conditions on the plasticity of sexual dimorphism has received less attention. Using a common garden experiment with dioecious submerged plant  Buchloe dactyloides . Especially, we want to answer these questions: (1) what is the magnitude of sexual dimorphism in V. natans across 16 common traits?; (2) do sexual dimorphisms plastically vary with increasing water depth?; (3) do adaptive strategies  to reduced light availability vary between sexes?In this study, the overall aim was to determine the magnitude of sexual dimorphism in a submerged dioecious macrophyte and test how the sexual dimorphism is affected by change in resources. Given the variations in sexual strategies in response to environmental change, we hypothesize that significant sexual dimorphism exists in the widespread submerged macrophyte Vallisneria natans (Lour.) Hara (Hydrocharitaceae), a submerged dioecious macrophyte with a wide geographical range, is a dominant native species in many freshwater habitats in China. It is frequently, though not always, annual species  and then preserved at 4°C.In November 2012, 30 intact and mature fruits were randomly sampled from 30 females  in our experimental population of –1, TP: 0.034 ± 0.005 mg⋅L–1, mean ± SE, n = 3) with a water depth gradient of 0.3, 0.8, and 1.3 m, representing the shallow, moderate and deep water, respectively. Finally, there were 600 plants in each water depth treatment (20 plants from each 30 families). The water level of the pool was maintained at the highest level. The light intensity at water surface and in the water column  were 1772.4 ± 195.0, 939.2 ± 66.7, 537.8 ± 35.9, and 275.3 ± 18.3 μmol⋅m–2⋅s–1 , respectively, at 14:00 on sunny days in mid August, measured by a UWQ-192 sensor . The percentage of light availability in relation to incident light at 0.3, 0.8, and 1.3 m was 53.0, 30.3, and 15.5%, respectively. The pH and temperature in the water column were recorded at 14:00 on sunny days in mid August using a Hydrolab DS5X multi-parameter water quality analyzer . Along water depth from shallow to deep, the pH  is 7.34 ± 0.158, 7.30 ± 0.153, and 7.09 ± 0.166, and the water temperature  is 24.4 ± 0.2, 23.8 ± 0.5, and 23.4 ± 0.4°C, respectively.In March 2013, 120 seeds of each family were germinated in plastic jars (12-cm diameter and 12-cm height) covered by 2-cm-deep sterile substrate (mixture of mud and lake sand at 4:1 volume ratio). The jars were filled with water and placed under constant room temperature at 25°C with a 12 h:12 h light cycle. In early May 2013, when the seedlings produced three or four leaves, we randomly transplanted 60 seedlings of each family into plastic pots  filled with 8-cm-deep sterile substrate. Before transplantation, plant height of each seedling was measured. In total, 1800 pots were placed randomly in the outdoor experimental pool full of tap water . Finally, the experiment involved three water depth treatments, two sex treatments, 30 families and three replicates per treatment . Each plant was hand-washed free of sediment and epiphytic aquatic organisms. We counted both the total and flowering ramet numbers to calculate the percentage of flowering ramets of each plant. Leaf number per flowering ramet of each plant was measured as the mean of three randomly selected flowering ramets (including the ortet) from the same plant, as well as number of spathes and fruits per flowering ramet. The total numbers of spathes per male plant and fruits per female plant were also recorded. We randomly selected three flowering ramets (including the ortet) of each plant to measure the length and width of the longest intact leaf. Spathe length and flower number per male spathe were measured based on three non-dehiscent, mature spathes from each male. Mean ovule number per female spathe was measured based on three non-dehiscent female spathes from each female. Mean fruit length and seed number per fruit were measured based on three mature fruits from each female.Every plant was partitioned into belowground structures (including roots and stolons), leaves, and sexual reproductive structures . The plant parts were dried to constant weight at 80°C and weighed. Considering that some male spathes had withered at the time when the plants were harvested, we randomly sampled 5–10 non-dehiscent, mature male spathes from each male plant within each depth and weighed the mass per spathe. Then we multiplied the mean values of spathe mass obtained at each water depth by the total number of spathes per male to give an estimate of the biomass of sexual reproductive structures of male plants for each water depth. Similarly, we estimated the biomass of mature fruits with intact peduncles of female plants for each water depth. Biomass allocation to reproduction, leaves and belowground structures was determined by dividing the mass of each by the total biomass of the plant. In total, 19 and 20 traits (including photosynthesis) were measured for male and female individuals, respectively (16 was common in both sexes).Five never-transplanted seedlings were randomly selected from each family  to transplant into pots (the same methods as above). The pots were then placed in the greenhouse pool of the Fudan University . The growth status of each plant was checked at the beginning of July. From each family, the individual with the most ramets was selected (minimum of nine ramets), and six ramets of similar size were selected to be transplanted into new pots after measuring the length of the longest leaf. Subsequently, three pots of each family were placed at water depths of 0.3 and 1.3 m in the outdoor experimental pool . Finally, there were two water depth treatments, two sex treatments, 30 families  and three replicates per treatment . The pots at the water depth of 1.3 m were connected by a nylon string to lift them to facilitate the measurement of the plants at any time. A hundred days after transplantation all plants were harvested. Five vegetative traits, six reproductive traits and photosynthetic rate were measured see .V. natans (late August to early September), an intact mature leaf was collected from 15 randomly selected males and 15 randomly selected females in each of the water depth treatments . A segment of each leaf  was cut and incubated in a glass-stoppered tube  with pool water to measure light saturated photosynthesis under ambient temperature conditions. Then the tubes were placed under a 3200-lx (∼690 μmol m–2 s–1) fluorescent tube, with all leaves parallel to the lamp. Another eight glass tubes filled with pool water but without leaf fragment were served as control. The initial dissolved oxygen  was measured using JPM-607A electronic dissolved oxygen analyzer , and then all samples, including the controls, were placed under the fluorescent tube . Tubes were moved regularly to make sure that the boundary layer did not cause CO2 to become limiting for the plant’s photosynthesis. After 4 h of continuous exposure to irradiation with a constant temperature of 25°C, the leaf fragments were removed. Then the electrode of the dissolved oxygen analyzer was quickly inserted into the glass tube to measure the dissolved oxygen (DO4h) of the water sample. The change in dissolved oxygen (ΔDO) of each leaf sample over 4 h was obtained by subtracting the average DO0 of the eight control samples. The photosynthetic rate (mg⋅L–1 g–1 h–1) of each leaf sample was obtained by dividing ΔDO by 4 h and 0.3 g (fresh weight of each leaf sample used in the incubation).Photosynthesis was measured both in the first and the second experiment. During the vigorous growth period of SDI) is SDI = Log (M: F), where M and F were values of male and female traits, respectively; and the significance of SDI was analyzed by χ2 tests (to determine whether it is significantly biased toward zero). The differences among water depths and between sexes were compared by a Tukey honestly significant difference (HSD) test procedure (α < 0.05). Two-way ANOVA was performed with depth and sex as independent variables and all the traits in experiment II as dependent variables. If there is an interaction effect, males and females change differently in the given trait with depth. All of the statistical analyses were performed using SPSS 19.0 software .In this study, all of 23 detected phenotypic traits in experiment I were analyzed using one-way ANOVA for sex, water depth, and family. For the effect of depth and family, we analyzed the male and female’s traits separately. For the nine shared traits , the equation that we used for calculating sexual dichotomous index , photosynthetic rate, spathe number per flowering ramet, as well as leaf number per flowering ramet for both sexes increased significantly with increasing water depth . In femaBoth the percentage of flowering ramets and spathe number were male-biased, and sexual differences in both traits decreased with depth ; trait 2The significant interactive effect of sex and water depth for 6 out of 12 life history traits that we tested for 17 male and 13 female genotypes indicated that there was substantial intersexual difference in the responses of adaptive traits to water depth change . FemalesV. natans displayed considerable plasticity in growth and reproductive traits in response to water depth change. Although phenotypic plasticity has been the focus of many previous studies on submerged macrophytes . Many studies have found that females expended proportionally more of their resources on reproduction per reproductive bout than their male counterparts , includimericana  and V. spinulosa ,b. In copinulosa . AnotherV. natans, the timing of investment in growth vs. reproduction within a growing season varied between sexes  and light reception  in females were greater than in males, in spite of the fact that overall fraction of biomass devoted to reproductive organs was much greater in females than males. This suggests that females have a mechanism to compensate by producing more biomass for the extra investment in reproduction. In dioecious en sexes . Male gren sexes , and thien sexes . In conten sexes .V. natans plants photosynthesized more at higher depths suggests that plants adjust their photosynthetic physiological responses to lower light levels (deep water) to enhance light capturing ability, and this combined with leaf elongation toward the surface of water as a way to alleviate low light stress. Submerged macrophytes growing under low light stress usually increase the light capturing ability of plant leaves   . Also instrategy . Thus, oV. natans males and females were responsive to the increase of water depth. Both the number of seeds  and male flowers  that produced per unit of total plant biomass decreased drastically with increasing water depth (P < 0.001). This implies a reduction in resources consumed to produce a male flower or a seed at shallower depths. Consistent with our predictions, females had a greater decrease in reproductive allocation than males in response to low light conditions in deep water. First, although light capturing ability (photosynthetic rate) of leaves in females increased more than that in males in the low light, deep water environment as a result of reduced photoinhibition, female reproduction incurs a higher cost than males. This is because flowering in females requires substantial additional investment in flowering bearing structures (very long peduncles) to support flowers to the water surface in deep water  per spathe (or seed number per fruit) did not change with water depth. This response may be due to the need for females to accumulate more pectin and chlorophyll to facilitate fruit photosynthesis and seed maturation in low light, deep water environment, thereby reducing the vegetative burden borne by leaves. There are numerous studies reporting the contribution of fruits to the maintenance their own carbon . By contV. natans, in terms of vegetative biomass, were not greatly affected by water depth. However, reduced light availability resulted in a greater increase in leaf length, total biomass and photosynthetic rate in females than in males.Contrary to our predictions that the sexual dimorphism in vegetative investment increases in more stressful environments, size differences in V. natans to water depth change implies that growth and reproduction of male and female individuals can be affected differently by flooding and water level fluctuations in freshwater habitats, producing variations in the degree of sexual dimorphism. Consequently, long-distance dispersal and colonization of submerged dioecious macrophytes may be impacted by environmental variations in aquatic ecosystems. More studies across aquatic dioecious species are required to make general conclusions on the effects of altered environmental conditions on growth and reproduction of aquatic vegetation via adaptive strategies, e.g., plasticity in sexual dimorphism.Females should maximize allocation to aboveground growth under conditions of light attenuation more than should males, in combination with a stronger reduction of allocation to reproductive tissues, because carbon acquisition is more critical for female reproduction (higher fecundity) . The effYZ and ZS designed the research. YZ conducted the experiments. LL and YZ conducted the statistical analysis. LL wrote the manuscript. All authors commented on and approved the final draft of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Arabidopsis thaliana, and agriculturally important monocotyledonous cereal species, such as Hordeum vulgare (barley). However, the amount of variation in ovule development among genotypes of a single species, and its functional significance, remains unclear. To address this, wholemount clearing was used to examine the details of ovule development in barley. Nine sporophytic and gametophytic features were examined at ovule maturity in a panel of 150 European two-row spring barley genotypes, and compared with grain traits from the preceding and same generation. Correlations were identified between ovule traits and features of grain they produced, which in general highlighted a negative correlation between nucellus area, ovule area, and grain weight. We speculate that the amount of ovule tissue, particularly the size of the nucellus, may affect the timing of maternal resource allocation to the fertilized embryo sac, thereby influencing subsequent grain development.The ovule plays a critical role in cereal yield as it is the site of fertilization and the progenitor of the grain. The ovule primordium is generally comprised of three domains, the funiculus, chalaza, and nucellus, which give rise to distinct tissues including the integuments, nucellar projection, and embryo sac. The size and arrangement of these domains varies significantly between model eudicots, such as  Barley is a cereal that has sustained humans for thousands of years and remains a crop of key agricultural and economic importance . A largeTriticum aestivum) and maize , which contain multiple florets of which only the central floret is fertile. All of the organs and tissues required for self-fertilization and seed production are located within this floret. This includes a single ovule within a single ovary (pistil), which together comprise the female reproductive organs that give rise to and protect the bulk of the tissues within the grain. The number of mature florets has been linked to barley yield , while tea mays; . Thus, cArabidopsis  that undergoes meiosis to produce a tetrad of four reduced megaspores (megasporogenesis), one of which is selected to become the functional megaspore and initiate embryo sac development (megagametogenesis). In both barley and Arabidopsis the embryo sac consists of seven different cell types with discrete functions. The position of the egg apparatus, central cell, and antipodal cells are conserved, but the number of antipodal cells varies considerably from three in Arabidopsis to at least 30 in barley and other cereals  and differentiate to form the nucellar projection  compared to 176,697.89 µm2 (n = 457) in GH17  overnight, then dehydrated through an ethanol series  and placed into Hoyer’s solution as described in Pistils were fixed in FAA  software as described in https://cran.r-project.org/web/packages/corrplot/corrplot.pdf) in R with RStudio . Unless indicated otherwise, Pearson’s correlation coefficients and associated significance values are shown. Figures were assembled in Adobe Illustrator CC 2018 .Genotypic variance components were obtained from linear mixed models with a random genotypic effect and their significance was tested by model comparison with likelihood ratio tests where the halved P values were used as an approximation . Repeata™ SC4  at the University of Adelaide, following manufacturer’s instructions. Data were obtained from two generations of the same genotypes i.e. grain that was sown and collected in 2014 (“2014” grain), and grain that sown and collected in 2015 (“2015” grain). Ovule phenotypes were collected from plants that gave rise to the 2015 grain. In total, sufficient numbers and replicates of grain and ovule data were obtained for 73 genotypes.Grain traits were analyzed using a SeedCountNine distinct stages of barley ovule development were discernible in cleared floral tissue using DIC microscopy Figure 1Mature ovule morphology (Ov10) was measured in all 150 genotypes in terms of 2-dimensional area and 1-dimensional distances . Regiona2 and a standard deviation (SD) equating to approximately 22% variation in size. Ovule area and nucellus area were comparatively less variable, observed to be 174,421.2 ± 19,857.8 µm2 (11.4% SD) and 125,560.8 ± 13,408.7 µm2 (10.7% SD), respectively. Consistent with this, the transverse and longitudinal measurements of the embryo sac varied more than the transverse and longitudinal measurements of the ovule  than embryo sac area and ovule area . Meanwhile, both embryo sac area and ovule area were negatively correlated with nucellus proportion . This suggests that while an increase in nucellus area reliably leads to larger ovule area, excessive embryo sac growth may achieve a similar outcome but at the expense of the nucellus. Bigger ovules were also more likely to have thinner integuments, as all ovule traits were negatively associated with integument width, particularly ovule area and nucellus area, although the correlation was low .Pearson correlation analysis was used to assess if overall variation in ovule morphology is a result of coordinated development of all ovule tissues, or whether growth of one tissue is more important S4. Nucer = 0.82, p < 0.001) were closely positioned on the PCA plot in contrast to those for ovule transverse width and longitudinal height  plot . Grain samples were sorted to focus only on genotypes showing evidence of good fill and at least 50 grain in at least 2 replicates. After filtering, 73 genotypes remained for comparison between years and with ovule phenotypes . Despite being grown in glasshouses with similar environmental regimes, differences in sowing dates in 2014 and 2015 appeared to significantly impact fill; grain weight was 42.8 ± 0.99 in 2014 vs. 35.2 ± 0.56 in 2015 . This is perhaps unsurprising given the later sowing date. However, several correlations were identified across the 2 years. For example, grain weight showed a small but significant correlation , no correlation was observed between any embryo sac measurement and grain measurement.Grain traits were compared to ovule measurements from the same 73 genotypes S7. No st-test, p = 0.01; t-test, p = 0.008; These effects appeared to be even more prominent when considering phenotypic extremes  and CYP78A9 influence proliferation of integument cells and subsequently the cells of the seed coat, ultimately regulating ovule fertility and overall seed size (TaCYP78A5 (the wheat orthologue of KLU) was found to restrict seed coat cell proliferation and cause a 10% reduction in grain size  to MT.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor declared a past co-authorship with one of the authors [MT].


Populus cathayana) samples first underwent impregnation with alkali lignin solution and were then subjected to heat treatment at 140–180 °C for two hours. The results indicated that the modified wood showed excellent leaching resistance. The alkali lignin treatment improved surface hydrophobicity and compression strength, and decreased moisture and water uptake, thereby reducing the dimensional instability of modified wood. These changes became more pronounced as the heat-treating temperature increased. Scanning electron microscopy, confocal laser scanning microscopy, and Fourier transform infrared spectroscopy evidenced that a multiscale improvement of the alkali lignin occurred in the cell lumen and cell wall of wood fibers and vessels, with small alkali lignin molecules reacting with the wood matrix. This study paves the way for developing an effective modification approach for fast growing wood, as well as promoting the reuse of industrial lignin for high-value applications, and improves the sustainable development of the forestry industry.Chemical modification of wood with green modifiers is highly desirable for sustainable development. With the aim of enhancing the water resistance and dimensional stability of fast growing wood, modifications were conducted using renewable and toxicity-free industrial lignin combined with heat treatment. Poplar ( As the second richest polymer from biomass after cellulose, lignin is usually accepted as biomass waste in the pulping industry. The lack of use of lignin has led to a massive waste of resources and pulping emissions have become an issue of environmental concern . Only abLignin is regarded as a natural raw material that can modify or replace other materials because of its unique chemical structure and abundance in nature. Peng et al. found that polypropylene composites reinforced with alkali lignin showed higher surface hydrophobicity after a weathering treatment . DirectlThe problem may be solved by heat treatment. Studies have shown that lignin chemical reactivity increased during heat treatment, since a number of reactions including radical oxidation, molecular transposition, dehydrogenation, and polycondensation occurred, resulting in cross-links between lignin molecules ,7,8. DueThe objective of this study was to take industrial lignin as a modifier to enhance the water resistance and dimensional stability of fast growing wood. Heat treatment was introduced to facilitate a redistribution of the impregnated lignin and cross-links between it and wood matrix. The effects of this combined treatment, including water resistance and dimensional stability, were investigated. Morphological and chemical characteristics were analyzed by scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and Fourier transform infrared (FTIR) spectroscopy, with high expectation of multiscale modifying both the cell cavity and cell wall levels. Results from this study expand the application field and resolve the bottleneck for the use of fast growing wood, and enable the high-valued reuse of industrial lignin, therefore contributing to more environmentally friendly and sustainable development of the forestry industry.Populus cathayana), which belongs to the fast growing species, and is quite common in North China. The 20 × 20 × 20 mm3 (L × T × R) samples were oven-dried at 103 °C until they reached a constant weight m0 (g) (labelled as Control). Alkali lignin extracted from pulping black liquor , was purchased from Shan Feng Chemical Co., Ltd., Changzhou, China.The test species was Poplar (m1 (g) (labelled as AL). Finally, the AL samples were subjected to three temperatures of 140, 160, and 180 °C for 2 h , and the weight m2 (g) after heat treatment was recorded. The weight percent gain (WPG) for the impregnation treatment and mass loss (ML) for the heat treatment were evaluated according to the following equations:The alkali lignin particles were dispersed in 1,4-dioxane to the maximum concentration followed by filtration for later use. The samples were impregnated with alkali lignin solution using a vacuum-pressure process. In this study, the samples were subjected to a vacuum at −0.1 MPa for 30 min, then they were immersed in alkali lignin solution at 0.5 MPa for 1 h. After impregnation, the excess liquid in the wood surface was wiped with tissue paper and oven-dried at 103 °C to constant weight To characterize structural details and the alkali lignin location of the modified wood, transverse and tangential sections of the samples were placed in conductive glue and sputter-coated with gold. Then, the microstructure of the samples was observed by SEM  with a voltage of 15 KV.To further qualitatively and quantitively investigate the spatial distribution of alkali lignin within the samples, transverse sectional samples 10–20 μm thick from the microtome were subsequently inspected with a Leica TCS SP5 confocal microscope  with a krypton/argon laser emitting at wavelengths of 488 nm. The same gain setting (115) was used for the samples so the emission intensities could be directly compared in the images.–1 and 32 scans per sample in the 4000–400 cm–1 interval.To explore the changes in the functional groups in the wood after treatment, flour of the samples (100 mesh) was pressed into KBr pellets and tested by FTIR  with a resolution of 4 cmThe treated samples were tested for leaching resistance according to the E11-06 American Wood Protection Association (AWPA) standard. For each group, three replicates were leached in 300 mL of deionized water at 22–28 °C. The samples were completely submerged and stirred with a magnetic stir bar in flask bottles. The water was replaced after 6, 24, and 48 h, and thereafter at 48-h intervals. The leachability test lasted for 14 days, and the weights of the samples (dried at 103 °C) before and after the leaching treatment were recorded.All the samples were conditioned at 25 °C and 72% relative humidity (RH) to a constant mass before measurement. The time-dependent contact angles were measured according to sessile drop method by Dataphysics OCA20 contact angle analyzer . Data were gathered stochastically from three sites on the transverse section of every sample with each group containing three replicates. The dispense process was completed by an automatic microsyringe with approximately 3 μL of distilled water.2CO3, NaBr, and NaCl, respectively [w and αmax), and volumetric swelling rate (αVw and αVmax) of the samples were calculated from three replicates as follows:w represents the adsorption process; max refers to the absorption process; M0, nM, and nW are weights of over-dried samples and samples after n hours of adsorption and n hours of water absorption (g), respectively; L0, wL, and maxL are the tangential dimensions of over-dried samples and samples after n hours of adsorption and n hours of water immersion (mm), respectively; and V0, wV, and maxV are volumes of over-dried samples and samples after n hours of adsorption and n hours of water immersion (mm3).Water resistance and dimensional stability were tested according to Chinese standard GB/T 1934.1-2009 and GB/T 1934.2-2009, respectively. Oven-dried samples were exposed separately to 3 different RH of 45%, 55%, and 72% at 25 °C for adsorption. The 3 RH conditions were created by applying saturated salt solutions of Kectively . The remThe adsorption behavior of the modified samples was analyzed using the Hailwood–Horrobin (H–H) sorption model . Accordi−1 according to GB/T 1935-2009. Each group included 6 replicates in the tests. The axial compressive strength (σ) was calculated as follows:maxP is failure load (N), and b and t are the radial and tangential length of the samples (mm), respectively.The samples were conditioned over a NaCl saturated solution (75% RH) at 25 °C before mechanical tests. The axial compressive strength was determined with a universal mechanical machine  at a test speed of 1 mm·minAs listed in Brighter areas represent higher lignin concentration. As shown in –1. Generally, analysis of changes in wood chemical components by O–H stretching absorption bands and C–H absorption bands (around 2923 cm–1) is limited, which is due to the fact that the three main chemical components  of wood all contain hydroxyl and methylene moieties [Taking the Control, AL, and AL 180 °C as examples, –1 increased significantly compared with the Control. The peaks were assigned to aromatic conjugated C=O and benzene ring vibration respectively, which originated mainly from lignin [–1 (C=C stretching vibration) [–1 is the characteristic peak of Ar–O stretching or α- or β-aryl ether in lignin [–1 assigned to C=O stretching, attributed primarily to hemicellulose [From m lignin . Anotherbration)  also incn lignin ,22. The ellulose , showed –1 wave numbers were attributed to the functional groups of lignin, to quantitatively estimate the change in lignin content or lignin functional groups after treatment, the lignin index (LI) was calculated according to Equation (10) based on the intensity of the peak at 1049 cm–1, which corresponds to the oxygen-containing functional groups of cellulose in wood [I is band intensity.Because the 1263, 1427, 1507, 1632 cm in wood , usually1263, LI1427, and LI1507 of AL and AL 180 °C increased compared to the Control, again confirming the increase in the lignin content in treated wood. However, the values of LI1263, LI1427, and LI1507 of AL 180 °C were lower than those of AL, with an opposite trend for LI1632, which belongs to the aromatic conjugated C=O in lignin. This may be due to the degradation of alkali lignin after heat treatment (As shown in reatment , followeThe initial contact angle and change in contact angle with time for the samples is demonstrated in The 18/W calculated by the H–H sorption model is listed in The moisture adsorption rate of the samples was evaluated by taking the first derivative according to As shown in Compression strength values of the samples listed in In this study, we reported an effective, low cost, and sustainable modification method for fast growing wood. The samples modified by alkali lignin combined with heat treatment produced obvious improvement both in hydrophobic properties and dimensional stability, without adversely changing the mechanical properties of the wood. Based on a multiscale modification of the cell cavity as well as cell wall levels, a novel wood with enhanced performance can be used as a fully green product, which can be easily disposed of and used as an ecologically friendly material. Since most chemical modifications are often hindered by ecological drawbacks, such as lack of sustainability, ecoefficiency, and recyclability of the products, this process promotes the efficient and sustainable development of the forestry industry.


Aeluropus littoralis. The experiment was laid out in a completely random design with three replications. The expression of the main gene was normalized to the expression of the housekeeping gene actin. Two 259 and 187 bp fragments were amplified from plasma membrane H+-ATPase and actin genes using specific primers in polymerase chain reactions. The results indicated that higher concentrations of all three heavy metals declined the expression of plasma membrane H+-ATPase gene, whereas low concentrations changed the level of its transcript differently. A significant linear correlation was found between Ag concentrations of Aeluropus littoralis shoots and its external level; however, for Hg and Pb no correlations were observed. Root weight decreased when plants were grown at both concentrations of Ag and Hg but increased at both concentrations of Pb and NaCl. Maximum root weight was observed under lower levels of Pb, while maximum shoot weight was observed under lower levels of Hg. The greatest plant weight was obtained at low concentrations of Hg and Pb. Taken together these results show the regulation of plasma membrane H+-ATPase gene by heavy metals suggesting that Aeluropus littoralis can be regarded as a Phytoremediation accumulator of soils polluted with heavy metals.The present study was conducted to find the effect of three heavy metals, Ag, Hg and Pb on the expression level of a gene encoding plasma membrane H+-ATPase in  Heavy metals, such as lead, mercury, and silver, are a group of metals which have densities greater than 5 grams per cubic centimeter . The conSome metals such as Zn are essential while others such as Cd are not, but previousresearch shows that heavy metals are toxic at high concentrations anyway . StudiesWhen cells are exposed to heavy metals, plasma membrane (PM) is the first barrierto the movement of metal ions into the cytoplasm . Metals H+- ATPases are a major species of plasma membrane proteins that plays importantroles in various physiological activities of the plant like abiotic stress response. These proteins use the energy provided by ATP hydrolysis to transport protons out of the cell, generating an electrochemical gradient across the membrane , 11.Previous studies indicated that the expression pattern of various genes in differentorganisms changed after exposure to heavy metals , 13. SomAeluropus littoralis, is a diploid plant (2n = 2x = 16) with a relatively smallgenome of about 342 Mbp [A. littoralis to some heavymetals has been previously studied [As a rich genetic resource used for identifying new genes resistant to abiotic stress, Gouan,  342 Mbp . The bio studied , 20. Oth studied . It was  studied .A. littoralis and determine its relation with metal ion contents of the shoots under these heavy metals' stress.As of date, little research has been done to determine the expression pattern of the PM H+-ATPase gene under some heavy metal stress in some plants and to the authors' knowledge, no research has been carried out to study the expression level of this gene under Ag, Hg or Pb stress. Hence, in the present work we tried to analyze the expression pattern of a gene which encodes a PM H+-ATPase pump in Cultivation of plants and experimental design: A. littoralis seeds were collected from Maharlu Lake, south of Shiraz, surface sterilized by soaking in 1% (v/v) sodium hypochlorite for 20 min and rinsed three times with distilled water. In order to get more uniformly germinated seeds, they were placed in Petri dishes on two layers of filter paper moistened with 10 ml distilled water and incubated at 4°C for 72 h. Germinated seeds were planted in plastic pots filled with perlite and grown in a greenhouse under a16/18 h day/night cycle and 25/16°C day/night temperature. Plants were irrigated everythree days with 1/2 modified Hoagland solution . After t100 µl) of AgNO3, HgCl2, Pb(NO3)2 and 200 or 400 mM NaCl, separately. The experiments were carried out in a completely randomized design with 3 replicates.Measurement of plant heavy metal content: Heavy metal content was measured as previously described [escribed . Leaves RNA extraction, preparing cDNAs: Leaves were sampled 0, 6, 48 and 72 h after treatment, frozen in liquid nitrogen and stored at -80°C until used for RNA extraction. Total RNA was extracted from leaves using GF-1 Total RNA Extraction Kit . The quality of the extracted RNA was assessed by electrophoresis on 1% agarose gel. First-strand cDNAs were prepared from 1 µg total RNA by RevertAid M- MuLV reverse transcriptase  with oligo (dt) primer.PCR reactions: The expression pattern of PM H+-ATPase gene was investigated in the leaves by semiquantitative RT-PCR. The cDNAs were amplified by specific primers  procedures using SAS (version 9.3). Treatment means were separated by Duncan's multiple range test (P<0.05).The effects of different concentrations of various heavy metals and NaCl on shoot and root weight are shown in et al. (2005) who showed that lettuce growth was negatively affected by silver [Salvadora persica [Cynara cardunculus roots increased for plants growing in NaCl but not for those grown in KCl [A. littoralis, although it significantly increased the weight of roots in both levels  significantly affected the expression levels of PM H+-ATPase. The effect of high concentrations of Ag, Hg and Pb was similar, and all heavy metals in high external supply levels decreased the expression level of PM H+-ATPase -4, whereCucumis sativus, whereas the transcript level of the CsHA3 gene in plants treated withlow concentrations of Cd (10 µM) was similar to the control [ control .The expressions of the PM H+-ATPase gene in plants treated with low concentrations (50 µM) of all three heavy metals were significantly higher than plantstreated with high concentrations. Low concentrations of Ag caused the significant increment of PM H+-ATPase gene expression after 6, 48 or 72 h . On the Arabidopsis thaliana [AtPDR12, a gene encoding an ABC transporter in A. thaliana, increased in response to Pb treatment and that AtPDR12 contributes to the resistance ofArabidopsis to Pb [In low concentrations, the accumulation of PM H+-ATPase gene transcript in Pb- treated plants decreased and reached a minimum at 6 h but increased afterwards from 6 h to 72 h . It has thaliana . These sthaliana . Moreoveis to Pb . It can In the case of Hg, the expression level of PM H+-ATPase decreased in the shoots for a short time, increased after 48 h, and decreased again after 72 h . It has reported yet.Although many studies have shown changes in the gene expression of PM H+- ATPase in response to a variety of environmental factors, including drought, salt andmechanical stress , 34, to A. littoralis and that of the external supply level, while in the case of Hg and Pb no correlation was observed. The expression level of the PM H+-ATPase gene was changed by 50 µM Ag, Hg and Pb but decreased with high levels of these heavy metals.Taken together, the results showed that with the exception of Pb and Hg at low concentrations, heavy metals reduced the weight of plants, while NaCl increased fresh weight at both concentrations. The shoots of gouan did not accumulate heavy metals with similar efficiency. A significant linear correlation was found between the concentration of Ag in the shoots of A. littoralis can accumulate exceptional concentrations of Pb in its root without showing toxicity symptoms. Plant species, belonging to the accumulator class, have exhibited higher tolerance to excessive levels of Pb in the growth media [A. littoralis may be introduced as an accumulator for this metal.The results indicate that th media . Hence,


Five segregation distorted regions were found with four showing enrichment for S. bicolor alleles, suggesting possible selection during formation of this RIL population. A quantitative trait locus (QTL) study with this number of individuals, tripled relative to prior studies of this cross, provided resources, validated previous findings, and demonstrated improved power to detect plant height and flowering time related QTL relative to other published studies. An unexpected low correlation between flowering time and plant height permitted us to separate QTL for each trait and provide evidence against pleiotropy. Ten non- random syntenic regions conferring QTL for the same trait suggest that those QTL may represent alleles at genes functioning in the same manner since the 96 million year ago genome duplication that created these syntenic relationships, while syntenic regions conferring QTL for different trait may suggest sub-functionalization after duplication. Collectively, this study provides resources for marker-assisted breeding, as well as a framework for fine mapping and subsequent cloning of major genes for important traits such as plant height and flowering time in sorghum.We describe a genetic map with a total of 381 bins of 616 genotyping by sequencing (GBS)-based SNP markers in a F Sorghum bicolor is a model for plants that use C4 photosynthesis, improving carbon assimilation especially at high temperature, complementary to C3 model plants such as Oryza sativa. The sequenced ∼730 megabase sorghum genome (Saccharinae clade including Miscanthus and Saccharum (sugarcane).The most drought resistant of the world’s top five cereal crops, sorghum, contributes 26-29% of calories in the human diet in semi-arid areas of Africa (FAO), on some of the world’s most degraded soils and often with limited water inputs. A multi-purpose crop, sorghum has been traditionally used as grain and straw, and is also a promising crop for bioenergy production from starch, sugar, or cellulose on marginal lands with limited water and other resources , diverged from S. bicolor 1-2 million years ago , an invasive and weedy species formed by unintentional crossing of S. bicolor and S. propinquum  has brought new power to revealing allelic differences among individuals by detecting large numbers of single nucleotide polymorphisms (SNP). While it is neither necessary nor practical (yet) to generate whole genome sequences for every individual in a designed mapping population, reduced representation library (RRL) sequencing has been widely utilized and proved to be both a cost and labor efficient tool for genotyping  population of 393 individuals derived from two divergent 1 plant from S. bicolor BTx623 and IS3620C as described (The mapping population is comprised of 399 F7-8 RILs derived by selfing a single FLeaf samples of the RIL population was frozen at -80 C and lyophilized for 48 hr. Genomic DNA was extracted from the lyophilized leaf sample based on Our GBS platform is a slightly modified version of Multiplex Shotgun Genotyping (MSG) (Sorghum bicolor (2) is greater than 0.9, deriving consensus genotypes in a manner minimizing missing genotypes. SNPs are further merged if the Pearson’s correlation between them is larger than 0.95; (c) For bi-parental populations, the missing genotype of one parental line can be imputed by offspring genotypes if the genotype of the other parent at the locus is known. After these filtering steps, SNP data are used for genetic mapping.SNP ‘calling’ (inference) was based on the reference genome sequence of de novo and reference based methods, i.e., the physical positions of SNPs. The ‘ripple’ function was used to assist and validate ordering of the genetic map.A genetic map using 616 SNP markers was created using R/qtl  for each marker with both raw and imputed data as an indicator for segregation distortion. To account for multiple comparisons across the genome, the significance level was adjusted using Bonferroni correction. The imputed data were generated using R/qtl (PH), the overall length of a plant; base to flag length (BTF), the length from the base of the plant to the flag leaf; flag to rachis length (FTR), the length from the flag leaf to rachis ; number of nodes (ND); and days to flowering (FL), the average days to flowering for the first five plants for each genotype.QTL were detected for five traits of interest: plant height (We combined the phenotypic data using Best Linear Unbiased Prediction (BLUP) by treating individuals, years, replications nested within years and the interactions between individuals and years as random, since heritability for the traits of interest were relatively high. In 2011, we observed and recorded a soil type change within the experimental fields, which was treated as a covariate to calculate BLUP values for each genotype. A genome scan with the interval mapping method was first conducted with 1000 permutation tests; the putative QTL were then selected and fit into a multiple QTL model. We added additional QTL to the model if they exceeded the threshold of 3.0 after fixing the effect of QTL included in the first genome scan. A multiple QTL model (MQM) was used to determine the final model for each trait. All statistical analyses and QTL mapping used R  and the PH, BTF, FTR, ND and FL), then the chromosome number and a decimal number to differentiate multiple QTL on the same chromosome.QTL nomenclature used a system that was previously described in rice  with varying SNP numbers in each bin (File S3). The bin map collectively spans a genetic distance of 1404.8 cM, with average spacing of 3.8 cM between loci and the largest gap being 27.6 cM on chromosome 5  at the peak marker, S1_14765342. Segregation distortion occurs when the segregation ratio of offspring at a locus deviates from the Mendelian expectation. In a RIL population, we expect to see half of the alleles come from each parent, 8, and 9 , peaking0-105 cM  with a rS. bicolor × S. propinquum derived populations , base to flag length (BTF), flag to rachis length (FTR), number of nodes (ND) and days to flowering (FL). Means, standard deviation and other summary statistics are shown in Table S1. Broad-sense heritability estimates for all five traits are relatively high (Table S1). It is interesting that the average PH of the progenies is 98.62 cm, greater than the average of either parents, 94.40 for BTx623 and 84.49 for IS3620C. Likewise, BTF is greater than the average of either parent. Both height components show substantial genetic variation, indicating that each parent contributes different alleles for PH to their progenies (Table S1). Moreover, the relatively high genetic variation in PH in this population fosters discovery of QTL, despite that the difference between the two parents is relatively small.The present BTx623 x IS3620C RIL map provides higher power for detecting QTL than a prior map of a subset of these progenies. As examples, we have investigated QTL for five phenotypic traits, plant height (PH and BTF are highly correlated in this population (Table S2), with a correlation coefficient of 0.8983 (P < 0.001). We detect a total of seven and five QTL for PH and BTF, accounting for 40.13% and 41.58% of the total phenotypic variances, respectively (Table S3). Three QTL on chromosomes 3, 6 and 7 overlap for these two traits. The QTL on chromosomes 6 and 7 account for the majority of the phenotypic variance explained for these traits, ∼28% and ∼32% for PH and BTF, respectively. These two large effect QTL might be related to previously defined PH genes, presumably dw2 on chromosome 6 and dw3 (Sb07g023730) on chromosome 7 . For example, the 1-lod interval of QTL on chromosome 7 is narrowed from ∼26 cM previously to only ∼3 cM in this study , and harbors the gene Sb07g023730 (DW3) at ∼58.6 Mb. This example indicates that nearly tripling the numbers of individuals and increasing marker density greatly increased the power of QTL detection.Not only do we detect more QTL than were found in the previous study of a subset of this population (FTR and PH (r = 0.0778), though significant at P < 0.01, is not nearly high as the correlation between the BTF and PH (r = 0.8983), suggesting that the genetic control of these two traits might be different. Indeed, QTL mapping suggests that the genetic control of FTR is quite different from that of PH and BTF, with only one QTL (qFTR7.1) on chromosome 7 overlapping with QTL for PH and BTF (qPH7.1 and qBTF7.1). While the one-LOD QTL interval for qPH10.1 overlaps with qFTR10.1 to some extent, there is no solid evidence to conclude that they are controlled by the same genetic factors, given that the likelihood peaks of the QTL for these two traits are ∼10 cM apart. We detected a total of five QTL for FTR, explaining 28.21% of the total phenotypic variance (Table S3). The additive effect of FTR needs to be carefully interpreted, especially when compared to the additive effect of PH. Since the average value of FTR is negative, a negative number for the additive effect for this trait indicates increased FTR for a particular allele. For example, the additive effect for qFTR7.1 is -1.19, which indicates that FTR of plants carrying the IS3620 alleles are actually longer than those of plants carrying the BTx623 alleles. Both alleles from IS3620C for qPH7.1 and qFTR7.1 have the same effect of increasing length, although the sign of their additive effects is different.An interesting phenotype that we observed is distance from the flag leaf to the rachis. We distinguished whether or not the rachis is immersed in the flag leaf . The correlation coefficient (Table S2) between ND) in this population , an unexpected finding compared to many other sorghum studies , with a peak at 58.4Mb, close to the 58.6 Mb location of the causal gene , and 15 regions contain different traits  (PH on chromosome 6 at ∼42.4cM, in the vicinity of a recently published dw2 candidate gene (dw1 (FL, qFL9.1, that is ∼30cM from qPH9.1. This result again suggests that two separate QTL control these PH and FL effects, a conclusion that is also supported by another study (An unexpected low correlation between We discovered a total of 30 syntenic regions within the sorghum genome sequence . This noPH and FL have been and will continue to be important for sorghum breeding programs. The past century has witnessed breeding for modern varieties with a particular plant type, for example a semi-dwarf type, to realize striking increases in production such as those which led to the “Green Revolution” (PH and FL, together with narrowed QTL intervals, facilitates accurate selection for each trait. The QTL found in this study and their correspondence with those from many other studies also provides a framework for fine mapping or subsequent cloning of major genes for PH and FL in sorghum.Components of olution” . The con