5个冬麦品种产量性状和叶片特征多样性分析

采用单因素完全随机设计,调查5个冬麦品种产量性状和叶片特征多样性。结果表明,5项产量相关性状指标(株高、穗长、主穗粒数、有效分蘖数、有效小穗数)在不同冬麦品种间差异均达显著水平;5个品种的上表皮气孔密度均多于下表皮,其中,上表皮气孔密度为62.67~71.11个/mm2,下表皮气孔密度为30.00~46.25个/mm2;叶脉总数为57.00~65.67条;叶脉密度为36.89~43.00条/mm。     

Freshwater nucleated pearl quality is influenced by host mussel growth traits in Hyriopsis cumingii

Hyriopsis cumingii is one of the most important freshwater pearl mussels in China. Recently, this species can produce freshwater nucleated pearls of high quality. Here, we investigated whether nucleated pearl quality is influenced by the growth traits of the host mussel or other factors like cultivation period. We implanted host mussels with a spherical nucleus consisting of a small piece of mantle tissue from donor mussels. After 24 and 36 months of culture, host mussel growth traits including body weight and shell length, height, width and weight were recorded. These factors were then correlated with the quality traits of the pearls they produced, such as nacre thickness, size, weight, lustre and colour. Results indicated pearls obtained at 36 months after seeding were significantly larger in terms of nacre thickness, size and weight compared to those harvested at 24 months. In particular, nacre thickness (r = 0.33–0.48, P = 0.00), pearl size (r = 0.39–0.43, P = 0.00) and pearl weight (r = 0.35–0.47, P = 0.00) were showed to be significantly correlated with host mussels shell length, body weight and shell weight at 24 or 36 months. Larger and heavier host mussels tended to produce bigger pearls. In contrast, host mussels did not affect pearl colour. Cumulatively, our results suggest that longer culturing times and a larger host mussel may help produce better quality nucleated pearl. This information can help guide selective breeding programs designed to improve pearl quality produced by H. cumingii.     

湖北稻茬小麦主茎、分蘖1、分蘖2和分蘖3的成穗率、产量贡献率及主要农艺性状分析

合理的茎蘖组合是提升小麦绿色高效生产的重要因素。为了解湖北稻茬小麦主要茎蘖对产量及主要农艺性状的影响,以大穗型小麦品种川麦104和多穗型小麦品种扬麦15为材料,于2016-2018年在湖北十堰和武汉两地稻茬麦大田条件下,设置低(1.35×106~1.65×106株·hm^-2)、中(2.85×106~3.15×106株·hm^-2)、高(4.35×106~4.65×106株·hm^-2)三种种植密度,分析了主茎(S)、分蘖1(T1)、分蘖2(T2)和分蘖3(T3)(按出现先后顺序)的成穗率、产量贡献率及相关农艺性状的表现。结果表明:(1)湖北稻茬小麦成穗茎蘖农艺性状表现值偏低,除穗长和茎高受品种的影响最大外,其他被测性状受影响程度表现为蘖位>种植密度>品种;(2)在主茎均能成穗的情况下,分蘖成穗率随蘖位和种植密度的升高而降低,大穗型品种川麦104的降幅大于多穗型品种扬麦15;(3)主茎产量贡献率随种植密度的升高而升高(35.12%~54.50%),分蘖1产量贡献率稳定在23.25%~25.50%,分蘖2和分蘖3的产量贡献率随种植密度升高而降低,分别为14.59%~23.22%和5.42%~16.77%;(4)主茎的穗粒数(35.94~44.13粒)和穗粒重(1.44~1.93 g)显著高于其分蘖,茎高、茎蘖收获指数和穗茎节长只在川麦104中、高种植密度下的分蘖3与其他茎蘖差异显著;穗长、可孕小穗数和不孕小穗数有随蘖位和种植密度升高而变劣的趋势。聚类分析得出:湖北稻茬小麦绿色高效生产模式,以主茎成穗为主体,低种植密度下增加分蘖1和分蘖2,争取分蘖3成穗为辅;中种植密度下争取分蘖1+分蘖2成穗为辅;而高种植密度下争取分蘖1成穗为辅。     

云南籽粒苋种质资源的表型多样性分析

为了系统分析云南籽粒苋种质资源的表型遗传多样性。采用遗传多样性指数、主成分分析、相关分析和聚类分析对104份云南籽粒苋种质资源的30个表型性状进行研究。结果表明,遗传多样性指数最高的质量性状和数量性状分别是主花序形状(1.68)和主花序长度(2.07)。前10个主成分累计贡献率达到73.944%,单株鲜体重与第3、第6、第9主成分极显著正相关,单株粒重与第9主成分极显著正相关。聚类分析将104份种质划分为5类,第Ⅰ类群可为间套种亲本材料,第Ⅱ和Ⅲ类群可为大粒亲本材料,第Ⅳ类群可为优质饲用亲本材料,第Ⅴ类群可为观赏类亲本材料。云南籽粒苋种质资源表型性状具有丰富的遗传多样性,有较大的开发利用潜力。     

不同地区楼葱栽培种的性状与品质分析

为了研究不同地区楼葱的特性,试验对我国不同地区12个楼葱栽培种的数量性状和品质性状进行了测定分析。14个数量性状的相关分析结果显示,主成分分析数量指标后,单株质量、株高、假茎质量、花葶高、叶形指数和假茎指数影响分类;相关性分析说明主要数量指标间具有极显著相关性(P<0.01)。聚类分析后,遗传距离为3.1时可将楼葱种质根据所得主要数量性状分为4个类群。测定不同地区楼葱6个品质指标后,相关性分析结果表明,紧实度与蛋白质含量、干物质率、香辛油含量、总糖含量、游离氨基酸总量存在着极显著正相关或相关性,主成分分析表明主成分反映了89.99%的原有信息量,楼葱的干物质率与紧实度为主要成分;应用灰色关联度分析了品质与数量性状的关系,假茎直径、出叶孔间距、单株质量这3个数量性状对楼葱品质的影响居前3位。研究表明楼葱种质材料具有极其丰富的遗传多样性,宁夏同心2个地区黄水桥HSQ、石羊圈SYJ的楼葱种质距其他种质资源间亲缘关系最远且干物质率含量及紧实度最高。     

杜仲雌花芽2个发育时期转录组分析

杜仲(Eucommia ulmoides)的果实是提取杜仲胶和杜仲籽油的重要原材料,在工业、医疗、食品等领域开发前景广阔。为了揭示雌蕊原基发育相关基因的表达情况,本研究以杜仲果用良种‘华仲6号’(Huazhong No.6)为材料,利用lllumina Hiseq X-10高通量测序平台,分别对花序原基分化期和雌蕊原基分化期的花芽进行转录组测序,通过生物信息学对2个发育时期的雌花芽转录组进行比较分析,筛选出与杜仲雌蕊原基发育相关的差异基因。结果显示,转录组测序共获得68.11 Gb数据,各样品的Clean reads与杜仲基因组进行序列比对,比对效率为91.59%~92.05%,同时2个发育时期共筛选出485个差异表达基因,其中219个差异基因在雌蕊原基分化期表达上调,266个表达下调。差异基因GO富集结果表明,花的发育、光周期现象、激素生物合成以及蛋白结合转录因子活性等相关的生物途径被富集。KEGG富集结果表明淀粉和蔗糖代谢、碳代谢、昼夜节律和植物激素信号转导等代谢通路被富集。结果表明光周期途径是诱导杜仲成花的重要途径,且雌蕊原基发育受碳水化合物、植物激素和其他代谢物质调控。本研究为杜仲花器官发育调控基因的挖掘提供了基础数据,也为果用杜仲的分子育种提供了参考。     

Genetic variation of seedling traits responded to brassinosteroid and gibberellin inhibitors in maize (Zea mays) doubled haploid lines

The purpose of this study was to examine the genotypic variation in maize doubled haploid (DH) lines response to brassinosteroid and gibberellin inhibitors. Plant responses to hormone inhibitors were determined in growth chamber experiments using germination paper for three different seedling treatments: application of propiconazole (Pcz), uniconazole (Ucz) or water (control). Mesocotyl length (ML) was more sensitive to hormone inhibitors, especially to the Ucz treatment, than other seedling traits. ML was significantly correlated with other traits in the Ucz treatment. All the seedling traits showed moderate-to-high broad sense heritability values, ranging from 0.39 to 0.82. The Euclidian genetic distances of inbred line pairs ranged from 1.27 to 19.94, indicating there was a high level of variability across the maize DH lines used in this study. DH lines with extreme MLs were identified, which can provide valuable breeding resources for improving abiotic stress tolerance, and for further genetic studies.     

Quantitative trait loci mapping for yield-related traits under low and high planting densities in maize (Zea mays)

Average maize yield per hectare has increased significantly because of the improvement in high-density tolerance, but little attention has been paid to the genetic mechanism of grain yield response to high planting density. Here, we used a population of 301 recombinant inbred lines (RILs) derived from the cross YE478 × 08–641 to detect quantitative trait loci (QTLs) for 16 yield-related traits under two planting densities (57,000 and 114,000 plants per ha) across four environments. These yield-related traits responded differently to high-density stress. A total of 110 QTLs were observed for these traits: 33 QTLs only under low planting density, 50 QTLs under high planting density and 27 QTLs across both densities. Only two major QTLs, qCD6 and qWKEL2-2, were identified across low- and high-density treatments. Seven environmentally stable QTLs were also observed containing qED6, qWKEL3, qRN3-3, qRN7-2, qRN9-2 and qRN10 across both densities, as well as qRN9-1 under low density. In addition, 16 and eight pairs of loci with epistasis interaction (EPI) were detected under low and high planting densities, respectively. Additionally, nine and 17 loci showed QTL × environment interaction (QEI) under low- and high-density conditions, respectively. These interactions are of lesser importance than the main QTL effects. We also observed 26 pleiotropic QTL clusters, and the hotspot region 3.08 concentrated nine QTLs, suggesting its great importance for maize yield. These findings suggested that multiple minor QTLs, loci with EPI and QEI, pleiotropy and the complex network of “crosstalk” among them for yield-related traits were greatly influenced by plant density, which increases our understanding of the genetic mechanism of yield-related traits for high-density tolerance.     

Determination of growth,colour and other traits in F1 hybrid of Amphiprion percula (male) × A. ocellaris (female)

This study reported the traits values such as colour, feed conversion ratio (FCR), specific growth rate (SGR) and fluorescence capacity of F₁ hybrids of Amphiprion percula (male) and A. ocellaris (female). The hybrids exhibited significant variation in FCR (3.63 ± 0.56) and SGR (3.63% ± 0.44) compared with the pure breeds, A. percula (3.12 ± 0.42; 2.80% ± 0.42) and A. ocellaris (3.17 ± 0.43; 3.02% ± 0.19). An exponential relationship was found between FCR and SGR in both the breeds. Image analysis displayed a better colour performance of hybrid than the pure breeds. Individual body parts of the hybrid and pure breeds showed significant colour variation between each other. However, colour contrast of whole body of hybrid was found closer to A. ocellaris in hue cone and towards A. percula in saturation and brightness values. Hence, hybrid displays combination colour reflexion of both the parents. The total pigment content of hybrid (65.71 μg g^?1 ± 2.81) was found higher than A. ocellaris (62.01 μg g^?1 ± 2.29) and A. percula (56.71 μg g^?1 ± 2.56). Further, the spectroflurometric analysis revealed that the both hybrid and pure breeds having poor fluorescence on skin pigmentation. A direct positive heterosis was observed on the SGR, FCR, total pigment and spawning frequency, while negative effect was noted on total length of newly hatched larvae (TL), fertilization rate (FrR), hatching rate (HR), deformation rate (DFR) and survival rate (SR). Hence, multiple cross‐breeding programmes will help in developing high‐quality traits in successive generations.     

苏姜猪A-FABP基因遗传多态性及其与肉质性状的关联分析

研究采用PCR-RFLP技术分析苏姜猪、姜曲海猪、长白猪群体A-FABP基因遗传多态性,并用统计学方法分析基因座多态与肉质性状的相关性。结果表明:3个猪种A-FABP基因内含子1均具有Bsm I酶切多态性,分别检测到3种基因型(AA、AB和BB),χ~2适合性检验显示,3个猪种A-FABP基因型分布处于Hardy-Weinberg平衡(P0.05)。多态信息含量(PIC)分析显示,3个品种猪均为中度多态;基因型与肉质性状关联分析显示,不同基因型肌内脂肪含量、大理石纹差异显著,大理石纹AA、AB型显著高于BB型(P0.05),肌内脂肪含量AA显著高于AB、BB型(P0.05)。结论显示,苏姜猪、姜曲海猪、长白猪A-FABP基因intron 1多态性对肉质性状影响显著。