陆地棉SRO基因家族的鉴定及表达分析

SRO是植物特有的类RCD-ONE蛋白家族,在植物抵御各种生物和非生物胁迫过程中具有重要的作用。本研究利用生物信息学方法从陆地棉遗传标准系TM-1(Gossypium hirsutum L.acc.TM-1)基因组中鉴定到12个SRO基因家族成员。多重序列比对及进化树分析表明,12个陆地棉SRO均含有PARP和RST结构域,聚为3类,即A、B和C亚家族。转录组数据分析表明,TM-1全基因组中的Gh_D12G1442在茎中优势表达,Gh_D05G2064在萼片和雄蕊中优势表达;Gh_A05G3788在雄蕊中优势表达,Gh_A12G1318在雄蕊和纤维中优势表达;Gh_A12G2480、Gh_D12G2608、Gh_A05G2257和Gh_D05G2516在纤维中优势表达;Gh_A08G1390、Gh_D08G1685、Gh_A12G2663和Gh_D12G2054具有较为广泛的组织表达。逆境胁迫处理试验表明,Gh_A08G1390明显受冷处理和盐处理的诱导,Gh_D12G2054、Gh_D08G1685、Gh_A12G2663基因在不同的胁迫处理下受到不同程度的诱导。     

Mapping QTL of Fiber Yield and Quality Traits in F2 Populations of Chromosome Segment Substitution Lines from Gossypium hirsutum × Gossypium barbadense

In this study, F₂ populations from two chromosome segment substitution lines MBI7455 and MBI7358, were quantified using SSR to evaluate the parents' genotype and detect QTL related to fiber quality plus yield traits of cotton. Results show that the recurrent parent (CCRI45) hosted 96.70% and 95.60% of chromosome segment substitution in MBI7455 with 12 chromosome segments and in MBI7358 with 16 chromosome substitution segments of Gossypium barbadense, respectively. In the F₂ population, the average rate of chromosome substitution of the recurrent parent (CCRI45) was 96.44%, and the average segments of chromosome substitution of Gossypium barbadense was 13.42, with an average segments of homozygous donor chromosome value of 3.90. Analysis showed 19 fiber quality-related QTL with a phenotypic variance of between 2.52%-13.11% and seven yield traits-related QTL with a range of 2.93%-11.40% phenotypic variance, resulting in a total of 26 QTL. The CSSLs could be used to detect QTL for fiber yield and quality traits, which offer an important foundation for the cotton molecular-assisted breeding.     

棉花陆海染色体片段代换系BC_7F_2群体纤维产量和品质性状表现及相关分析

为了揭示棉花染色体片段代换系BC_7F_2纤维产量性状和品质性状之间的相关关系,筛选纤维品质优异的新材料。以1套陆海染色体片断代换系为材料,对BC7F2高代回交群体的产量性状与纤维品质性状的表性数据进行评价及偏相关分析。结果表明:群体各性状的平均值接近于轮回亲本‘中棉所36’,群体内存在丰富的遗传变异。纤维上半部平均长度超轮回亲本比例为30.25%,断裂比强度超轮回亲本比例为71.25%,衣分超轮回亲本比例为29.38%。总体上单铃重与马克隆值、整齐度指数呈极显著正相关,衣分与上半部平均长度、断裂比强度呈显著负相关,与单铃重呈极显著负相关。从中筛选出部分纤维品质突出的单株,纤维上半部平均长度高于30.00 mm,断裂比强度高于31.00 cN/tex。     

棉花单核苷酸多态性标记研究进展

单核苷酸多态性标记已在农作物研究中得到广泛应用并取得重大进展。为了便利棉花SNP(Single nucleotide polymorphism)标记的研究和应用,介绍了利用基因芯片、简化基因组测序、重测序等在棉花中开发SNP标记的方法 ,综述了SNP标记在棉花遗传图谱构建、数量位点的定位和分子标记辅助育种、基因组测序以及系统进化等研究中的应用。并对异源四倍体棉花中SNP标记开发时,同源序列位点和部分同源序列位点上的SNP标记辨别问题进行了系统探讨,对其快捷的开发、检测方式和在数量基因定位中的应用前景进行了展望。     

Nitrogen use efficiency of cotton (Gossypium hirsutum L.) as influenced by wheat–cotton cropping systems

Wheat–cotton rotations largely increase crop yield and improve resources use efficiency, such as the radiation use efficiency. However, little information is available on the nitrogen (N) utilization and requirement of cotton under wheat–cotton rotations. This study was to determine the N uptake and use efficiency by evaluating the cotton (Gossypium hirsutum L.) N use and the soil N balances, which will help to improve N resource management in wheat–cotton rotations. Field experiments were conducted during 2011/2012 and 2012/2013 growing seasons in the Yangtze River region in China. Two cotton cultivars (Siza 3, mid-late maturity with 130 days growth duration; CCRI 50, early maturity with 110 days growth duration) were planted under four cropping systems including monoculture cotton (MC), wheat/intercropped cotton (W/IC), wheat/transplanted cotton (W/TC) and wheat/direct-seeded cotton (W/DC). The N uptake and use efficiency of cotton were quantified under different cropping systems. The results showed that wheat–cotton rotations decreased the cotton N uptake through reducing the N accumulation rate and shortening the duration of fast N accumulation phase as compared to the monoculture cotton. Compared with MC, the N uptake of IC, TC and DC were decreased by 12.0%, 20.5% and 23.4% for Siza 3, respectively, and 7.3%, 10.7% and 17.6% for CCRI 50, respectively. Wheat–cotton rotations had a lower N harvest index as a consequence of the weaker sink capacity in the cotton plant caused by the delayed fruiting and boll formation. Wheat–cotton rotations used N inefficiently relative to the monoculture cotton, showing consistently lower level of the N agronomic use efficiency (NAE), N apparent recovery efficiency (NRE), N physiological efficiency (NPE) and N partial factor productivity (NPFP), particularly for DC. Relative to the mid–late maturity cultivar of Siza 3, the early maturity cultivar of CCRI 50 had higher N use efficiency in wheat–cotton rotations. An analysis of the crop N balance suggested that the high N excess in preceding wheat (Triticum aestivum L.) in wheat–cotton rotations led to significantly higher N surpluses than the monoculture cotton. The N management for the cotton in wheat–cotton rotations should be improved by means of reducing the base fertilizer input and increasing the bloom application.     

中国棉花主栽品种棉子营养品质及播种品质研究

为了明确中国棉花主栽品种营养品质及播种品质的状况,揭示中国当前的棉花育种现状,为合理利用棉副产品及棉花特定目标育种提供参考。对当前中国三大主产棉区的142份棉花主栽品种棉子的营养品质性状(蛋白质、油分含量)、播种品质性状(发芽率)及3个物理性状(子指、仁指和仁子比)进行检测分析。结果表明:当前主栽棉花品种的营养品质非常接近,油分含量集中于27.1%~33.0%,棉子的蛋白质含量集中区域为41.0%~45.0%,高油和高蛋白含量的棉花品种较少;蛋白质和油分总量变异较小,且两者呈高度负相关关系。棉种播种质量的4个必检项水分、净度、发芽率及纯度的平均值分别9.6%、100.0%、87.8%和97.1%,在连续3年的监督抽查中水分和净度的合格率均为100%,不合格项主要出现在纯度及发芽率上。研究结果较真实地反映了棉籽营养品质性状与播种品质的现状,适时开展棉花多目标育种十分必要,但对油分与蛋白质含量进行同步改良的难度较大。     

Effect of water deficiency on relationships between metabolism,physiology,biomass,and yield of upland cotton(Gossypium hirsutum L.)

Drought is a common abiotic stress that considerably limits crop production. The objective of this study is to explore the influence of water deficiency on the yield, physiologic and metabolomic attributes in upland cotton cultivars(Gossypium hirsutum L). Cotton cultivars, 'Ishonch' and 'Tashkent-6' were selected to study the relationships among their physiologic, metabolomic and yield attributes during water deficiency. Deficit irrigation was designed by modifying the traditional watering protocol to reduce water use. Results indicate that cotton cultivars respond differently to water deficit stress. Water deficit significantly influenced plant height, the number of internodes, and sympodial branches in both cultivars. However, yield components such as the number of bolls, boll seed, lint mass, and individual plant yield were significantly reduced only in 'Tashkent-6'. The leaf area decreased and the specific leaf weight increased in 'Ishonch' under deficit irrigation conditions. However, 'Tashkent-6' demonstrated significant water loss compared to 'Ishonch', and both cultivars showed reduced transpiration rates. Untargeted metabolite profiles of leaves showed clear separation in 'Ishonch', but not in 'Tashkent-6' under deficit irrigation compared to full irrigation. The individual metabolites such as proline and galactinol showed strong association with yield under water deficit stress. Moreover, this study indicates that leaf area and transpiration intensity influence yield during water deficiency. In summary, the correlation among morpho-physiologic, metabolic, and yield components significantly varied between the two cultivars under water deficiency. The flowering stage was sensitive to water stress for both cultivars. The direct relationship between physiology, metabolism, and yield may be a useful selection criterion for determining candidate parents for cotton drought tolerance breeding.     

Cotton Research Center,Shandong Academy of Agricultural Sciences,Jinan 250100, China

During the long process of evolution, plants have adapted to their environments through the biosynthesis of secondary metabolites (SM) using the acetate-malonate pathway, mevalonic acids pathway, or shikimic acid pathway, leading to resistance to different pests. As a major cash crop, cotton can produce many secondary metabolites with insecticidal activity, and show self-defense mechanisms under biotic stress conditions. These characteristics of cotton ensure reduced pest incidence and maintenance of ecological balance. This paper discusses the types of SMs, their synthesis, and insect resistance of cotton secondary metabolites in relation to their defense function. We propose possible pest-control strategies using secondary metabolites in cotton.