大豆不同生育时期叶绿素含量QTL的定位及其与产量的关联分析

利用来自波高×南农94-156的151个RI家系检测与4个不同生育时期叶绿素含量（累积量、净增量）有关的QTL,并分析其与籽粒产量、表观生物学产量和表观收获指数的关系。结果表明,与叶绿素累积量有关的QTL位于D1a+Q、F、G、H、L和M连锁群上,每个QTL可解释表型变异的6.9%~23.4%。V6和R2期没有检测到2个年份均表达的QTL,而在R4期检测到4个在2个年份均表达的QTL（qccF.1、qccG.2、qccH.1和qccM.1）,R6期仅检测到1个QTL（qccH.1）在2个年份均表达,该QTL在R4也表达。与叶绿素含量净增量有关的QTL位于B2和L连锁群上,在V6-R2时期没有检测到与叶绿素净增量有关的QTL,在B2和L连锁群上的两个QTL（qccB2-1.1和qccL.1）在R2-R4和R4-R6时期均表达,qccB2-1.1可解释表型变异的6.4%~9.8%,而qccL.1所解释表型变异达29.5%~31.3%。但这两个QTL在R2-R4和R4-R6时期表达的性质不同,且与2年均表达的籽粒产量QTL共位。这印证了生育后期叶绿素含量与籽粒产量间存在的极显著正相关。     

Interaction Amongst Soybean [Glycine max (L.) Merrill] Genotype, Soil Type and Inoculant Strain with Regard to N2 Fixation

The nitrogen (N₂)‐fixing bacterial inoculant strain for soybean [Glycine max (L.) Merrill] is not indigenous to South African soils. The interaction between soybean genotype, soil type and inoculant strain, however, has a definite influence on soybean production and compatibility should be optimized. This paper reports a growth chamber study using three different soybean genotypes (Barc‐9, Avuturda and Talana), three Bradyrhizobium japonicum inoculant strains (WB108, WB112 and WB1) and three soil types (Avalon, Arcadia and sand) to evaluate the effectiveness of N₂ fixation by different genotype × soil type × inoculant strain combinations, using different measuring parameters. These parameters included nodule fresh mass (NFM), amount of N₂ fixed (P_fix), as determined by the ureide method, seed protein content (SPC), average seed mass per plant (SMP) and average foliar N content (FNC). The comparison amongst the three‐way interactions, genotype × soil type × inoculant strain, did not differ significantly for the parameters used. Significant two‐way interactions were soil × inoculant for FNC, P_fix and SMP; soil × genotype for FNC and SMP, and inoculant × genotype for FNC (P < 0.05). The soil × inoculant strain interaction was significant for P_fix (P < 0.05). NFM, P_fix, FNC, SMP and SPC correlated positively with soil pH and negatively with soil clay content and soil NO₃^– and NH₄⁺ content (P < 0.05). SPC was significantly different (P < 0.05) for soil type, genotype and inoculant strain. P_fix and NFM did not reflect the protein content of the seeds, indicating that nodule evaluation should be used with caution as a N₂ fixation parameter. Low soil pH and high mineral N content inhibited N₂ fixation. NFM correlated negatively with the clay content of the soil. This finding confirms that soybean production in South Africa can be improved by appropriate selection of genotypes and inoculant strains for their compatibility in different soils.     

Genetic analysis for the leaf pubescence density and water status traits in soybean [Glycine max (L.) Merr.]

Leaf pubescence density (PD) is an important component for the adaptation of soybean [ Glycine max (L.) Merr.] to drought-prone environment. Quantitative trait loci (QTL) controlling PD on the upper surface of leaf blade (PDU), PD on the lower surface of leaf blade (PDL), leaf wilting coefficient (WC) and rate of excised leaf drying (ELD) were identified using recombinant inbred lines (RILs) population from the cross between soybean cultivars 'kefeng1' and 'nannong1138-2' at the field soil drought stress stage from the mid-end of stem elongation to onset of flowering. A total of 20 QTLs were detected on molecular linkage groups (MLGs) A2, D1b, E, H, G and I with individual QTL explained 4.49–23.56% of phenotypic variation by composite interval mapping. The QTLs for PD on MLG H were mapped to near Ps locus while the QTLs on MLG D1b were located near Rsc-7 . Three genome regions for PD and water status traits on MLGs A2, D1b and H were associated. This study revealed that leaf surface PD may play an important role in the soybean drought tolerance.     

大豆根区逆境耐性的种质鉴定及其与根系性状的关系

依根系类型从黄淮海和长江中下游地区301份代表性材料中选取62份，以株高、叶龄、地上部干物重、地下部干物重为指标，采用平均隶属函数值方法鉴定了苗期耐旱性、苗期耐铝毒性，加上主茎节数、分枝数、单株荚数、单株粒数、百粒重等性状鉴定了后期耐旱性，并通过钒钼黄比色法测定植株P含量鉴定了苗期耐低磷性。筛选出1级苗期     

黄淮海地区大豆耐旱根系性状的遗传分析

从83份黄淮海地区代表性材料中按根系类型选取28份,在苗期以株高、叶龄、根干质量和茎叶干质量隶属函数的平均值为指标进行2年耐旱性重复鉴定,从中筛选出晋豆14强耐旱型材料。比根干质量、比总根长、比根体积与耐旱隶属函数值均呈极显著正相关,可作为耐旱性的根系性状指标。利用科丰1号×南农1138-2衍生的RIL群体为材料,对耐旱相关根系性状采用主基因 多基因混合遗传模型分离分析法进行遗传分析。结果表明,该两亲本间比根干质量、比总根长、比根体积的遗传均为两对主基因加多基因模型,后两者主基因间有连锁(重组率4.30%,1.93%);主基因遗传率为62.26%~91.81%,多基因遗传率为2.99%~24.75%;耐旱相关根系性状各主要由1对主基因控制,另1对效应较小,三性状的改良均着重在主基因加性效应。     

Major QTLs associated with green stem disorder insensitivity of soybean (Glycine max (L.) Merr.)

Green stem disorder (GSD) is one of the most serious syndromes affecting soybean (Glycine max) cultivation in Japan. In GSD, stems remain green even when pods mature. When soybean plants develop GSD, seed surfaces are soiled by tissue fluid and seed quality is deteriorated during machine harvesting. We performed quantitative trait locus (QTL) analyses for GSD insensitivity using recombinant inbred lines (RILs; n = 154) derived from a cross between an insensitive line (‘Touhoku 129’) and a sensitive leading cultivar (‘Tachinagaha’) during a 6-year evaluation. Three effective QTLs were detected. The influences of these QTLs were in the following order: qGSD1 (LG_H) > qGSD2 (LG_F) > qGSD3 (LG_L). At these three QTLs, ‘Touhoku 129’ genotypes exhibited more GSD insensitivity than ‘Tachinagaha’ genotypes. The lower incidence of GSD for ‘Touhoku129’ was attributable primarily to these three QTLs because RILs harboring a ‘Touhoku 129’ genotype at the three QTLs exhibited a GSD incidence similar to that of ‘Touhoku 129.’ Although a limitation of this study is that only one mapping population was evaluated, this QTL information and the flanking markers of these QTLs would be effective tools for resolving GSD in soybean breeding programs.     

大豆苗期耐淹性的遗传与QTL分析

涝害是世界上许多国家的重大自然灾害。耐涝性可分为耐湿(渍)性和耐淹性。以科丰1号(高度耐淹)×南农1138-2(不耐淹)衍生的RIL群体(NJRIKY)为材料, 以盆栽全淹条件下的存活率为耐淹性指标, 采用主基因+多基因混合遗传模型分离分析法进行遗传分析, 并利用WinQTL Cartographer Version 2.5程序的复合区间作图法(CIM)及多区间作图法(MIM)进行QTL定位。结果表明, 两次试验的耐淹性均存在超亲变异, 试验间、家系间以及试验与家系互作间的差异均极显著; NJRIKY大豆群体的耐淹性为3对等加性主基因遗传模型, 主基因遗传率为42.40%; 在QTL分析中, 用CIM和MIM共同检测到3个耐淹QTL, 分别位于A1、D1a和G连锁群上的Satt648~K418_2V、Satt531~A941V、Satt038~Satt275 (B53B~Satt038)区间, 表型贡献率为4.4%~7.6%。分离分析与QTL定位的结果相对一致, 可相互印证。     

吉林省大豆品种遗传改良过程中主要农艺性状的变化

以吉林省1923—2005年间育成的30个大豆品种为材料, 两年的研究结果表明, 大豆种子产量随育成年代呈线性增加, 根据回归方程计算, 产量从1923年的1 197.80 kg hm^-2到2005年的2 305.54 kg hm^-2, 82年来增加了 1 107.73 kg hm^-2, 平均每年增加14.60 kg hm^-2。随着产量的提高, 株高降低, 主茎直径增加, 节数增多, 节间缩短, 分枝减少。相关和通径分析表明, 产量与单株荚数、单株粒数、单株叶面积、叶面积指数和单株复叶数目呈显著正相关(P<0.05), 单株荚数和单株粒数对于产量的提高贡献最大; 产量与株高、单株分枝数和倒伏指数呈显著负相关(P<0.05), 表明大豆产量的遗传改良过程中, 植株抗倒伏能力提高, 库容量增加, 源器官叶片的同化能力增强。     

利用大豆分子连锁图定位大豆孢囊线虫4号生理小种抗性QTL

大豆孢囊线虫 (SCN ,HeteroderaglycinesIchinohe)是一种土传的定居性内寄生线虫 ,是引起大豆黄萎病的病原 ,是大豆生产上危害最大的病害之一。SCN的生理小种多达十几种 ,在我国大豆孢囊线虫病原主要为 4号生理小种 ,它是现有生理小种中致病力最强的小种。经典遗传学研究已经确定大豆孢囊线虫抗性基因由 1- 4对核基因控制 ,估计有 10个以上的抗性座位。近年来分子标记技术及QTL定位方法的发展为深入研究该病害的抗性遗传规律提供了有效的手段 ,这对加速我国抗大豆抗孢囊线虫新品种培育具有重要意义。本研究以晋豆 2 3×ZDD2 315组合F2 群体 (2 5 3个单株 )为试验材料 ,其中灰布支黑豆 (ZDD2 315 )是我国山西省农家品种 ,对大豆孢囊线虫 4号生理小种表现为高抗。利用塑料钵柱法进行SCN抗性鉴定 ,构建大豆孢囊线虫抗性主座位所在区域的分子图谱 ,并进行SCN的QTL定位及遗传效应分析。根据已发表的大豆A和G连锁群的分子遗传图谱 ,应用BSA法 ,获得了 8个与SCN4号生理小种抗性基因相关的SSR标记 ,它们是Satt0 38(176bp/ 182bp) ,Satt30 9(130bp/ 135bp) ,Satt6 10 (2 4 0bp/ 2 2 2bp) ,Sat_14 1(189bp/ 184bp) ,Satt187(30 0bp/ 2 5 0bp) ,Satt315 (2 5 3bp/ 2 4 8bp) ,Satt6 32 (2 86bp/ 2 90bp)和Sat_16 2(2     

Uniformity, Performance and Seed Quality of Soybean (Glycine max (L.) Merrill) Seed Crops Grown from Sub-samples of One Seed Lot Obtained after Selection for Physical Seed Attributes

In a glasshouse experiment it was examined whether narrow grading and selection from a commercial soybean seed lot cultivar 'IAS-5', could improve the uniformity of the seed crop grown from it and thereby enhance yield, quality and uniformity of seeds produced. The classes created were: Control (original seed lot); Size-graded seeds (projected area measured by image analysis 37–46 mm²); Non-cracked seeds; Yellow seeds; Size-graded sound seeds (size-graded, non-cracked, yellow, non-wrinkled, non-etched). Compared to the control, percentage of emergence, survival and number of yielding plants were enhanced in crops from non-cracked, yellow or size-graded sound seeds. Differences in plant numbers did not result in differences in crop yield. The different seed lots also did not differ in crop uniformity: time interval between stages of plant development, plant height 20 days after sowing, yield components, physical or physiological quality attributes of seeds produced, and respective coefficients of variation were similar. Fewer plants survived in crops showing a larger variation in plant height 20 days after sowing, thus reducing differences in initial plant-to-plant variation. Creating more uniform crops by additional grading or selection of commercial seed lots may therefore not be promising.     

Effect of Deep Placement of Slow-release Fertilizer (Lime Nitrogen) Applied at Different Rates on Growth, N2 Fixation and Yield of Soya Bean (Glycine max [L.] Merr.)

A new fertilization method with deep placement of slow‐release N fertilizers, such as coated urea and lime nitrogen (LN) (calcium cyanamide) at 20 cm depth was found to promote soy bean seed yield. In the present study, the effect of deep placement of LN was investigated on different parameters such as growth, N accumulation, N₂ fixation activity and yield of soy bean by applying LN at different rates in the rotated paddy field of Niigata, Japan. In addition to the basal fertilizer, ammonium sulphate (16 kg N ha^?1), deep placement of LN was conducted by applying various amounts such as 50 kg N ha^?1 (A50), 100 kg N ha^?1 (A100) and 200 kg N ha^?1 (A200) at 20 cm depth in separate plots. A ¹⁵N‐labelled LN fertilizer was also employed for each of the above treatments to calculate N utilization from LN in separate plots. Soya bean plant growth and N₂ fixation activity were periodically analysed. Both plant growth and N accumulation were found to increase with LN treatment compared with control plants. An increase in N₂ fixation activity was found in the A100 plots. The total seed yield was the highest in the deep placement of LN with A100 (73 g per plant) compared with other treatments. The visual quality of harvested seeds also showed that A100 enhanced the quality of seeds compared with other treatments. Thus, it is suggested that N fertilization management with particular reference to optimum amount of fertilizers is important for maximum growth, N₂ fixation and enhancement of seed yield of soy bean.