【Objective】Aiming at the low temperature in early spring and poor moisture retentionability of main soybean producing areas in the northern part of Northeast China, the effects of different intertillage times and depths on soil temperature and humidity, photosynthetic characteristics and yield of soybean field under maize-soybean rotation mode were explored to provide a strong support for the stable improvement of soybean yield.【Method】The experiment was carried out in Heshan farm, Heilongjiang province from 2019 to 2020. The plot experiment method was adopted, and Heihe 43, the main local cultivator, was used as the test material. Four different intertillage treatments were set up: conventional earthing-up (T1), advanced earthing-up (T2), conventional subsoiling (T3), and advanced subsoiling (T4). The effects of intertillage time and depth on soil temperature and humidity, plant leaf area index and height, gas exchange parameters, accumulation and distribution of photosynthetic products and yield of soybean were studied.【Result】(1) On the basis of the same intertillage depth, compared with T1, soil temperature and humidity in flowering stage (R2 stage) under T2 increased by 5.88%-6.54% and 3.57%-4.03% (P<0.05), respectively, and leaf area index, plant height and SPAD values in seed-filling stage (R6 stage) were increased by 9.48%-16.86%, 5.40%-10.57% and 2.39%-6.81% (P<0.05), respectivley. Compared with T3, T4 significantly increased leaf area index, plant height, net photosynthetic rate (Pn), grain dry matter accumulation and soybean yield at R6 stage. (2) Compared with T1, T3 increased soil temperature and humidity in R2 stage by 4.14%-6.42%, 10.08%-13.19% and plant height in R6 stage by 7.43%-8.29% (P<0.05), respectively. After pod-setting stage (R5 stage), dry matter accumulation and assimilation contribution rate increased by 49.75% and 32.95% (P<0.05), respectively. Compared with T2, T4 significantly increased soil temperature, leaf area index at R6 stage, net photosynthetic rate (Pn), dry matter accumulation after R5 stage, assimilation contribution rate and yield, among which the yield increased by 5.03%-6.02% (P<0.05). (3) Compared with T1, T4 increased soil temperature and humidity by 11.68%-17.15% and 4.70%-8.66% in R2 stage (P<0.05), respectively. Leaf area index, plant height and SPAD in R6 stage were increased by 12.64%-27.42%, 11.67%-13.50% and 5.43%-6.87% (P<0.05), respectively. T2, T3 and T4 increased gas exchange parameters and yield in R6 stage, and net photosynthetic rate (Pn) under T4 treatment increased by 14.25%-29.68%, and yield increased by 10.69%-18.71% (P<0.05).【Conclusion】T4 could improve soil temperature and humidity, increase gas exchange parameters, promote plant net photosynthate accumulation, and delay leaf senescence, finally increase soybean yield, which was suitable for the promotion and application of dry farm areas in the north of Northeast China.

以大豆干旱敏感型品种绥农26为材料,采用室内培养法,研究不同浓度褪黑素(0、100、300、500、800μmol·L-1)浸种对6％PEG-6000模拟干旱胁迫条件下大豆种子萌发的影响.结果表明:干旱胁迫处理抑制了大豆种子萌发,与对照(蒸馏水处理种子)相比,处理D(6％PEG处理种子)的发芽势、发芽率、根体积和鲜重显著降低,降幅分别为38.14％、23.72％、21.4％、25.6％;根系电导率、MDA和H2O2含量大幅上升,增幅分别为51.18％、83.33％和60.60％.而褪黑素浸种处理(100、300、500、800μmol·L-1)显著缓解了干旱胁迫对种子萌发的抑制,促进了根系生长,其中以根直径和干重提升最为显著,分别增加了16.38％、29.73％、34.97％、31.72％和10.70％、14.28％、10.70％、25.00％;抗氧化酶(SOD、POD、CAT、APX)活性提高,其中处理M500+D(500μmol·L-1褪黑素+6％PEG)效果最为显著,增幅分别为37.61％、40.10％、12.96％和28.31％.在6％PEG-6000模拟的干旱胁迫下,500μmol·L-1褪黑素浸种处理对大豆种子萌发过程中干旱胁迫的缓解效果最佳.

为揭示不同中耕措施对土壤水分与大豆产量的影响,综合考虑中耕的深松深度,深松与培土时间、深松和培土次数,设置提前培土、提前深松、常规深松和常规培土4种不同中耕措施处理,研究不同中耕措施对土壤状况、水分含量及大豆生长发育及产量的影响.结果 表明:深松较培土降低了土壤容重,降幅为3.1％ ～6.4％.深松提高了水分入渗率,进而提高了土壤的含水量与贮水量,提前深松、常规深松处理均显著高于常规培土处理的含水量,在苗期0～～5 cm土层中较常规培土处理分别显著提高10.8％和19.1％,结荚期与成熟期的土壤含水量依旧显著高于常规培土处理.提前深松和常规深松处理的土壤贮水量均显著高于常规培土处理,在结荚期差异最大,分别较常规培土处理显著提高21.5％和16.3％.提前中耕或者深松均提高了叶面积指数,结荚期的提前培土、提前深松和常规深松处理较常规培土处理分别显著提高了28.5％、32.2％和22.7％.大豆前中期的株高表现为提前深松较常规培土处理显著提高,而后期差异不大.提前深松通过降低土壤容重和提高土壤含水量与贮水量,促使大豆叶面积指数和株高的增加,使得各器官的干物质积累更高,进而提高了大豆产量,最终提前深松的产量较常规培土处理提高8.7％.研究结果表明提前深松有助于该地区大豆产量的提高.

为明确2种生长调节剂烯效唑与矮壮素复配微量元素对大豆生长的影响,促进复合型生长调节剂在生产实际中的应用,采用小区对比方式,设置4个烯效唑和矮壮素与微量元素复配拌种处理,烯效唑+微量元素(S)、矮壮素+微量元素(C)、烯效唑与矮壮素混合+微量元素(S+C)和不拌种(CK)处理,研究2种激素与微量元素复配拌种对大豆光合、荧光特性、干物质积累及产量的影响.结果 表明:光合荧光特性方面,与CK相比,S、C、S+C处理提高了苗期、结荚期、鼓粒期大豆叶片净光合速率(Pn)、蒸腾速率(Tr)、胞间CO2浓度(Ci)和气孔导度(Gs),各项指标的平均提高幅度分别为17.3％ ～42.8％、25.2％～ 52.8％、4.6％～5.4％、19.9％ ～ 30.8％;S、C、S+C处理能够改善苗期、结荚期和鼓粒期叶片φPSⅡ、ETR、Fv/m和Fv/o值,平均提高幅度分别为26.7％ ～71.1％、25.8％～ 60.5％、7.4％ ～15.7％、51.1％ ～89.1％;大豆形态方面,与CK相比,苗期时S、C和S+C处理的株高分别降低3.5％、3.1％和3.4％,而单株叶面积平均增长2.4％～23.4％;S+C、S和C处理更能促进地下部器官的生长发育;产量方面,S+C和S处理能够显著增加大豆单株粒数与单株荚数,增长幅度分别为12.3％ ～ 22.1％和19.3％ ～ 20.7％,与CK相比,S、C和S+C增产幅度为20.2％、5.9％和22.7％.综上所述,烯效唑与矮壮素复配微量元素能够提高光合作用气体交换参数、改善荧光指标、促进苗期地下部生长、提高单株荚数和粒数,最终提高大豆产量.S+C处理效果显著,适合黑龙江省垦区实际生产应用,复合植物生长调节剂与微量元素配施对大豆生长水平具有正向促进作用且效果好于单独使用植物生长调节剂.

为探明增密条件下减量施氮和接种根瘤菌对红小豆氮素吸收和产量的影响.于2015～2018年在黑龙江省和平牧场开展玉米-红小豆轮作长期定位试验,试验采用裂区设计,设置M1(21万株·hm-2)、M2(28万株·hm-2)2种种植密度,F1(当地常规模式:基肥一次性施用N 40 kg·hm-2,不接种根瘤菌)、F2(基肥施N 10 kg·hm-2+初花期施N 10 kg·hm-2+不接种根瘤菌)和F3(基肥施N 10 kg·hm-2+初花期施N 10 kg·hm-2+根瘤菌拌种)3种种植方式,比较了2018年减量施氮下通过根瘤菌拌种对增密条件下红小豆氮素吸收、氮素转运和产量的差异及相互间的关系.试验结果表明:相同密度条件下,与F1处理相比,F3处理鼓粒满期营养器官氮素含量增加幅度4.44％～11.2％(P<0.05),鼓粒满期和收获期植株氮素积累量增加幅度为5.61％～9.28％(P<0.05),鼓粒期-鼓粒满期和鼓粒满期-收获期阶段氮素积累量增加幅度4.31％～24.5％(P<0.05),转运贡献率降低7.00％～11.1％(P<0.05),同化贡献率增加幅度12.5％～17.1％(P<0.05),产量增加幅度2.89％～4.60％.相同种植模式下,密度从21万株·hm-2增加到28万株·hm-2时,花荚期后氮素积累量、氮素同化贡献率、鼓粒期-鼓粒满期氮素阶段积累量和产量均随着密度的增加而降低.综上,种植密度为21万株·hm-2条件下减1/2氮+根瘤菌拌种处理(F3)产量最高.研究结果为本地区轮作条件下红小豆高产高效栽培技术提供理论依据.

为揭示不同耕作处理对土壤微生物、酶活性以及养分的影响,利用大豆为材料,采取两种不同耕作方式为主区,4种中耕方式为副区的裂区试验设计.结果 表明:旋耕处理的细菌数量在开花期较翻耕处理降低;旋耕处理的真菌数量在成熟期较翻耕处理提高;而放线菌数量在开花期,翻耕处理较旋耕处理提高,到结荚期却显著低于旋耕处理.翻耕处理的脲酶活性除了在鼓粒期低于旋耕处理,在其他生育期均高于旋耕处理;翻耕处理的土壤磷酸酶活性在结荚期、鼓粒期较旋耕处理提高;翻耕处理的土壤蔗糖酶活性在开花期较旋耕处理提高;翻耕处理在开花期与结荚期的过氧化氢酶(CAT)活性较旋耕处理提高.翻耕处理的速效磷含量较旋耕处理显著提高,速效钾含量旋耕处理较翻耕处理显著提高.在不同中耕措施中,土壤细菌数量在开花期RT1、RT2较RCK显著提高;真菌数量在成熟期PT1、PT2、PT3较PCK降低;各时期的放线菌数量PT2与RT2均较高.在各生育期,PT2、RT2的脲酶活性均较高,在开花期PT2较PCK和RT2较RCK显著提高;土壤磷酸酶活性PT2、RT2在各时期亦较高;土壤蔗糖酶活性在大豆成熟期不同处理均高于各自的CK;在大豆成熟期,PT1较PCK和RT1较RCK的CAT活性提高.不同中耕措施的土壤有机质含量除了RT2显著提高外,其他处理间差异不显著,而碱解氮、速效钾含量PT2、RT2均分别显著高于PCK、RCK.综上可知,PT2组合的耕作处理更有利于保护土壤微环境.

为揭示氮肥减施与接种不同根瘤菌对大豆光合作用及产量的影响,通过设置不同减氮量+接种根瘤菌处理,研究其对大豆净光合速率、蒸腾速率、气孔导度、胞间CO2浓度及大豆产量的影响.结果 表明:在开花期,T1(1/2施氮+拌种NF)、T2(1/2施氮+土壤施用NF)、T3(1/2施氮+拌种DF)处理的净光合速率相对于CK分别提高了50.4％、30.1％、29.6％.所有处理较常规施肥(CK)的蒸腾速率、胞间CO2浓度、气孔导度均有所上升,而大豆叶绿素含量较CK差异不显著,各处理的叶片干重较CK差异不显著,除T3处理外,各处理的茎干重较CK差异也不显著.进入结荚期后,T1、T2处理的胞间CO2浓度较CK分别提高了34.3％、47.0％,各处理净光合速率较CK均下降,而蒸腾速率、气孔导度均高于CK,除T4、T5外,叶绿素含量较CK差异不显著.除T2处理外,各处理的叶干重均低于CK,茎与荚皮干重较CK差异不显著,籽粒干重在所有减1/2施氮量+接种根瘤菌处理中均显著高于CK.在鼓粒期,各处理的净光合速率、蒸腾速率、胞间CO2浓度较CK差异不显著,气孔导度均高于CK,不施氮肥处理的叶绿素含量均显著低于CK.各处理的叶片干重均显著低于CK,但茎、荚皮干重与CK相比差异不显著,且籽粒干重有一定升高趋势,T3处理籽粒干重较CK提高了24.6％;在成熟期,1/2减氮+接种根瘤菌处理基本上均能提高大豆的产量及其构成因子,尤其是T3处理较CK产量提高9.75％.

为探讨周年不同氮磷调控施肥对大豆-玉米轮作周年产量及养分利用效率的影响,明确黑龙江垦区大豆-玉米轮作体系下最优的氮磷配施模式,于2017-2018年在黑龙江省九三管局鹤山农场科技园区进行小区试验,分别实施豆-玉轮作和玉-豆轮作,研究氮磷肥总用量不变条件下,大豆茬口减氮增磷和玉米茬口增氮减磷的调控模式对大豆-玉米轮作体系氮、磷、钾养分吸收利用效率及产量的调控效应.结果 表明:(1)与常规施肥相比,大豆茬口减施1/2氮肥、增施1/2玉米磷肥(S2处理)和玉米茬口增施1/2大豆氮肥、减施1/2磷肥(M2处理)的调控模式可提高大豆、玉米单季产量,显著增加轮作周年籽粒产量,与当地常规施肥相比,豆-玉轮作模式下周年产量增幅达10.05％,玉-豆轮作模式下周年产量增幅达13.40％;(2)不同氮磷调控处理的氮、磷、钾素积累总量、氮、磷、钾肥偏生产力、氮、磷、钾肥吸收效率均以轮作条件下大豆茬口S2处理和玉米M2处理最高,与常规施肥相比,豆-玉和玉-豆轮作下周年氮素积累总量、氮肥偏生产力和氮素吸收效率分别增加22.90％、10.09％、25.12％和11.10％、13.44％、1.39％;周年地上部磷素总积累量、磷肥偏生产力和磷素吸收效率分别增加8.24％、12.50％、7.58％和6.90％、13.45％、8.45％;周年地上部钾素总积累量、钾肥偏生产力和钾素吸收效率分别增加18.93％、12.50％、19.06％和0.52％、13.45％、0.71％.综合结果表明,在保证一个轮作周期施肥总量不变的情况下,大豆茬口减施1/2氮肥,增施1/2玉米磷肥和玉米茬口增施1/2大豆氮肥,减施1/2磷肥的调控模式有利于养分利用效率和产量的同步提高,可作为黑龙江垦区大豆-玉米轮作种植、高产高效施肥的优选模式.

为探明黑龙江垦区玉米-大豆轮作体系下的氮磷肥施用对玉米和大豆光合生产能力和产量的影响.采用小区试验法,于2016-2017年在黑龙江省九三管局分别实施玉-豆和豆-玉轮作,玉米茬口实施增氮减磷,大豆茬口实施减氮增磷,使一个轮作周年内氮磷肥施用总量一致.结果表明:2016年玉-豆轮作下玉米实施增氮减磷处理(MT2),与常规施肥(MCK)相比,提高了玉米叶片SPAD值、叶片的净光合速率、气孔导度和蒸腾速率,增加了乳熟期营养器官和穗干重,显著提高了玉米产量,MT2处理较MCK处理增产4.45％(P ＜0.05);2017年玉-豆轮作下大豆实施减氮增磷,与常规施肥相比,各处理均提高叶片的光合速率,增加了鼓粒初期和鼓粒盛期营养器官干物质积累量,产量均有所增加,但未达显著水平.2016年豆-玉轮作下大豆实施减氮增磷方案,与常规施肥相比,各处理均降低叶片SPAD、叶片的光合速率、大豆营养器官的干物质积累量,降低了大豆产量,但未达显著水平;2017年豆-玉轮作下玉米实施增氮减磷,与常规施肥相比,各处理提高了叶片SPAD、光合速率、大喇叭口期后的玉米干物质积累量和玉米产量,其中,MT2与MCK相比增加12.65％ (P ＜0.05).2年试验表明,在总施肥量不变的情况下,大豆玉米轮作体系下大豆茬口减50％的大豆氮、增50％的玉米磷,玉米茬口增50％的大豆氮、减50％的玉米磷处理可提高轮作周期的叶片的光合生产能力,显著提高玉米产量,同时保证大豆产量不降低,使轮作周期总产量提高.本研究结果可为黑龙江垦区玉米-大豆轮作高效施肥提供理论依据.

Hundred-seed weight is an important yield component and has positive relationship with soybean yield under certain conditions. The genetic gain of 100-seed weight based on traditional breeding or markers assisted-selection is limited because it is controlled by plenty of small effect genes. Genomic selection offers an approach to accelerate the soybean 100-seed weight breeding. However, the effect of population structure on soybean 100-seed weight prediction accuracy has not been elaborated. In our study 280 soybean varieties with phenotypic data evaluated in multi-location in 2008–2012 and 5361 SNPs genotype were used to explore the effect of population structure on 100-seed weight prediction accuracy. The best linear unbiased prediction of 100-seed weight of each variety was calculated according to mixed linear model. Ridge regression best linear unbiased prediction and five-fold cross validation were used to estimate the 100-seed weight prediction accuracy. Our research showed that the range of 100-seed weight, which was from –0.15 to +0.75. Hundred-seed weight prediction accuracy was affected by population struc-ture significantly. The prediction accuracy within a subset (+0.24 to +0.75) was higher than that between subsets (-0.15 to +0.29). When the genetic distance between subsets increased from 0.1566 to 0.2201, the 100-seed weight prediction accuracy was de-creased by 27.87％. Compared with random sampling training population, the training population composed based on genetic structure improved 100-seed weight prediction accuracy by 2.34％. In summary, we are clear about the soybean 100-seed weight genomic selection accuracy and the effect of population structure on genomic selection accuracy. The genomic selection is an efficient method to improve the soybean breeding.

In order to demonstrate the effect of conventional tillage system with topsoil treatment on the soil physical properties and soybean yield,adopting the method of regional contrast,setting two treatments (T1 represents local conventional tillage measures,T2 represents conventional tillage measures + topsoil soil crushing treatment) to analyze the influence on soil temperature and humidity,the bulk density,porosity,water stability,the aggregate in 0-30 cm soil depth and soybean yield.The results showed that T2 treatment significantly decreased 0-10 cm soil bulk density with a decline of 6％ to 13.8％,significantly increased the porosity of soil layer between 0-10 cm,with 3.83％ to 8.40％,reduced 5-15 cm soil temperature with a decline of 0.2 to 1.3 centigrade,improve 5-15 cm soil moisture with an increase from 0.1％ to 1.5％,significantly increase the number of large aggregate (R ＞0.25 mm) by 9.0％ to 20.3％.The mean weight diameter(MWD) and the geometric mean diameter(GMD) of soil water stability agglomeration increased by 4.25％ to 6.58％ and 28.4％ to 30.3％ respectively,while soybean yield increased by 6.24％.The results showed that topsoil crushing treatment could reduce topsoil bulk density,increase topsoil porosity,increase soil bulk aggregate number,increase soil water stability and provide a better soil environment for crop growth.

为研究外源褪黑素对干旱胁迫下大豆的缓解作用,促进褪黑素在生产实际中的应用,本试验以大豆抗线9为供试品种,采用盆栽控水的方式模拟干旱胁迫,设置不同浓度褪黑素叶面喷施处理,研究外源褪黑素对干旱胁迫下大豆幼苗生长的调控效应,为实际生产提供理论基础和技术参考.结果表明:外源褪黑素可显著缓解干旱胁迫对大豆幼苗生长的抑制作用,与干旱胁迫相比,干旱胁迫下喷施100和200μmol·L-1褪黑素处理促进叶面积和干物质积累总量,分别平均提高了8.04％和9.05％、6.76％和9.32％、13.89％和11.20％;显著提高了叶片光合参数、叶绿素荧光参数和相对含水量,其中Pn在第7和第14天分别提高了22.88％和54.57％,39.72％和57.53％,Tr分别提高了37.01％和18.99％,59.65％和45.17％;提高了抗氧化酶活性和渗透调节物质含量,降低了膜脂过氧化水平,其中SOD活性分别提高了41.73％和23.51％,19.77％和15.18％,MDA分别降低了37.47％和26.29％,33.68％和19.25％.综上所述,外源褪黑素可以提高干旱胁迫下大豆幼苗光合参数和叶绿素荧光参数,提高抗氧化酶活性进而促进ROS的清除,提高渗透调节物质含量有利于叶片保持较高的相对含水量,降低膜脂过氧化程度,从而提高大豆幼苗耐旱能力.

试验于2016年在黑龙江省农垦总局北安分局建设农场科技园区进行,以“合丰50”为材料,试验采用大区对比法,设置2个处理(T1:当地常规耕作措施;T2:当地常规耕作措施+表土破碎处理),研究2种表土处理方式对0～30 cm土壤温湿度、水稳定性团聚体及产量的影响.结果表明,T2处理增加5 cm和15 cm土壤湿度,增幅0.1％～1.5％,降低5 cm和15 cm土壤温度,降幅0.1～1.1℃,提高0～10 cm和10～20 cm＞5 mm、5～2 mm和2～1 mm粒级的团聚体含量和大团聚体(R＞0.25 mm)数量,增加0～10 cm和10～20 cm土层土壤水稳定性团聚体的平均质量直径(MWD)与几何平均直径(GMD),增加产量6.25％.结果证明,T2处理促进0～10 cm和10～20 cm土壤团聚体的形成,增加土壤大团聚体数量,增加土壤水稳定性,为作物的生长提供较良好的土壤环境;在20～30 cm土层处理间没有显著差异.

为了研究适合风沙土区的耕作方式,采用春旋地、打茬播种、原垄卡种及秋起垄四种不同整地方式进行对比试验.结果表明:耕作措施对土壤水分产生较大影响.其中,原垄卡种处理表现较好,保墒效果依次是原垄卡种>秋起垄>打茬播种>春旋地.原垄卡种处理的土壤温度低于其他处理.比较各项大豆生育性状指标,综合表现最好的是原垄卡种,最差的是春旋地处理.原垄卡种处理的产量最高,比秋起垄处理增加了16.7%,比春旋地及打茬播种处理增加了23.5%.

以高油型东农47和高蛋白型东农48大豆品种为试验材料,采用沙培方法,研究高油型和高蛋白型大豆品种鼓粒期不同器官可溶性糖含量、蔗糖含量和果糖含量的积累规律.结果表明:东农47鼓粒期根系、叶片和荚皮的可溶性糖含量均呈上升趋势,茎秆的可溶性糖含量呈先升后降趋势,东农48叶片和荚皮的可溶性糖含量均呈双峰曲线变化规律,茎秆可溶性糖含量与东农47变化规律一致;东农47鼓粒期各器官和东农48鼓粒期叶片、茎秆和根系的蔗糖含量变化规律均呈先升后降趋势,且峰值都在鼓粒后第12天;东农47根系的果糖含量呈上升趋势,茎秆和叶片呈先下降再上升后下降趋势,荚皮呈先上升再下降后上升趋势,东农48除根系果糖含量呈上升趋势外,其它器官均呈先升后降趋势.高蛋白型东农48鼓粒期可溶性糖、果糖含量较高油型东农47高.高油型东农47鼓粒期蔗糖含量较高蛋白型东农48高.

In order to obtain high yield and photosynthetic utilization rate maize hybrids, and develop the functional markers which associated with 10 yield and photosynthetic traits (leaf number of plant, chlorophyll content of three-ear-leaves, leaf area of ear leaf, leaf area of three-ear-leaves, leaf area index, plant height, ear height, ear length, row number of ear and 100 seed weight), 64 pairs of SSR markers were used to genotype the population of 257 maize inbred lines, analyzed the linkage disequilibrium loci and population structure, and determine the contribution rate of markers to phenotypic traits. The results showed that: (1) SSR markers displayed a certain extent of linkage disequilibrium (LD) in the public map. (2) Genetic structure analysis of SSR data demonstrated that the gene population can be divided into 5 subgroups. (3) 18 marker loci were identified to associate with 10 traits, in which 4 loci concentrated in chromosome 9. Seven marker loci were found to associated with 5 photosynthesis traits (leaf number of plant, chlorophyll content of three-ear-leaves, leaf area of ear leaf, leaf area of three-ear-leaves, leaf area index), which were bnlg439, bnlg2291, umc1524, bnlg1154, umc1545, umc1231 and bnlg1450. Seven loci were identified to associated with 5 yield traits (plant height, ear height, ear length, row number of ear and 100 seed weight), which were bnlg1175, umc1946, umc1496, bnlg249, umc2084, bnlg1191 and umc2122. There were other 4 markers loci (umc1065, phi116, bnlg162, phi065) were found associated with both yield traits and photosynthesis traits. The contribution rates of any locus to phenotypic date range from 0.0566 to 0.2145. Our results indicated that SSR marker could be useful for genotyping the population of maize inbred lines. Correlation analysis was useful to identify the markers which associated with phenotypic traits, which can be used for molecular maker assisted selection to improve the breeding efficiency. (C) 2017 Friends Science Publishers

Plant height is closely related to seed yield of soybean. The goal of this study was to identify important loci affecting soybean plant height using meta-analysis based on a reference physical map. Plant height related to QTLs was mapped across eight years with a RIL population by WinQTLCart v2.5. 182 QTLs related to plant height of soybean from database and our research were collected, and each QTL was projected onto the soybean physical map by software BioMercator v2.1. The confidence interval of meta-QTL ranged from 0.09 to 5.07Mb, and the mean phenotypic variance ranged from 4.9% to 73.0%. Furthermore, 4,259 candidate genes were located in these consensus QTLs, and 40 of them were involved in the plant growth and stem elongation and annotated as plant hormone signal transduction (pathway ID ko04075) in KEGG pathway. These results would lay a foundation for fine mapping of QTLs/genes related to plant height and marker-assisted selection for breeding in soybean.

基于NCBI网站下载获得的大豆AK基因cDNA序列设计特异引物,以大豆品种东农42总RNA为模板,通过RT-PCR获得约1 690 bp cDNA片段,经序列比对认定为AK基因序列.以19个赖氨酸和蛋氨酸含量特殊的大豆品种为材料,采用相同方法在RNA中进行扩增,并对产物测序,利用软件对所得序列进行分析.结果显示:在不同的大豆品种中AK基因的核酸序列存在两种变异方式,第一种是在336 bp产生1个T碱基突变的基因序列,第二种是在1 369～1374bp处出现“CAAGTG”6个碱基插入的序列;在蛋白质水平上,主要是在456 ～457个氨基酸处存在A和S两个氨基酸插入突变.AK基因结构完整,其编码的蛋白产物具有AA_kinase、Carbamate kinase-like、Aspartate kinase和ACT保守结构域.本研究首次对大豆中AK基因多样性进行了分析,为大豆天冬氨酸代谢途径其它相关酶基因的研究提供了理论依据,也为大豆AK基因在植物基因工程等领域的研究和应用奠定了良好的基础.

The concentration of protein in soybean is an important trait that drives successful soybean quality. A recombinant inbred line derived from a cross between the Charleston and Dongnong594 cultivars was planted in one location across 10 years and two locations across 5 years in China (20 environments in total), and the genetic effects were partitioned into additive main effects, epistatic main effects and their environmental interaction effects using composite interval mapping and inclusive composite interval mapping models based on a high-density genetic map. Ten main-effect quantitative trait loci (QTLs) were identified on chromosomes 3, 6, 7, 13, 15 and 20 and detected in more than three environments, with each of the main-effect QTLs contributing a phenotypic variation of around 10 %. Between the intervals of the main-effect QTLs, 93 candidate genes were screened for their involvement in seed protein storage and/or amino acid biosynthesis and metabolism processes based on gene ontology and annotation information. Furthermore, an analysis of epistatic interactions showed that three epistatic QTL pairs were detected, and could explain approximately 50 % of the phenotypic variation. The additive main-effect QTLs and epistatic QTL pairs contributed to high phenotypic variation under multiple environments, and the results were also validated and corroborated with previous research, indicating thatmarker-assisted selection can be used to improve soybean protein concentrations and that the candidate genes can also be used as a foundation data set for research on gene function.

Genomic selection is a promising molecular breeding strategy enhancing genetic gain per unit time. The objectives of our study were to (1) explore the prediction accuracy of genomic selection for plant height and yield per plant in soybean [Glycine max (L.) Merr.], (2) discuss the relationship between prediction accuracy and numbers of markers, and (3) evaluate the effect of marker preselection based on different methods on the prediction accuracy. Our study is based on a population of 235 soybean varieties which were evaluated for plant height and yield per plant at multiple locations and genotyped by 5361 single nucleotide polymorphism markers. We applied ridge regression best linear unbiased prediction coupled with fivefold cross-validations and evaluated three strategies of marker preselection. For plant height, marker density and marker preselection procedure impacted prediction accuracy only marginally. In contrast, for grain yield, prediction accuracy based on markers selected with a haplotype block analyses-based approach increased by approximately 4 % compared with random or equidistant marker sampling. Thus, applying marker preselection based on haplotype blocks is an interesting option for a cost-efficient implementation of genomic selection for grain yield in soybean breeding.