Introgression of chromosome 6PL terminal segment from Agropyron cristatum to increase both grain number and grain weight in wheat

Agropyron cristatum(2n=4x=28,PPPP),which harbours many high-yield and disease-resistance genes,is a promising donor for wheat improvement.Narrow genetic diversity and the trade-off between grain weight and grain number have become bottlenecks for increasing grain yield in wheat.In this study,a novel translocation line,WAT650l,was derived from the chromosome 6P addition line 4844–12,which can simultaneously increase both grain number per spike(GNS)and thousand-grain weight(TGW).Cytological analysis and molecular marker analysis revealed that WAT650l was a 5BL.5BS-6PL(bin 12–17)translocation line.Assessment of agronomic traits and analysis of the BC4F2 and BC5F2 populations suggested that the 6PL terminal chromosome segment in WAT650l resulted in increased grain number per spike(average increased by 14.07 grains),thousand-grain weight(average increased by 4.31 g),flag leaf length,plant height,spikelet number per spike and kernel number per spikelet during the two growing seasons of 2020–2021 and 2021–2022.Additionally,the increased GNS locus and high-TGW locus of WAT650l were mapped to the bins 16–17 and 12–13,respectively,on chromosome 6PL by genetic population analysis of three translocation lines.In summary,we provide a valuable germplasm resource for broadening the genetic base of wheat and overcoming the negative relationship between GNS and TGW in wheat breeding.

Effect of delayed sowing on grain number, grain weight, and protein concentration of wheat grains at specific positions within spikes

Delays in sowing have significant effects on the grain yield,yield components,and grain protein concentrations of winter wheat.However,little is known about how delayed sowing affects these characteristics at different positions in the wheat spikes.In this study,the effects of sowing date were investigated in a winter wheat cultivar,Shannong 30,which was sown in 2019 and 2020 on October 8(normal sowing)and October 22(late sowing)under field conditions.Delayed sowing increased the partitioning of ^(13)C-assimilates to spikes,particularly to florets at the apical section of a spike and those occupying distal positions on the same spikelet.Consequently,the increase in grain number was the greatest for the apical sections,followed by the basal and central sections.No significant differences were observed between sowing dates in the superior grain number in the basal and central sections,while the number in apical sections was significantly different.The number of inferior grains in each section also increased substantially in response to delayed sowing.The average grain weights in all sections remained unchanged under delayed sowing because there were parallel increases in grain number and ^(13)C-assimilate partitioning to grains at specific positions in the spikes.Increases in grain number m^(–2) resulted in reduced grain protein concentrations as the limited nitrogen supply was diluted into more grains.Delayed sowing caused the greatest reduction in grain protein concentration in the basal sections,followed by the central and apical sections.No significant differences in the reduction of the grain protein concentration were observed between the inferior and superior grains under delayed sowing.In conclusion,a 2-week delay in sowing improved grain yield through increased grain number per spike,which originated principally from an increased grain number in the apical sections of spikes and in distal positions on the same spikelet.However,grain protein concentrations declined in each section because of the increased grain number and reduced N uptake.

Characterization of a new hexaploid triticale 6D(6A) substitution line with increased grain weight and decreased spikelet number

Hexaploid triticale(×Triticosecale,AABBRR)is an important forage crop and a promising energy plant.Transferring D-genome chromosomes or segments from common wheat(Triticum aestivum)into hexaploid triticale is attractive in improving its economically important traits.Here,a hexaploid triticale 6D(6A)substitution line Lin 456 derived from the cross between the octoploid triticale line H400 and the hexaploid wheat Lin 56 was identified and analyzed by genomic in situ hybridization(GISH),fluorescence in situ hybridization(FISH),and molecular markers.The GISH analysis showed that Lin 456 is a hexaploid triticalewith 14 rye(Secale cereale)chromosomes and 28 wheat chromosomes,whereas non-denaturing fluorescence in situ hybridization(ND-FISH)and molecular marker analysis revealed that it is a 6D(6A)substitution line.In contrast to previous studies,the signal of Oligo-pSc119.2 was observed at the distal end of 6DL in Lin 456.The wheat chromosome 6D was associatedwith increased grain weight and decreased spikelet number using the genotypic data combined with the phenotypes of the F2 population in the three environments.The thousand-grain weight and grain width in the substitution individuals were significantly higher than those in the non-substitution individuals in the F2 population across the three environments.We propose that the hexaploid triticale 6D(6A)substitution line Lin 456 can be a valuable and promising donor stock for genetic improvement during triticale breeding.

The TaGW2‐TaSPL14 module regulates the trade‐off between tiller number and grain weight in wheat

IDEAL PLANT ARCHITECTURE1(IPA1)is a pivotal gene controlling plant architecture and grain yield.However,little is known about the effects of Triticum aestivum SQUAMOSA PROMOTER‐BINDING‐LIKE 14(TaSPL14),an IPA1 ortholog in wheat,on balancing yield traits and its regulatory mechanism in wheat(T.aestivum L.).Here,we determined that the T.aestivum GRAIN WIDTH2(TaGW2)‐TaSPL14 module influences the balance between tiller number and grain weight in wheat.Overexpression of TaSPL14 resulted in a reduced tiller number and increased grain weight,whereas its knockout had the opposite effect,indicating that TaSPL14 negatively regulates tillering while positively regulating grain weight.We further identified TaGW2 as a novel interacting protein of TaSPL14 and confirmed its ability to mediate the ubiquitination and degradation of TaSPL14.Based on our genetic evidence,TaGW2 acts as a positive regulator of tiller number,in addition to its known role as a negative regulator of grain weight,which is opposite to TaSPL14.Moreover,combinations of TaSPL14‐7A and TaGW2‐6A haplotypes exhibit significantly additive effects on tiller number and grain weight in wheat breeding.Our findings provide insight into how the TaGW2‐TaSPL14 module regulates the trade‐off between tiller number and grain weight and its potential application in improving wheat yield.

Identification and validation of stable quantitative trait loci for yield component traits in wheat

Grain weight and grain number are important yield component traits in wheat and identification of underlying genetic loci is helpful for improving yield.Here,we identified eight stable quantitative trait loci(QTL)for yield component traits,including five loci for thousand grain weight(TGW)and three for grain number per spike(GNS)in a recombinant inbred line population derived from cross Yangxiaomai/Zhongyou 9507 across four environments.Since grain size is a major determinant of grain weight,we also mapped QTL for grain length(GL)and grain width(GW).QTGW.caas-2D,QTGW.caas-3B,QTGW.caas-5A and QTGW.caas-7A.2 for TGW co-located with those for grain size.QTGW.caas-2D also had a consistent genetic position with QGNS.caas-2D,suggesting that the pleiotropic locus is a modulator of trade-off effect between TGW and GNS.Sequencing and linkage mapping showed that TaGL3-5A and WAPO-A1 were candidate genes of QTGW.caas-5A and QTGW.caas-7A.2,respectively.We developed Kompetitive allele specific PCR(KASP)markers linked with the stable QTL for yield component traits and validated their genetic effects in a diverse panel of wheat cultivars from the Huang-Huai River Valley region.KASP-based genotyping analysis further revealed that the superior alleles of all stable QTL for TGW but not GNS were subject to positive selection,indicating that yield improvement in the region largely depends on increased TGW.Comparative analyses with previous studies showed that most of the QTL could be detected in different genetic backgrounds,and QTGW.caas-7A.1 is likely a new QTL.These findings provide not only valuable genetic information for yield improvement but also useful tools for marker-assisted selection.

Natural variation in MORE GRAINS 1 regulates grain number and grain weight in rice

Grain yield is determined mainly by grain number and grain weight.In this study,we identified and characterized MORE GRAINS1(MOG1),a gene associated with grain number and grain weight in rice(Oryza sativa L.),through map-based cloning.Overexpression of MOG1 increased grain yield by 18.6%-22.3%under field conditions.We determined that MOG1,a bHLH transcription factor,interacts with OsbHLH107 and directly activates the expression of LONELY GUY(LOG),which encodes a cytokinin-activating enzyme and the cell expansion gene EXPANSIN-LIKE1(EXPLA1),positively regulating grain number per panicle and grain weight.Natural variations in the promoter and coding regions of MOG1 between Hap-LNW and Hap-HNW alleles resulted in changes in MOG1 expression level and transcriptional activation,leading to functional differences.Haplotype analysis revealed that Hap-HNW,which results in a greater number and heavier grains,has undergone strong selection but has been poorly utilized in modern lowland rice breeding.In summary,the MOG1-OsbHLH107 complex activates LOG and EXPLA1 expression to promote cell expansion and division of young panicles through the cytokinin pathway,thereby increasing grain number and grain weight.These findings suggest that Hap-HNW could be used in strategies to breed high-yielding temperate japonica lowland rice.

Natural variations of HvSRN1 modulate the spike rachis node number in barley

Grain number,one of the major determinants of yield in Triticeae crops,is largely determined by spikelet number and spike rachis node number(SRN).Here,we identified three quantitative trait loci(QTLs)for SRN using 145 recombinant inbred lines derived from a barley R90/1815D cross.qSRN1,the major-effect QTL,was mapped to chromosome 2H and explained up to 38.77%of SRN variation.Map-based cloning revealed that qSRN1 encodes the RAWUL domain-containing protein HvSRN1.Further analysis revealed that two key SNPs in the HvSRN1 promoter region(-2 kb upstream of the transcription start site)affect the transcript level of HvSRN1 and contribute to variation in SRN.Similar to its orthologous proteins OsLAX2 and ZmBA2,HvSRN1 showed protein–protein interactions with HvLAX1,suggesting that the LAX2–LAX1 model for spike morphology regulation may be conserved in Poaceae crops.CRISPR-Cas9-induced HvSRN1 mutants showed reduced SRN but increased grain size and weight,demonstrating a trade-off effect.Our results shed light on the role of HvSRN1 variation in regulating the balance between grain number and weight in barley.

Multivariate Cluster and Principle Component Analyses of Selected Yield Traits in Uzbek Bread Wheat Cultivars

Investigation of genetic diversity of geographically distant wheat genotypes is a useful approach in wheat breeding providing efficient crop varieties. This article presents multivariate cluster and principal component analyses (PCA) of some yield traits of wheat, such as thousand-kernel weight (TKW), grain number, grain yield and plant height. Based on the results, an evaluation of economically valuable attributes by eigenvalues made it possible to determine the components that significantly contribute to the yield of common wheat genotypes. Twenty-five genotypes were grouped into four clusters on the basis of average linkage. The PCA showed four principal components (PC) with eigenvalues > 1, explaining approximately 90.8% of the total variability. According to PC analysis, the variance in the eigenvalues was the greatest (4.33) for PC-1, PC-2 (1.86) and PC-3 (1.01). The cluster analysis revealed the classification of 25 accessions into four diverse groups. Averages, standard deviations and variances for clusters based on morpho-physiological traits showed that the maximum average values for grain yield (742.2), biomass (1756.7), grains square meter (18,373.7), and grains per spike (45.3) were higher in cluster C compared to other clusters. Cluster D exhibited the maximum thousand-kernel weight (TKW) (46.6).

Analysis of Yield Components of Japonica Rice Tong Jing 981 under Different Density and Fertilization Conditions

The yield and yield components of Japonica variety Tongjing 981 under different density and fertilization levels were studied through regression and correlation and path analysis. The results showed that the number of panicles per unit area, number of filled grains per panicle and 1 000-grain weight all had very significant yield increasing effects, and the number of panicles per unit area played a leading role. However, the yield increasing effects of the number of panicles per unit area and number of filled grains per panicle are equally important when the basic seedlings are more or the N fertilizer application rate is large. In practical production, a major factor should be determined among the yield components, and rational cultivation measures should be taken accordingly, to improve yield.

不同季秸秆还田对冬小麦不同穗粒位结实粒数和粒重的影响

为探讨安徽淮北平原砂姜黑土区长期秸秆连续全量还田对冬小麦穗部结实特性的影响,2021-2022年基于农业农村部华东地区作物栽培科学观测站13年的长期定位试验,比较分析了小麦单季秸秆全量粉碎覆盖还田(T1)、小麦玉米秸秆全量粉碎还田(T2)、玉米秸秆全量粉碎翻埋还田(T3)、小麦玉米秸秆全年不还田(CK)4个不同还田模式下小麦不同小穗位结实粒数及粒重的差异。结果表明,T1、T2、T3处理的主茎穗小穗结实总粒数较CK分别提高了21.21%、7.50%和12.55%;第2粒位(G2)结实粒数分别提高了7.71%、7.71%和5.79%;上部小穗结实粒数分别提高了51.41%、22.79%和31.36%,其G2结实粒数分别提高了30.95%、30.95%和23.09%,其中T1处理对小麦粒数的提升效果最好。不同季秸秆还田处理下小麦主茎穗及其G2粒重、分蘖穗及其第三粒位(G3)粒重均高于CK,T1、T2和T3处理的主茎穗粒重增幅分别为16.06%、4.14%和16.06%,分蘖穗增幅分别为9.86%、0.71%和8.87%;T1、T2和T3处理下主茎穗G2粒重增幅分别为20.69%、10.34%和17.24%,分蘖穗G3粒重4.55%、2.27%和6.82%,其中T1处理对粒重提升效果最好,其次是T3。综合来看,在安徽淮北平原砂姜黑土区长期秸秆还田能够提高小麦穗粒数和粒重,进而促进产量提升,其中T1处理对小麦结实粒数和粒重的提升效果最好,是适宜在该地区推广的秸秆还田模式。

Analysis of Influencing Factors on Yield of Seven Wheat Cultivars in Anhui Province

[Objective] The objective of this paper was to screen out suitable high- yielding cultivars and to understand the current yield performance of wheat in Anhui Province. In addition, the influencing factors on wheat yield were discussed to es- tablish suitable cultural practice. [Method] Main popularized cultivars and some new strains of wheat were selected as matedals and planted in the Funan Farm and Longkang Farm in 2009-2011. The yield stability and influencing factors on yield of wheat were discussed. [Resalt] In Anhui Province, the weather had a great influence on wheat yield, resulting in significant differences in wheat yield among different years. Drought was the main factor restricting the yield. [Conclusion] （1） It was easy to achieve high yield when the three influencing factors on wheat yield were coordi- nated. （2） The occurred drought disaster in 20tl was the main factor limiting the 1 000- grain weight and final yield of wheat. （3） Different cultivars showed different yield stabilities. Among the test wheat cultivars, two cultivars （Wanke 06290 and Yannong 19） showed good yield stability, while Xinfumai No.1 showed higher yield. （4） The three influencing factors played different roles in different cultivars. In the promotion process, the characteristics of wheat cultivars should be fully understood. To achieve high yield, integrating cultural practices is a necessity.

OsSPL18 controls grain weight and grain number in rice

Grain weight and grain number are two important traits directly determining grain yield in rice. To date,a lot of genes related to grain weight and grain number have been identified; however, the regulatory mechanism underlying these genes remains largely unknown. In this study, we studied the biological function of OsSPL18 during grain and panicle development in rice. Knockout (KO) mutants of OsSPL18exhibited reduced grain width and thickness, panicle length and grain number, but increased tiller number. Cytological analysis showed that OsSPL18 regulates the development of spikelet hulls by affecting cell proliferation. qRT-PCR and GUS staining analyses showed that OsSPL18 was highly expressed in developing young panicles and young spikelet hulls, in agreement with its function in regulating grain and panicle development. Transcriptional activation experiments indicated that OsSPL18is a functional transcription factor with activation domains in both the N-terminus and C-terminus, and both activation domains are indispensable for its biological functions. Quantitative expression analysis showed that DEP1, a major grain number regulator, was significantly down-regulated in OsSPL18 KO lines.Both yeast one-hybrid and dual-luciferase (LUC) assays showed that OsSPL18 could bind to the DEP1promoter, suggesting that OsSPL18 regulates panicle development by positively regulating the expression of DEP1. Sequence analysis showed that OsSPL18 contains the OsmiR156k complementary sequence in the third exon; 5?RLM-RACE experiments indicated that OsSPL18 could be cleaved by OsmiR156k. Taken together, our results uncovered a new OsmiR156k-OsSPL18-DEP1 pathway regulating grain number in rice.

Activity of Corn Silk at Different Days after Silk Emergence

This study was carried out to evaluate the changes in silk activity of two corn cultivars Xundan 518 and Yongyou 618 after silk emergence. Artificial pollination was conducted at different days after silk emergence, and the ear length, ear diameter,barren tip length, 100-grain weight, grain number per ear and grain weight per ear were measured at harvest. The results showed that with the delay of pollination, the number and weight of grains per ear increased at first, peaked at D2 to D4, and decreased subsequently; ear diameter and 100-grain weight showed a downward trend. Correlation analysis revealed that grain number per ear and grain weight per ear were most closely correlated. Rapid silk extrusion and long-lasting silk activity proved that the two corn cultivars Xundan 518 and Yongyou 618 are tolerant to high temperature.

药隔期倒春寒对小麦主茎穗不同穗粒位结实数与粒重的影响

在大田盆栽条件下利用智能超低温光照培养箱,对烟农19(YN19,抗倒春寒性强)和新麦26(XM26,抗倒春寒性弱)两个小麦品种于幼穗分化的药隔形成期进行4h·d-1的倒春寒模拟试验。设置2℃和-2℃两个低温胁迫水平,对照(CK)为10℃,以明确不同程度倒春寒胁迫对不同抗倒春寒性品种小麦主茎穗各穗粒位结实粒数及粒重的影响。结果表明:(1)各处理主茎穗不同小穗位的结实粒数和粒重均呈先升后降的二次曲线变化。(2)倒春寒胁迫导致小麦主茎穗不同穗粒位结实粒数显著降低,且降幅随胁迫程度的加重而增大。2℃和-2℃胁迫处理下YN19主茎穗的下、中、上部小穗总粒数分别显著降低40.74%、18.75%、35.00%和70.37%、32.50%、15.00%(P<0.05);XM26分别显著降低62.50%、7.87%、20.00%和100%、42.22%、100%(P<0.05)。(3)轻度倒春寒胁迫(2℃)导致小麦主茎穗粒重降低,重度倒春寒胁迫(-2℃)下粒重反而会因穗粒数的大幅降低而有所上升。与对照相比,2℃胁迫处理下YN19主茎穗各小穗粒重降幅在2.93%~47.53%,XM26降幅为19.72%~49.96%(P<0.05);-2℃胁迫处理下YN19主茎穗各小穗粒重增幅在20.57%~60.84%,XM26增幅为1.20%~42.78%(P<0.05)。(4)倒春寒胁迫导致两品种小麦主茎穗不同小穗位总粒重较CK降低。YN19在2℃和-2℃胁迫处理下,下部和中部小穗总粒重较CK分别显著降低49.49%、28.99%和65.76%、29.47%,上部小穗在-2℃胁迫处理下总粒重较CK显著降低23.09%(P<0.05);XM26下、中、上部小穗总粒重较CK分别显著降低69.76%、28.61%、20.02%和100%、42.33%、100%(P<0.05)。综上所述,倒春寒对小麦主茎穗不同穗粒位结实粒数和粒重均会产生不利影响,对小麦穗位的危害表现为下部>上部>中部,对小麦粒位的危害表现为第3粒位>第1粒位>第2粒位。本试验分析认为,倒春寒对小麦主茎穗结实粒数的影响大于对粒重的影响,影响程度随倒春寒胁迫程度的加重而增大。无论是结实粒数还是粒重均表现为下部小穗受害程度最大,即弱势小穗和弱势粒受倒春寒影响更大。药隔期倒春寒主要通过减少主茎穗上部小穗和下部小穗的穗粒数,降低弱势粒粒重,最终导致小麦减产。综合比较,品种YN19的受害程度轻于XM26,YN19抗倒春寒能力更强,所以选用抗倒春寒性强的小麦品种是生产中降低倒春寒危害的重要措施。

不同品种(系)彩色小麦干物质积累转运和产量形成分析

为明确不同品种(系)彩色小麦主要农艺性状的特征及其与籽粒产量的相关关系,筛选出适宜鲁东地区栽培的彩色小麦品种。于2020-2022年2个冬小麦生长季,选用4个紫色小麦品种(系)青研紫麦1号(QYZ-1)、QYZ-2、山农紫麦1号(SNZM1)和农大3753(ND3753),2个蓝色小麦品系20064和20072以及普通白粒小麦品种济麦22(JM22,对照品种)为试验材料,系统研究了不同品种(系)彩色小麦的旗叶SPAD值、叶面积指数、干物质积累与转运、产量及其构成因素等方面的差异,和各农艺性状的稳定性以及产量可持续性。结果表明,各彩色小麦品种产量、千粒质量、开花期叶面积指数、花后SPAD值、开花期干物质积累量、成熟期干物质积累量、花后干物质积累量及收获指数均低于普通白粒小麦品种济麦22。各彩色小麦品种(系)间比较,紫色小麦QYZ-1产量显著高于其他彩色小麦品种(系),单位面积粒数与QYZ-2无显著差异,但其千粒质量显著高于QYZ-2;紫色小麦QYZ-1开花期上三叶叶面积指数显著高于蓝色小麦品系及ND3753,紫色小麦QYZ-1花后旗叶SPAD、成熟期干物质积累量、花后干物质积累量、花前干物质转运量和收获指数均高于其余彩色小麦品种(系);与其他品种(系)比较,JM22和QYZ-1各农艺性状的变异系数(CV)均较小,彩色小麦间比较,QYZ-1的产量均值和产量可持续性指数(SYI)均较高。另外,相关分析表明,产量分别与开花期干物质积累量、成熟期干物质积累量、花后干物质积累量、花前干物质转运量、收获指数、旗叶花后28 d SPAD值、开花期全绿叶叶面积指数和千粒质量呈极显著的正相关关系。综合2 a的结果,表明QYZ-1具有适宜的叶面积指数,并维持了较高的花后旗叶SPAD值,花后旗叶的衰老较慢,开花-成熟时间较长,协同提高了花后干物质积累量和花前干物质转运量、成熟期干物质积累量和收获指数以及单位面积粒数和千粒质量,表现出较高的产量。综上所述,青研紫麦1号产量稳定且可持续性较好,是适宜鲁东地区栽培的彩色小麦品种。

河南省退耕还林对粮食生产与农民增收的影响

【目的】探讨河南省2011—2020年10市(区)退耕还林对粮食生产与农民增收效益的影响。【方法】选取2011—2020年河南省退耕还林10个重点市(区)数据,采用熵权-TOPSIS模型,建立退耕还林影响下粮食生产与农民增收的指标体系,评价其经济效益。【结果】2011—2020年,河南省各退耕还林标准地区通过退耕还林,对省内粮食生产与农民增收工作整体上都起到了正向的效果,但还存在继续完善的空间。【结论】河南省退耕还林工作成效显著,但仍需进一步完善配套政策,实现更高的经济效益。

补灌量和覆盖量耦合变化下旱地春小麦叶面积指数对产量的影响

免耕覆盖中补灌量和秸秆覆盖量耦合变化下春小麦叶面积指数对产量有较大影响。以甘肃省定西市安定区1979—2019年历史气象数据为基础,运用APSIM模型对补灌量与覆盖量耦合变化下旱地春小麦的叶面积指数、产量及其构成因素进行模拟,并采用DPS软件进行分析,研究补灌量和覆盖量耦合下旱地春小麦叶面积指数对产量的影响机制。结果表明,在试验设计范围内,不同春小麦叶面积指数对春小麦千粒质量的影响效应在开花-灌浆期为向上的二次抛物线变化;其他时期,不同春小麦叶面积指数对春小麦产量和千粒质量的影响效应为向下的二次抛物线变化,不同春小麦叶面积指数对春小麦籽粒数的影响效应为向上的二次抛物线变化。试验设计范围内,各个时期春小麦千粒质量均未出现阈值,分蘖-拔节期,春小麦产量未出现阈值,春小麦籽粒数出现阈值,春小麦叶面积指数为1.72时春小麦籽粒数出现最小值为8716.59粒/m^(2);其他时期,春小麦产量和籽粒数出现阈值,在春小麦叶面积指数为0.94、2.31、1.67、1.18、1.24和0.79时春小麦产量出现最大值为3818.71、3827.06、3851.4、3904.35、3819.03和3853.72 kg/hm^(2)。春小麦叶面积指数为0.77、2.01、1.44、1.07、1.00和0.70时春小麦籽粒数出现最小值为9579.34、8745.26、9638.01、9050.71、8554.04和9038.38粒/m^(2)。春小麦叶面积指数对产量和千粒质量呈正效应,对籽粒数呈负效应。合理调节春小麦叶面积指数,可以促进透光性速率的提高、光合产物的产生,对春小麦产量的提高具有积极意义。

A Pyramid Breeding of Eight Grain-yield Related Quantitative Trait Loci Based on Marker-assistant and Phenotype Selection in Rice(Oryza sativa L.)

1000-Grain weight and spikelet number per panicle are two important components for rice grain yield. In our previous study, eight quantitative trait loci （QTLs） conferring spikelet number per panicle and 1000-grain weight were mapped through sequencing-based genotyping of 150 rice recombinant inbred lines （RILs）. In this study, we validated the effects of four QTLs from Nipponbare using chromosome segment substitution lines （CSSLs）, and pyramided eight grain yield related QTLs. The new lines containing the eight QTLs with positive effects showed increased panicle and spikelet size as compared with the parent variety 93-11. We further proposed a novel pyramid breeding scheme based on marker-assistant and phenotype selection （MAPS）. This scheme allowed pyramiding of as many as 24 QTLs at a single hybridization without massive cross work. This study provided insights into the molecular basis of rice grain yield for direct wealth for high-yielding rice breeding.

不同大豆品种与酒用高粱间作的产量性状分析

文章研究了安豆10、渝豆11号、黔豆7号、黔豆10号、油春1204等5个不同大豆品种与酒用高粱间作的产量性状,发现黔豆7号产量最高,单产119.72 kg/0.067 hm^(2)。其次油春1 204单产达114.45 kg/0.067 hm^(2),再次是黔豆10号单产106.9 kg/0.067 hm^(2),最后是渝豆11号和安豆10号。

小麦结实粒数、粒重和品质的小穗位和粒位效应

【目的】研究小麦不同小穗位和粒位的穗结实粒数、粒重和品质变化规律。【方法】通过田间试验系统研究穗结实粒数相近,粒重和品质不同的3个小麦品种的结实粒数、粒重和品质的小穗位和粒位效应。【结果】3个小麦品种不同小穗位籽粒结实粒数、小穗千粒重、粒重、蛋白质含量、干面筋、沉降值、吸水率、稳定时间、评价值和软化度均呈现二次曲线变化趋势分布,第1粒位、第2粒位和第3粒位的粒重及品质也随小穗位的变化呈二次曲线形式,表现出籽粒发育的近中优势。第1粒位和第2粒位的粒重相近,都高于第3结实粒位;第2粒位增产潜力较大,是粒重变化的主要因素;临优2018和临优2069第2粒位,临优145第1粒位的蛋白质含量、干面筋和沉降值较高且变异较大,增质潜力较大,是品质变异的主要因素。【结论】在小麦育种和栽培中,对于每小穗最多结实3粒籽粒的品种,应尽量减少小花位数,来保持小麦籽粒品质的稳定性和一致性。