Fine Mapping of qTGW3-1,a QTL for 1000-Grain Weight on Chromosome 3 in Rice

The QTL qTGW3-1 was located on chromosome 3 of rice （Oryza sativa L.） and associated with the 1 000-grain weight （TGW） according to the result of our earlier study. With the objective of fine mapping of this locus, we developed a F2 population consisting of 3 428 plants derived from the cross between TGW-related near isogenic line DL017 （BC3F4 generation of GSL 156×Nipponbare） and the recurrent parent Nipponbare. Using six microsatellites, this QTL was delimited between RM5477 and RM6417. Markers MM 1455 and MM 1456 within this region were used for further mapping of this QTL. Finally, qTGW3-1 was fine-mapped into a 89-kb interval between RM5477 and MM1456, which locates in the BAC clone AC107226 harboring five putative candidate genes.

Mapping of qTGW1.1,a Quantitative Trait Locus for 1000-Grain Weight in Rice (Oryza sativa L.)

1000-grain weight （ TGW） is one ot the three component traits ot the grain yiela in rice （Oryza sativa L）. This study was conducted to validate and fine-map qTGWl. 1, a minor QTL for TGW which was previously located in a 3.7-Mb region on the long arm of rice chromosome 1. Five sets of near isogenic lines （NILs） were developed from two BC2F4 populations of the indica rice cross Zhenshan 973/Milyang 46 The NIL sets consisted of two homozygous genotypic groups differing in the regions RM11448-RM11522, RM11448-RM11549, RM1232-RM11615, RM11543-RM11554 and RM11569-RM11621, respectively. Four traits, including TGW, grain length, grain width and heading date, were measured. Phenotypic difference between the two genotypic groups in each NIL population was analyzed using SAS procedure GLM. Significant QTL effects were detected on TGW with the Zhenshan 97 allele increasing grain weight by 0.12 g to 0.14 g and explaining 8.30% to 15.19% of the phenotypic variance. Significant effects were also observed for grain length and width, whereas no significant effect was found for heading date. Based on comparison among the five NILs on the segregating regions and the results of QTL analysis, qTGWl. 1 was delimited to a 376.9-kb region flanked by DNA markers Wn28382 and RMl1554. Our results indicate that the effects of minor QTLs could be steadily detected in a highly isogenic background and suggest that such QTLs could be utilized in the breeding of high-yielding rice varieties.

Correlation Analysis of Rice Seed Setting Rate and Weight of 1 000-Grain and Agro-Meteorology over the Middle and Lower Reaches of the Yangtze River,China

The purpose of this study is to reveal the effects of historic climate change on rice yield over the middle and lower reaches of the Yangtze River, China, and to better adapt to climate change in the future. This study presents the relation of temperature and precipitation and rice components from 1981 to 2003 at 48 early rice stations and 30 middle rice stations. It focuses on an analysis of three stages： flowering, pre-milk, and late milk. The results show that mean maximum temperature and mean daily precipitation at the stages of flowering and pre-milk are most related to early rice yield. Yield change of middle rice is mainly because of mean precipitation change at the flowering stage. Furthermore, percentage of undeveloped grain increases as mean maximum temperature rises at the flowering stage. Over-precipitation in the reproductive stage is a major reason for reduction in yield of early rice. Consecutive rainfall and continuous high temperature can have negative effects on middle rice yield. Global warming would affect middle rice more seriously than early rice.

小麦E3泛素连接酶基因TaSINA-3A与多种环境下的株高和千粒重相关

E3泛素连接酶SINA(seven in absentia)家族参与植物的生长发育、免疫共生并响应逆境胁迫。本研究克隆了位于小麦染色体3A上的TaSINA-3A基因,其基因组序列长度为3897 bp,其中启动子区为2001 bp,基因序列为1896 bp,编码244个氨基酸,在50~91位氨基酸处有一个RING(really interesting new gene)保守结构域。RT-qPCR结果显示,TaSINA-3A基因在小麦的各个发育阶段的不同组织中均有表达。序列多态性分析表明,在TaSINA-3A的启动子区存在33个SNP(single nucleotide polymorphism)位点,编码区有4个SNP位点。基于启动子区的变异位点SNP-159、SNP-418和SNP-1286开发分子标记,扫描小麦自然群体,并与表型性状进行关联分析。结果表明,标记CAPS-159与多种环境下的株高和倒二节长显著相关,SNP-159-C是倒二节较短的矮秆等位变异,标记dCAPS-418分别与多种环境下的穗长和千粒重显著关联,SNP-418-A是长穗、高千粒重的优异等位变异;TaSINA-3A负调控穗和籽粒的发育,TaSINA-3A的表达可能受到MYC转录因子的抑制;在我国小麦育种进程中SNP-418-A受到正向选择,在育成品种中的频率逐步增加,但尚未充分利用。研究结果为深入探讨小麦株高、倒二节长及产量的形成机制提供参考,并为培育高产稳产广适新品种提供了基因资源。

基于高密度遗传图谱定位水稻籽粒性状QTL

籽粒性状直接影响水稻的产量和品质,因此,解析水稻籽粒性状的遗传机制对提高水稻产量和品质至关重要。本研究以籽粒性状差异较大的穞稻和广百香占为亲本构建定位群体,利用水稻1 K mGPS SNP芯片对定位群体进行基因分型,构建了包含770个Bin标记的高密度遗传图谱,通过QTL定位分析,最终鉴定出17个调控籽粒性状的QTLs,其中粒长QTL 4个,粒宽QTL 3个,粒厚QTL 3个,长宽比QTL 2个,千粒重QTL 5个,LOD值介于2.55~42.44之间,表型贡献率介于4.73%~29.63%之间。在这17个QTLs中,9个为已知粒型基因位点,8个可能是新鉴定位点,分别为粒长qGL6,粒宽qGW5、qGW10和qGW12,粒厚qGT10,长宽比qGLWR5-2,千粒重qTGW10和qTGW11。根据新发现粒宽QTL(qGW5)定位区间内的基因注释、与拟南芥的同源基因比对、时空表达分析、激素响应分析和序列分析,最终筛选到1个编码CCCH类锌指蛋白的调控水稻粒宽的候选基因Os05g0195101。本研究为进一步开展水稻籽粒性状基因的克隆和遗传调控的解析奠定了基础。

不同麦类作物籽粒灌浆特性研究

为研究不同麦类作物籽粒的灌浆特性,以小麦品种‘宁麦13’、大麦品种‘龙啤1号’和青稞品种‘昆仑15号’为试材,利用Logistic模型对籽粒灌浆过程进行拟合,分析了3种作物粒重增长进程和灌浆参数的差异。结果表明:小麦、大麦和青稞千粒重分别为51.60、49.01、46.43 g/(1000grain),三者之间差异显著(P<0.05)。小麦籽粒有效灌浆时间为45.89 d,分别比大麦和青稞长9.84 d和3.59 d(P<0.05);小麦粒重快增期和缓增期持续时间显著长于大麦和青稞,青稞与大麦无显著性差异。大麦籽粒平均灌浆速率为1.37 g/(1000grain·d),高于小麦和青稞18.10%和24.55%(P<0.05);大麦籽粒粒重快增期灌浆速率、缓增期灌浆速率和最大灌浆速率显著高于小麦和青稞,青稞与小麦无显著性差异,但大麦在快增期灌浆速率下降最快。可见,小麦与大麦、青稞之间粒重的差异主要取决于籽粒灌浆持续时间,大麦与青稞之间粒重的差异主要取决于籽粒的灌浆速率。

Mapping of QTLs Related to Grain Weight Using Chromosome Single Segment Substitution Lines in Rice

Grain weight, one of the major factors determining rice yield, is a typical quantitative trait control ed by multiple genes. With Guangluai 4 as recipient and Nipponbare as donor, a population of 119 chromosome single segment substitution lines had been developed. Correlation analysis between grain weight and grain shape by SPSS revealed that 1 000-grain weight shared extremely significant posi-tive correlation with grain length and length-width ratio, but no significant correlation with grain width and thickness. The QTL analysis of grain weight was carried out using one-way analysis of variance and Dunnett＇s test. Nineteen stable QTLs re-sponsible for grain weight were identified over two years. Al 19 QTLs were identi-fied on al chromosomes except for chromosome 10 and 12 at a significance level of P≤0.001. Among them, 10 QTLs had a positive effect and were derived from the Nipponbare al ele, the additive effect of these QTLs ranged from 0.49 to 2.74 g, and the contributions of the additive effects ranged from 2.00% to 11.05%. Another 9 QTLs had a negative effect and were al derived from Guangluai 4 al ele, the ad-ditive effect of these QTLs ranged from 0.60 to 2.35 g, and the contributions of the additive effects ranged from 2.40% to 9.84%. The results provide a basis for the fine mapping and gene cloning of novel locus associated with rice grain weight.

孕穗期高温对水稻颖壳发育的影响

[目的]揭示孕穗期高温是影响颖壳发育的关键时期,为北方水稻生产中预防高温热害提供理论依据。[方法]以千重浪2号为试验材料,在盆栽条件下研究孕穗期高温胁迫对颖壳发育的影响及颖壳大小与粒重的关系。[结果]孕穗期高温显著地降低了颖壳的长度、宽度和面积。强、中势粒降低幅度最大的处理时期是叶龄余数为1.0;而弱势粒降低幅度最大的时期是叶龄余数为0即剑叶完全展开时。相关分析表明,颖壳大小与粒重的关系更为密切,随着颖壳长、宽和面积的增加,粒重也明显增加。[结论]在水稻生产上,在孕穗期要特别注意预防叶龄余数接近1.0时的热害,根据天气状况,采取相应的预防措施。

多因素的筛选和权重估计的1000 m跑预测模型

为了提高运动成绩的预测模型精度,为运动员合理训练提供科学基础,提出基于多因素筛选与权重估计的1 000 m跑成绩预测模型。先构建1 000 m跑成绩统计参数分析模型,获取1 000 m跑成绩预测时的全部影响因素;然后使用基于多因素筛选的1 000 m跑成绩核心预测因素提取方法,在全部影响因素中提取1 000 m跑成绩核心预测因素;最后通过核心预测因素的加权形式完成预测模型的构建。将所构建模型应用于仿真测试中可知,该模型的预测结果和对比模型相比,预测结果和真实成绩吻合度最高,且预测时间最短,可在最少的时间中实现最高精度的1 000 m跑成绩预测。

QTL mapping of grain appearance quality traits and grain weight using a recombinant inbred population in rice(Oryza sativa L.)

supported by a grant from the National High-Tech R＆D Program of China （2014AA10A603, 2014AA10A604）;a grant from the Youth Foundation in Sichuan, China （2011JTD0022）;the special fund for China Agricultural Research System （CARS-01-08）;the Provincial Specialized Funds for Innovation Ability Promotion in Sichuan, China （2013GXJS005）

Effects of Powdery Mildew on 1 000-Kernel Weight, Crude Protein Content and Yield of Winter Wheat in Three Consecutive Growing Seasons

In order to clarify the impact posed by wheat powdery mildew （Blumeria graminis f. sp. tritici） on the yield and yield components in different epidemic seasons, field trials were conducted in three growing seasons, 2009-2010, 2010-2011 and 2011-2012, in Langfang City, Hebei Province, China. The relationships between 1000-kernel weight, crude protein content of grain and yield and disease index （DI）, as well as area under disease progress curve （AUDPC） were studied. The models of the percentage of loss of 1000-kernel weight, crude protein content and yield were constructed using DI at critical point （CP） of growth stages （GS） and AUDPC in the three growing seasons, respectively. The CPs for estimating 1 000-kernel weight, crude protein content of grain and yield of wheat caused by powdery mildew were GS 11.1, GS 10.5.3 and GS l 0.5.3, respectively. Models based on DI at CP to estimate the percentage of loss of 1000-kernel weight, crude protein content of grain and yield were better than models based on AUDPC. And models of the percentage of loss of 1000-kernel weight, crude protein content and yield for 2011-2012 season were significant different from these for 2009-2010 and 2010-2011 seasons. These results indicated that besides powdery mildew, weather conditions also had influence on 1 000-kernel weight, crude protein content of grain and yield loss of wheat when powdery mildew occurred.

丙酰芸苔素内酯施用浓度对水稻植株性状和产量的影响

为了明确丙酰芸苔素内酯对水稻植株性状和产量的作用,采用单因素拉丁方设计,试验因素为0.003%丙酰芸苔素内酯水剂施用浓度,设4个处理,处理A稀释500倍液,处理B稀释2 000倍液,处理C稀释3 000倍液,处理D稀释4 000倍液,设喷施等量清水空白对照(CK),每个处理5次重复。收获前调查记录植株相关性状和产量构成因子,每个重复单独收获脱粒烘干测产。结果表明,水稻移栽后,丙酰芸苔素内酯稀释2 000倍液叶面喷施2次,植株高度为100.9 cm,分蘖数为23.0,穗下节间、倒2节间和倒3节间的长度分别为22.3、19.7和16.4 cm,每穗总粒数、实粒数和千粒重分别为137.2粒、128.9粒和32.1 g,产量为7 362.7 kg/hm~2。因此,0.003%丙酰芸苔素内酯水剂稀释2 000倍液可增加水稻植株高度、节间长度、分蘖数和提高产量。

0.003%丙酰芸苔素内酯对水稻生长、 产量和品质影响

为了明确丙酰芸苔素内酯对水稻生长、产量和品质的作用,秧苗期采用单因素完全随机设计,试验因素为0.003%丙酰芸苔素内酯水剂施用次数,设2个处理,处理A:喷施1次,处理B:喷施2次,设喷施清水空白对照(CK)。大田期采用单因素随机区组设计,试验因素为丙酰芸苔素内酯稀释倍数,设稀释1000倍液,2000倍液,3000倍液和4000倍液4个处理和一个喷施清水空白对照(CK)。秧苗期调查记录地上鲜重、地下鲜重,株高、根长和总根数,大田期调查记录水稻株高、有效穗数、每穗总粒数、结实率、千粒重和产量,并测定淀粉含量。结果表明,水稻秧苗期用0.003%丙酰芸苔素内酯水剂常规用量稀释2000倍液喷施1次,可显著提高秧苗素质,地上鲜重3.4 g,地下鲜重1.7 g,株高36.7 cm,根长16.3 cm,总根数50.7条;0.003%丙酰芸苔素内酯水剂常规用量稀释2000倍液或3000倍液在水稻移栽后5和12 d各喷施1次,对水稻提质增产效果明显。因此,0.003%丙酰芸苔素内酯水剂合理控制使用浓度和适期可以促进水稻生长发育。

Relationship of Milk Line Position with Grain Weight and Mechanized Harvest of Summer Corn

To investigate the relationship of milk line position with grain weight and mechanized harvest of summer corn in Huang-Huai-Hai Region, 8 varieties （A, B, C, D, E, F, G, H） with large planting areas were selected to measure the grain filling rate, 100-grain weight, water content and milk line position, and the correlation was analyzed. Results showed that when the milk line position was 90%, the grain filling of all the 8 varieties finished and 100-grain weight reached the highest value, which was 43.02 g. The grain filling time was in positive correlation with 100-grain weight. However, when the milk line position completely disappeared, the 100-grain weight was reduced by 8.66% at most. There was no significant difference during the periods of grain weight rising, but in the periods of grain weight falling, the traits of D, E, H were significantly different with the other varieties, and water loss rate of C and A showed significant difference with the other six varieties. The water content of grain was negatively correlated with milk line position. When the milk line percentage was 90% , the grain water content was less than 30% . The key factor influencing the mechanized harvest of summer corn is harvesting time, rather than the varieties. Moreover, milk-line position of 90% is the best time for harvest; if the harvest is too late, the yield will be reduced with varying degrees.

小麦转录因子TaMYB5-3B与株高和千粒重相关

MYB转录因子在植物生长发育过程中发挥着重要作用。本研究克隆了小麦3B染色体上的TaMYB5-3B基因,基因组序列全长3005bp,其中编码区上游为2112bp,编码区为893bp,包含2个外显子和1个内含子,编码一个R2R3-MYB蛋白。序列多态性分析表明,在TaMYB5-3B的–2048、–1632、–1178、–1156、–504、–461、–433和61 bp处各有1个SNP位点,分别是G/A转换、G/A转换、G/A转换、T/C转换、C/T转换、A缺失、T缺失和T/A颠换,这8个SNP位点连锁。基于启动子区SNP-1632的变异开发分子标记,检测小麦自然群体的基因型,与表型性状进行关联分析,结果显示TaMYB5-3B与株高、穗下节长和千粒重显著相关。TaMYB5-3B在群体中有2种单倍型Hap-3B-1和Hap-3B-2,其中Hap-3B-2是植株较矮、千粒重较高的优异单倍型。在我国的小麦育种历程中Hap-3B-2受到了正向选择,在育成品种中的频率逐步增加,但仍然有进一步的应用潜力。研究结果为深入探讨小麦株高和产量的形成机制提供参考,也为小麦株型和产量分子育种提供了基因资源与选择标记。

施氮对稻茬弱筋小麦生长特性、品质与产量的影响

为探索安徽省沿淮稻茬弱筋小麦提升产量、品质的适宜施氮量,在大田试验的条件下,设置0、75、150、225和300 kg·hm^(-2)共5个施氮水平,研究施氮对安徽省沿淮稻茬麦区弱筋小麦产量、品质、干物质积累与转运,以及氮素利用效率的影响。结果表明,在0~300 kg·hm^(-2),随着施氮量的增加,小麦分蘖数、株高、叶面积指数(LAI)和叶绿素相对含量(SPAD)均呈上升趋势,花后21 d小麦冠层光谱反射率在760~925 nm逐渐上升,在925~1300 nm先升后降。在孕穗至成熟期,小麦干物质积累量和花前营养器官干物质转运量随着施氮量的增加呈先升后降趋势,花前营养器官干物质转运对籽粒的贡献率不断下降,而花后干物质生产量和其对籽粒的贡献率均逐渐升高。增加施氮量能提高小麦穗粒数和有效穗数,而小麦千粒重和籽粒产量均呈先升后降趋势,小麦籽粒产量均在225 kg·hm^(-2)施氮量处理下达到最大值,与不施氮处理相比,施氮量为75~300 kg·hm^(-2)时,试验点1和试验点2的小麦籽粒产量分别增加了127.58%~230.45%和72.21%~131.94%。施氮量的增加使氮肥表观利用率、氮肥农学利用率、氮肥偏生产力逐渐下降。在225 kg·hm^(-2)施氮量下小麦籽粒品质指标较优,施氮量为300 kg·hm^(-2)时小麦籽粒蛋白质含量超过国家弱筋小麦蛋白质含量标准;与不施氮处理相比,施氮量为75~300 kg·hm^(-2)时,两试验点小麦籽粒蛋白质含量分别增加12.02%~44.21%和9.64%~34.30%。总体上,当施氮量为225 kg·hm^(-2)时小麦籽粒品质指标较优,且产量最高。综合高产、优质的选择条件,225 kg·hm^(-2)是安徽省沿淮稻茬弱筋麦区适宜的施氮量。

西南糯红高粱抗炭疽病资源筛选及病情危害研究

明确西南高粱炭疽病病级与为害程度的关系,筛选出高粱抗炭疽病种质资源,为抗炭疽病育种奠定材料基础。通过人工培养炭疽病菌强致病力菌株ZG-FS-1进行大田喷雾接种,按病害分级标准进行分级以确定抗性等级。再与未接种组进行比对分析,得出粒重损失率以及发芽损失率。92份高粱资源中,有高抗(HR)资源10份,抗病(R)资源10份,中抗(MR)资源5份,感病(S)资源20份,高感(HS)资源47份。高抗(HR)资源、抗病(R)资源、中抗(MR)资源、感病(S)资源、高感(HS)资源穗粒重平均损失率分别为4.37%、6.69%、8.89%、34.12%和52.50%,千粒重平均损失率分别为1.81%、2.98%、5.59%、14.56%和28.89%,发芽率平均损失率分别为0.97%、5.40%、5.76%、11.11%和20.46%。高粱炭疽病不仅导致高粱大幅减产,还导致高粱种子发芽率降低。高粱炭疽病抗性可通过人工接种准确鉴定,筛选出的抗性资源可作为抗性遗传改良的育种材料。

基于气象要素的冬小麦分期播种研究

利用山东省泰安农业气象试验站2019—2020年与2020—2021年气象观测资料,以小麦品种泰科麦31为试验材料,分析不同播期气象条件对冬小麦生长及产量的影响。结果表明:日照时数在冬小麦出苗至开花阶段起重要作用,发育期天数与日照时数成极显著相关,日照越充足苗情越好;越冬过程的开始主要受日最高气温及其持续时间的影响,越冬期持续时间的长短则受日最低气温及其持续时间的影响;各播期处理冬小麦灌浆过程均符合Logistic生长规律,不同播期冬小麦灌浆速率与各气象要素之间的关系不同;冬小麦千粒重受前期生长状况与越冬期积温、负积温的影响,与日照时数成正相关关系;冬小麦越冬期低温持续时间短有利于其产量的提高。

Gn1a基因靶向敲除对粳稻产量构成因素的影响

【目的】我国多数人口以稻米为主食,稻米产量关系国家粮食安全,提高单产仍然是目前水稻育种最重要的目标。水稻中OsGn1a/OsCKX2基因失活被报道可提高穗粒数从而提高产量。拟通过CRISPR/Cas9技术在粳稻品种“晚粳34”中对该基因进行靶向敲除,从而快速提高其产量。【方法】通过基因编辑技术对OsGn1a基因进行定点突变,在成功获得OsGn1a基因功能缺失突变体后,利用获得的同时包含野生型和突变型的3个独立突变株系衍生的不含转基因成分的纯合突变株(突变组)和非突变株(野生型对照组)姊妹系(T3代)进行试验,同株系突变组和对照组不同重复(3个重复)田间排布采用完全随机设计,不同株系独立排布,通过比较3个株系各自突变组和对照组间产量构成因素之间的差异,探究Gn1a基因功能缺失对“晚粳34”产量构成因素的影响。【结果】3个株系(编号分别为#01、#06和#16)突变组与对照组相比,每穗粒数均显著增加,增幅分别为26.2%、19.8%和19.0%,均值21.67%;对于千粒质量,其中两个株系(#06和#16)突变组也显著增加,增幅分别为8.0%和8.8%,而另一个株系则无显著差异;而对于有效分蘖数,从均值上看3个株系均不同程度降低,不过只有#06和#16两个株系差异显著,降幅分别为9.8%和15.7%,另外一个株系降幅虽然高达13.4%,但统计上差异并不显著;对于结实率,3个株系均无显著差异。依据产量构成因素数据计算单株理论产量,突变组与对照组相比,3个株系的单株理论产量变化并不一致,从均值上看,2个突变体株系(编号分别为#01和#06)增产(增幅35.1%和18.5%),但统计上差异并不显著,另外1个突变体株系(编号为#16)减产(减幅27.3%),统计上差异显著。【结论】在粳稻中敲除OsGn1a基因可有效提高穗粒数,但可能伴随千粒质量和有效分蘖数的变化,在某些环境下可使千粒质量增加同时导致分蘖数减少,最终单株产量也发生变化,不同条件下可能获得不同结果,提示育种中仅仅通过应用Gn1a无功能等位基因并不一定能提高水稻产量。

科尔沁沙地最典型地区春小麦千粒重与气象因子的相关性

为了研究科尔沁沙地最典型地区气象条件对春小麦千粒重的影响规律及特征。以奈曼旗国家气象站近28年春小麦观测数据及地面气象观测数据为研究对象,进行相关分析和回归分析。结果表明:春小麦生长后期日照时数与千粒重负相关,抽穗-成熟期相关系数为-0.485,乳熟-成熟期相关系数为-0.444;开花-乳熟期气温日较差与千粒重呈显著性正相关,相关系数为0.392;孕穗-抽穗期需要较低的空气相对湿度,相关系数为-0.540,开花期春小麦根部需要较高的土壤相对湿度,相关系数为0.527。建立了春小麦千粒重预报回归模型,经检验拟合度较高,可为今后春小麦种植管理及产量预报提供依据。