冬小麦持绿和灌浆特征及其抗早衰特性评价

选择23个小麦品种(系),在大田条件下测定了小麦花后旗叶叶绿素含量、颖壳叶绿素含量、籽粒重量、籽粒饱满度等与早衰有关的形态和生理指标,并分别对其花后旗叶叶绿素含量、花后旗叶与颖壳的叶绿素含量比值、粒重比和饱满度以及综合4项指标进行聚类分析,以建立科学的早衰鉴定指标。结果显示:(1)23份小麦材料以花后旗叶叶绿素含量变化可分为4个类型:下降迟且幅度小型、下降早而幅度较大型、下降早且幅度小型、下降早且幅度大型,除第2类型外,其花后旗叶叶绿素含量下降幅度依次增大。(2)以花后旗叶和颖壳叶绿素含量比值变化将其分为3种类型:穗黄叶绿型、同步转黄型、穗绿叶黄型,其比值依次减小。(3)以粒重比可分为3种类型:灌浆充实型、灌浆相对不充实型、灌浆不充实型,其比值依次减小。(4)以饱满度可分为4个类型:饱满型、相对饱满型、相对瘪瘦型和瘪瘦型,其饱满度依次减小。(5)综合以上4项指标可分为4种类型:穗黄叶绿型、正常落黄成熟型、轻度早衰型和典型早衰型;而以饱满度为鉴定指标最接近综合鉴定分析结果。研究发现,籽粒饱满度(干籽粒体积与其充分吸涨后的体积的比值)可作为鉴定小麦早衰的简单、快捷指标,旗叶和颖壳叶绿素含量比较分析可作为田间的初步鉴定指标。     

气象因子对寒地玉米籽粒灌浆进程的影响

为探讨粒重和籽粒灌浆参数与气象因子之间的关系,选择早熟品种"德美亚1号"、中熟品种"吉单27"和晚熟品种"郑单958"3个品种,于2017—2018年在哈尔滨进行播期试验,对籽粒发育动态及灌浆特性进行了分析。结果表明:产量与粒重呈极显著正相关,与穗粒数相关不显著;粒重与灌浆速率呈显著正相关,与达到最大速率的时间和灌浆活跃期无显著相关性;积温、辐射、饱和水气压差与灌浆速率呈极显著正相关;前期温度升高,辐射增大有利于早熟品种灌浆速率的提高,而后期温度降低、辐射减少显著缩短晚熟品种灌浆时间,降低其灌浆速率;粒重与花后的降水量呈负相关,与辐射量呈正相关,与积温的关系因品种而不同;积温是影响粒重最主要的气象因子,当早、中、晚熟品种在灌浆期积温分别达到920、1020、1100℃时,可获得最大粒重。     

基于主成分分析的优质鸡肉质评价研究

优质鸡的内涵在于肉质,但目前肉质的评定还没有一个统一的标准．本研究通过对大恒优质肉鸡5个新品系共150个个体和与肉质有密切联系的8个理化指标进行主成分分析,8个原始指标被综合成了3个独立的新指标：主成分1,肉质因子;主成分2,口感和风味因子;主成分3,嫩度因子,筛选出的3个新指标包含了原有指标的大部分信息,累积贡献率达到88．42％．通过比较3个指标的综合得分大小对10个群体的优质鸡肉质进行了评价,结果表明：S01系肉质最好,S03系次之,而D99系肉质最差,而且母鸡肉质均优于公鸡．同时利用第一主成分制定了优质鸡的肉质指数．     

不同小麦品种(系)耐湿性的综合评价

把小麦各性状的耐湿系数作为衡量各单项耐湿能力大小的指标,用主成分分析将各单项耐湿系数综合成几个新的相互独立的综合指标,再利用隶属函数求出综合指标的隶属值。这样,通过各小麦品种（系）的隶属值可求出各品种（系）耐湿性度量值后,可以较准确地评价各小麦品种（系）的耐湿性。     

花后干旱和渍水对不同品质类型小麦籽粒品质形成的影响

 防雨池栽条件下研究了花后干旱和渍水胁迫对两个不同品质类型小麦（Triticum aestivum）品种籽粒产量和品质形成的影响。结果表明,花后渍水和干旱处理明显降低了小麦籽粒产量和蛋白质产量。在整个灌浆期内干旱处理明显提高了籽粒蛋白质和醇溶蛋白含量,而渍水处理降低了籽粒蛋白质及其组分的积累量。籽粒总淀粉和直链淀粉含量以渍水处理最高,而支链淀粉以对照最高。干旱处理提高了籽粒干、湿面筋含量、沉降值和降落值,而渍水处理降低了上述品质指标。试验表明干旱和渍水胁迫对小麦籽粒蛋白质与淀粉的含量和组分及面粉品质等均有不同程度的影响,从而改变了不同品质类型小麦的籽粒品质。     

小麦农艺性状与品质特性的多元分析与评价

估算96个小麦品种(系)的11个农艺性状和10个品质特性参数的主成分,并以主成分和欧氏距离为基础,分别作二维排序分析和聚类分析。农艺性状的前4个主成分反映了85.3450%的原始数据信息量;品质特性的前4个主成分代表了89.1483%的原始数据信息量。以96个材料的主成分得分绘制二维排序图,27个小麦品种(系)表现为矮秆、子粒和旗叶较大,丰产性较好、综合农艺性状优良;32个小麦品种(系)表现为铁、锌含量较高,加工品质较好、综合品质特性优良。在系统聚类图中,农艺性状和品质特性分别被聚成5类。综合农艺性状较好的材料主要集中在第Ⅲ类和第Ⅳ类;综合品质特性较好的材料主要集中在第Ⅰ类和第Ⅱ类。综合分析发现,同时兼顾丰产性较好且子粒铁、锌含量较高,品质特性较好的小麦品种(系)有:泰山9818、西农822、轮选719、杨-31、西安837和中育9383。将聚类分析和二维排序分析结合起来,能较好的对小麦的性状组成做出综合评价,鉴定和评价出优质、高产、综合性状优良的小麦品种(系),为小麦遗传育种提供优良的种质资源,为合理选配亲本提供参考。     

水稻品种灌浆期耐热性的综合评判

建立了一种对水稻品种的灌浆期耐热性进行综合评判的方法.选取籽粒充实度、秕粒率、饱粒密度、垩白米率、垩白度等5个与水稻灌浆期耐热性强弱密切相关的性状,以参评品种这5个性状的耐热系数为指标,应用主成分分析法将5个彼此相关的单项指标转化为2个累计贡献率达到85%以上的相互独立的综合指标,根据每一品种的5个单项性状的耐热系数和综合指标的标准化特征向量求出每一品种2个综合指标的得分.计算每一品种2个综合指标得分的隶属函数值,并以综合指标的贡献率来确定2个综合指标的权重,在此基础上进行加权求和,从而得到每一品种灌浆期耐热性的综合评判值（D值）.采用系统聚类分析方法对各品种的综合评判值（D值）进行数量分类,同时结合生产实际的要求,可把每一品种划归为不同的耐性等级.外部独立样本组的统计检验以及实践验证的结果表明,所建立的综合评判方法具有理想的效果,可以对不同品种灌浆期综合耐热性能的强弱作出客观、准确的评判.     

小麦不同品种光合速率和14 C同化物分配对源库比改变的影响

 选用千粒重大小不同的小麦品种,研究了去除顶端两个小穗对两类品种(大粒品种和小粒品种)穗部性状、籽粒平均灌浆速率、单穗平均增重速率、植株光合速率及14C同化物运输分配的影响。试验结果表明,去除顶端两个小穗后,两类品种的籽粒平均灌浆速率和单穗平均增重速率(分别表征籽粒库容活性和穗粒库容活性)相应提高,穗粒重表现为补偿性增长。两类品种比较,小粒品种的增长幅度大于大粒品种。穗粒库容活性增强使得小粒品种灌浆中后期的植株光合速率提高,使两类品种分配到籽粒中的14C同化物比例增加。从而表明,无论是植株光合速率还是同化物的运转分配皆受库容活性的调控,调控方式和幅度因品种类型而不同。     

小麦品种品质性状的基因型因子分析

用陕西省关中小麦品种区域试验所选用的20个小麦品种(品系)在12个试点1996／97、1997／98两年度的数据资料,通过基因型因子分析,探讨小麦品种籽粒品质性状间相互关系的内在规律。结果表明：可将12个品质指标用4个“公共因子”表示。因子1对蛋白质含量、沉淀值、形成时间、稳定时间、软化度与评价值等品质性状起支配作用,主要反映的是蛋白质的质与量;因子2对湿面筋含量、容重和出粉率起支配作用,反映了湿面筋含量与磨粉品质之间存在着较密切的、直接的联系;因子3对籽粒硬度与吸水率起支配作用,反映了小麦籽粒的质地结构特性;因子4中,只有千粒重有较大载荷。表明千粒重与其它品质性状的直接联系较小,受相对较为独立的遗传因素控制。     

灌浆期不同阶段遮光对小麦籽粒蛋白质组分含量和加工品质的影响

选用强筋小麦济麦20、中筋小麦泰山23和弱筋小麦宁麦9号3个小麦品种,设置了灌浆期不同阶段遮光处理:开花后不遮光(S0)、0～11 d遮光(S1)、12 ～23 d遮光(S2)、24～35 d遮光(S3),研究了其对不同小麦品种籽粒蛋白质组分含量和加工品质的影响.结果表明:3个小麦品种的籽粒清蛋白+球蛋白含量遮光处理间无显著差异;遮光均显著提高了济麦20和泰山23的高分子量谷蛋白亚基、低分子量谷蛋白亚基、谷蛋白、醇溶蛋白和总蛋白含量,其中灌浆中期遮光(S2)处理提高幅度高于其他处理;灌浆中期(S2)和后期(S3)遮光处理显著提高了宁麦9号各蛋白质组分含量.遮光显著降低了小麦籽粒产量,提高了籽粒面团形成时间、面团稳定时间和沉降值,其中灌浆中期遮光处理更为显著,表明籽粒品质的形成与灌浆中期的光照条件更为密切.总体上灌浆期遮光对3个小麦品种籽粒产量、蛋白质组分含量及加工品质指标的调节幅度为济麦20＞泰山23＞宁麦9号.     

Studies on the nature of relationships between grain size,spikelet number,grain yield and spikelet filling in late duration varieties of rice (Oryza sativa L.)

Summary Studies on the nature of relationship between grain size (in terms of thousand grain weight), grain number, rate of filling and yield have been worked out with late duration (140–150 days) rice varieties. Grain number per m², grains per panicle and yield showed a negative relationship with grain size. There was no compensatory balance between grain size and grain number within a range of thousand grain weight of 15 to 30 g. Based on the peaks in grain filling activity, the varieties were classified into four groups. There was no relationship between grain size and rate of grain filling thereby suggesting that grain filling is determined by inherent endogenous factors.     

The parameters of grain filling and yield components in common wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.) and durum wheat (<Emphasis Type="Italic">Triticum turgidum</Emphasis> L. var. <Emphasis Type="Italic">durum</Emphasis>)

Final grain dry weight, a component of yield in wheat, is dependent on the duration and the rate of grain filling. The purpose of the study was to compare the grain filling patterns between common wheat, (Triticum aestivum L.), and durum wheat, (Triticum turgidum L. var. durum), and investigate relationships among grain filling parameters, yield components and the yield itself. The most important variables in differentiating among grain filling curves were final grain dry weight (W) for common wheat genotypes and grain filling rate (R) for durum wheat genotypes; however, in all cases the sets of variables important in differentiating among grain filling curves were extended to either two or all three parameters. Furthermore, in one out of three environmental conditions and for both groups of genotypes, the most important parameter in the set was grain filling duration (T). It indicates significant impact of environmental conditions on dry matter accumulation and the mutual effect of grain filling duration and its rate on the final grain dry weight. The medium early anthesis date could be associated with further grain weight and yield improvements in wheat. Grain filling of earlier genotypes occurs in more temperate environments, which provides enough time for gradual grain fill and avoids the extremes of temperature and the stress of dry conditions.     

Genetic analysis of grain protein-content,grain yield and thousand-kernel weight in bread wheat

Grain yield and grain protein content are two very important traits in bread wheat. They are controlled by genetic factors, but environmental conditions considerably affect their expression. The aim of this study was to determine the genetic basis of these two traits by analysis of a segregating population of 194 F(7) recombinant inbred lines derived from a cross between two wheat varieties, grown at six locations in France in 1999. A genetic map of 254 loci was constructed, covering about 75% of the bread wheat genome. QTLs were detected for grain protein-content (GPC), yield and thousand-kernel weight (TKW). 'Stable' QTLs (i.e. detected in at least four of the six locations) were identified for grain protein-content on chromosomes 2A, 3A, 4D and 7D, each explaining about 10% of the phenotypic variation of GPC. For yield, only one important QTL was found on chromosome 7D, explaining up to 15.7% of the phenotypic variation. For TKW, three QTLs were detected on chromosomes 2B, 5B and 7A for all environments. No negative relationships between QTLs for yield and GPC were observed. Factorial Regression on GxE interaction allowed determination of some genetic regions involved in the differential reaction of genotypes to specific climatic factors, such as mean temperature and the number of days with a maximum temperature above 25 degrees C during grain filling.     

胡麻资源萌发期耐盐综合性评价

筛选胡麻耐盐品种,对胡麻产业可持续发展应对盐渍胁迫具有重要现实意义。试验选用100 mmol·L^-1的NaCl溶液对28份胡麻资源种子进行胁迫,并测定发芽率、总鲜重、下胚轴鲜重、下胚轴干重、下胚轴长、胚根鲜重、胚根干重和胚根长等相关指标,通过相关性分析、因子和主成分分析、聚类分析和逐步回归分析对11个指标进行综合分析,对28份胡麻资源萌发期耐盐性做出评价,并筛选出胡麻萌发期耐盐性鉴定的关键指标。结果表明：经相关分析,11个指标中多项指标间都是极显著或显著的正相关;因子和主成分分析将11个单项指标转化成3个综合指标,第Ⅰ主成分为下胚轴长势情况,第Ⅱ主成分为胚根长势情况,第Ⅲ主成分为种子萌发情况;聚类分析将28份胡麻资源划分为4大类：耐盐型、中等耐盐型、盐敏感型和强盐敏感型。雁杂10号、轮选1号为强耐盐材料;陇亚4号、R40号、DYMS为较强耐盐材料;逐步回归分析建立了胡麻萌发期耐盐能力预测的数学评价模型,筛选出总鲜重、胚根干重、发芽指数和下胚轴长这4个鉴定指标是胡麻萌发期耐盐能力鉴定的关键指标。以这4个筛选指标计算出的预测值与综合评价计算出的综合Z值之间极显著相关（R²=0.991 8^**）,表明鉴定结果具有较高的准确性,可以代替原来11个指标对胡麻萌发期耐盐性进行评价。     

Variation in responses to boron in rice

Background and aims

Boron (B) deficiency depresses grain set and grain yield of wheat and maize while having little effect on their vegetative growth. This paper describes effects of B deficiency in rice and how these vary with planting season and variety.

Methods

Three rice varieties (KDML105, CNT1, SPR1) were grown in sand culture without (B0) and with 10 μM (B10) B added to the nutrient solution, in the cool season of 2007/08 and 2008/09 and the hot season of 2011 in Chiang Mai, Thailand (18°47′N, 98°59′E). Boron responses were measured in growth and yield parameters, pollen viability and B concentration of the flag leaf and anthers at anthesis.

Results

Grain weight was strongly depressed by B deficiency ranging from 28 % in SPR1 to 79 % in CNT1, and the yield was much lower in the cool season than in the hot season plantings. The variation in grain weight was closely associated with grain set and number of spikelets but not with shoot dry weight or tillering. Grain set was closely related to pollen viability, and both were increased with increasing anther B concentration at >20 mg B kg^?1. In addition to its adverse effect on grain set, B deficiency also depressed grain filling and weight of individual grains in rice.

Conclusions

Boron deficiency depressed rice grain yield through adverse effects on reproductive growth, panicle and spikelet formation and grain filling, in addition to grain set as in wheat and maize.     

Understanding the regulation of cereal grain filling: The way forward

During grain filling, starch and other nutrients accumulate in the endosperm; this directly determines grain yield and grain quality in crops such as rice (Oryza sativa), maize (Zea mays), and wheat (Triticum aestivum). Grain filling is a complex trait affected by both intrinsic and environmental factors, making it difficult to explore the underlying genetics, molecular regulation, and the application of these genes for breeding. With the development of powerful genetic and molecular techniques, much has been learned about the genes and molecular networks related to grain filling over the past decades. In this review, we highlight the key factors affecting grain filling, including both biological and abiotic factors. We then summarize the key genes controlling grain filling and their roles in this event, including regulators of sugar translocation and starch biosynthesis, phytohormone-related regulators, and other factors. Finally, we discuss how the current knowledge of valuable grain filling genes could be integrated with strategies for breeding cereal varieties with improved grain yield and quality.     

陕北谷子品种更替过程中产量及农艺性状的演变

选择不同年代(1960s—1970s、1980s—1990s、2000s—2010s)在陕北种植的6个谷子品种为试验材料,于2018—2019年在陕西榆林进行田间试验,研究分析了不同年代品种谷子产量及其农艺性状的演变特征。结果表明: 随年代更替,谷子品种产量呈现明显增加趋势,2000s—2010s选育的品种平均产量分别为0.46(2018)和0.66 kg·m^-2(2019),较2000s前的品种显著增产,增产幅度22%～53%;株高、穗重、叶重和杆重与产量趋势类似;而千粒重和穗长表现相对稳定,随品种更替并未呈现明显变化;旗叶宽度虽然变幅不大,但随品种更替呈明显增大趋势。相关性分析表明,穗重、杆重、叶重和株高与产量之间呈极显著相关。主成分分析显示,2000s—2010s谷子品种具有更大的优势。陕北谷子品种更替过程中主要通过株高和穗重的改良来增加单位面积产量,未来谷子高产育种应注重株高、穗重、杆重和叶重性状改良,尤其应探索适合机械收割的最优株高。     

The Influence of Source of Photosynthate and Sink Size on Grain Yield in Oats (Avena sativa L.)

Experiments were conducted using leaf defoliation and floretemasculation techniques to study sourcesink relationships inthe spring oat cultivars Clintland 60 and Garry. Grain yielddecreased more with leaf lamina removal at panicle emergencethan at anthesis. Removing the penultimate leaf reduced yieldat least as much as removing the flag leaf, indicating the relativeimportance of the penultimate leaf in oats. Removing the flagand penultimate leaves together at panicle emergence, or allleaves, lowered grain yield by 40 per cent, primarily due tothe development of fewer grains. Similar defoliation at anthesisreduced yield by 20 per cent, due mainly to lower single grainweights. While there was some evidence of compensation effectsin Clintland 60, lower leaves were unable to compensate forremoval of flag and penultimate leaves. Grain filling dependedupon an adequate photosynthetic area in the upper portions ofthe plant. Increases in individual grain weights were obtained when grainnumber per panicle was reduced 40 per cent or more by emasculation.Increases in single grain weights did not compensate for lossin numbers. The potential capacity of the grains to accumulateassimilates was not fully exploited under normal field conditions.Straw weight did not increase and total plant dry weight decreasedwith lower grain numbers, indicating a lower than normal rateof production of assimilates.     

9个小麦品种(系)比较试验中的主要农艺性状

目的:通过对9个小麦品种(系)的比较试验中的主要农艺性状统计分析,筛选出比较适宜现阶段在贵阳地区乃至贵州省栽培的高产优质小麦品种(系)。方法:9个小麦品种(系)在试验地里随机区组排列,3次重复,记录小麦的全生育期,出苗数,田间生育期,株高,有效分蘖数,每株干重,穗长,穗粒重等,并在Excell上进行统计分析。结果:全生育期在200天左右,出苗数有3个超过100万/ha,最低只有44．8万/ha,株高在50 cm以上的有6个品种(系),3个在40 cm-50 cm之间,有效分蘖数400万/ha以上的有3个,最低的是199．1万/ha,每株干重最高是8．5 g,最低是5．7 g,穗长整齐度除98-22外都优于对照,经LSR法测验表明,贵农15,黔98353,黔麦15分别与夏繁29,98-28,贵单5号,黔98284-82,黔0110都达到差异显著水平,贵农15,黔98353,黔麦15分别与98-22达到差异极显著水平,其余的差异皆不明显。结论:可以初步得出贵农15,黔98353,黔麦15目前可以作为在贵阳地区推广种植的较优品种(系)。