甘蔗产量构成因素与产量的关系

对32个甘蔗品种或组合的产量构成因素与产量的相关、回归、通径关系和鲜蔗产量估测差异进行分析，结果表明：茎高与有效茎呈极显著正相关；茎高、有效茎与鲜蔗产量呈极显著正相关；除茎径外，其余二性状与产量的偏相关系数为极显著正相关，偏回归系数达极显著水平。茎径、茎高、有效茎对产量的直接通径效应除茎径外，其余均为较高正值，但以茎高最高，有效茎次之。因此，若想得到产量较高的甘蔗品种，固定其余因素，选择植株高大的对提高鲜蔗产量效果较佳；以有效茎为选择指标时，可在茎较高选择鲜蔗产量较高的材料。以茎高、茎径和有效茎计算理论值来估测鲜蔗产量的经验公式（Y＝1896．3107＋0．690DX1^2X2X3),理论上是可行的。     

不同蔗区甘蔗品种（系）分蘖性状比较及其对产量和产量构成因子的影响

为明确不同蔗区甘蔗品种（系）间的分蘖性状差异及其对产量及产量构成因子的影响,在3个蔗区的5个试验点对4个不同甘蔗品种（系）的分蘖农艺性状、产量构成因子进行显著性、相关性、变异系数和通径分析。结果表明,不同蔗区甘蔗品种（系）间的分蘖性状差异显著,分蘖率和分蘖苗数对有效茎的产生具有重要作用;根据分蘖农艺性状的差异将甘蔗分为低分蘖甘蔗品种（系）（新台糖22号、桂糖42号）和高分蘖甘蔗品种（系）（桂热2号、凉蔗03-81）,与高分蘖甘蔗品种（系）产量相关性最高的产量构成因子是有效茎数（0.76^**）,低分蘖甘蔗品种（系）则是单茎重（0.83^**）,高分蘖（0.64^*）和低分蘖品种（系）的分蘖率（0.68^*）与有效茎数呈显著正相关关系;有效茎数对2种类型甘蔗产量的直接通径系数最大,是影响甘蔗产量的主要因子;分蘖苗数和分蘖率的变异系数最大,具有较高的改良潜力。综上所述,分蘖可以显著提高有效茎数,从而影响甘蔗产量,且影响甘蔗产量和产量构成因子之间的关系。     

福建沿海雨养型旱坡地新植甘蔗产量结构分析

分析了沿海雨养型旱坡地新植甘蔗的产量结构，结果表明：在构成蔗茎产量的四个因素中，茎长，有效茎数，单茎重与产量之间有显著或极显著的正相关，而茎径与蔗茎产量之间的相关未达到显著水平。在产量相对较低的情况下，有效茎数与蔗茎产量的关系的密切程度较高。通径分析结果表明：单茎重与有效茎数对蔗茎产量的直接效应，中下产量水平时以有效茎数为大，中上产量水平时以单茎数对茎重为大。在径长，茎径，有效茎数三者对蔗茎产量的     

秋播蚕豆产量构成因子的初步分析

蚕豆产量构成因子包括有效分枝、 有效荚数、 实粒数和百粒重, 四者的相对最佳协调关系是育种家们研究和探讨的热点问题。为筛选适宜安徽省地区种植的高产蚕豆品种, 利用 83份秋播蚕豆材料的小区结果, 采用方差分析法、 相关分析法和灰色关联度分析法对蚕豆产量构成因子进行初步研究分析。结果表明： 有效分枝和实粒数与产量呈极显著正相关, 是影响产量的最重要因素; 有效分枝与有效荚数和实粒数呈极显著正相关。偏相关分析也表明, 产量与有效分枝和实粒数呈极显著正相关, 偏相关系数分别为 0.3152**和 0.4895**。通径分析显示, 实粒数对产量的直接效应最大。关联度分析表明, 对产量贡献由高到低依次为实粒数、 有效分枝、 百粒重、 有效荚数。实际育种中, 在提高蚕豆产量时, 应在优先考虑实粒数增加的基础上, 注意各性状之间的平衡。     

小麦品种淮麦33产量构成因素分析及增产途径探讨

利用2015-2017年江苏省连云港市小麦高产创建万亩示范片33个点次试验资料,对小麦品种淮麦33产量构成因素进行分析。相关分析表明,穗粒数、千粒重与产量呈极显著正相关(r=0.6453**,r=0.7059**),穗数与产量呈微弱正相关(r=0.0712)。籽粒产量与穗数、穗粒数、千粒重的多元回归方程为:Y=-22151.30+15.85X1+270.48X2+261.70X3。通径分析表明,穗粒数对籽粒产量的作用最大(直接通径系数Py=1.0632),其次是穗数(直接通径系数Py=0.7327),千粒重的作用相对较小(直接通径系数Py=0.3303)。淮麦33的高产栽培技术应在适宜群体的基础上,主攻穗粒数,同时兼顾粒重的提高。     

双低油菜主要农艺性状的通径分析

用35个双低油菜品种,进行株高、角果长、分枝高度等主要农艺性状与籽粒产量的遗传相关和通径分析.结果表明,株高、一次有效分枝、单株角果数、每角粒数和千粒重与单株产量呈正相关,其中得与千粒重达极显著正相关(r=0.548 9**);而角果长、分枝高度和二次有效分枝与单株产量呈负相关.株高、单株角果数、每角粒数和千粒重与籽粒产量的直接通径系数均为正值,其中千粒重与籽粒产量的直接通径系数最大(0.679 0),其次是每角粒数(0.396 6)、单株角果数(0.377 3)和株高(0.309 5),而角果长等其它4个农艺性状的直接通径系数均为负值.因此,在油菜高产育种中,应加强对这些主要农艺性状的选择,特别应注重对千粒重、角粒数、单株角果数和株高的选择.     

苦荞主要农艺性状与产量关系的多重分析

以我国不同地区的80份苦荞品种为材料,通过相关分析、通径分析、主成分分析及多元线性回归分析,研究了苦荞主要农艺性状和产量的变异特征及相关关系,确定了构成苦荞产量的主要因子。结果表明,苦荞主要农艺性状和产量的变异系数达7.2%~34.5%,产量与株高、单株粒数、单株粒重呈极显著的正相关,与千粒重呈显著的正相关,与分枝数呈极显著的负相关,而与第一节间长和主茎节数的相关性未达显著水平;苦荞产量的主要决定因子依次为分枝数、单株粒重、株高和千粒重,对产量的决定系数达0.7562。高产型苦荞品种的主要特征为植株高大、单株产量高、千粒重大且分枝较少。     

杂交粳稻产量性状与品质性状相关性分析

为了探明杂交粳稻的产量性状与品质性状间的关系,以5个千粒重介于23.5~27.4 g之间的BT型不育系和40个千粒重介于18.7~31.2 g之间的三系粳稻恢复系,采用5×40 NCⅡ设计方式,配制200个杂交组合为试验材料,对产量性状、品质性状及其相互关系进行了分析,主要结果表明：单株谷重与单株有效穗数、每穗实粒数、结实率、千粒重均呈极显著正相关（r=0.47**,0.63**,0.53**,0.35**）,与穗长呈显著正相关(r=0.15**);对单株产量贡献最大的是每穗实粒数。垩白粒率和垩白度2个性状是杂交粳稻品质改良的重点,其次是精米率和整精米率;糙米率、精米率、整精米率相互间均呈极显著正相关,糙米率与垩白粒率和垩白度呈极显著正相关（r=0.33**,0.25**）。产量性状对品质性状的影响不大,通过筛选,可以将高产、优质的性状聚合到同一杂交组合中。     

甜玉米自交系性状相关分析和主成分分析

对30个甜玉米自交系的10个性状进行相关分析和主成分分析。相关分析表明,单株鲜穗产量与穗长、穗粗、行粒数、茎粗、株高、穗位高呈极显著正相关,与穗行数呈显著正相关;穗长与穗粗、穗行数、行粒数,穗粗与穗行数、行粒数呈极显著正相关;株高与穗位高、叶片数、茎粗、穗长、穗粗呈极显著正相关;行粒数与秃尖长呈极显著负相关。主成分分析结果表明:前4个主成分(产量因子、叶片数因子、秃尖长因子及穗行数因子)对变异的贡献率达86.85%。     

水稻品种绵香576产量结构分析及其高产栽培技术

对水稻绵香576的产量及其产量构成因素进行相关和通径分析,结果表明:构成绵香576产量的4个主要因素与产量呈正相关,有效穗数与产量相关系数达显著水平,其对产量直接通径系数也最大,对产量作用最大;有效穗数与每穗着粒数之间呈极显著负相关,且相互间接通径系数为负.在此基础上提出了主攻有效穗,同时兼顾结实率和千粒重,协调产量构成要素为重点的绵香576高产栽培技术要点.     

黑龙江省水稻根系性状与地上部性状的关系

为了探讨寒地水稻根系性状与地上部性状在不同生育阶段的关系,以黑龙江省的3个超级稻品种和3个普通品种为试验材料进行田间试验。结果表明,根长在不同的生育时期与结实率、各节间长、粗和粒数、一次支梗数呈正相关;根系体积与粒数、株高、与一次枝梗数和二次枝梗数在分蘖盛期为负相关,拔节孕穗期以后为正相关;根系干重在分蘖盛期与穗数呈极显著的负相关（r=-0.92**）,而与穗粒数、一次枝梗数和一次枝梗粒数均呈极显著的正相关的关系。根冠比在齐穗后与产量呈显著或极显著正相关（r=0.84*～0.96**）。     

Inter-relationships among cane yield and commercial cane sugar and their component traits in autumn plant crop of sugarcane

Seventeen diverse clones of sugarcane (Saccharum spp.) (7 early, 6 mid season and 4 late) were planted in October 1991 and 1992 in flooded (FE) and non flooded (NFE) environments for evaluation of cane yield, commercial cane sugar (CCS), internode length, internode number, stalk length, stalk thickness (circumference), stalk number, sugar recovery, and stalk weight. Cane yield showed significant positive phenotypic correlation coefficient (PCC) with stalk number in FE (P ≤ 0.05) and NFE (P ≤ 0.01). Stalk length had a significant positive PCC with stalk weight in both environments, and with internode length in FE (P ≤ 0.05). Commercial cane sugar also expressed significant positive PCC with cane yield in both environments (P ≤ 0.01), but with stalk number only in NFE (P ≤ 0.05). Genotypic correlation coefficients were generally in the same direction as PCC but higher in magnitude. In both environments, stalk number and stalk weight had relatively high positive direct effects on cane yield. However, flooding tended to enhance the direct effect of stalk weight and diminish the direct effect of stalk number on cane yield. Only cane yield and sugar recovery had high direct effects on CCS. Selection for improvement of cane yield can be based on stalk number and stalk weight in both environments. High yielding clones can be further screened for more sugar recovery to improve CCS. This revised version was published online in July 2006 with corrections to the Cover Date.     

用灰色关联法对11个甘蔗新品系主要数量性状与产量关联度的分析

为探索甘蔗主要数量性状对产量的影响程度，应用灰色关联度分析方法，对参加2005—2006年区域试验的11个甘蔗新品系的主要数量性状与产量的关联度进行了分析。结果表明：甘蔗主要数量性状与产量之间的关联度由高到低依次为公顷含糖量、茎长、茎径、萌芽率、单茎重、有效茎、分蘖率，说明甘蔗公顷含糖量和茎长是影响甘蔗产量的主要因素，为甘蔗育种提供了重要的理论依据     

肉苁蓉种子产量构成因子分析

为明确构成肉苁蓉种子产量的关键因子及其对种子产量的影响,采用相关、通径和多元回归分析等方法对肉苁蓉花部主要形态性状与单株种子产量的关系进行分析,得出与种子产量显著相关的7个构成因子为有效果数(X1)、总果数(X2)、单果种子数(X3)、花序长(X4)、大苞片长(X5)、结实率(X6)和花数(X7);其中有效果数(X1)对种子产量(Y)的直接效应最大,最优回归方程为:Y=-8.721+0.0919X2+0.00954X3。结果表明,肉苁蓉单株种子产量可以通过果数和单果种子数进行预测,打顶、增加授粉量以及选育种子高产品种等措施有助于种子产量的提高。研究结果为制定肉苁蓉的育种目标和栽培措施提供了科学依据。     

澳洲长鳍鳗各形态性状对体重的影响效果分析

随机选取澳洲长鳍鳗（Anguilla reinhardtii）1龄鱼50尾,分别测量全长、体长、背鳍长、臀鳍长、体高、头长、吻长、眼径、眼间距、口裂宽和体重共11个形态学指标。采用多元分析的方法,计算了以形态性状为自变量,体重为依变量的相关系数、通径系数、决定系数及相关指数。结果表明,除眼径和头长以外其他各形态性状与体重的相关性均达到了极显著（P<0.01）水平。剔除了通径系数未达到显著水平的变量,保留了全长、体高和口裂宽三个变量,其中全长对体重的直接影响最大（P1=0.398）。所选性状与体重的相关指数R2=0.965,说明所选性状是影响体重的主要形态性状。采用逐步多元回归方程法建立了回归方程为：Y=-1412.565+1.923X1+13.000X5+15.767X10。式中,X1、X5、X10分别为全长（mm）、体高（mm）和口裂宽（mm）,为澳洲长鳍鳗育种提供了理论依据。     

Genetic relationships between attributes in sugarcane clones closely related to Saccharum spontaneum

Summary Saccharum spontaneum is being used in sugarcane breeding programs in attempt to improve characteristics such as ratooning ability and stress tolerance. A population of F₁ (Saccharum officinarum or commercial variety x S. spontaneum) and F₁ x F₁ sugarcane clones was evaluated for sugar yield and a range of yield components in a plant and two ratoon crops. The aim was to determine genetic correlations between attributes in clones with a large component of S. spontaneum, that could be used to help derive appropriate selection indices in such populations.There were close associations between the same attributes measured in different crop-years and the associations between different attributes were generally similar across crop-years. Stalk number and fibre content were positively correlated, as were stalk weight and CCS. The latter two attributes (which are low in S. spontaneum but high in S. officinarum) were negatively correlated with the former two (high in S. spontaneum, low in S. officinarum). Sugar yield was more closely associated with stalk weight and CCS than with stalk number but became more closely associated with stalk number with successive ratoon crops.CCS was positively correlated (r_g=0.55) with cane yield in the plant crop but showed a small negative correlation with cane yield (r_g=–0.20) in the second ratoon crop. CCS (measured in any crop) also had a negative correlation with cane yield in the ratoon crops expressed as a percentage of plant cane yield. This suggests that CCS is negatively correlated with levels of traits contributing to ratooning ability. Intensive selection among such populations for CCS without consideration of ratooning performance may reduce the frequency of favourable specific ratooning characteristics.Abbreviations CCS commercial cane sugar     

123份棉花育种材料的综合评价分析

对123份棉花育种材料进行综合评价,旨在全面了解棉花主要性状间存在的关系。对产量、抗病性及纤维品质等性状进行相关性分析,并进行了纤维品质性状聚类分析。结果表明：（1）枯萎病、黄萎病病情指数、单株皮棉产量、子棉产量和单株铃数的变异系数较大,品质性状变异系数相对较小。（2）与子棉产量有极显著正相关的性状有6个,其中单株皮棉产量和铃重相关系数较高;上半部平均长度与整齐度指数相关系数为0.69**,与伸长率相关系数为0.78**;伸长率与断裂比强度相关系数为-0.62**,与整齐度指数相关系数为-0.63**。马克隆值与铃重相关系数最大为0.51**。（3）据品质性状聚类,123份材料被分为三类。研究为育种材料的杂交组配和培育高产优质抗病的棉花新品种提供理论和参考依据。     

Using logistic regression models for selection in non-replicated sugarcane breeding populations

Increasing selection efficiency in un-replicated populations has remained a challenge to sugarcane breeders due to the effects of genotype by environment interaction and competition among plots. Therefore studies aimed at exploring models to improve selection efficiency are required. At the South African Sugarcane Research Institute, the Stage II selection populations are planted to un-replicated plots. Visual selection, which is known to be subjective, is used to determine the genotypes advanced. Although path coefficient analysis has identified important yield components, there is little use of that knowledge to enhance selection. This study demonstrates the use of logistic regression model as a statistical decision support tool to enhance selection in un-replicated populations. The logistic regression model used stalk number, stalk height, stalk diameter and estimable recoverable crystal (ERC) % cane to predict sugar yield. The data were collected from Stage II populations across regional breeding programs and analysed using the logistic procedure of Statistical Analysis System. The Likelihood Ratio, Score and Wald statistics were highly significant (P < 0.0001) indicating the robustness of the models. Stalk number is the most influential component to sugar yield followed by diameter, height and ERC % cane. The coefficients of the yield components varied across different programs indicating the potential of the analysis to determine yield component combination. Genotypes selected using the models produced significantly higher trait values than those rejected. The logistic regression models should enhance selection efficiency in un-replicated populations as well as provide for the evaluation of breeding populations and trait combinations across regional breeding programs.     

西兰花苗期甜菜夜蛾发生危害与防治指标研究

根据2002-2008年西兰花基地甜菜夜蛾种群数量消长监测、高龄幼虫株虫量与致害株损失率关系和幼虫量与高龄幼虫量关系测定,结果表明甜菜夜蛾种群数量消长呈双峰型曲线变化,其高峰主要出现4-5月和8-11月,与田间西兰花生育期相一致;其苗期高龄幼虫株虫量与致害株损失率呈极显著线性相关,其相关回归模型：Y=23.126X+1.5803 (n=17,r=0.8075**)。应用防治得失和绿色防治原理测定经济允许损失为株害率3.09%（≈3%）,然后运用幼虫量与高龄幼虫量关系模型为：X=0.3204M+0.0378(n=17,r=0.8903**),拟定西兰花甜菜夜蛾防治指标为百株虫量20头。     

Limited contribution of water availability in genotype-by-environment interaction in sugarcane yield and yield components

Water deficit is an important abiotic stress factor limiting sugarcane production. Understanding the effect of water deficit on cane yield, yield components and genotype × environment (G × E) interaction can aid in selecting genotypes that are adapted to water deficit conditions. In this study, response of cane yield and yield components of 10 sugarcane genotypes grown under 3 irrigation treatments—fully irrigated, semi-irrigated and rainfed—was examined across 3 locations and 3 crop-years within each location. Cane yield reduced by 32% and 9% in the rainfed and semi-irrigated treatments, respectively, compared to the fully irrigated treatment. Genotypic variation was highly significant for cane yield and yield components in all three irrigation regimes. Cane yield in the rainfed treatment showed significant genetic correlation with stalk diameter (r_g = 0.68), leaf number (r_g = 0.64), node number (r_g = 0.67) and stalk number (r_g = 0.68). Genotype × irrigation variance was negligible compared to genotype, genotype × location and genotype × crop-year variances. Commercial genotypes had higher yield in most environments except in low-yield potential environments, which caused a significant genotype × location × irrigation effect, suggesting opportunities for improving sugarcane productivity in these environments.