摘要
近年来,我们对长江下游地区的小麦产量和育种目标初步进行了一些典型调查。从小面积高产栽培来看,需要一些亩产稳定在千斤的品种。目前长江下游地区推广的一些小麦品种中,亩产800斤以上潜力的为数不少,但有否可能以这些品种为基础,从中进行选择,育出一些在某几个方面有所改进的新品种,需要对这些品种群体的遗传变异作必要的研究。而要了解这些高产小麦品种群体各种性状的遗传变异程度,需要采用遗传方差的分析,估计出遗传方差、遗传变异系数和遗传力等遗传参数。
Seven high-yielding varieties of wheat(Triticurn aestivum L.)grown in the Lower Yangtse Valley were used in this study to investigate the hereditary variations of four yield component characters and plant height.Four row plot with 4 replications in a dibble seeding were studied to determine the genetic variation coefficients(GCV),broadsense hereditabilities,relative genetic advances(GS’),genotypio correlations and selection indexes.The broad-sense hereditability estimates are high for plant height and number of grains per spike,moderate for spikes per plant,and low for weight of 1,000 kernels and grain yield per plant.The GCV are higher for spikes per plant,moderate for the number of grains per spike,and low for plant height.Since the hereditability estimates and GCV for spikes per plant and the number of grains per spike were higher,single plant selection on these two characters from the 7 varietal populations would be effectual.The magnitude of relative genetic advance predicated by the population of 7 wheat varieties showed that the spikes per plant had higher GS’,number of grains pet spike and grain yield per plant had median GS’,the weight of 1,000 kernels and plant height had lower GS’.The number of grains per spike was positively and significantly correlated with grain yield per plant.Weight of 1,000 kernels was negativly and significantly correlated with the spikes per plant.The genotypic and phenotypic variances and covariances entering into the computation of the correlations were used to illustrate the construction of selection indexes in wheat.Various selection indexes were constructed and the expected genetic advance from the use of each was determined.The relative efficiency from the use of the various selection indexes compared with selection for single plant grain yield alone.The efficiency of selection index for single plant yield with single correlated character was not high enough,but with two or more characters included the efficiency was well raised.When a selection index includes the single plant yield itself and other correlated characters,its efficiency is better than that without the single plant yield.
作者
俞世蓉
魏燮中
夏奇梅
罗玉春
Yu Shirong;Wei Xizhong;Xia Qimei;Luo Yuchun(Laboratory of Wheat Varieties,Nanjing Agricultural College,Nanjing)
出处
《中国农业科学》
1982年第4期13-19,共7页
Scientia Agricultura Sinica
基金
吴兆苏教授主持的“小麦经济性状的相关和遗传研究”课题的一部分
