【摘要】 <正> 长江下游地区是我国最主要商品小麦生产基地之一。建国以来,本地区小麦的总产与单产都得到大幅度的增长,就江苏省淮南片而论,五十年代初期平均亩产仅约100斤,近年来已上升到500斤左右。在增产措施中,推广丰产良种起了重要作用。今后进一步发展小麦生产,还需要选育和推广增产潜力更大的新良种。掌握本地区先后种植的品种产量潜力递增情况,将有助于今后的选育工作。已有的关于本地区历来种植的品种的更多还原

【Abstract】 Yields of wheat in the Lower Yangtse Region have risen quite spectacularly over the last thirty years. Such increases in yield have been due predominantly to a variety of genetic changes effected by wheat breeders. This study reviews the changes in yield and related characters of wheat cultivars grown in this region since 1950 and seeks to define the direction from which further advances may be possible in the future.15 cultivars, representatives of current and preceded ones, were grown in a 3—replicate, randomized block layout in 1981—1982 season, and were evaluated for grain yield, biomass, yield components, plant height and other characters.The mean yield, yield components, and harvest index of current cultivars were significantly greater than those of the preceded ones. The plant height and lenghth of internodes of the former were significantly shorter than the later.The genetic correlation coefficients showed that plant height was negatively and highly correlated with grain yield, harvest index was positively and highly correlated with it,and biomass was positively yet less correlated with it. The number of grains per square meter, per spike and per spikelet, and fertile spikelets per spike were positively and highly correlated with grain yield, yet kernel weight and spike number per mu were slightly positively and negatively correlated with it respectively.It is interesting to have found that the proportion of any internode length to the total length of it and its adjacent lower internode, which was denominated the plant height component index, was positively and highly correlated with grain yield.Results form this study suggest that further yield advances could be attained by combining higher biomass and higher harvest index,shorter straw and higher plant height component index, greater number of grains per spike and higher kernel weight associated with higher grain-filling rate in breeding programmes.更多还原