材料和方法 主要以解放以来太湖地区四个不同年代推广种植的水稻改良品种为对象,了解性状演变趋势。1984,1985年水稻生长季节,选用了解放后本地区不同年代推广的20个代表品种,如50年代有412,853,老来青,老虎稻;60年代有桂花黄,沪选19,嘉农33;70年代有南粳33,旗粳52,苏粳2号,农虎3-2,农虎6号,昆农选16,农桂早3-7,昆稻2号;80年代有盐粳902,紫金糯,早单八,测21,8227等,随机区组,三次重复。六行区,行长2米。单本栽,株行距16×16厘米。5月16日播种,6月19日移栽。 抽穗期、成熟期分别于小区随机取样2穴,测定单株叶面积和各叶、鞘干重;抽穗期用量角器 Materials and methods are mainly targeted at modified rice varieties popularized and popularized in four different regions of the Taihu Lake region since the liberation to understand the evolution trend of traits. In 1984 and 1985, during the growing season of rice, 20 representative cultivars popularized in different regions of the region after their liberation were selected. For example, there were 412, 853, Laolingqing and Tiger rice in the 1950s; In the 1970s, there were Nanjing 33, Jingjing 52, Sujing 2, Nonghu 3-2, Nonghu 6, Kunnong 16, Nonggui 3-7 and Kun’ao 2, and Yanjing 902 in the 1980s , Zijin waxy, early single eight, measured 21,8227, randomized block, three times repeated. Sixth district, the governor 2 meters. Single plant, plant spacing 16 × 16 cm. May 16 sowing, June 19 transplanting. At the heading stage and the maturity stage, 2 points were randomly sampled in the plot, and the leaf area per plant and the dry weight of leaves and sheaths were measured.