(一)我区推广杂交玉米是从一九六五年开始的。当年春天,从山西、山东引进了一百多斤玉米杂交种进行试种,表现很好,一般亩产八百多斤,增产显著。此后,推广面积迅速扩大。一九七一年达九万多亩,总产量比一九七○年增加了百分之四十六,亩产由一九七○的三百六十斤上升到四百四十五厅,增产百分之二十四。一九七二年推广面积达到二十二万多亩,占全区玉米总面积的三分之一。閬中、武 (A) The promotion of hybrid corn in our district started in 1965. In the spring of that year, more than 100 kilograms of maize hybrids were introduced for trial planting from Shanxi and Shandong. The performance was very good. Generally, the yield was more than 800 kilos per mu, a significant increase. Since then, the promotion of the rapidly expanding area. In 1991, it amounted to 90,000 hectares. Its total output has increased by 46% over that in 1970. The yield per mu has risen from 366 jins in 1970 to 454 halls, Twenty four percent increase. In 1972, the popularized area reached 220,000 mu, accounting for one-third of the total corn area in the region. Langzhong, Wu