春小麦是我县干旱山区的主要粮食作物之一。常年播种面积达十二万亩左右,占粮播面积的55％。但产量低而不稳,只占总产量的40.9—56.8％。平均亩产从1975年至1982年的八年间,除1976年达206.6斤外,其余七年均在100—166.5斤之间,低于全国、全省的水平。以1979年为例:我县山区小麦亩产仅为125.9斤,分别比全国、全省低82.5斤和119.5斤,年际之间产量摆动悬殊在百斤以上。其原因是多方面的。水是作物生长发育的主要生态环境因素。小麦生长的水分条件包括雨情和墒情两部分。土壤水是作物吸水的唯一直接来源,降水转化为土壤水后才能被作物吸收利用,但问题的实 Spring wheat is one of the major grain crops in the arid mountainous areas of our county. Perennial planting area of ​​about 120000 acres, accounting for 55% of the grain sown area. However, the output is low and unstable, accounting for only 40.9-56.8% of the total output. The average yield per mu from 1975 to 1982, eight years, with the exception of 1976 up to 206.6 pounds, the remaining seven years were between 100-166.5 pounds, lower than the national and provincial levels. Taking 1979 as an example: the yield per mu of wheat in our county is only 125.9 kg, 82.5 kg and 119.5 kg lower than that of the whole country and the province, respectively. The reason is many. Water is the main ecological and environmental factors of crop growth and development. Wheat growing moisture conditions, including rain and moisture two parts. Soil water is the only direct source of water for crops, after precipitation into soil water can be absorbed by crops, but the problem is