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从二十几年来的栽培历史看,西安地区大白菜大面积丰产的年份亩产可达1万多斤,高产田块亩产2万多斤;歉收年大面积亩产5,000—6,000斤;平年一般亩产8,000斤上下。产量不稳定,是当地大白菜生产上的大问题。气象灾害是产量不稳的一个重要因素。在1951—1960年的十年中,多数是雨涝年份,出现了较多的歉收年;1961年以后的十几年中,多数是较干旱的年份,产量较稳定,一般为丰收年或平收年。但也有的年份由于8月间长期高温干旱而造成了严重减产。灾害性天气除直接给大白菜生产造成一定的困难外,常易引起病害(病毒病、霜霉病、软腐病)的严重发生,这是造成大白菜减产的主要原因。
According to the past 20 years of cultivation history, the annual yield of large-yield cabbage in Xi’an is up to 10,000 kilos per mu and the output of high-yield plots is 20,000 kilos per mu; General mu produce 8,000 pounds up and down. Unstable yield is a big problem for local cabbage production. Meteorological disasters are an important factor in unstable production. During the decade from 1951 to 1960, most were flood years, with a large number of poor harvest years; most of the ten years after 1961 were drier years with more stable output, generally a bumper harvest year or a flat Year. However, there are also some serious year-on-year reductions due to prolonged high temperature and drought in August. In addition to causing some difficulties directly to the production of Chinese cabbage, disastrous weather often causes serious occurrence of diseases (virus diseases, downy mildew and soft rot), which is the main reason for the decrease of yield of Chinese cabbage.