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据市场调查,1998年廊坊市大白菜市场供应严重不足,品质低劣,棵小、包心松散、烂疙瘩,可大白菜价格昂贵,每公斤高达1.4元左右,是过去几年大白菜价格的4～6倍。菜农普遍反映经济效益很低,原因是软腐病发生严重,亩产量比常年减少一半以上,甚至有些地块全部绝收,分析其主要原因有如下几点。一、气候条件有利于秋季大白菜软腐病发生我市气象局提供资料:1998年9月下旬平均温度为21.7℃,比1997、1996年同期高3.4℃,10月上
According to market research, in 1998 Langfang City, a serious shortage of Chinese cabbage market supply, poor quality, small trees, loose heart package, rotten knots, cabbage can be expensive, up to 1.4 yuan per kilogram, the past few years the price of cabbage 4 ~ 6 times. Vegetable farmers generally reflect the low economic benefits due to the serious occurrence of soft rot, the yield per mu is reduced by more than half over the previous year, and even some of the plots are totally unacceptable. The main reasons for the analysis are as follows. First, the climatic conditions conducive to fall cabbage soft rot disease City Meteorological Bureau to provide information: the average temperature in late September 1998 was 21.7 ℃, higher than the same period in 1997,1996, 3.4 ℃, October