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Causes of the 1999 yield reduction of Jin jujube in Ning County and the solutions
Jin jujube cultivation in Ning County, Gansu Province is concentrated in Zaosheng Town. In 1999, the bearing area was 100 hectares, with a total yield of 212.5 tons, which was 22.3 tons less than the average over the years, a reduction of 12.5%, making it a year with relatively poor yield in history. I. Causes of the Jin jujube yield reduction 1. Severe jujube witches' broom disease: According to a survey conducted in Xinzhuang Village, Zaosheng Town, Ning County, before 1997 the rate of diseased plants of jujube witches' broom accounted for 3.98% of the total number of trees, and all diseased trees were fruit-bearing trees. By 1999, the number of trees with jujube witches' broom had risen to 1387, accounting for 10.05% of the total