我们小堡畜牧场的千金果园有苹果树3300株,其中锈果病树54株,占34年生树2673株的2.02％。这些病树年产量仅万余斤,加上质量差卖价低,与同数量的健树相比,每年少收入3000余元。为控制锈果病的为害,我们从1980年开始进行了防治试验。 There are 3300 apple trees in Qianqi orchard in Xiaobei livestock farm, of which 54 are rust-fruit trees, accounting for 2.02% of 2673 trees in 34-year-old trees. The annual output of these diseased trees only ten thousand pounds, together with the poor quality of low prices, compared with the same number of health trees, less annual income of 3,000 yuan. To control the rust damage, we started the prevention and control test in 1980.