梨幼树干基湿腐病主要侵染梨幼树植株,使主干基部的皮层至木质部组织变褐坏死,造成全株生长衰弱,枝干枯死。该病害在我省五十年代就有发生,六十年代以来全省主要梨产区普遍发生,尤以陇中、河西地区最为严重,是我省梨树栽培中急需解决的问题。自1979年以来,我们在全省范围内进行了调查,并就其发生条件及防治措施开展了试验研究。其主要结果如下: 一、主要症状病害首先出现在主干基部的近地面下部,使皮层或周皮变褐黑色,继后逐渐深入至形成层干表,呈现出黑色病疤,患病段干径变细,干缩凹陷,逐渐形成环状绞隘。病害由下向上渐 Pear young stem-based wet rot mainly infects the young saplings of young pears and causes browning and necrosis of the cortex of the basal part to the xylem tissues, causing the whole plant to grow weak and the stems to die. The disease occurred in the fifties of our province. Since the 1960s, the main pear producing areas in the province have been widespread, especially in Longzhong and Hexi areas, which is an urgent problem to be solved in pear cultivation in our province. Since 1979, we conducted a survey within the province and carried out experimental studies on the conditions in which they occurred and their prevention and control measures. The main results are as follows: First, the main symptoms of disease first appeared in the base of the trunk bottom of the ground near the cortex or perineum brown, and then gradually deepened to form a dry table, showing a black scars, disease diameter Narrow, dry shrinkage depression, and gradually form a ring twist. Disease from the bottom up gradually