一、前言母生是海南特类用材树种之一。解放后,在党的正确领导下,各地营造了大面积的母生林。这些人工林多数初期生长迅速,生势旺盛。但郁闭以后二、三年内,有一部分生长显著缓慢,树冠逐渐变小,生势逐渐衰退,有的地区还出现一些枯死现象。因此成为当前生产上急待解决的问题之一。为了配合幼林叶片培养诊断工作、进行苗木主要矿质培养元素缺乏的人工培养试验,研究矿质营养缺素症状及其对生长的影响,为幼林的观察分析提供依据。 First, the foreword mother is one of Hainan special timber species. After the liberation, under the correct leadership of the party, large-scale mother forests were built around. Most of these plantations are rapidly growing and gain vigorous growth. However, within two or three years after its closure, some of its growth slowed noticeably, its canopy gradually became smaller, its growth gradually declined, and some areas withered up. Therefore, it becomes one of the urgent problems to be solved in the current production. In order to cooperate with the diagnosis of young leaves, we conducted the artificial cultivation experiment of lacking the main mineral culture elements of seedlings, studied the symptoms of mineral nutrient deficiency and their effects on the growth, and provided the basis for the observation and analysis of young forest.