在介绍几类主要果树对营养元素的具体需求之前,我们首先对果树作物进行泛述。在欧洲南部地中海的气候条件下,钾对一年生农作物的影响不象氮那样容易看出。然而对多年生果树却相反,钾对果实的影响是显而易见的,如着色好、果形大、果皮美观等。这些影响大都易于在缺钾的土壤上显示出来。人 Before describing the specific nutrient requirements of several major fruit trees, we first outline the fruit crop. Under the climatic conditions of southern Mediterranean Europe, the effects of potassium on annual crops are not as readily apparent as nitrogen. However, on the contrary to the perennial fruit tree, the effect of potassium on the fruit is obvious, such as good coloring, large fruit shape, beautiful peel and so on. Most of these effects are readily apparent in K-deficient soils. people