在果树栽培上要提高每一个果实的重量,一般要受到果树品种遗传性的很大限制,所以要提高单位面积产量,主要在于增加单位面积内的果数。当前果树的座果率一般是很低的,多数在10％以下(见表1)。如黄岩柑桔一般只有2～3％,亩产20,000斤高产园,也,只有10％左右;苹果一般小于10％,只有部分品种高产的可达40％以上。如能使柑桔座果率提高2-3％;苹果提高10％,則果树产量可在原有面积上成倍地增加。因此,保花保果是我国果树生产的中心問題,在当前果树栽培条件下,最大限度地保花保果是农业“八字宪法”在果树栽培上具体应用的集中表現。自1958年大跃进以来,由于在苹果、梨、枇杷等果树生产上废除了疏花疏果的旧习慣,加强了栽培措施,出現了不少高产記录。如1959年中国农业科学院 In the fruit tree cultivation to increase the weight of each fruit, generally subject to genetic varieties of fruit trees is very limited, so to increase the yield per unit area, mainly lies in increasing the number of fruit per unit area. The current fruit tree fruit rate is generally very low, mostly less than 10% (see Table 1). Such as Huangyan citrus generally only 2 to 3%, 20,000 kg per mu yield of high yield garden, also, only about 10%; apples generally less than 10%, only some varieties of high yield up to 40%. If you can make citrus fruit rate increased by 2-3%; apple increased by 10%, then the fruit tree yield doubled in the original area. Therefore, the guarantee of flower and fruit preservation is the central issue of the fruit tree production in our country. Under the current fruit tree cultivation conditions, the maximum guarantee of flower and fruit preservation is the concentrated expression of the practical application of the “Eight Character Constitution” in fruit tree cultivation. Since the Great Leap Forward in 1958, due to the abolition of the old habit of thinning and thinning fruit trees in the production of apple trees, pears and loquat trees, cultivation measures have been strengthened and many high-yield records have emerged. Such as 1959 Chinese Academy of Agricultural Sciences