柑桔叶片矿质营养与产量的相关性

对5个柑桔品种叶片矿质营养元素进行了测定,在年周期中呈现规律性变化。1月花芽形态分化期,叶片氮、镁含量与产量呈显著或极显著正相关,提出福建山地柑园土壤中盐基成分流失严重,叶片缺钙、镁、钾较普遍,需肥顺序是钙>镁>钾>磷>氮.

Studies on Relationship Between Fruit Yield and Mineral Elements in Leaf of Citrus

The experiments were carried out from 1978 to 1988.Five citrus varieties,namely Nan-fenmiju,Fuju(C.tangerina),Satsuma madarin,Ponkan and Sweet orange,were applied.The result of the experiment was shown as follows:1.The contents of mineral elements in every citrus variety changed regularly in growthseason:The nitrogen content in the leaf was highest in the physiological floral bud differenti-ation stage(from Sept.to Oct.);and was lowest in the morphological floral bud differentia-tion stage(Jan.).As to contents of phosphorous and potassium,the highest was in theleaves growing in May,and decreased with the age of the leaves.Conversely,calcium con-tent increased with the age of the leaves:While magnesium content appeared the lowest inthe young leaves(May)and then increased gradually to reach the peak in Sept.or Oct.Afterthat,decreased gradually.2.In the morphological floral bud differentiation stage,the contents of nitrogen andmagnesium in the leaves was significantly correlated with fruit yield.The correlation coeffi-cient between nitrogen and fruit yield in various varieties were:0.7051 in Ponkan,0.9091 inFuju,0.8758 in Nanfenmiju,O.9125 in Satsuma mandarin,and O.6429 in Sweet orange.3.Because Fujian located in the subtropical zone with high temperature and abundantrainfall,the minerals in red soil orchard in Fujian was easy to be washed away,the calcium,magnesium and potassium were generally deficient.