华南荔枝和龙眼叶片营养状况诊断及分析

Analysis and Diagnosis of Leaf Nutrient Statuses for Lithic and Longan in Southern China

利用荔枝和龙眼叶片营养诊断指标,对华南主产区22个荔枝园及8个龙眼园在2016—2019年不同生育期的叶片大中微量元素营养状况进行了研究和诊断。结果表明,荔枝龙眼叶片养分含量在不同年份的同一生育期间、同一年份的不同生育期间及同一年份同一生育期不同树之间的差异均很大。其中,微量元素含量差异大于中量元素的,而后者又大于大量元素的。荔枝龙眼叶片各种养分的含量属于适宜等级的基本均不足一半,叶片营养缺乏和过量的情况普遍存在。荔枝叶片N含量主要表现为不足,P、K往往过量,而中微量元素含量低于及高于适宜水平的比例接近。龙眼叶片N含量普遍过量,P、Ca、Mg主要表现为不足,叶片Mn、Cu、Zn、B则普遍缺乏。在荔枝龙眼进行叶片营养诊断,及时调整施肥方案,平衡树体营养,不但必要,而且是获得荔枝龙眼高产稳产优质的重要技术手段。

Leaf nutrient statuses of litchi and longan at various growth stage during 2016-2019 from 22 litchi orchards and 8 longan orchards respectively in southern China were investigated and diagnosed.The results showed that great discrepancy was observed for leaf nutrient contents between the same growth stages of different year,between different growth stages of the same year,and between different trees even at the same growth stage of one year.Generally,the variation of foliar micronutrient contents was greater than that of foliar secondary nutrient levels,and the latter was higher than that of the macronutrient values as well.The percent of leaf nutrient content classified as proper grade was commonly lower than 50%.The deficiency and excess of a nutrient coexisted extensively in both litchi and longan.litchi The leaf was commonly lower in N,whereas excessive in P and K.Andthe percent of deficiency grades of the secondaryand micro-nutrients was similar to that of excess grade of themselves in litchi.Foliar N was generally excessive,but foliar P,Ca and Mg were lower,and foliar Mn,Cu,Zn and B were deficient in longan.In conclusion,it is necessary to undertake foliar nutrient diagnosis in litchi and longan,in order to rapidly regulate the fertilization strategy and balance the plant nutritional status,which is important to achieve high and stable fruit yield and excellent fruit quality.