ABSTRACT
Citrus (Table 8.2) ............................................................ 161 8.15.2 Nutrient Recommendation for Citrus trees .................... 162 8.15.3 Soil Analysis ................................................................... 163 8.15.4 Leaf Analysis .................................................................. 163
Keywords .............................................................................................. 165 References ............................................................................................. 165
8.1 INTRODUCTION
Fruit trees and crop plants suffer from nutritional disorders. Nutritional disorders are a result of inadequate supply or excess of desired minerals/ fertilizer. The term macro and micronutrients are used to denote collectively group of mineral/nutritional chemical elements, which are indispensable for optimal growth and which plants absorb primarily through roots. Nitrogen, phosphorous and potassium requiring larger quantity are known as macronutrients while calcium, magnesium, iron, manganese, zinc, boron, copper, molybdenum, sulfur, etc. are known as micronutrients and require in smaller amounts. Deficiency of minerals viz. macronutrients and micronutrients, result in disorders in plant metabolism and plants express hunger signs viz. chlorosis, leaf spot, leaf blotch, leaf blight, dieback, reduced growth of tree, poor fruit quality and decreased number of fruits in citrus tree. Excess of mineral disturbs nutritional balance, which is most necessary for the proper metabolism in citrus tree. If the supply of minerals is high, trees show toxicity symptoms. Deficiencies and excesses of these minerals also reduce resistance of plants to fungal, bacterial and other diseases (Singh, 1983).
