Diseases and Disorders of Mango and their Management

Abstract

The mango (Mangifera indica Linn.) is an important fruit crop in India and other tropical and subtropical countries of the world. It is grown in at least 87 countries but no where it is so greatly valued as in India where 40 per cent of total fruits grown in our country is only mango. Although India is the largest producer of mango but in terms of productivity, it ranks sixth. The low productivity is mainly due to the associated disease problem. Mango is affected by a number of diseases at all stages of its development, right from the plants in the nursery to the fruits in storage or transit. Hardly any plant organ is immune and almost every part viz. stem, branch, twig, root, leaf, petiole, flower and fruit are affected by various pathogens, yet there are few diseases which are of great economic importance. These diseases manifest themselves as several kinds of rot, die back, mildew, necrosis, scab, blotch, stem bleeding, wilt, spots, canker, sooty mould and malformation. Leaf spot diseases cause great loss and hamper the efforts made to increase the yield of mango tree. They impoverish the leaves, diminish the phyto-synthetic efficiency and upset normal physiological activity of the host. Some of these diseases take heavy toll of trees, and have become limiting factor in mango cultivation in some regions. Bloom blight or Blossom blight in some years causes a complete failure of the crop. Other diseases like bacterial canker, black tip, powdery mildew, sooty mould and die back in India are the sources of great loss to the orchardists. The chemical based strategies have been so far dominating for management of mango diseases but it has caused serious imbalance in the agro-ecosystem. Strangely, about 70 percent of the amount of sprayed chemicals, does not stick to the plants. Enormous quantities of chemicals that fall on to earth get mixed up with soil adversely affect microbial life. Some problems like nontarget effects of chemicals as well as chemical induced diseases are being experienced. A shift towards nonchemical strategies is likely to correct the imbalance in our approach. The most logical approach is known as IDM, which is being used for few important diseases of mango and discussed in this chapter.