MANGO, the king of fruits is the second major fruit which also has a good demand in foreign markets. Over 100 evolved varieties are under commercial cultivation.

Mango trees, less than 10 years of age give flower and fruit every year. Thereafter, most varieties tend toward alternate, or biennial, bearing.

Traditionally, all parts of a mango tree trunk, branch, twig, leaf, petiole, flower and fruit are attacked by a number of insect pests and pathogens including fungi, bacteria and algae.

Mango hoppers, thrips, borers, mites, fruit flies, mealy bugs, weevils, scale insects and honeydew (excrete on leaves and flowers giving rise to sooty mold), 14 types of mango galls (12 occurring on the leaves), are easily diagnosable enemies of the tree and fruit because of their visible occurrences.

Mango also suffers from several pathogenic diseases at all stages of its life and causes several kinds of rot, die back, anthracnose, scab, necrosis, blotch, spots, mildew, etc. It is difficult to see and identify the causal agent because of their microscopic size.

Growers, contractors, labourers working in orchards are still worried about the issue which is under investigation since the last 10 years. Tree mortality or death problem has now become very serious in Sindh, especially around Hyderabad, Tando Allahyar and Matiari districts.

The issue is under discussion from the grower, contractor and researcher to the high-powered committees and commissions of policy makers, for final decisions regarding identification of cause and control of the disease. The most destructive problem is ‘Quick decline’ or ‘Sudden death’ or ‘Tree mortality’ and is referred by scientists as the ‘Mango Tree Mortality (MTM)’ or the ‘Mango Sudden Death Syndrome (MSDS)’.

Mango trees have a long life and according to world record, some specimens are 300 years old but still give fruit. Age may be a cause of mango tree death but many die young. The problem is recorded in newly developed seedling plants and young fruiting trees.

Thousands of mango trees are now dead placing Pakistan at the sixth position in the world as compared to the time when it was third after India and China. Mango industry is hard hit due to the decline/death of the trees in many countries of the world, including Pakistan, near about in a similar way.

Pakistani scientists are now working in collaboration with their overseas counterparts to find a cause of fast-dying mango trees and the ways to protect them. The problem which is being discussed here occurred in Hyderabad district where the orchards of Gul Muhammad Jiskani, Village Tanwor Jiskani alias Jhooro Patel, near Tandojam and others exist. Mango trees are suffering from another problem ‘ball formation’.

A survey of thousands of mango orchards revealed that a variety ‘Rataam’ (as named by the grower Gul Muhammad Jiskani) was found affected. The affected trees are under observation since the last two years. The ball pattern has remained similar with only number and size of the balls increasing slowly. There is no more loss to the affected trees. These ball shaped galls are stuck/adhered on primary and secondary stems in scattered pattern. When these are broken, the round woody balls were found covered with similar to normal skin (bark) with red ink like solution scattered at the centre point of broken woody ball. This is not a varietal character as symptoms are present in some while absent in other trees of the same variety. As the problem is not serious hence it is not noticed even by the grower. What would be done if it spreads like other pathogenic problems? Immediate attention on the issue is sought.

After the review of literature with reference to protection, it has come to the notice that this is the first time that over grown ball-shaped mass like tumours or knots or galls on mango trunk/stem and branches were observed which previously were not reported. These are clearly different from the previously reported crown gall or stem gall.

According to literature, crown gall is caused by the bacterium Agrobacterium tumefaciens. Galls vary in size and texture. They are generally much smaller on roots than on the crown or collar; on herbaceous stems they are usually soft but are always hard on woody stems. The bacteria are found mainly toward the outside of galls and are readily isolated from scrapings of the peripheral tissues. Infection occurs only through a wound.

Insect galls show extreme diversity of form, and there are a great many insects which cause them. Some midges are associated with the fungi in galls called ‘ambrosia galls’.

The nematode, Meloidogyne spp. also produces galls/knots on their hosts which vary in size but occurs on roots and differ little in shape. Mango ball formation is different to bacterial, insect and nematode galls.