Mangoes Disorders

Mangoes Disorders

Mangoes Disorders (4)

Black tip is a serious disorder, particularly in the cultivar Dashehari. The affected fruits become unmarketable and reduce the yield to a considerable extent. Black tip disorder has generally been detected in orchards located in the vicinity of brick kilns.

  • Planting of mango orchards in North-South direction and 5 to 6 km away from the brick kilns may reduce incidence of black tip to a greater extent.
  • Spraying borax (1%) or other alkaline solutions like caustic (0.8%) or washing soda (0.5%) is also effective. The first spray of borax should be done positively at pea stage followed by two more sprays at 15 days interval.

Despite high fruit set initially, the ultimate retention is quite low in mango. The intensity of fruit drop, varies from variety to variety. Among the commercially grown varieties, Langra is more susceptible to drop while Dashehari is the least. The fruit drop is more or less a continuous process and can be classified into three groups : (i) Pinhead drop, (ii) Post-setting drop and (iii) May-month drop.

Embryo abortion, climatic factors, disturbed water relation, lack of nutrition, disease, pest and hormonal imbalances are the major factors that lead to fruit drop.

The term biennial, alternate or irregular bearing generally signifies the tendency of mango trees to bear a heavy crop in one year (On year) and very little or no crop in the succeeding year (Off year). Most of the commercial varieties of north India, namely, Dashehari, Langra and Chausa are biennial bearers. The problem has been attributed to the causes like genetical, physiological, environmental and nutritional factors.

For overcoming biennial bearing, de-blossoming is recommended to reduce the crop load in the ‘On’ year such that it is balanced in in the ‘Off’ year.

Soil application of Paclobutrazol (PP333) or @ 4 - 5 g per tree (amount varies with the age of trees) in the month of September resulted in early flowering with higher fruit set and yield. It may be applied every year for regular fruiting, particularly in young trees.

Malformation is widely prevalent in northern India. The malformed panicles remain unproductive and are characterised by a compact mass of male flowers, greenish in colour and stunted in growth. Some remedial measures are recommended as follows :

  • Pruning of shoots bearing malformed panicles
  • Deblossoming of early emerged / infested panicles.