In commercial mango, litchi and coconut orchards, fertiliser is applied as it should be, but farmers often cannot spray large trees properly to control pests and diseases. The knapsack sprayers and hand compression sprayers used for vegetables, rice and pulses in open fields are unsuitable for large fruit trees such as mango, litchi, coconut and jackfruit, and for wide-canopied guava, sapodilla, jujube and lemon trees. Yet farmers use the same sprayers, so even when insecticides, fungicides or growth hormones are applied, they have no effect; pests and diseases are not controlled and costs simply rise.

Farmers should consider several things before buying a sprayer for an orchard. An orchard is a long-term profitable investment, like a fixed deposit or monthly income scheme, and the machine you buy is also meant to be used efficiently for a long time. Thinking these issues through in advance makes it possible for fruit growers and those who lease orchards to buy suitable equipment for pest and disease control.

Hand knapsack sprayers and their improved "hi-tech" versions are mostly used for field crops. They are operated by hand, building pressure to release the spray, and some versions are driven by battery, electric or fuel-powered motors to spread solution finely over a larger area in less time. But farmers who use these sprayers on fruit trees will not get the results they expect. They can protect small fruit crops such as pineapple, banana and papaya, but they are unsuitable for most orchards of mango, litchi, guava, jackfruit and coconut. To spray evenly all around tall fruit trees, another type of sprayer must be chosen.

Source: Staff Correspondent, The Agro News. First published in Bengali on The Agro News.