&lt;p&gt;Orange fruit has a prominent place among popular and extensively grown fruits, occupying nearly two-third of the world&amp;rsquo;s total area under fruits crop. However, it occupies only 10 per cent of the total area under all fruit crops in India, with third rank after mango and banana, covering an area of 4.88 lakh hectares with annual production of 46 lakh tonnes.&lt;br /&gt;
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Orange leaf has special physiological characteristics, with impervious layer on upper side of the leaf and with a large number of small openings on lower side of the leaf, known as stomata. Through these openings pests and diseases entered in the leaves of orange tree and destroy the tree. Therefore, for effective pest and disease control spraying should be done at lower side of the leaves only.&lt;br /&gt;
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In many parts of India, orchard spraying is carried out by Foot, Rocker, Hydraulic sprayers and spray guns. For effective spraying these sprayers requires high amount of spray liquid, high-energy consumption, more time, labour and money. Air carrier sprayer uses an air blast with a very velocity to carry the spray droplets on lower side of the leaves. The main aim of this project was develop the suitable air carrier sprayer for spraying in orange orchard.&lt;br /&gt;
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In the laboratory, newly developed sprayer was tested. It was found that the axial flow blower of the sprayer gives the maximum efficiency of 34 per cent at 2500 rpm and air velocity of 18.8 m/s. The sprayer was tested in the orange orchard at various system pressures and travel speeds to evaluate its filed performance. System pressures and travel speed both has a significant effect on the deposition of spray liquid. Considering all factors, for effective spraying system pressure of 12 kg/cm2 and travel speed of 2.0 km/h is required.&lt;/p&gt;
