Can canopy management increase quality fruit production in Syzygium cumini (L.) Skeels?

Canopy management is a comprehensive strategy for orchard management which deals with the development and maintenance of tree structure in relation to the size and shape for the maximum productivity and quality. The basic concept in canopy management of a perennial tree is to make the best use of land and climatic factors for an increased productivity in a three-dimensional approach. Tree vigour, light, temperature and humidity play a vital role in the production and quality of fruits. However, understanding of plant nature and behaviour is essential, prior to canopy management, because the architecture of a plant depends on the nature and relative arrangement of its parts. Canopy density is determined by number and size of leaves, architecture of stem, branches and shoots. Syzygium cumini (L.) Skeels (popularly known as jamun) is an important fruit crop of the family Myrtaceae which prefers to grow from 32 degrees N to 30 degrees S latitude and can survive up to 1,800 m altitude. It is a tropical species preferring mean annual temperatures around 25-27 degrees C though will grow in sub-tropical areas, being sensitive to frost when young but mature trees have been undamaged by short frosts. The trees can reach a height up to 30 m with a broad crown up to 11 m in diameter and a trunk diameter of 0.6-0.9 m, though it usually has a multi-stemmed branching to the ground. Flowers appear in clusters, 2.5-10 cm long, each being 1.25 cm wide and 2.5 cm long. Fruits appear in clusters of just a few or 10 40, are round or oblong, often curved, 1.25-5 cm long. Fruits are hand-plucked as the peel is very thin. It is thus necessary to climb the tree for harvesting. Besides in high density orchards, trees lose production on the lower tier of branches due to the shading effect. It is therefore necessary to manage the tree canopy by pruning to restrict tree growth which will facilitate the harvesting without affecting the yield level. Crop load management is also most important in canopy management that determines the annual profitability of orchards. Thus, effectiveness of different components of canopy management is measured by their influences on light interception and distribution, thereby affecting productivity of quality fruits in an orchard. Although, few researches have been initiated in India on canopy management in jamun by adopting open centre and palmette system of training, however the concluding remarks about these systems are yet to be drawn so as to identify the suitable system of training for improving canopy productivity. Research on canopy management should assess the impact of pruning on flowering, light interception and distribution within the canopy and the leaf area supporting the developing crop. Since jamun trees often grow quite vigorously, effective canopy management strategies need to be developed that can be readily integrated into high-density growing systems.