Review on Effect of Shade Tree on Microclimate, Growth and Physiology of Coffee Arabica: In case of Ethiopia

The word "coffee" comes from the name of a region in Ethiopia where coffee was first discovered -'Kaffa'. The name 'Kaffa' is inherited from the hieroglyphic nouns 'KA' and 'AfA'. 'KA' is the name of God; 'AFA' is then ame of earth and all plants that grow on earth. So the meaning of Koffee (Coffee) from its birth-place bells on as the land or plant of God. In addition to this, as a result of the genetic diversity of Ethiopian coffee, botanists and scientists agree that Ethiopia is the centre for the origin, diversification and dissemination of coffee plant According to Climatic factors, type of soil, mulching, farm management method, crop production methods, etc. are among the prominent factors that affect the growth and development of plants including coffee. Amongst the various factors for having a good yield of coffee is growing of shade trees with the coffee plant which has a great contribution on both the life span of the coffee trees and its yield forage trees, fruit, nut trees, etc.) as shade, shelterbelt and windbreaks, for beautifying residential areas, and serve Abstract: The seminar work conducted to review the effect of shade tree on microclimate, growth and physiology of coffee plants. To achieve this reviewed, microclimate, growth, and physiology of coffee plants growing under shade trees were compared with those of coffee plants growing under direct sun light. Different physiological,, growth parameters ,and microclimate environmental effect reviewed. Shade trees protected coffee plants against adverse environmental stresses such as high soil temperatures and low relative humidity. The light intensity in coffee declines under shade and that this depends on the shade tree species. The major effects of shade trees on the microclimate experienced by coffee plants can be summarized as a reduction in transmitted light and an improvement in microclimatic conditions through a reduction of air and coffee leaf temperature extremes. The higher growth in the shade plants from internodes elongation that was induced by low irradiance. The shade increased the number of node . The number of flowers branch between un shade and shade is affected by location of canopy. The fruit fall under shade was less than that of coffee grown in full sun. Coffee performs best when grown under suitable shade tree species with properly designed cropping system however, shade also triggered differences in physiological behavior of the coffee plants, such as improved photosynthesis and increased leaf area index, resulting in better performance than possible in direct sun light. Consequently, coffee plants grown under shade trees produced larger and heavier fruits with better bean quality than those grown in direct sun light. Moreover, shaded plants had greater biochemical and physiological potential for high dry matter production which would help them to maintain high coffee yields in the long term. If growing coffee under shade trees would allow other sources of income such as fruits, fuel wood and timber to be produced, it could be socially more acceptable, economically more viable and environmentally more sustainable. In this reviewed of literature I can recommended that of growing coffee in the shade had better performance and suggest that the future reviewed should be directed toward deterring the development of fungal diseases and increase of coffee yields under shaded conditions