Litchi (Litchi chinensis Sonn.), is an important sub-tropical evergreen fruit crop of excellent quality, belonging to family sapindaceae. The sapindaceae is a relatively large family containing at least 125 genera and 1,000 species, which are widely distributed in the tropics and warm sub-tropics. Litchi is believed to have originated in southern China, where it has been cultivated for over 4000 years.Low and irregular bearing is a hurdle in successful cultivation of litchi which is preventing litchi from becoming the major crop of subtropical region so far.The problem is generally due to...