Growth Correlations and Assimilate Partitioning in the Arillate Fruit of Litchi chinensis Sonn

Abstract

Path analysis and partial correlation methods revealed a direct positive effect of the peel and seedcoat on the size of the aril, and also the positive partial correlations among these three variables. A negative partial correlation between embryo and aril, and a direct repressive effect of the former on the latter were confirmed. The embryo does not by itself stimulate peel growth but, by extending seed life, it results in a higher frequency of large-sized peels. The existence of the three types of fruits with or without an aril and/or embryo results from the disparity in the life-span of the liquid endosperm. The aril is inferior to the embryo in competing for assimilates. Aril growth is mediated by both the concentration of solutes accumulated in the vacuoles creating a more negative osmotic potential, and the restricting force coming from the peel which increases the pressure potential.