Importance of Seed Reserves in Arbuscular Mycorrhizal Formation and Growth of Azadirachta indica A. Juss.

Abstract

Seedling development and their survival in nutrient deficient soils depend on the seed reserves. Here, we attempted to understand the role of seed reserves on arbuscular mycorrhizal (AM) formation and development of neem (Azadirachta indica AJuss.) seedlings. The neem seedlings were grown with intact, partial and without seed reserves. Partial or total of seed reserves removal reduced seedling growth, tissue nutrient concentrations and AM formation. Further, excision of one or both cotyledons generally reduced chlorophyll, carbohydrate, protein, and lipid contents. However, cotyledon excision increased phosphate use efficiency (PUE) and phosphate efficiency index (PEI), except at 90 days. Specific absorption rate of nutrients was low initially in seedlings, without seed reserves; but was higher during the later stages of seedling growth. Seedlings with intact seed reserves had higher mycorrhizal colonization than seedlings with partial or no seed reserves which clearly indicates that the seed reserves are not only important for seedling development but are also essential for mycorrhizal formation.