Effect of Nitrogen Fertigation on First-year Pecan Seedling Growth

Abstract

Pecan (Carya illinoinensis) seedling rootstocks require several years of growth in the nursery before they are large enough to graft. In this experiment, first-year pecan seedlings were fertigated with varying amounts of calcium nitrate in an attempt to stimulate growth rates. Pecan seedlings were fertigated every 2 weeks from May through October for a total of 10 applications. Total amounts of nitrogen (N) applied by fertigation were 0, 4, 10, 20, and 40 g of N per seedling. Leaf samples were taken after the fourth and tenth fertigations, and leaf elemental concentration was affected by fertigation rates. Seedling height and caliper were measured monthly. Seedling caliper continued to increase throughout the experiment, whereas height increase stopped in September. Seedling height and caliper were unaffected by N fertigation except for the N rate of 40 g, which suppressed seedling growth. These results suggest that the N needs of the seedlings were met by a preplant application of 50 lb/acre N applied as 10N–4.4P–8.3K.