Material and method
Three varieties of waxy corn, which were Chainat waxy corn 84-1, Fancy 111 Purple waxy corn and Boukgeen4 were studied on the effect of chitosan liquid fertilizer with ammonium sulfate (21-0-0) and control (ammonium sulfate; 21-0-0) on growth. The experimental design was randomized complete block design (RCBD) with three replications. Waxy corn seeds were sowed directly in the field with spacing of 30 × 30 cm. Chitosan liquid fertilizer was sprayed to seedling at 15 days old after seeds germination and every weeks. A dilution, 1: 1000 of chitosan liquid fertilizer was sprayed to plant every weeks.
The improvement of waxy corn used self-pollination and cross-pollination. Preparation of female inflorescences by using paper bags covered stigma male and female inflorescences before pollination. Breeding used hand pollination and repeated pollination for 5 day. Ears were harvested when the silk turned to brown.
Data were collected percent of germination, plant height and leaf length, which recorded every week, ear weight, total dried seed weight, dried seed weight of 100 seeds.