Effect of sowing dates and seed rates on some rice cultivars

Abstract

Two field experiment were conducted at Rice Research and Training Center (RRTC) – Sakha, kafr- El sheikh, governorate, Egypt in 2006 and 2007 seasons., to study the effect of seed rates under different of sowing dates (20th April, 1st May and 10th May) on some rice varieties. Three rice varieties Sakha 101, Sakha 103, Sakha 104 were tested. Three seed rates were used (48, 95 and 144 kg /ha). Nitrogen fertilizer was added as urea form 46.5% N in two splits, 2/3 was applied as mixed in dry soil before flooding irrigation water and 1/3 was added at panicle initiation. Under three different sowing dates 20th April, 1st May and 10th May with seedling age were transplanted 25 days from sowing by 20×20 cm planting spacing. All agricultural practices were added as recommended for each cultivar. The study was arranged as split- split plot design and with four replications; three sowing dates were allocated in the main plots; seeding rates were allocated in sup-plots and three rice varieties were allocated in the sup-sup plots. The results found that maximum tillering, panicle initiation, heading dates, leaf area index, chlorophyll content, 1000-grain weight, panicles length, number of panicles per hill and grain yield (Ton/ha-1) were increase by increased seed rates up to 143 kg seed ha-1. Earlier sowing time (20th April) date of sowing gave had the highest value of all studied characters in Sakha 101 variety and this rice variety surpassed other varieties to all attributes under study. While 30th May date of sowing with Sakha 103 inbred rice gave the lowest value of all traits under study