ANBAR JOURNAL OF AGRICULTURAL SCIENCES

Abstract

A field trail was conducted at the Field Crop Station of IPA Center for Agricultural Research, Baghdad, Iraq during 2001-2002 and 2002-2003 seasons to determine the effect of sowing dates, levels of Nitrogen, spacing between plants and the interaction between them on seed yield and yield components of rapeseed. Rapeseed was sown in four sowing dates (5, 25 Oct., 14 Nov., 4 Dec.). Each date was sown in a separated experiment. A split plot arrangement in randomized complete block design with four replicates was used for each date. Nitrogen levels (100, 200, 300) kg N/ha., were assigned in the main plots, where as the spacing between plants (4, 8, 12) cm were assigned in the sub-plots.
The results showed that the first planting date (5 Oct.) gave the highest seed yield (2.7, 2.3 t/ha.) in the first and second seasons, respectively, and the highest oil yield (0.979 t/ha) in the second season. The level 300 kg N/ha gave the highest seed yield (2.5, 2.2 t/ha) in the first and second seasons, respectively, and the highest oil yield (0.904 t/ha) in the second season. The intra-spacing (4 cm) gave the highest seed yield (2.5, 2.1 t/ha) in the first and second seasons, respectively. And the highest oil yield (0.903 t/ha) in the second season.
The interaction between first planting date (5 Oct.) and 300 kg N/ha gave the highest seed yield (3.4, 3.0 t/ha) for first and second seasons respectively and the highest oil yield (1.3 t/ha) for the second season. The interaction between first planting date (5 Oct.) and intra spacing (4 cm) gave the highest seed yield (3.3, 2.7 t/ha) for first and second season, respectively and the highest oil yield (1.2 t/ha) in the second season. The interaction between the first planting date (5 Oct.) and 300 kg N/ha with intra-spacing (4 cm) gave the highest seed yield and oil yield ( 3.4, 1.5 t/ha) respectively in the second season. Results showed that maximum seed yield and oil yield could be achieved by sowing rapeseed var. Cam-c in central Iraq at 5th of October and 300 kg N/ha. with intra-spacing (4 cm) which gave the highest seed yield (3.4 t/ha) and the highest oil yield (1.5 t/ha) in the second season.