EFFECT OF IRRIGATION AND NITROGEN LEVELS ON THE QUALITY AND OIL YIELDOF BRASSICA SPECIES

A field experiment was conducted during the winter (rabi) seasons of 1 988-89 and 1989-90 st Hisar to study the effect of irrigation and nitr ogen levels on quality and oil yield of Brassica spp. Oil content vari ed significantly amongst Brassica species. Oilseed rape (Brassica napu s L.) had highest mean oil content (41.85%), followed by Indian mustar d [Brassica juncea (L.) Czernj. and Cosson] (40.32%) and Ethiopian mus tard [Brassica carinata (L.) Braun] (37.80%). B. juncea, B. napus and B. carinata gave oil yield 6.14, 5.17 and 6.01 q/ha respectively. Howe ver, quality parameters like protein, sinigrin glucosinolate content a nd iodine value were maximum in B. carinata, followed by B. juncea and B. napus. Irrigation had no effect on oil content and quality paramet ers, however. 2 and 1 post-sowing irrigations resulted in oil yield of 6.33 and 6.03 q/ha respectively. which were significantly higher than that under no post-sowing irrigation. The oil content of seed decreas ed significantly with an increase in level of N up to 120 kg N/ha, and the oil yield increased up to 80 kg N/ha, and sinigrin glucosinolate content and iodine value up to 20 kg N/ha during both the years.