كليدواژه :
عملكرد دانه , بيوماس , كلزاي پاييز , تراكم بوته , كود نيتروژن
چكيده لاتين :
To study the effects of planting density and urea (46% N) application rate on yield and some morphological traits of winter colza (cv. Zarfam, an inbred variety from Regent x Cobra) a factorial experiment in the framework of a complete block design with 4 replications was conducted in Seed and Plant Improvement Institute, Karaj-Iran in 2002. The treatments were comprised of four levels of planting density and N application rates viz. 150,190, 230 and 270 plants m"2 and zero, 100, 200 and 300 kg urea ha"1. Analysis of variance revealed that different levels of density and N fertilizer significantly affected dry matter accumulation (biomass) at the three stages of plant growth (rosette, stem elongation, and 50% flowering). Increasing planting density and N application rate also significantly affected total biological yield, seed yield, Harvest Index (HI), pod bearing stem length, pod number in main and sub-branches, total pod number plant"1 as well as 1000 seed weight. Increasing N fertilizer exerted progressive effects on all traits, but planting density decreased pod bearing stem length, pod number in main and sub-branches and total pod number plant"1. The highest biomass, HI and 1000 seed weight were obtained from 190 plant m"2 treatment. Increase in planting density as well as in N application rate increased plant height, but did not significantly affect the oil seed percentage. Finally, the planting density of 190 plants m" (equal to seed rate of 8 kg ha"1) along with application of 200 kg of urea ha"1 formated the optimum combination for which the highest seed yield (3122 kg ha"1) had been observed.
