Cultivars Response of Flax (Linum usitatissimum L.) to Different Nitrogen Sources in Dry Environment

TWO YEARS field experiment were carried out at Demo experimental farm, Faculty of Agriculture, Fayoum University, Egypt in 2015/16 and 2016/17 seasons to examine the effect of nitrogen sources as soil application on straw and seed yields as well as seed quality of flax. A split-plot arrangement with three replications was used. Three cultivars of flax i.e., Sakha-1, Sakha-2 and Giza-9 occupied the main plots. While, N-sources, i.e., ammonium nitrate (23.5 %), urea (46.5%) and ammonium sulfate (20.6%) distributed in the sub-plot. The obtained results clarified that Sakha-1 gave the highest straw yield and its attributes mean values i.e., plant height, technical stem length and straw yield plant^-1. While, Sakha-2 gave the highest mean values for number of branches plant^-1 and stem diameter. In addition, Sakha-2 cultivar was exceeded the other two cultivars with regard to seed yield and related traits i.e., fruiting zone length, no. of fruiting branches plant^-1, No. of capsules plant^-1, 1000-seed weight and seed and oil yield fed^-1. Ammonium nitrate followed by ammonium sulfate as N-sources gave the highest straw and seed yields and its related traits when compared with urea. Thus, the recommendations of this study are cultivating Sakha-2 variety and fertilized by ammonium nitrate as N-sources. The obtained results of regression analysis of seed yield indicated that, there are two traits i.e. seed yield plant^-1 and No. of capsules plant^-1 in the first season and Zn mg 100g^-1 in the second one, were significantly (P≤ 0.001) contributed to variation in seed yield feddan.