تأثيرتراكيز ومراحل رش النتروجين في حاصل البذور ومكوناته لمحصول البرسيم

Abstract

ABSTRACT A Field study was carried out at experimental station of the coll. Of agric. Enge. Sci .University of Baghdad from Mid-October 2018 to Mid of July 2019.The main objective was to find out the effect of nitrogen concentration (0,1,2 and 3 g.L-1 ) and three foliar application stages ( Flower-bud emergence,10% Flowering and 25% Flowering) On seed yield and its components of Berseem ( Trifolium alexandrinum L.) local var. Layout of the experiment was a split plot in a ( R.C.B.D ) with three replications. Foliar application stages were Used as main-plot while nitrogen Conc. Were used as sub-plot. The characters studied were plant height no. of florets .raceme-1 , No. of seeds .raceme-1 , % of florets abortion, No. of racemes.m-2 .during full bloom , No.Of ripe racemes.m-2 . % of abscission racemes, 1000 seed weight , Biological yield , Seed yield and harvest index , The data obtained for each of the character was analyzed independently using the analysis of the variance method .Means were compared using ( L.S.D) test at 5% level. Results and conclusions from this experiment are summarized as follows: 1 – Foliar application of N at Concentrations of (2,3, g.L-1) resulted in a significant increment in mean plant height ,No. Of racemes.m-2 during full Bloom, No. of ripe racemes .m-2 and % of abscission racemes, but it reduce the % of florets abortion. 2 – Application of N at concentration 2 and 3 g.L-1 gave highest seed yield amounted to 467.5 and 473.5 Kg.ha-1 respectively, they also gave highest Biological yield amounted 3.285 t.ha-1 and 3.302 respectively. 3 – Foliar application of N at 10% of flowering stage was significantly increased No. of florets .raceme-1 , No. of seeds.receme-1 , No. of racemes .m-2 during full bloom, No. of ripe racemes and harvest index . 4 – Addition of N. at flower – bud emergence stage significantly increase plant height , % of florets abortion and % of racemes abscission . 5 – The highest seed yield was obtained when N sprayed at 10% flowering stage (481.9 Kg.ha-1 ) and it was significantly different compare with other stages , While foliar application of N at Flower – bud emergence stage gave highest biological yield 3.396 t.ha-1 and it was significantly different compare with other stages. 6 – There was significant interaction between N concentrations and the stages of foliar application on No. of seed .raceme-1 , % of florets abortion and No. of racemes.m-2 during full bloom and ripe stage. 7 – There were no significant effect of the two factors on 1000-seed weight and the conc. of N , on harvest index .