Possibility of Using Compost as A Partial Substitute for Mineral Nitrogen Fertilizer and Evaluating This on Performance of Sugar Beet Plants Sprayed with Boron from Different Sources. امکانية استخدام سماد المکمورة کبديل جزئي للسماد النيتروجيني المعدني وتقييم ذلک على اداء نباتات بنجر السکر المعاملة رشا بمصادر بورون مختلفة.

Two field experiments were conducted at Dakahlia., Egypt  during 209/2020 and 2020/2021 seasons to evaluate the response of sugar beet to boron spraying (Control, 1.0 mg B as Milano [15 %boron]/15 L water,  2.0 mg B as Milano 15 %boron/15 L water, 0.5 g B as borax 11%boron /15 L water, 1.0 g B as borax 11%boron /15 L water, 0.5 g B as boric acid 17%boron/15 L water and 1 g B as boric acid 17%boron /15 L water ) and combinations of compost with mineral nitrogen fertilizer (100%  N mineral nitrogen, 75 mineral N + 25 % compost, 50 mineral N + 50 % compost, 25 mineral N + 75 % compost and100% N as compost.). Split plot design in 3 replications was used where, the N sources were attributed at the main plots while, the sub plots included boron treatments. The results showed that 100% N mineral nitrogen was superior treatment compared with the other N treatments, as well as spraying B at rate of 1.0 g 15 L-1 as boric acid came in the first order compared with the other B treatments. On the other hand, the plants received 75 mineral N + 25 % compost and sprayed by Boron from any source and by any rate recorded the better responses compared with plants received 100% N mineral nitrogen as mineral fertilizer without B application.