The present research was conducted to study the influence of organic and inorganic sources of nutrients as well as antioxidant on rice quality. The experiment was designed in split-split plots with four replications, where main plots were assigned to nitrogen (0, 55, 110 and 165 kg N ha−1) and sub plots were allocated to compost (0, 3.5 and 7 tons ha−1), while the sub-sub plots were assigned to ascobien (control, spraying with ascobien in two times at 15 and 30 days after transplanting (DAT), spraying with ascobien three times at 15, 30 and 45 DAT). The result indicated that grain quality traits were significantly influenced by the organic and inorganic fertilizers, and ascobien. The percentage of hulling, milling and amylose were positively and significantly influenced by nitrogen, organic and antioxidants application. Most of studied characters produced the highest values with the organic fertilize were combined with nitrogen and antioxidants. Application of 110 kg N ha−1, 7 t ha−1 compost and two or three spraying of ascobien, 110 kg N ha−1 or 3.5 t ha−1 compost and three times spraying and 55 kg N ha−1, 7 t ha−1 compost and two times spraying could be recommended for optimum grain quality of Sakha106 rice variety. It can be concluded that compost along with the foliar application of ascobien can be saved from 50 to110 kg N ha−1, without reducing grain quality. It can be the key to reduce the need for chemical fertilizers and decrease the cost of production with keeping healthy soil.

The obtained results showed that rice plants sown on the second date (May 10 th) surpassed those which sown on the late date of sowing (June 10 th) in plant height, leaf area index, dry matter accumulation (g m-2), tillers number m-2 , panicle number m-2 , number of filled grains panicle-1 , 1000-grain weight, straw yield and grain yield as well as aromatic level in both seasons. There was no significant difference between rice sown on the April 24 th or May 10 th in the most studied traits. Delay in sowing date significantly increased unfilled grains %, protein % and amylose content % in the two seasons. Aromatic rice varieties varied significantly in most measurements of growth, grain yield and yield attributes, in both seasons. Plants of the Egyptian Yasmin variety having the highest values in the most mentioned traits among the other tested varieties in the two seasons. Plants of Egyptian Yasmin in the two seasons and IR 77510 in the first season produced the greatest grain yield with high aroma level. Plants of IR 65610 variety produced the lowest grain yield in the two seasons. Concerning correlation coefficient among studied characters, grain yield had highly significant positive effect with 1000 grain weight and number of grains per panicle and significant positive with number of panicles m-2. It can be concluded that the optimum sowing date of Egyptian Yasmin variety is April 24 th and May 10 th while, sowing date of May 10 th is the one optimum for IR 77510, IR 78530 and IR 71137. Generally aromatic varieties i.e. Egyptian Yasmin, IR77510-88-1-3-3, IR78530-45-3-1-3, IR 74052-177-3-3, IR 71137-51-2 and IR65610-38-2-4-2-6-3 could be recommended to be sown in April 24 th and May 10 th .

A field experiment was conducted during the 2018 and 2019 rice growing seasons at The Experimental Farm of Rice Research and Training Center, Sakha, Kafrelsheikh, Egypt, to study the effect of foliar application of NPK (20:20:20) or urea combined with different nitrogen levels on grain yield and quality of Sakha 109 rice variety. Urea (46.5% N) and complex paste water-soluble NPK fertilizer (20:20:20) were used as the nutrient sources for the experimental treatments. For foliar application, NPK was used at the rate of 2 gm per liter of water and nitrogen used was at the concentration of 2% as urea. The field experiments were laid out in a Randomized Complete Block Design with four replications. The studied characteristics were chlorophyll content (SPAD value) at 55 days after transplanting, plant height at harvest, number of panicles per hill, panicle length, panicle weight, number of filled grains per panicle, unfilled grains percentage, 1000-grain weight, grain yield, straw yield and grain quality characteristics (hulling, milling and head rice percentages). N and K uptake (kg ha -1 ) were also determined. All studied characteristics were significantly influenced by the foliar fertilizer application in the two seasons. Application of NPK or N alone twice might improve rice grain yield and quality. The economic feasibility indicated that the application of 123.75 kg N ha -1 combined with foliar application of NPK or 2% nitrogen twice recorded the highest values of gross return and net return as well as a benefit-cost ratio.

The present study was carried out at the Experimental Farm of Agricultural Research Station, Sakha, Kafr El-Sheikh, Egypt over 2018 and 2019 rice growing seasons. This investigation aimed to study the effect of potassium sulphate foliar application on the productivity and grain quality characteristics of rice (Sakha 109 variety). The potassium sulphate was applied at the concentration of 1% K2SO4 at various growth stages. The examined treatments were; K1: Control (distilled water spray), K2: spray at 20 day after transplanting (DAT), K3: spray at 35 DAT, K4: spray at 50 DAT, K5: spray at 20 and 35 DAT, K6: spray at 20 and 50 DAT, K7: spray at 35 and 50 DAT, K8: spray at 20, 35 and 50 DAT. The experiment was planned in a Randomized Complete Block Design with four replications. At harvest, the studied characteristics were plant height, number of panicles per hill, panicle length, panicle weight, number of filled grains per panicle, unfilled grains percentage,1000-grain weight and total yield of both grain and straw per hectare. The grain quality characteristics (Hulling, milling, head rice, nitrogen content and potassium content) were measured at different storage periods (0, 3, 6 and 9 months after harvest). The results showed that all studied traits were significantly affected by potassium treatments. Potassium application improved the grain quality characteristics at different storage periods. Foliar application of potassium three times at different growth stages (K8) surpassed other treatments in terms of yield quantity and quality.

A field experiment was carried out to investigate the effect of organic and inorganic fertilizers and their combinations under different irrigation intervals on yield and its attributes of the Giza178 rice cultivar, as well as, the availability of some micronutrients in the soil. Irrigation treatments were continuous flooding (CF), continuous saturation (CS), irrigation every 6 days (E6D), every 9 days (E9D) and every 12 days (E12D), while the fertilizer treatments were control (without fertilizer), 5t cattle manure ha -1 (CM), 5t compost ha -1 (C), 5t cattle manure +110 kg N ha -1 (CM+110N), 5t compost +110 kg N ha -1 (C+110N) and the recommended N rate of 165 kg N ha -1 (165N). Prolonged irrigation intervals of more than 6 days substantially decreased the yield and its attributes, Fe and Mn concentration in the soil in both seasons. The opposite was true for Zn concentration. Fertilizer sources containing chemical N (165N) alone or 110N with C or CM significantly surpassed each of the two organic sources alone in yield and yield attributes in the two seasons. The application of C+110N fertilizer with irrigation E6D was statistically at par with the recommended interaction (CF irrigation X 165N fertilizer) in yield and its attributes. The total amount of irrigation water applied was decreased by prolonging the irrigation interval. The inverse was true for water saved and water productivity in kg grains m -3 . Application of C+110N fertilizer with irrigation E6D recorded the highest water productivity and saved water > 3000 m 3 in the two seasons.