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Improving Productivity and increasing farmer income through reducing the production inputs is the main challenge for rice grower. A field experiment was conducted at the Experimental Farm of Sakha Agricultural Research Station, Kafr El-Sheikh, Egypt in order to evaluate the effects of foliar application of NPK at different growth stages on productivity and nutrients uptake by rice variety Sakha108 under transplanting condition during the summer season of the years 2017 and 2018. Urea (46.5% N), super phosphate (15% P 2 O 5), potassium sulphate (50% K 2 O) and complex water soluble fertilizer NPK (28:28:28) were used as the nutrient sources for the experimental treatments. The treatments were as follow: T1 = Recommended urea, super phosphate, potassium sulphate (control), T2 = 2/3 NPK urea, super phosphate, potassium sulphate as basal +

Phosphorus is a macronutrient that plays number of important roles in plants. It is a component of nucleic acids, so it plays a vital role in plant reproduction, of which grain production in an important result. Intensive cropping system, high phosphorus consumer crops, high yielding rice varieties and high soil pH restricted P availability resulted in low rice yield. The experiment was carried out at farm of Sakha Agriculture Research Station, Kafrelsheikh during 2014 and 2015 summer seasons, in clayed alkaline soil, the study aimed to find out the effect of different levels of phosphorus fertilizer on yield and yield attributes of rice in low soil phosphorus. The treatments consist of four cultivars; Egyptian hybrid rice one (EHR1), Sakha102, Sakha106 and Giza179 and five phosphorus (P) fertilizer levels Viz. 0, 12, 24, 36 and 48 kg P 2 O 5 . ha -1 as single super phosphate (15.5 % P 2 O 5 ). Split plot experiment design with four replications was used. At heading some growth parameters were measured yield and yield attributes were estimated. Nitrogen and phosphorus uptake were determined.The studied varieties were certainly differed regarding their yield and yield attributes as well as nitrogen and phosphorus uptake. The Egyptian hybrid rice one (EHR1) apparently surpassed others studied varieties in growth, grain yield and most of yield components characteristics.All the studied parameters of rice varieties differed significantly with the application of phosphorus fertilizer. Plants grown without added phosphorus gave the lowest grain yield. The higher phosphorus levels exhibited higher grain yield. A significant interaction between varieties and phosphorus levels in respect of yield and yield attributes of rice were observed. The highest grain yield was recorded with Egyptian hybrid rice one at 48 kg P 2 O 5 . ha -1 .It could be concluded that high yielding rice varieties, EHR1 and Giza 179 responded to phosphorus fertilizer up to 48 kg P 2 O 5 /ha -1 . Furthermore, the medium yielding varieties; Sakha102 and Sakha106 performed better with P level of 36 kg P 2 O 5 /ha -1 . The application of phosphorus for rice after heavy phosphorus consumer crop and high pH soil is imperative to fetch high rice grain yield.

Two field experiments were conducted under saline soil during 2013 and 2014 seasons at Research Farm of El Sirw Agricultural Research Station, Damietta province, Egypt. Improving salinity tolerance and grain yield of hybrid rice were the main objectives of the current study. The experimental soil was clayey with salinity levels of 7.70 and 7.30 dS/m in 2013 and 2014 seasons, respectively. Egyptian hybrid rice one (EHR1) variety was used in this study. The studied treatments were including; water (spray control treatment), GA 3 with concentration (5, 10, 15 ppm), Auxin with concentration (5, 10, 15 ppm), Cytokinin with concentration (5, 10, 15 ppm). Those substances were sprayed at mid tillering, panicle initiation and booing stage. At heading the growth parameters of EHR1 was measured at heading stage as well as plant chemical contents were estimated. Grain yield and its components were estimated at harvest. The factorial design was used in the experiment with three replications. The obtained results showed that foliar spray treatments were found to be increased effective in enhancing growth plants of EHR1 and increased nutrient leaf content such as N and K. therefore, the salinity withstanding of EHR1 was raised resulted in proper growth and reasonable grain yield under salt stress. Applying Cytokinin or Auxin at 10 ppm as foliar application was most effective treatment in improving rice productivity under salt affective soils.

One of the main problems of lowland rice cultivation and production is the shortage of irrigation water, which effects the vegetative growth rate and the amount of yield and its component. In this study, afield experiment was conducted to find out the impact of some plant growth regulating substance on rice cultivars namely; Giza179 cultivar and Giza177 cultivar grown under different irrigation intervals in 2015 and 2016 growing season sat the farm of Agricultural Research Station, Sakha, Kafrelsheikh, Egypt. The Experiment was conducted using Randomized Complete Block Design with Strip-split plot arrangements. Main plots consisted of the three irrigation intervals namely; irrigation every 4 days (I1), irrigation every 8 days (I2) and irrigation every 12 days (I3), while sub plots devoted torice cultivars while the sub-sub plots contained the four levels of plant growth regulators: T1: spraying by cytokinein with concentration of 20 ppm, T2: spraying by abscisic acid with concentration of 15 ppm (ABA), T3: spraying by proline with concentration of 80ppm, T4: control (without any spray).The recorded data were chlorophyll content (SPAD), plant height (cm) at harvest, number of panicle (m-2), panicle weight (g), number of filled grains/panicle, number of unfilled grains/panicle, 1000-grain weight (g), grain yield (t/ha) and straw yield (t/ha). The main results indicated that irrigation every 4 and 8-days intervals cause an increase in all the previous studied characters, while irrigation every 12 days significantly reduced it. Spraying the tested rice cultivars by three growth regulators increased all studied characters as compared with control treatment. spraying Giza 179 cultivar with Cytokinin under the different irrigation intervals surpassed Giza177 cultivar and gave the highest value in all the studied characters expect 1000-grain weight followed by ABA. Spraying the two tested cultivars by Cytokinin under irrigation every 12 days which cause water stress relief the harmful of stress in the plant and increase the yield by about 3.2 t/ha specially with Giza179 cultivar as compared with control (without any growth regulator). Moreover, the application of cytokinein extend irrigation intervals from irrigation every 4 days up to irrigation every 8 days without any significant reduction in the yield. these results are benefit for farmers which safer from shortage of irrigation water in their rice field.