Two pot experiments were carried out at the greenhouse of the Cotton Research Institute, Agric. Res. Cent., Giza, Egypt during 2015 and 2016 seasons to study the response of cotton plant to application of some nutrients to improve the performance of cotton plant under irrigation of saline water to increase growth, yield and yield components and fiber quality of Giza 90 cotton cultivar. The experimental design was a split plot design with four replications. Main plots included saline water solutions treatments (control, 2000, 4000, 6000 and 8000 ppm), sub plot included four nutrients application (Potassium Humate, Algex, Poly Ethylene Glycol (PEG) 6000 and Potassein compared with control). The obtained results could be summarized as follows: Irrigation with saline water over seasons significantly decreased plant height, number of fruiting branches/plant, number of open bolls /plant, boll weight, seed index, seed cotton yield per plant, fiber length, uniformity index, fiber strength and micronaire value, while, lint % was significantly increased. Nutrients application had significant effect on growth parameters, yield and its components and fiber properties under study, All nutrients treatments gave the highest values of growth parameters, yield and its components and fiber properties as compared with the control in both seasons. In general, plants sprayed with PEG gave the highest averages of plant height, number of fruiting branches/plant. Potassium Humate gave the highest averages of yield and its components and fiber properties followed by plants sprayed with Algex, while the plants sprayed with PEG as came the last in these respect in both seasons. Interaction between irrigation with slain water and nutrients application by salinity tolerance inducers had a significant effect on plant height, number of fruiting branches per plant, boll weight, number of open bolls /plant, seed index, seed cotton yield /plant and fiber quality under study in both seasons. Plants treated with foliar nutrients under salinity condation scored the highest average of growth parameters, yield and its components and fiber properties. Potassium Humate, Algex, PEG and Potassein applications to plants under normal and salinity conditions had positive effects on improving the performance of cotton plants, which increased plant growth and yield especially under salinity conditions.

Egyptian Journal of Botany http://ejbo.journals.ekb.eg/ 2041 C OTTON is known as the king of fibers and an important source of oil. The aim of this study was to evaluate the mitigating effects of three osmoprotectants, including glycine betaine (GB), proline, and chitosan each at two concentrations of 400 and 200 parts per million (ppm), 100 and 50 ppm, and 300 and 100 ppm, respectively, on water deficit stress after irrigation intervals of 10-, 15-, and 20-days, relative to the untreated (control) plants. Data indicated that prolonged irrigation interval significantly decreased growth, yield, yield components, fiber parameters, total chlorophyll, Chl. a, and Chl. b, while, proline and total soluble sugars significant increased. All drought tolerance inducers showed significant increases in cotton growth and productivity traits. Generally, GB treated plants at 400 ppm showed superior traits of all studied parameters. For example, the interaction between irrigation intervals and GB application caused significant effects on growth and productivity as well as fiber quality and chemical properties. The application of drought tolerance inducers mitigated the effects of prolonged irrigation intervals in cotton, and all drought tolerance inducers achieved higher yield and yield component values at 15 days irrigation interval compared with the control at 10 days irrigation interval. Application of 400 ppm GB could improve cotton plants endurance against the negative effect of prolonged water intervals.