The response of the antioxidant system to salt stress was studied in the roots of the cultivated tomato Lycopersicon esculentum Mill. cv. M82 (Lem) and its wild salt-tolerant relative L. pennellii (Corr.) D'Arcy accession Atico (Lpa). Roots of control and salt (100 mM NaCl)-stressed plants were sampled at various times after commencement of salinization. A gradual increase in the membrane lipid peroxidation in salt-stressed root of Lem was accompanied with decreased activities of the antioxidant enzymes: superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6), ascorbate peroxidase (APX; EC 1.11.1.11) and decreased contents of the antioxidants ascorbate and glutathione and their redox states. In contrast, increased activities of the SOD, CAT, APX, monodehydroascorbate reductase (MDHAR; EC 1.6.5.4), and increased contents of the reduced forms of ascorbate and glutathione and their redox states were found in salt-stressed roots of Lpa, in which the level of membrane lipid peroxidation remained unchanged. It seems that the better protection of Lpa roots from salt-induced oxidative damage results, at least partially, from the increased activity of their antioxidative system.

The transition from reversible to permanent wilting, in whole tomato seedlings (Lycopersicon esculentum Mill. cv. M82) following severe salt-stress by root exposure to 300 mM NaCl, was investigated. Salinized seedlings wilted rapidly but recovered if returned to non-saline nutrient solution within 6 h. However, after 9 h of salt-treatment 100% of the seedlings remained wilted and died. Remarkably, the addition of an anti-oxidant (0.5 mM ascorbic acid) to the root medium, prior to and during salt-treatment for 9 h, facilitated the subsequent recovery and long-term survival of c. 50% of the wilted seedlings. Other organic solutes without known anti-oxidant activity were not effective. Salt-stress increased the accumulation in roots, stems and leaves, of lipid peroxidation products produced by interactions with damaging active oxygen species. Additional ascorbic acid partially inhibited this response but did not significantly reduce sodium uptake or plasma membrane leakiness.

The possible involvement of the antioxidative system in the tolerance to salt stress was studied in the cultivated tomato Lycopersicon esculentum Mill. cv. M82 (M82) and its wild salt‐tolerant relative L. pennellii (Corn) D'Arcy accession Atico (Lpa). All analyses, except that of monodehydroascorbate reductase (MDHAR), were performed of the youngest fully‐expanded leaf of control and salt (100 mM NaCl) stressed plants, 4, 7, 10, 14, 18 and 22 days after completing the stress treatment. In Lpa, constitutive level of lipid peroxidation and activities of catalase (CAT) and glutathione reductase (GR) were lower while the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and dehydroascorbate reductase (DHAR) were inherently higher than in M82. Relative to M82, lipid peroxidation was much lower and the activities of SOD, CAT and APX were higher in Lpa at 100 mM NaCl. The activity of DHAR decreased more in Lpa than in M82 under salt stress, and the activity of MDHAR, which was lower in Lpa than in M82 under control conditions, increased much more and to a higher level in salt‐treated Lpa plants. GR activity decreased similarly in the two species under salt stress. The results of these analyses suggest that the wild salt‐tolerant Lpa plants are better protected against active oxygen species (AOS), inherently and under salt stress, than the relatively sensitive plants of the cultivated species.

Two field experiments were carried out at the Horticulture experimental station of Ministry of Agricultural at El-Baramon experimental farm, Dakahlia Government, Egypt., during the two successive summer seasons of 2011 and 2012 to investigate the effect of irrigation intervals, foliar application of different antitranspirants under compost rates as well as their interactions on growth and productivity of eggplant (Solanum melongena L.).Twenty four treatments were arranged in split-split plots design, which were the simple possible combination between three rates of organic manure (0, 50 and 100% from recommended doses), two treatments of irrigation intervals (10 and 20 days) and four treatments of foliar application from antitranspirants (control, kaoline, CaCO3 and dyroton). Each treatment was replicated three times. The most important findings could be summarized as follows:Increasing compost from 0 to 4 ton/fed. significantly increased vegetative growth of eggplant, yield and its components, fruit quality and its chemical composition N, P, K%, Fe ppm, TSS% and VC(mg/100g) . Short irrigation intervals (10days) significantly increased all parameters under investigation. The spraying with dyroton at 3% led to significant increase in growth characters traits, N,P,K%, Fe ppm, TSS%, VC, firmness, fruit quality and yield as well as its components.The interaction between organic manure and irrigation intervals significantly affected growth parameters, yield, fruit quality and its chemical composition except stem diameter in the 2 nd season, N%, TSS% in the 1 st season, K% and average fruit weight during both seasons.Interaction effect of organic manure and antitranspirants significantly affected growth parameters, yield, fruit quality and its chemical composition except K% and stem diameter in the 2 nd season; VC and average fruit weight during both seasons.Interaction effect between irrigation intervals and antitranspirants characters under investigation had significant effect on all studied treats except TSS% in the 1 st season, stem diameter in 2 nd K, VC and average fruit weight during both seasons.The interaction effect between organic manure, irrigation intervals and antitranspirants significantly affected to growth parameters, yield, fruit quality and its chemical composition except average fruit weight during both seasons.

Two field experiments were conducted at the private field in El-Zarka City, Damietta Governorate, Egypt, during 2016 and 2017 seasons to evaluate the effects of organic fertilization rates (compost rates) and foliar spraying by some biostimulant substances on yield and its components,growth as well as quality of snap bean (Contender cultivar). A split-plot with three replicates was the experimental design. The vertical-plots to three compost rates i.e. without compost (control treatment), 50 % of the recommended dose (2 tons compost/fed) and 100 % of the recommended dose (4 tons compost/fed).The horizontal plots were devoted to four treatments of foliar spraying with some biostimulant substances i.e. foliar spraying with brassinolid at the rate of 10 ppm, moringa extract at the rate of 200 ppm, chitosan at the rate of 200 ppm and tap water (control treatment). The most important results can be summarized as follows: The highest values of vegetative growth characters, pod yield and its components as well as quality of snap bean pods were resulted from fertilizing with (4 tons compost/fed) 100 % .On the contrary, the lowest values of growth characters, pod yield and its components and chemical composition of snap bean pods were obtained from plants not treated with compost (control treatment). Foliar spraying snap bean plants three times with 200 ppm chitosan exceeded all foliar spraying with some biostimulant substances and resulted the highest values of vegetative growth characters, pod yield and its components as well as quality of snap bean pods. Followed by foliar spraying with brassinolid at the rate of 10 ppm and then moringa extract at the rate of 200 ppm. Whereas, the lowest values of vegetative growth characters, pod yield and its components as well as quality of snap bean pods were resulted with control treatment (spraying with tap water).It can be concluded that organic fertilizing with 4 tons compost/fed and foliar spraying three times with chitosan at the rate of 200 ppm folloued by spraying with brassinolid 10 ppm in order to obtain high yield and its components,growth as well as quality of snap bean (Contender cultivar).