This experiment was conducted in summer seasons of 2016 and 2017 on tomato plants "6112" hybrid to evaluate tomato plants performance (vegetative growth characteristics and chemical constituents of leaves) in response to irrigation water treatments (magnetized and non-magnetized), foliar applications (chitosan, lithovit, selenium and yeast extract) and their interactions. Results indicated that the highest values of vegetative growth characteristics, i.e., plant height, number of branches, number of leaves, leaf area, fresh and dry weights as well as chemical constituents of leaves as photosynthetic pigments (Chl. a, Chl. b, total Chl. a+b and carotenoids) and leaf minerals content (N, P, K, Ca, Mg, Zn, Mn) were recorded when plants irrigated with magnetized water as compared with plants irrigated with untreated water in both studying seasons. On the other hand, Fe content responded negatively to irrigation with magnetized water.Comparing the effect of foliar applications, all foliar application treatments significantly enhanced vegetative growth parameters, leaf minerals and pigments contents compared to the check treatment. Foliar application of chitosan at 250 ppm is the superior in its effect on all the aforementioned characteristics followed by yeast extract at 10 g/L then lithovit at 1.5 g/L in the two seasons except for Fe content. The best results of both vegetative growth attributes and chemical constituents of leaves were recorded when plants irrigated with magnetized water and sprayed with chitosan at 250 ppm in both seasons. Thus, this treatment could be recommended to improve tomato plants performance under similar conditions of this study.

This investigation was conducted in the two successive summer seasons of 2010 and 2011 on sweet pepper plants "Madir" hybride at a private farm at Sahragt El-Soghra near Mansoura, Dakahlia Governorate, Egypt to study the effect of two sources of organic fertilizers (chicken manure and compost), biofertilizers (a mixture of Azotobacter chroococcum and Bacillus circulans bacteria and Mycorrhiza fungi), some foliar application treatments (seaweed extract, yeast extract and humic acid) and their interaction on vegetative characteristics and chemical constituents of leaves. Results indicated that the highest values of vegetative parameters, i.e., plant height, number of leaves, number of branches, leaf area, fresh and dry weights as well as chemical constituents of leaves, i.e., chlorophylls (Chl. a, Chl. b and total Chl. a+b), N, P and K percentages were recorded when plants supplied with chicken manure at 2.43 ton/fed. as compared with compost in the two seasons. Plants in the presence of biofertilizers recorded better growth performance and higher values of chemical composition in leaves than untreated plants in the two seasons. Comparing the effect of foliar applications, seaweed extract at 2.5 ml/L or yeast extract at 5 g/L recorded the highest significant values of most formentioned parameters compared with the control in both seasons. in addition, spraying humic acid at 1.5 ml/L came in the second order and significantly increased number of branches, fresh and dry weights in both seasons and leaf area in the second season as compared with the check treatment. The best results of both vegetative parameters and chemical constituents were recorded when plants fertilized with chicken manure at 2.43 ton/fed. and sprayed with either seaweed extract at 2.5 ml/L or yeast extract at 5 g/L in the presence of biofertilizers in both seasons. Therefore, this treatment could be recommended for improving sweet pepper performance under similar conditions of this study.

Two investigations were carried out in the open field to study the effects of some soil stimulating supplements, i.e., humic and fulvic acids, zeolite, chicken manure as well as compost on vegetative growth, chemical contents and productivity of sweet pepper plants under drip irrigation system. Results indicated that all applied soil substances significantly enhanced vegetative growth parameters, chemical constituents, endogenous phyto-hormones of leaves, yield and fruit quality compared to the control in both growing seasons of study. Soil applications of either zeolite or compost are the best treatments in enhancing most of the aforementioned parameters. Additionally, our results undoubtedly confirm that the application of zeolite or compost could decrease chemical fertilizers through improving the efficiency of both fertilizers and irrigation water which in turn increase vegetable crops production, minimize economic costs as well as limit environmental contamination.

Optimal calcium nutation of yellow pepper plants is considered one of the most significant factor for best growth, development and yield as well as fruits quality. So, foliar fertilizations have been applied with large in horticultural production especially vegetable crops. Calcium is one of vital nutrients all over plant life cycle. The aim of this research was to compare and evaluate the effects of different Ca fertilizers (sources) on productivity of yellow pepper hybrid VZ 461 grown under open filed conditions. Ca was applied in the following forms chelated, chloride, nitrate, sulphate, superphosphate and complex with boron. All calcium sources have positive effects on growth, biochemical content, photosynthetic pigments, yield and fruits quality compared with the control. Also, all Ca treatments caused a few numbers of fruits with blossom end root (BER) symptoms percentage compared with control fruits. The superior one was Ca chelated in most cases and followed by calcium nitrate and complex with boron in both seasons of study.

Snap bean have been cultivated in winter season for succulent green pods with reduced fiber and highly minerals and carbohydrates content for either exportation or local markets. The immature pods are consumed as green vegetables. It responds much better to foliar fertilizers application specially potassium (K).In this concern, two experiments were conducted to study the effect of K fertilizers sources on yield and pods quality of snap bean under clay loam soil conditions. The experiment consisted of nine sources of K fertilizers arranged in randomized complete block design with three replications. There were significant differences among most K sources in their effects on most studied parameters. The results showed that, potassium phosphite recorded the best vegetative and chemical parameters followed by potassium silicate (without significate differences between them in most cases). Also, maximum early and total green pod yield were obtained from potassium phosphite foliar application. On the other hand, maximum marketable pod yield was recorded from the application of potassium silicate. Since, the experiment was conducted in a single location and two seasons, so repeating the experiment for more locations (different soils) and other new K fertilizers could be help in drawing sound conclusive recommendations to the applied production and achieving excellent pods quality for local marketing, exportation and storage.