BSTRACTTwo greenhouse experiments were carried out at Army Farm, at El-Amria region, Alexandria, Egypt, during the two seasons of 2016-2017 and 2017-2018, as an attempt to rationalize of irrigation water through studying the effect of three water regimes, three pruning systems and four potassium silicate rates on the dry mass accumulation in the various plant organs of sweet pepper. Results showed that application of the lower amount of irrigation water (30% depletion ratio) with repeat its addition achieved the highest significant mean values of roots, stems, leaves and whole plant dry mass at one, three and nine months after transplanting (MAT), as well as fruits dry mass after three and nine MFT, in the two seasons. Furthermore, the results indicated that un-pruned sweet pepper plants achieved significant higher mean values of roots, stems and whole plant dry mass, at three and nine MAT, in both seasons, as well as fruits dry mass at nine MAT only , in both seasons. The addition of, foliar application of potassium silicate up to 500 or 1000 mg l -1 , significantly, accumulated higher dry weight in roots, branches, leaves, fruits and whole plant of sweet pepper plants after one, three and nine MAT, compared with that unsprayed, in the two seasons. Likewise, sweet pepper plants that un-pruned or pruned up to 3 branches plant -1 and irrigated with the lower amount of irrigation water (30% depletion ratio) achieved the highest values of the dry mass of branches, leaves, fruits and whole plant at one, three and nine MAT compared with that pruned on two branches plant-1. However, the highest dry mass value of roots, branches, leaves, fruits and whole plant of pepper were obtained from the treatment combination included the lower amount of water (30 % water depletion ratio) and spray 1000 mg l -1 of potassium silicate, in both seasons, after one, three and nine MAT. Interactions between pruning systems and potassium silicate concentrations indicated that the highest values of the dry mass of roots, branches and whole plant of sweet pepper plants were achieved from treatment combinations containing un-pruned plants and sprayed the plants with 1000 mg l -1 of potassium silicate, in both seasons.

Strawberry is a non-climacteric fruit but exhibits a limited postharvest life due to rapid softening and decay. A strawberry coating that is natural and safe for human consumption can be used to improve the appearance and safeguard the fruits. In this study, 20% and 40% Aloe vera gel alone or in combination with 1% lemongrass essential oil (EO) was used as an edible coating for strawberries. After application of all the treatments, the strawberry fruits were stored at a temperature of 5 ± 1 °C at a relative humidity (RH) of 90%–95% for up to 16 days and all the parameters were analyzed and compared to control (uncoated fruits). The results show that A. vera gel alone or with lemongrass EO reduced the deterioration and increased the shelf life of the fruit. Treatment with A. vera gel and lemongrass EO decreased acidity and total anthocyanins and maintained fruit firmness. Treatment with A. vera gel 40% + lemongrass EO 1% led to the lowest weight loss, retained firmness and acidity, but increased the total soluble solids and total anthocyanins compared to uncoated fruits during storage of up to 16 days. The phenolic compounds of A. vera gel were analyzed by HPLC, and the most abundant compounds were found to be caffeic (30.77 mg/mL), coumaric (22.4 mg/mL), syringic (15.12 mg/mL), sinapic (14.05 mg/mL), ferulic (8.22 mg/mL), and cinnamic acids (7.14 mg/mL). Lemongrass EO was analyzed by GC–MS, and the most abundant compounds were identified as α-citral (neral) (40.10%) ꞵ-citral (geranial) (30.71%), γ-dodecalactone (10.24%), isoneral (6.67%), neryl acetal (5.64%), and linalool (1.77%). When the fruits were treated with 20% or 40% A. vera gel along with 1% lemongrass, their total phenolic content was maintained during the storage period (from 4 to 8 days). The antioxidant activity was relatively stable during the 8 days of cold storage of the fruits coated with A. vera gel combined with lemongrass EO because the activity of both 20% and 40% gel was greater than that for the other treatments after 12 days of storage in both experiments. Moreover, all the treatments resulted in lower numbers of total microbes at the end of the storage period compared with the control treatment. This study indicates that the use of Aloe vera gel with lemongrass EO as an edible coating considerably enhances the productivity of strawberry fruits and the treatment could be used on a commercial scale.

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The present investigation was carried out on Diamant potato tubers (Solanum tuberosum L.), harvested at their commercial maturity stage (May, 2017) in a private farm at Kom Hamada Behira Governorate, Egypt. The selection of tubers was based on size, absence of physical injuries, mechanical damage and disease infection. Tubers were packed in net plastic boxes (15 kg/ box), and were surface-disinfected by dipping in 2% sodium hypochlorite for 2-4 mins, then rinsed with tap water and air-dried. Potato tubers were immersed in solutions containing chlorpropham (CIPC) at 0, 50, 75 and 100 ppm and jasmonic acid (JA) at 0, 0.001, 0.01 and 0.1 mM/L, either alone or in combinations for 20 minutes and then were cured in the dark for one week at 20°C and 75% RH. After curing, the tubers were placed in the dark cold storage room for long-term storage (140 days) at 10±1°C and 85±5% relative humidity (RH). Treatments were distributed in design with three replicates for each treatment (one replicate = one box of 15 kg tubers).Tuber's firmness, dry matter, starch, acidity and ascorbic acid increased, while SSC and total sugars decreased with increasing concentration of CIPC. Chlorpropham at the concentration of 75 ppm of decreased the weight loss, decay and sprouting percent during cold storage or after removal from cold storage and kept at ambient temperature as compared with 50 or 100 ppm and control. Furthermore, the storability and shelf life of potato tubers have been extended significantly with 75 ppm in both the storage temperature conditions. Likewise, applied of jasmonic acid at rate of 0.01 mM JA/L caused noticeable increase in tubers firmness, dry matter, starch, acidity and ascorbic acid contents. Meanwhile, soluble solids content, total sugars, weight loss, decay and sprouting percent decreased during storage as compared with the other concentrations of jasmonic acid (0.001 or 0.1 mM JA/L) and the untreated tubers. Additionally, the storage and shelf life of tubers have been extended significantly with 0.01 mM JA/L dips during cold storage or ambient temperature at 25±2°C and 75-80 % RH.