Seyed Mehdi Mirbaqeri; Rouhollah Karimi; Mousa Rasouli
Abstract
In order to investigate the effect of foliar application of potassium sulfate (K2SO4; 0, 1.5 and 3 percent) and iron chelate (Fe-EDDHA; 0, 0.5 and 1 percent) on fruit set, fruit yield and quality, leaf mineral nutrient content, raisin yield and autumn and winter cold tolerance of ‘Bidaneh-Sefid’ ...
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In order to investigate the effect of foliar application of potassium sulfate (K2SO4; 0, 1.5 and 3 percent) and iron chelate (Fe-EDDHA; 0, 0.5 and 1 percent) on fruit set, fruit yield and quality, leaf mineral nutrient content, raisin yield and autumn and winter cold tolerance of ‘Bidaneh-Sefid’ grapevine, a factorial experiment was done based on randomized complete blocks design in a commercial vineyard in Bahareh village of Malayer city during 2016-17. The highest fruit set percentage and yield was achieved in 1.5 percent of K2SO4 in combination with 0.5 percent iron chelate. Berries K, Fe and Mn concentration had a positive and significant correlation with fruit yield per vine. Raisin yield was found to be highest in combined treatments of 1.5 percent K2SO4 and 1 percent Fe-EDDHA and the lowest raisin yield was related to control vines. The highest autumn cold hardiness was recorded in K2SO4 (3%) × Fe-EDDHA (1%) treated vines. However, the highest winter cold tolerance was achieved in K2SO4 (3%) × Fe-EDDHA (0.5%) treated vines. The lowest cold tolerance was observed in control vines. There was a positive and significant correlation between cold tolerance and K content and negative correlation with Mg concentration. Totally, the highest fruit and raisin yields and their desirable qualities were obtained with K2SO4 and Fe-EDDHA at moderate concentration. However, the highest buds cold tolerance was obtained with the combination of these fertilizers at higher doses.
Shiva Bazl; Rouholah Karimi; Ahmad Ershadi; Alireza Shahbodaghlo; Mousa Rasouli
Abstract
Cold stress is one of the limiting factors in production of greenhouse vegetables. Chemicals offer useful approach to reduce low temperature-induced damages. This study was conducted to evaluate the effect of foliar application of methyl jasmonate (MeJA) at concentrations of 0 (control), 50, 100, 200 ...
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Cold stress is one of the limiting factors in production of greenhouse vegetables. Chemicals offer useful approach to reduce low temperature-induced damages. This study was conducted to evaluate the effect of foliar application of methyl jasmonate (MeJA) at concentrations of 0 (control), 50, 100, 200 µM) on electrolyte leakage (EL), relative water content (RWC), soluble carbohydrates, proline, chlorophyll content and chilling index of greenhouse- grown cucumber (Cucumis sativus L. cv ‘Negin’) in 4-6 leaf stage. MeJA was sprayed two times/day on cucumber seedling in a greenhouse of Bu-Ali Sina University, as a factorial based on completely randomized design with five replications per treatment, inlate- summer of 2013. Two days after spraying, seedlings were transferred from 25ºC to cold chamber and were subjected to chilling treatments of 15, 10 and 5 ºC for 4 hours. The EL of all plants increased with reducing the temperature. However, in MeJA-treated plants, especially in application of 200 µM, a lower leaf EL was observed. A clear increase in soluble carbohydrates and proline concentration was observed with decreasing temperature from 15 to 5ºC in all plants while in MeJA -treated seedlings, especially in application of 200 and 100µM, a greater amount of these osmolytes were observed in compared to control. Moreover, exogenous application of MeJA reduced RWC and visual damage of cold-stressed seedlings but increased chlorophyll content in compared to control plants. These changes correlated with the increment of cold tolerance in the cucumber plants. The results indicated that MeJA application especially at 200 µM, has the capacity to improve chilling tolerance of seedlings and can be used as a prophylactic tool to protect against chilling injury of cucumber cultivars in greenhouses