Aliyeh Shafiei; Mehdi Hadadinejad; Saeed eshghi; kamran ghasemi
Abstract
The present research tries to investigate the effect of potassium silicate and mycorrhizal fungus on heat stress tolerance of strawberries and evaluate the possibility of increasing plant tolerance to heat at research greenhouse in Sari Agriculture and Natural Resources University at 2019. It is in a ...
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The present research tries to investigate the effect of potassium silicate and mycorrhizal fungus on heat stress tolerance of strawberries and evaluate the possibility of increasing plant tolerance to heat at research greenhouse in Sari Agriculture and Natural Resources University at 2019. It is in a completely randomized factorial design with three factors including two levels of mycorrhizal fungi (presence and absence of mycorrhizal fungi), three levels of potassium silicate (0, 50 and 100 mg.l-1) spray in heat stress (25 and 41 °C) with three replications. The results show that application of potassium silicate reduces the Photosynthtic active radiation (PAR) damage in strawberry leaves, which PAR of leaves bottom reduce three folds in comparison to the control, when the PARtop is 1133 umol.m2.s-1. In contrast, treatment of the plant with potassium silicate in the presence of mycorrhiza prevented increases transpiration and stomatal conductivity for water cooling the leaves during heat stress. Inoculation of the roots with mycorrhiza fungi leads to a wide network of hyphae in root uptake, improving water use efficiency by up to 72%, which in turn results in increaseed net photosynthesis. However, heat stress increases minimum fluorescence and reduces maximal quantum efficiency of photosystem II. But the simultaneous application of mycorrhiza and potassium silicate is able to improve this index to a good level (0.76). Finally, it has been found that high temperature stress affects many photosynthetic factors of strawberry plant that the use of potassium silicate in combination with mycorrhizal fungus, despite their separate use, to a large extent prevents heat damage to different parts of the plant.
Ali Akbari; Orang Khademi; Yavar Sharafi; Seyed Jalal Tabatabaei
Abstract
Strawberry is sensitive to salinity stress. This experiment was conducted as factorial based on RCBD design to investigate the effects of putrescine treatments on reducing harmful effects of NaCl salinity stress in strawberry at Shahed University in 2015. NaCl treatments, 0, 25 and 50 mM, were applied ...
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Strawberry is sensitive to salinity stress. This experiment was conducted as factorial based on RCBD design to investigate the effects of putrescine treatments on reducing harmful effects of NaCl salinity stress in strawberry at Shahed University in 2015. NaCl treatments, 0, 25 and 50 mM, were applied in hydroponic medium on from the root zone of ‘Camarosa’ cultivar. Putrescine treatments were also applied at 0, 1.5 and 3 mM as foliage spray during growth period in 4 times with 15 days intervals. The results showed that, NaCl treatment especially at 50 mM, reduced shoot length, shoot fresh and dry weight, root fresh and dry weight, leaf number, leaf chlorophyll content, fruit number, fruit fresh and dry weight, yield and titratable acidity, and increased anthocyanin and total soluble solid content. Salinity stress had no effects on the root length. Application of 1.5 and 3 mM putrescines reduced harmful effects of salinity stress. Putrescines increased almost all characteristics under salinity condition and reduced total soluble solid content. Therefore, according to the results, putrescine, in both levels of 1.5 and 3 mM, could be a well strategy to reduce the limitation of salinity stress in strawberry production.
Safoura Kazemi; Rahim Barzegar; Abd-Alrahman Mohammadkhani
Abstract
The present investigation was carried out to evaluate the effect of vermivash on yield and leaf nutrient status of strawberry "Govieta" at research greenhouse of Shahrekord University in 2013. Treatments were included control (without vermiwash foliar spray) and different concentration of vermiwash (10, ...
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The present investigation was carried out to evaluate the effect of vermivash on yield and leaf nutrient status of strawberry "Govieta" at research greenhouse of Shahrekord University in 2013. Treatments were included control (without vermiwash foliar spray) and different concentration of vermiwash (10, 15 and 25 percent) that spryed at 1, 2 and 3 weeks interval. Vermiwash was extracted from cow manure vermicompost through earthworm Eisenia foetida. The experiment was conducted in completely randomized design (CRD) with three replications. The results showed that there was significant difference between vermiwash treatments and control for the leaf elements of N, K and Fe, but was not significant for the other macro and microelements. Leaf Fe concentration increased up to excessive level in 25 percent concentration with weekly interval. Foliar spray of 25, 15 and 10 percent vermiwash with two-weeks intervals considerably enhanced the number of fruit and yield per plant, but decreaced fruit weigth average a little. Increasing the yield per plant ranged between 24 and 68g for various vermiwash treatments in comparison with control. Vermiwash treatments had no effect on inflorescence number per plant and flower number per inflorescence. Foliar spray of 15 and 10 percent vermiwash with two-weeks interval improved the yield of strawberry "Govita".