Ghorban Khodabin; Zeinolabedin Tahmasebi-Sarvestani; Amir Hossein Shirani rad; Esmaeil Bakhshandeh; Mojdeh Sadat Khayat Moghadam; Shahryar Kazemi; mahsa rafati alashti; ali heidarzadeh
Abstract
In order to study the effects of late-season drought stress and foliar application of zinc sulfate (ZnSO4) and manganese sulfate (MnSO4) on physiological characteristics and yield of rapeseed cultivars, a factorial split-plot test has been conducted in a randomized complete blocks design for two cultivation ...
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In order to study the effects of late-season drought stress and foliar application of zinc sulfate (ZnSO4) and manganese sulfate (MnSO4) on physiological characteristics and yield of rapeseed cultivars, a factorial split-plot test has been conducted in a randomized complete blocks design for two cultivation years (2017-2019) in Karaj, Iran. The experimental treatments include two levels of irrigation (full irrigation (control) and withholding irrigation from flowering stage) and four levels of foliar application (control, ZnSO4, and MnSO4, separately, as well as their combined application) as factorial in the main plots, with rapeseed genotypes (Nima, Niloofar, and KS7) considered as subplots. Combined foliar application of zinc and manganese sulfate under full irrigation conditions increase the content of seed oil and soluble carbohydrates by 3% and 11%, respectively, compared to the control. On the other hand, withholding irrigation from flowering stage increases the percentage of seed oil and leaf proline content, compared to the control by 9% and 5.2%, respectively. Niloofar genotype has had the highest seed yield (5261 kg/ha) under full irrigation conditions, i.e. 9% and 11.8% higher than KS7 and Nima genotypes, respectively. Nima genotype with 3371 kg/ha has had the highest yield in the conditions of withholding irrigation. In general, in both irrigation treatments, simultaneous foliar application of zinc sulfate and manganese has had the greatest impact on the physiological traits of the studied genotypes, thus Niloofar genotype is recommended for full irrigation and Nima genotype for interrupted irrigation.
Saloomeh Taheri; Taher Barzegar; Vali Rabiei; Hossein Rabi Angoorani
Abstract
Salinity is one of the most important environmental stresses that affect plant growth. In order to study the effect of Salicylic Acid (SA) on some physiological characteristics of basil under salinity conditions, the experiment was set out as a factorial design in the base of RCBD with three replications. ...
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Salinity is one of the most important environmental stresses that affect plant growth. In order to study the effect of Salicylic Acid (SA) on some physiological characteristics of basil under salinity conditions, the experiment was set out as a factorial design in the base of RCBD with three replications. Treatments consisted of four NaCl salinity levels (0, 50, 100, 150 mM), salicylic acid at three levels (0, 0.25, 0.5 mM) and two cultivars of basil (purple and green). Results showed that salinity significantly decreased amount of chlorophyll, carotenoid and leaf relative water content. Application of SA increased amounts of chlorophyll, carotenoid and leaf relative water content. The amount of proline, stomatal resistance and electrolyte leakage in leaves increased significantly under salinity condition and decreased with treatment of salicylic acid. The highest amount of chlorophyll b (0.617 mg/g FW-1) and the minimum electrolyte leakage (30.4 percent) was observed with application of 0.5 mM SA under of 0 mM NaCl concentration in green and purple basil cultivars, respectively. Also, the maximum content of proline (11.4 µg/g FW-1) and the lowest rate of stomatal resistance (7.8 s/cm-2) were obtained under 150 mM NaCl in purple and green basil cultivars, respectively. According to the results, application of salicylic acid can be proposed to improve plant growth under salinity conditions.
Mehdi Rezaei; Abass Rohani
Abstract
Stomatal resistance has an important role in plant water exchange and photosynthesis under stress condition hence it is a key parameter in ecological and biological models. In the present research, optimum values of effective parameters on stomatal resistance of olive to achieve maximum stomatal resistance ...
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Stomatal resistance has an important role in plant water exchange and photosynthesis under stress condition hence it is a key parameter in ecological and biological models. In the present research, optimum values of effective parameters on stomatal resistance of olive to achieve maximum stomatal resistance were determined. Salinity levels (0, 25, 50 and 100 mg/l NaCl), percentage of leaf ions (chlorine, sodium, potassium, calcium, phosphor, magnesium), K/Na ratio, wet weight of leaf (mg), leaf area (cm2), relative water content (%) and leaf area ratio (cm2/g) were considered as effective parameters in stomatal resistance of olive. The stomatal resistance was modeled as a function of the variables using a radial basis function (RBF) neural-network model. The predicted results demonstrated that the neural network could provide a good performance since prediction results were in rather good agreement with measured results. The maximum percentage error between predicted and experimental data was less than 2.57% and the correlation coefficient between them was 0.994. Also, the statistical comparison between the predicted and experimental data indicates the reliability of the predictions using a RBF neural-network model. The trained neural network is used as objective function to get optimal parameters using the genetic algorithm. The optimum values of the parameters obtained at a 100, 0.15, 0.57, 0.78, 0.32, 0.06, 0.17, 1.29, 26.63, 5.03, 0.76 and 72.89 for the first parameter through the last parameter, respectively.