Summary: Root morphology can be affected by many factors such as microorganisms. To determine the effect of effective microorganisms (EM) on the root morphology of sweet corn under salt stress, a factorial experiment was carried out in a randomized complete block design with three replications in Islamic Azad University of Sabzevar in 2013. Examined factors included application method of EM (soil application, foliar application and soil+foliar application) and intensity of salinity (0, 25, 50, 75 mM). Commercial solution of EM was applied at30liters per hectare for soil application and foliar application during five-leaf stage. The highest root dry weight, root density and membrane stability were observed in soil application while the highest root volume, root length, root and shoot dry weight occurred when soil and foliar application were performed together. With increasing intensity of salinity, all traits decreased and the highest traits were observed in the control treatment. Soil application of EM in comparison with other methods alleviates effects of salinity under saline conditions.

The present study aims to model and optimize phenolic acids productions from Lactuca undulate root and leaf-derived callus using the feed-forward Artificial Neural Network (ANN) model. For this purpose, the effect of different concentrations (0, 0.1, 0.5, 1, and 2 mg/l) of Kin in combinations with or without 2,4-D and/or NAA was investigated on callus induction and phenolic acids production. A multi-layer perceptron ANN was applied to correlate the output parameters (cichoric acid, chlorogenic acid and caffeic acid contents) to input (Kin, 2,4-D and NAA) training parameters. A single hidden layer with 5, 10, 15, 20, 25, 30, 35 and 40 neurons was used to optimize ANN architecture. Sum squared error (SSE), Relative Error (RE) and correlation factor (R2) were applied to identify the performance of ANN models. According to the obtained data, the feed-forward neural network with tangent-sigmoid (3-30-1), tangent-tangent (3-15-1) and tangent-tangent (3-35-1) activation function was found as the best model to predict cichoric acid, chlorogenic acid and caffeic acid production from leaf-derived callus, respectively. Meanwhile, ANN with activation function of tangent-tangent (3-20-1), tangent-tangent (3-25-1) and sigmoid-sigmoid (3-20-1) were the most effective models to predict the amount of cichoric acid, chlorogenic acid and caffeic acid from root-derived callus, respectively. In the current study, there was a strong correlation between experimental and predicted data. These results demonstrated that the selected ANN model could predict the effects of plant growth regulators on phenolic acids production using callus culture method.

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Background: Today, stress moderators are employed for mitigating the negative effects of environmental stress as the main cause of reduced yields of crops. In this study, the impacts of time and types of stress moderators on agrophysiological responses of cotton under saline conditions on different planting dates were investigated during 2017 and 2018. A split-plot factorial experiment was carried out in a randomized complete block design with 3 replications. Sowing dates (early and late) were considered as the main plots and stress moderator type at 4 levels (control, 2mM Salicylic acid (SA), 100 mM Glycine betaine (GB), and 100 μM sodium nitroprusside (SNP)) and application time (flowering and flowering+bolling stages) were regarded as the sub plots. Results: The delayed planting reduced plant height, reproductive branch number, number of bolls, boll weight, 1000-seed weight, biological yield, seed cotton yield, lint yield, chlorophyll a, chlorophyll b, carotenoids, total chlorophyll, sodium, potassium and proline content. Spraying with the stress moderators alleviated soil salinity effects on yield, yield components and biochemical traits of cotton. SA spraying led to maximum height, 1000-seed weight, biological yield, seed cotton percentage, seed cotton yield, and potassium content. SNP spraying yielded the greatest number of bolls per plant, boll weight, lint yield, and proline content. The highest plant height, chlorophyll a, chlorophyll b, carotenoids and total chlorophyll content resulted from GB spraying. Yield, yield components, and biochemical traits did not respond to the stress moderator types in the delayed sowing date, while the highest chlorophyll a, carotenoids, proline content, the number of bolls per plant and seed cotton yield was resulted from spraying with SNP in early planting. No statistically significant differences were observed between spraying with SNP and SA in most studied traits. Conclusions: The result suggests that cotton planting at an appropriate date and SNP spraying could be recommended for producing the most suitable yield under saline conditions.