نشریه علوم به زراعی گیاهی
سال یازدهم شماره 2 (پاییز و زمستان 1400)

n order to study the effect of application of different biochar species and phosphate solubilizing microorganisms on soil enzymatic activity and agronomic traits of safflower during two cropping seasons of 2018 and 2019 in a part of cultivated lands of Sardorood district of Razan, Hamedan province, an experiment as split plots on the basis of randomized complete block design with three replications was implemented. The main factor at 4 levels of biochar including: cow manure, wheat straw, wood biochar and control. The sub factors were phosphate solubilizing microorganisms included the mycorrhizal fungi (Glomus etunicatum and G. mosseae), Bacillus lentus, Pseudomonas fluorescence and control. The results of mean comparison showed that highest number of heads per plant (8.12, 8.14) and the maximum seed weight (24.60 g) were observed in mycorrhizal inoculation treatments and the lowest were in control treatment, also the highest number of heads per plant (8.26) and seed weight (24.18 g) was observed in cow manure biochar treatment. The results of mean comparison showed that the highest biological yield (5454 kg/ha) was obtained in mycorrhizal inoculation treatments. Also, application of other phosphate solubilizing bacteria increased the biological yield of safflower compared to the control treatment.

Salinity is one of the most important issues that significantly reduce the area of arable land and also the amount of production and product quality. Identification and domestication of salinity-resistant plant species which have economic value is an important strategy. This study was conducted for evaluation of oil percent and fatty acids content in some wild halophyte’s plants. The results showed that the highest percentage of oil (14.20%) was obtained in Salicornia saline plant and the lowest amount (2.65%) was obtained in Halostachys caspica salinity plant. The highest levels of palmitic acid, stearic acid and linolenic acid were observed in Halostachys caspica. The highest amount of linoleic acid was obtained in Salicornia, Anabasis setifera and prickly pear plants and the lowest amount was obtained in Halostachys caspica. The highest total of saturated fatty acids was obtained in Halostachys caspica plant. The highest total of unsaturated fatty acids was observed in Salicornia and saline plants. In general, the results of this study showed that the use of halophyte species as a source of vegetable oil is economical, because these plants do not compete on quality soil and water with conventional crops. In addition, the percentage of unsaturated fatty acids in all studied species except Halostachys caspica was shown to be high and equal to most oilseeds. Due to the ability of these plants to grow in saline soils, they can be used as a resource of oil extraction in this condition.

To investigate the effects of defoliation and nitrogen foliar application on yield physiology of sunflower, a experiments was performed in a randomized complete block design with split-plot arrangement in Gonabad region during 2015 and 2016 seasons. Nitrogen consists of two levels of spraying in flowering time (N1) and control (N2) in the main plots. Defoliation consists of five levels: Control (D1), 1/3 defoliation at 8th leaf stage (D2), 2/3 defoliation at 8th leaf stage (D3), 1/3 defoliation at beginning of the flowering (D4), 2/3 defoliation at beginning of the flowering (D5). In nitrogen deficiency conditions, by cutting 1/3 of the leaves at the first of the flowering, grain yield increased by 28% (0.54 to 0.75 kg ha-1) compared to control treatment .In the conditions of nitrogen consumption, after removing the 2/3 of the leaves at the first of the flowering, the amount of dry matter transfer reallocation from the stem to the grain showed a significant increase compared to the control, while in the conditions of non-nitrogen consumption, defoliation treatments had a slight effect on the contribution of stem reserves. Under the conditions of nitrogen deficiency, the negative effect of sink size restriction on grain yield is more than the negative effect of source strength restriction. constraints than the source power limitations On the practice Gain rejection is more. Plant breeders focus their programs to increase the efficiency of nitrogen consumption in order to increase the strength of the sink and reduce extra leaves with low efficiency in grain filling.

In order to evaluate the efficacy of 2,4-D and tribenuronemethyl herbicides on ecotypes of hoary cress (Cardaria draba L. Desv) and the possibility of reducing the recommended dose, the dose-response experiment was performed as a randomized complete block with three replications in Ghaem Park greenhouse, Tehran in 2020. The studied ecotypes were Salmas, Rafsanjan, Semirom, Shahrekord, Baft, Birjand, Semnan and Karaj and the two herbicides were used in four doses (25, 50, 75 and 100% of the recommended dose) in the 4 to 6 leaf stage. The results showed that 2,4-D was more effective in controlling hoary cress ecotypes than tribrenuronethyl. By applying 100% of the recommended dose of 2,4-D, the dry weight of hoary cress ecotypes decreased by 91-99%. The dose of ED50 in response to 2,4-D and tribenuronemethyl for hoary cress ecotypes ranged from 0.41 to 0.89 lit hec-1 and from 8.5 to 17.27 g hec-1, respectively. Based on the estimated ED50 dose, the most sensitive and resistant ecotypes of hoary cress to both herbicides were Semirom and Karaj, respectively. Due to the 90% reduction in dry weight of Semirom, Baft, Shahrekord and Rafsanjan in 75% of the recommended dose of 2,4-D, the dose required to control these ecotypes can be reduced and less herbicide used.

In order to investigation the amount of energy consumption and the relationship between input and output energy in wheat production, 10 wheat farms in Sari region (plain and mountainous) were selected. To collect information from the farms, first, all agricultural activities were divided into 8 parts: land preparation, planting, fertilizing, plant protection, weed control, irrigation, harvesting, and transportation to the factory. Results showed that the most of the fuel used for land preparation, which was significantly different from other agricultural operations. The average input energy in 10 farms was 14597.76 M J.ha-1. Among the consumer inputs in 10 wheat farms, nitrogen fertilizer is equivalent to 35.33% of the total input energy. Indirect energies had an average of 11245.69 MJ.ha-1 and direct energy had an average of 3351.26 MJ.ha-1. The average grain yield in 10 wheat fields was 4275 kg.ha-1. The average energy efficiency in 10 wheat fields was 3.42 MJ.ha-1. In general, the results showed that one of the most important factors in reducing economic productivity in an agricultural system, is the excessive consumption of inputs, which in the long term, the production of this this crop will be at risk.

In this research, we try to predict the yield of rainfed barley in Khorasan provinces using climatic parameters and two methods of artificial nervous netwework (Ann) and fuzzy neural system (Anfis). Calculations were performed with MATLAB software and then the statistical indices of correlation coefficient (R2), root mean square error (RMSE) and full mean error (MAE) were used to evaluate the performance of the models. Last year's yield and rainfall had an effective role in reducing prediction error and increasing correlation coefficient in both Ann and Anfis methods. Last year's yield and evapotranspiration made the Anfis method more accurate than the Ann method. The results of both Anfis and Ann methods for model L inputs, which included rainfall, relative humidity and last year's yield, showed that this model achieved the highest accuracy among the input models. However, in the Anfis method for model E inputs, which included evapotranspiration, rainfall, relative humidity and minimum temperature, the results showed that it was more accurate than the Ann method. The greatest difference in accuracy in estimating yield between the two Anfis and Ann methods was observed with R inputs model, which includes moisture inputs, Dew point temperatures and maximum temperatures. The presence of radiation parameters at the inputs reduced the accuracy of yield estimation in both methods. Overall, the Anfis method was more accurate in estimating yield than Ann.

Salinity stress is one of the important stresses affecting germination, growth, production and quality characteristics of wheat. Researchers have described salt stress as the accumulation of ions such as sodium, sulfate, and chlorine in the rhizosphere environment in a way that disrupts the natural growth of plants. Salinity stress through reducing the cell pressure, inhibition the functioning of membranes, affecting the activity of enzymes, inhibiting photosynthesis and inducing ion deficiency due to the reduction of ion transport and other physiological processes causes a decrease in growth, leaf area index, biomass and grain yield. Wheat cultivars show different reactions to soil and water salinity. Increasing tolerance to salinity in bread wheat cultivars is related to a decrease in sodium concentration in the plant and also a decrease in the sodium to potassium ratio in the leaves. Separation of sodium in leaves and preferably potassium is related to the presence of D genome in hexaploid wheats. In general, investigating physiological reactions, especially in salinity tolerant genotypes, is helpful for plant breeders to release salinity tolerant genotypes. This research is to study the effect of salinity stress on some characteristics Physiological and growth of wheat has been discussed.