فصلنامه پژوهشهای زراعی در حاشیه کویر
سال پانزدهم شماره 2 (تابستان 1397)

Optimal management of irrigation water and optimal use of food under salinity and drought is very important. The objective of this research was assessment root water uptake function of tomato under simultaneous water, salinity and   different levels of nitrogen stresses. The experiments were carried out on tomato plant in a factorial randomized complete block design with three replications. The treatments consist four levels of water irrigation (50, 75, 100 and 100 percent of water requirement), Six levels of salinity (1, 2, 4, 6, 8 and 10 dS/m) and three levels of nitrogen including zero, 50 and 100 percent of the fertilizer needs. Water, salinity and nitrogen stresses treatments were applied from the flowering plant. .The results showed under simultaneous salinity and nitrogen stresses, modified MB model and under simultaneous water and salinity stresses, MB-H, MB-F,MB-D and MB-VG models had better accuracy and MB-F Model in comparison with other models had the best fit against the measured data. In simultaneous water, salinity and nitrogen stresses multiplicative MB-MB-F model is the best fit than other suggested

Optimal management of irrigation water and optimal use of food under salinity and drought is very important. The objective of this research was assessment root water uptake function of tomato under simultaneous water, salinity and   different levels of nitrogen stresses. The experiments were carried out on tomato plant in a factorial randomized complete block design with three replications. The treatments consist four levels of water irrigation (50, 75, 100 and 100 percent of water requirement), Six levels of salinity (1, 2, 4, 6, 8 and 10 dS/m) and three levels of nitrogen including zero, 50 and 100 percent of the fertilizer needs. Water, salinity and nitrogen stresses treatments were applied from the flowering plant. .The results showed under simultaneous salinity and nitrogen stresses, modified MB model and under simultaneous water and salinity stresses, MB-H, MB-F,MB-D and MB-VG models had better accuracy and MB-F Model in comparison with other models had the best fit against the measured data. In simultaneous water, salinity and nitrogen stresses multiplicative MB-MB-F model is the best fit than other suggested

In order to investigate the effect of hexaconazole foliar application on yield and biochemical characteristics  of grain corn of KSC704 cultivar under cut irrigation conditions, an experiment was conducted as split plots in a randomized complete block design with three replications. The main treatments of the experiment are: S0 = Normal irrigation, S1 = Cut Irrigation in stem stage, S2 = Cut Irrigation at flowering stage, S3= Irrigation interruption in seed filling stage and sub-treatments were including: M0= control (not applicable), M1= 25 mg / l , M2 = 50 mg / l. The results showed that cut irrigation reduced grain yield but hexaclonazole foliar application increased the following trait. Hexaclonazole foliar application of 25 and 50 mg / l increased the antioxidants superoxide dismutase, catalase and peroxidase and decreased the biomarker of malondialdehyde, di tyrosine and dihydroxyguanosine degradation significantly. And through hormonal changes increased drought tolerance in corn.

In order to study the effect of different levels of Daljin growth regulator on agronomic and physiological traits of barley under salt stress, a factorial experiment was conducted in a completely randomized design at the Faculty of Agriculture, Islamic Azad University, Varamin-Pishva Branch, in 2016-2017. The treatments consisted of salt stresses at zero (control), 75 and 150 mM, and foliar application of Daljin in zero (control), 0.5, 1 and 2 at 1000. The measured traits included 1000 seed weight, yield of a plant, seed protein percent, proline, catalase and leaf relative water content. The results showed that salt stress reduced the weight of 1000 seeds, yield of a plant, relative water content of leaves and increased protein content of grain, catalase and proline. Also, Daljin spraying resulted in 1000 seed weight gain, yield of a plant, relative water content of leaves and proline. In the salinity conditions of 75 mM, the highest yield of a plant was related to treatments 1 and 2 at 1000 Daljin (8.49 and 8.9 grams respectively). The highest protein content of the seeds was 16.6% in the 150 mM salinity treatments and in the absence of spraying. It can be concluded from the results of positive effects of Daljin, especially in salt stress conditions, and the reduction of the negative effects of salinity in barley plants, and the highest positive effect was obtained by spraying 1 and 2 at 1000 dalijin.

To investigate the effect of different levels of sodium nitroprusside and cadmium on green basil cultivar, a pot experiment was conducted in the Faculty of Agriculture, Islamic Azad University, Varamin-Pishva Branch in 2017 as a factorial experiment in a completely randomized design with three replications. Experimental treatments include: three levels of sodium nitroprusside foliar application at the rate of: zero (control of pure water foliar application) (N1),50μM (N2), 100 μM (N3) and four levels of cadmium in the amount of: Zero (control) (C1), 10 ml ‌ G / kg soil (C2), 20 mg/kg soil (C3) and, 30 mg / kg soil (C4). The results showed that the interaction effects of the treatments on the studied traits were significant. With increasing cadmium, the amount of leaf chlorophyll decreased and finally the rate of assimilation decreased and the leaf weight decreased. The highest plant height, leaf dry weight per plant, essential oil percentage and essential oil yield, methyl cavicol percentage were achived from 100 μM sodium nitroxide and control (N3*C1) treatment and the lowest plant height, leaf dry weight were obtained. In plant, cytoplasmic membrane stability, essential oil percentage and essential oil yield were obtained from control treatment (spraying with pure water) and application of 30 mg / kg cadmium in soil (N4*C4). The results showed that the negative effects of cadmium stress were largely eliminated by the use of sodium nitroxide.

This research was accomplished in 2016 at greenhouse for study of different concentration effects of seaweed (Sargassum) extract on qualitative and quantitative characteristics of Menthapiperita. Present research was done in a factorial design with a completely randomized four replications. The main factor was different concentrations of seaweed extract with 0, 10, 20, 30 and 40 percent, while the subplot was different spray time in two period types of every 5 and 10 days. The results showed that the concentration of chlorophyll a in peppermint increased with decreasing the time of foliar application and was not significant at different concentrations of algal extract in 30 and 40% treatments on the studied traits. The effect of different concentrations of sargassum algae extract on plant minerals including nitrogen was positive at a concentration of 20% in 10 days of treatment. Therefore, in order to increase the protein and essential oil of peppermint, the concentrations of sargassum extract in this study can be used. In general, it can be concluded that the use of algae extract in the production of peppermint was not considered appropriate due to reduced growth rate and no positive effect on plant essential oil, and from concentrations of 20% or more as a herbicide can be Used.