نشریه پژوهش های به زراعی
سال چهاردهم شماره 2 (تابستان 1401)

Cycocel as a growth regulator and micronutrient elements can moderate the effects of drought stress. This research was conducted in order to investigate the effect of foliar spraying of cycocel and iron and zinc micronutrient elements on the yield and physiological traits of wheat pishgam cultivar under drought stress conditions in a private farm in Rabat Karim, Tehran, during the cropping years of 2016-2017 and 2017-2018. The experiment was carried out in the form of split plots in the form of a randomized complete block design in three replications. In this experiment, irrigation at two levels (I1: full irrigation (custom of the region) and I2: interruption of irrigation at the beginning of the spike emergence stage or 51 Zadoks) As the main factor, cycocel at two levels (C1: no use (spraying solution with pure water) and C2: consumption of cycocel at the rate of 0.5 liters per hectare) and foliar application of micronutrient elements in two stages of stem formation and spike emergence at four levels (F1: no use (pure water spray solution), F2: iron foliar application, F3: zinc foliar application, and F4: iron foliar application + zinc (each at a ratio of 3 per thousand) As sub-factors, they were factorial placed in sub-plots. The results of composite data analysis showed that the main effect of irrigation, cycocel foliar application and the interaction effect of irrigation × cycocel at the level of five percent and foliar application of micronutrient elements at the level of one percent was significant on grain yield. The results of comparing the averages of the effect of irrigation and cycocel on grain yield showed that the highest grain yield belonged to the cycocel application treatment under normal irrigation conditions with an average of 7077 kg/ha. The use of cycocel in normal irrigation conditions and also in stress conditions in the spike stage or 51 Zadoks increased grain yield. This increase was more evident under normal irrigation conditions. The results of comparing the averages of the effect of foliar application of micronutrients on grain yield showed that iron + zinc foliar application had the highest grain yield with an average of 5543 kg/ha, and the lowest grain yield belonged to the control treatment with an average of 4638 kg/ha. According to the obtained results, although the drought is causing damage to wheat, but cycocel, iron and Zinc foliar application partially compensated the damage caused by drought stress.

Paclobutrazol is a plant growth regulator that reduces gibberellin in plants. In this research, paclobutrazol and nitrogen foliar application was investigated on the yield and grain quality of superwheat hybrid cultivar in Karaj region, in the form of split plots in the form of randomized complete block design with three replications in the crop year 2017-2018. The main factor in this experiment included three different levels of nitrogen (60, 105 and 150 kg/ha) from the urea source, the second factor included two levels of paclobutrazol (zero and 200 mg/liter). The results showed that the application of paclobutrazol increased the grain yield and grain quality of wheat, and with the increase in the amount of nitrogen, the yield, yield components and quality of wheat grain increased. The highest amount of seed yield was 14.05 ton/ha, the number of seeds per spike was 89.35 seeds, the harvest index was 43.41% and the seed protein was 12.44% related to the mutual effects of nitrogen 150 kg per hectare and the application of paclobutrazol. Therefore, in order to increase the yield and quality of wheat grain, it is recommended to use paclobutrazol along with nitrogen at 150 kg per hectare.

In order to investigate the effect of Effect of brassinosteroids and sodium nitroprusside (SNP) foliar application on physiological, biochemical and morphological traits of Borago (Borago officinalis L.) under salt stress conditions, based on a greenhouse experiment was conducted in Shahriar region in 2016-2017. The experiment was conducted as factorial based on completely randomized design with four replications. In which salinity stress from the source of Nacl at three levels (0, 40 and 80 mM), Nitroprosium sodium sulfate was applied at three levels (0, 75 and 150 μM) and brassinosteroids at two levels (0 and 1.5 μm) Were considered. The simple effect of brassinosteroid and sodium nitroprusside on all experimented traits and the interaction effect of experimental factors on carotenoid and xanthophyll content were significant. In these conditions, after increase in salinity stress, the pigment content decreased and these traits improved with anti-stress compounds consumption. So the highest amount of carotenoid and xanthophyll with 1.6667 mg/g and 0.3344 mg/g were obtained with 150 μM sodium nitroprusside and 1.5 μM brassinosteroids consumption.

Salinity stress is one of the important stresses in reducing the yield of plants, especially leafy plants, and it is very important to provide solutions to deal with it. For this purpose, a factorial experiment was conducted in the form of a completely randomized design in four replications in a greenhouse located in Naziabad, Karaj on llolaroza lettuce hydroponically under salt stress conditions. The factors of this research included humic acid in four concentrations 0 (control), 500, 1000 and 1500 mg/l and salinity stress at two levels no stress (control) and 30 mM. The results showed that application of salinity stress decreased the yield of Lolla rossa lettuce. The application of humic acid and increasing its concentration increased the quantitative and qualitative performance of this plant and reduced the negative effects of salinity stress. The highest yield of fresh weight of lettuce was 682.27 g/m2, related to the mutual effects of humic acid treatments of 1500 mg/l and salinity stress. The application of humic acid and increasing its concentration decreased the activity of catalase enzyme and ascorbate peroxidase enzyme. Salt stress increased the activity of catalase enzyme and ascorbate peroxidase enzyme. The lowest activity of catalase enzyme (0.004 µmole FW/min) and ascorbate peroxidase enzyme (0.41µmol H2O2 min-1.mg-1 protein), related to the interaction of humic acid 1500 mg/l and control of salinity stress. The highest activity of catalase enzyme (0.024 µmole FW/min) and ascorbate peroxidase enzyme(0.81 µmol H2O2 min-1.mg-1 protein) were observed in humic acid control under salt stress condition.

Comparing the energy of agricultural plants is one of the methods that can be used in prioritizing the cultivation of different agricultural plants in each region. In order to compare the energy input, output and global warming potential of rapeseed and rainfed barley fields in Golestan province (Aqqla city), an experiment was conducted in the fall of 2019. For this purpose, through interviews with different farmers (37 and 21 farmers for rainfed barley and rainfed rapeseed, respectively, by filling out questionnaires in Aqqala city) to collect the required data of machines and consumables including Seeds, fertilizers, fuel and pesticides were used in two crops. After that, the required data were calculated in three sections: fuel consumption, fuel consumption and global warming potential due to the emission of greenhouse gases based on CO2. The highest percentage of direct input energy in rapeseed and rainfed barley fields was related to fuel consumption with 39.3 and 46.8 percent, respectively. The highest and lowest global warming potential was obtained from rapeseed and rainfed barley fields (1492 and 1.739 kg CO2 per hec, respectively). Also, in both products, the lowest amount of greenhouse gas production related to potassium fertilizer was 26.3 kg CO2 equivalent for rainfed rapeseed and 1.13 for rainfed barley. In both products, fuel consumption and fertilizer constitute the highest energy consumption and greenhouse gas production. The use of tools that reduce fuel consumption is recommended, and the necessity of investigating and researching rotation crops and using plants capable of fixing nitrogen is revealed.

In order to investigate the effect of nitrogen and phosphorus biological fertilizers on the yield of red beans, a factorial experiment was conducted in the form of a randomized complete block design with replication in the agricultural year of 2012 in a farm located in Bravar region of Borojar city. The experimental treatments included the use of biological nitrogen fertilizers including  nitroxin and 2 special bean rhizobium fertilizers  nitro cara fertilizer  (control sample) was used. Phosphorous fertilizers including:  bio superphosphate  fertilizing 2.without fertilizer (control sample) were investigated. Based on the results of this research, it was determined that the mutual effect of the use of nitrogen and phosphorus biological fertilizers on plant height traits, the number of seeds per pod, as well as the simple effect of phosphorus biological fertilizer on the characteristics of the weight of one thousand seeds, the number of pods per plant, and the simple effect of nitrogen biological fertilizer on the characteristics of economic performance was significant at the 1% probability level. Also, the simple effect of phosphorus fertilizer was significant. Economic yield is significant at the 5% probability level. The simple effect of nitrogen and phosphorus and the mutual effects of fertilizers on the attributes of thousand-seed weight and the number of pods per plant are insignificant. The results of the comparison table of Duncan's mean show that in terms of grain yield, the highest yield of red bean seeds is related to fertilizer. Biological nitrogen level  (Nitro kara) is 634.2 kg/h, and also the highest number of seeds per pod and the number of pods per plant are related to biological nitrogen fertilizer level  (Nitro kara) is 7 seeds per pod and 19.33 pods per plant, respectively. In total, Nitro kara biological fertilizer had the most positive effect on the performance and performance components of beans, which can be used to prevent excessive use of chemical fertilizers and environmental problems caused by their use, while producing good and stable products.