نشریه فیزیولوژی گیاهان زراعی
پیاپی 52 (زمستان 1400)

Considering the effect of temperature and day length on maize grain yield, knowing the appropriate planting date of different maize hybrids is necessary. In order to investigate the response of different groups of maize hybrids to planting date in Hamedan region, three early maturing hybrids (KSC201, KSC260 and KSC400), two medium maturing hybrids (KSC647 and BC678) and two late maturing hybrids (KSC703 and KSC704) were planted in Four planting dates (30 April, 22 May, 10 June and 1 July) into random plots based on a randomized complete block design during 2017 and 2018 at Ekbatan Research Station of the Agricultural and Natural Resources Research Center of Hamadan Province. Planting dates were placed in main plots and hybrids in sub plots. The highest grain yield of hybrids was observed on the second planting date and KSC703, KSC704, BC678 and KSC647 hybrids with grain yield of 18271, 18066, 17068 and 16491 kg.ha-1, respectively, were significantly superior to KSC400, KSC260 and KSC201 hybrids with grain yield of 13557, 1260 and 12291 kg.ha-1, respectively. With delay in planting time (third planting date), grain yield of all hybrids decreased and despite the reduction of planting to flowering period, other phenological characteristics include: grain filling period, day to grain physiological maturity and day to grain moisture of 20% (suitable time for mechanized harvesting) increased. At the last planting date (1 July), late maturing hybrids did not reach the physiological maturity stage of grain, and medium maturing hybrids were not able to reach the appropriate harvest moisture, while early maturing hybrids could be harvested before facing the severe autumn cold and among them, KSC400 showed the highest grain yield with 11110 kg.ha-1. In general, in case of delaying the planting time to 22 June-6 July in region such as Hamedan, planting early maize hybrids (especially KSC400 hybrid) is recommended due to desirable grain yield and the possibility of timely preparation of land for the next crop.

This study was performed to investigate the effect of foliar application of salicylic acid and application of biofertilizers on yield and physiological characteristics of white beans under drought stress. The experiment was conducted during two years of 2018 and 2019 in Boroujerd Agricultural and Natural Resources Research Campus located in Lorestan province as a split factorial split in a randomized complete block design with four replications. In the main plots, drought stress treatment was at the two levels of presence and absence of drought stress in the form of defecit-irrigation. Also, in the subplots, two factors of biofertilizer and salicylic acid were factorial. Phosphorus biofertilizer treatment included three levels of control and application of Bacillus and Pseudomonas bacteria. Salicylic acid treatment also included foliar application of salicylic acid at levels of 0, 1 and 2 mM. The results of combined analysis showed the effect of year treatment, drought stress, salicylic acid, biofertilizers and also their interaction on physiological characteristics such as chlorophyll a, b, total, relative leaf water content, soluble protein and catalase and superoxide dismutase enzymes. Drought stress increased the proline content and decreased soluble protein content and relative leaf water content, while the use of salicylic acid and biofertilizers under drought stress conditions improved these traits. The activity of superoxide dismutase was significantly increased by the use of salicylic acid and biofertilizers. Drought stress decreased grain yield and although in both stress and lack of stress application of biofertilizers increased grain yield, but the highest grain yield of 2937 kg / ha was obtained in Pseudomonas application treatment. Overall, the results of this study showed that under drought stress conditions that the physiological characteristics of the plant are not in favorable conditions caused a 55% reduction in grain yield. Application of salicylic acid improved the physiological properties and increased the antioxidant activity of the plant, which eventually increased the grain yield by improving these properties. The application of Bacillus and Pseudomonas biofertilizers also improved the physiological characteristics of the plant and subsequently increased the grain yield of white beans and increased the grain yield by 14% and 24%, respectively.

In order to investigate the effect of planting date and cultivar on yield components and physiological traits, split plot was performed in a randomized complete block design with three replications in 2020-2021years at the University of Lorestan. The main factor consisted of four cultivation dates 6 October, 21 October, 5 November, 21 November and the sub-agent of the figure, including Chamran, Sirvan, Mihan. The results of analysis of variance showed that simple effect of planting date on all traits in one percentage probability level and simple effects of cultivar on grain yield, harvest index, number of spikes per square meter, 1000 grain weight and dry matter remobilization at the probability level of a Percent was significant. Planting date on 6 October due to early culture and developmental stages with lower temperatures of plant tolerance and planting date 21 November due to delay during planting and limiting the production of tillers per plant and, as a result of reducing the number of spikes per square meter, grain yield decreased. The highest grain yield with 6976 kg ha-1 was related to the planting date of 5 November and the Mihan cultivar. In general, the history of cultivation, while increasing the optimal conditions for wheat cultivars, provide growth and physiological characteristics of the plant, including photosynthetic components, provide favorable conditions for the more favorable growth of the plant and ultimately increase the event. In the recent study, the Date of Planting 5 November and Mihan cultivar is recommended as the best planting date and cultivar for Khorramabad region and similar climate areas.

In order to evaluate the effect of chemical and biological fertilizers on crop and physiological characteristics of wheat, pearl cultivar was applied in experimental form in the form of complete randomized randomized blocks with three replications in Nokandeh city of Golestan province. Experimental factors include nitrogen supply sources at four levels of nitrogen (12 g/100 kg seed), Azospirillum (12 g/100 kg seed), urea (200 kg/ ha-1) and an equal combination of three sources (33% Azotobacter + 33% Azospirillum + 33% urea) and phosphorus-supplying sources at the level of three levels of triple superphosphate (100 kg / ha), fertile phosphate 2 (12g/100 kg seed) and equal combination of two sources (50% triple superphosphate + 50% fertile phosphate 2)) Was with the control.  The results of analysis of variance showed that nitrogen and biological fertilizers had a significant effect on all traits except the weight of one thousand seeds at the level of one percent probability. The results showed that the highest plant height, biological yield, spike length, number of seeds per spike, grain yield, flowering and care protein, chlorophyll b and total fertilizer treatment combined the three sources of nitrogen supply (33% Azotobacter + 33% of Azospirillum + 33% Urea). High levels of leaf area index, spike and chlorophyll a were obtained with Azotobacter treatment. In summary, the results of this study showed that using the right combination of biofertilizers and nitrogen fertilizers can reduce the use of chemical fertilizers and therefore be consistent with agricultural goals.

Most bean cultivated lands are in areas that facing water deficit during the growing season. In order to investigate the effect of irrigation period and nitrogen fertilizer on yield, yield components and water use efficiency of red bean (cv. D-81083), an experiment was conducted as a split-plot based on a randomized complete block design with four replications at Boroujerd Agricultural Research Station (Lorestan) during two crop years. The main-plots were included four irrigation times after 36 (I1), 54 (I2), 72 (I3) and 90 (I4) mm of cumulative evaporation from class A evaporation pan and sub-plots were included the amounts and method of nitrogen fertilizer consumption including N1: without the use of nitrogen fertilizer (urea) or control, N2: consumption of 50 kg/ha of urea fertilizer at planting, and N3: consumption of 50 kg/ha of urea fertilizer at planting + 50 kg/ha of urea fertilizer at the beginning of the flowering stage. The results showed that, the highest number of pods per plant (18.3 pods), number of grains per pod (6.13 grains), grain yield (2538.8 kg/ha), biomass (5330.8 kg/ha) and water use efficiency (0.376 kg/m3) were achieved from I2N2 treatment. In the treatment of I4 application of nitrogen fertilizer didn’t have much effect on the traits. In general, the irrigation period can be planted from the beginning of sowing to before flowering stage every 7 to 8 days and after this period arranged for 5-6 days. Also, it is recommended to consumption of 50 kg/ha of nitrogen fertilizer at planting to stimulate early root growth until they sufficiently infected with rhizobium bacteria.

In order to evaluate the effect of methanol foliar application on yield and physiological traits of cowpea under water  deficit the experiments were carried out in the research farm of Safiabad Agricultural and Natural Resources, Research and Education (Dezful) along two crop years 2016-17 and 2017-18. The experiment was performed as split split plots in a randomized complete block design with three replications. The studied treatments included water stress at four levels (25, 50, 75 and 100% water supply of the plant) as the main plot, three levels of methanol foliar application (control, 10 and 20% by volume) as a secondary factor and two bean genotypes (1057 line omidbakhsh and Mashhad) were as a sub-factor. The results showed that the application of different levels of water stress reduces the relative water content of leaves, the amount of chlorophylls and carotenoids and increases the amount of electrolyte leakage and proline content. On the other hand, foliar application of different levels of methanol were able to reduce greatly the destructive effects of water  deficit so that the relative water content of leaf increased from 69% in control to 73% in 20% volumetric methanol. Also, 1057 line showed better conditions than Mashhad cultivar for all measured physiological traits and was better in ability to tolerate water deficit. In addition, harvest index and biological yield were reduced under water deficit condition, but grain yield at 50% water supply of the plant showed the highest value due to the earlier entry of the plant in this stress to the flowering stage and longer this stage compared to 75% and 100% water supply of the plant. Also, methanol foliar application was able to eliminate the destructive effects of water deficit on the measured yield traits.