نشریه زراعت دیم ایران
سال دهم شماره 1 (بهار و تابستان 1400)

In order to investigate the effect of plant growth promoting rhizobacteria on grain yield and gas exchange of new dryland wheat cultivars, a factorial field experiment was counducted in a randomized complete block design with three replications on the farms of Sarablah Agricultural Research Center in the cropping seson during 2019-2020. Experimental treatments include different wheat cultivars (Sardari, Karim, Koohdasht and Rijo) and treatment of different fertilizer sources including: control (without fertilizer source), 50% N fertilizer, Azospirillum + 50% N fertilizer, Azetobacter + 50% N fertilizer, Azospirillum + Azetobacter + 50% N fertilizer and 100% N fertilizer. The results of this study showed that the interaction of cultivar×different fertilizer sources was significant on grain yield, yield components as well as gas exchanges of dryland wheat. the highest grains.spike-1 (80%), 1000-grain weight (33.3%), grain yield (86.3%), biological yield (79.9%), photosynthesis rate (81.8%), transpiration rate (74.8%), mesophilic conductance (85%), photosynthetic water use efficiency (42.3%) was obtained from the interaction of Rijo× Azospirillum+Azetobacter +50% N fertilizer and the lowest value of these traits was related to the interaction between Sardari cultivar control treatment (without fertilizer source).

Quinoa was considered for preliminary evaluation in early spring rainfed conditions in two warm and humid and temperate climates (Sararud Kermanshah). Eleven quinoa Lines with different maturity periods was cultivated based on randomized complete block design with three replications in the Iraqi Mahaleh Research Station of Gorgan and the Research Station of the Deputy of dryland Agriculture of Sararud (Kermanshah), in 2016-2017 cropping season. The results of mean comparison in Gorgan showed that the highest seed yield (SY) was related to NSRCQ1 and NSRCQ9 lines and then NSRCQ6, which had a significant difference with NSRCQ9. The results of correlation and the main components analysis showed that the thousand seed weight (TSW) had the greatest effect on SY. The results of cluster analysis showed that the NSRCQ1 and NSRCQ9 with 194 and 209 g m-2SY and 2.5 and 2.6 gwere superior. The results of mean comparison in Sararud showed the lines yield were between 31 and 37 g m-2 and NSRCQ10 with 37 g m-2 and 1.3 ghad highest SY and TSW.In Sararud slow growth of the early stages due to the cold temperature, heat and drought at the end of the season reduced the yield and TSW and necessity for supplemental irrigation. Lack of synchronicityof heat and humidity regime of the studied lines reduced the SY in Sararud compared to Gorgan. In general, in Gorgan and areas with similar climate condition early spring cultivation with early and insensitive cultivars of quinoa to photoperiod are possible.

To investigating the effect of superabsorbent polymer application on agronomic properties and forage yield of alfalfa under different moisture conditions, a split plots experiment was conducted based on a randomized complete block design with three replicas, in the year 2014-2017. Treatments were irrigation in three levels including included at three levels (no irrigation, water deficit (supplemental) and normal) and super absorbents including 0, 50,100, and 150 Kg/h.There was a significant difference between irrigation treatments in terms of the effect on all studied traits except for the leaf area index, while the difference between superabsorbent levels was significant on all studied traits. Results showed that no irrigation treatment decreased the number of leaves per stem, leaf weight, and leaf area index and by 21.81, 21.18 and 10.86 percent compared with normal irrigation, also the application of 150 kg ha-1 superabsorbent increased the amount of these traits by 22.09 and 18.96 and 17.09 percent respectively. In the present study, water deficit (supplemental) treatment with the application of 150 kg/ha had the highest plant height (73.05 cm), dry forage yield (0.31kg/m2), and crude percent protein (14.58%). The results also showed that the difference between the treatment applications of 100 and 150 kg / ha of superabsorbent in rainfed conditions with control treatment (not using superabsorbent) in normal irrigation conditions was not significant in terms of dry forage yield. Therefore, the use of superabsorbent in different humidity conditions can be a suitable solution to increase the quantitative and qualitative of forage yield in alfalfa

Twelve cultivars/ breeding lines were tested on field's farms at two sites, Delfan and Khorramabad (Imanabad region), to identify the best barley genotypes and to determine characteristics related to improving grain yield, during the 2017-2018 cropping season. The mean grain yield of genotypes in the Imanabad region ranged from 2888 kg/ha (for breeding line G5) to 4500 kg/ha (Qaflan cultivar). In the Delfan region, cultivars, Qaflan and Sahand, and two breeding lines, G7 and G11, increased yields by 11, 8, 10 and 8 percent compared to control cultivar, Abidar, respectively. The results of correlation analysis and GT-biplot showed the high correlation between grain yield with BY and then DM at two sites. Therefore, BY and DH can be considered efficient selection indicators for the identification of genotypes with high performance in barley breeding under rainfed conditions. Correlation findings also showed that the positive or negative correlation between yield components, including KNS and TKW, and grain yield depended on the environment. Based on the results of this study, the Qaflan cultivar with the highest grain yield (4594 kg/ha) and earliness can be recommended in land-dry, cold and temperate-cold regions

This experiment was conducted in strip split plot based on randomized complete block design (RCBD) with three replications in three cropping seasons 2014-17 in Three regions in Kermanshah province (Mahidasht in first year, Sarabnilofar in second year and Sararood in third year). Plant residual was horizontal factor with three levels: No residual, 1 and 2 ton.ha-1 plant residues, tillage system contains three levels No-tillage (direct planting), Minimum tillage (by chisel plow) and conventional tillage (by Moldboard plow) was main plot and phosphorous fertilizer with two levels (no fertilizer and 30kg.ha-1 P2O5) was sub plot that were vertical factors. Results showed that chickpea grain yield increased by increasing plant residues so grain yield of one and two tone.ha-1 of plant residues treatments had higher grain yield than no residual treatment. Effect of tillage system on chickpea grain yield was different in years with different climatically conditions. Mean comparison of phosphorous fertilizer levels showed grain yield of chickpea in apply 30kg.ha-1 P2O5 was higher than no application of phosphorous. Economic analysis showed the highest benefit to cost ratio (3.82) obtained by minimum tillage (chisel) with 1 ton.ha-1 plant residue and no application of phosphorous treatment.

Evaluating of the chickpea genotypes under different environmental conditions would be useful to identify genotypes with stable and high yield potential. The purpose of this study was to identify high yielding genotypes, cold tolerant and stable types for sowing in cold regions of Iran. The experiment was conducted using thirteen chickpea genotypes in randomized complete block design with four replications in four cold regions of Iran including Maragheh, Kurdistan, Urmia, and Hamedan during three successive cropping seasons (2017-2020) in autumn planting under dryland conditions. Among the chickpea genotypes, the highest and lowest average seed yield obtained in G1 (893 kg.ha-1) and G9 (744 kg.ha-1), genotypes, respectively. The contribution of environments (E), genotypes (G), and genotype × environment interaction (GEI) to the total variation in seed yield was 68.4%, 1.21% and 10.30%, respectively. According to singular value partitioning, the first two principal components explained PC1=42.86% and PC2=27.88% of total variations in data of seed yield. On the basis of GGE biplots, G1, G3 and G8 had high seed yield and yield stability as compared to the other genotypes. In conclusion , G1, G3 and G8 with high mean yield and stability performance can be used in selection/ recommendation process of cultivar.

The effect of tillage methods on the quantitative and qualitative yield of rainfed wheat cultivars in different seed rates under a fallow-wheat rotation system during three cropping seasons (2017-1999 to 2009-2010) at Saral Research Station was studied. A strip split plot design based on RCBD with three replications was used. Conventional Tillage, CT(tillage with moldboard in spring followed by disk harrow in summer), Minimum Tillage, MT(Stubble cultivator after harvesting in summer) and No Tillage, NT(direct planting without soil disturbance) as horizontal, rainfed wheat cultivars(Azar 2, Baran and Sardari) as vertical and different seed rates(300, 350, 400 and 450 seeds per square meter) were considered as subplots. The results showed CT compares with MT and NT, increased grain yield by 22% and 21%, respectively. Wheat cultivars did not affect grain yield, significantly. The seed rate of 350 grain per square meter produced more grain yield than other treatments. Apart from the interaction of year × tillage, none of the interactions were significant. There was no significant difference between cultivars and seed rate in terms of protein percentage, but the effect of tillage was significant at 1% level, so that the highest and the lowest amount of grain protein was found in CT(12.72%) and MT (11.59%), respectively. The response of wheat cultivars to seed rate and tillage in the wheat-fallow system was not significantly differed. Due to the long fallow period and the reduction of residues on the soil surface followed by sharp decline in yield, conservation tillage is not recommended.