نشریه زراعت دیم ایران
سال هشتم شماره 2 (پاییز و زمستان 1398)

In order to investigate the effect of growth promoting bacteria on yield and yield components and some nutrients of durum wheat, an experiment was carried out at the research farm of Ilam University in 2015-2016. An experiment was carried out as a factorial based on a randomized complete block design with three replications. Experimental factors included three levels of growth stimulating bacteria (Azospirillum brasilense, Azotobacter chroococcum and non-inoculation), moisture conditions in two levels (supplementary irrigation and rainfed) and two durum wheat cultivars (Saji and Dehdasht). The results showed that supplementary irrigation increased yield and yield components and nutrients content of durum. The effect of Bio-fertilizer on yield and yield components and nutrients of durum wheat was significant but Azospirilum was superior to Azotobacter. Finally, the highest concentrations of nitrogen (20.71 %), phosphorus (13.1 %), potash (3.7 %), and maximum grain yield (2923 kg.ha-1), biological yield (8566 kg.ha-1) and harvest index (42.39 %) were obtained from two cultivars under irrigation conditions in inoculation with growth promoting bacteria.

Early flowering and shorter vegetative phase can be very important for wheat production in terminal drought stress condition. Earliness can minimize exposure to dehydration during the sensitive periods such as flowering and grain filling. In this research, earliness was transferred from Excalibur (donor parent) to Roshan, Mahdavi and Kalheydari (recurrent parents) cultivars using backcross method. Several back-crosses for developing BC3F2 generation were done during 2011 to 2018 at the research field of Shahid Bahonar University of Kerman. Around 1000 filial of each population were evaluated for heading time and 20 of latest heading and earliest heading filial were selected. Analysis of variance revealed that interaction of genetic background and earliness was highly significant for days to heading. This finding showed the effect of modifier genes of each background on earliness genes that transferred from Excalibur. The most response to selection for earliness was found in Roshan, followed by Kalheydari and Mahdavi backgrounds, respectively. According to results, earliness significantly improved 1000-grain weight. In addition, negative correlation between days to heading and 1000-grain weight (-0.43) confirmed the above results. Roshan, Kalheydari and Mahdavi are drought tolerant Iranian cultivars. Meanwhile, these cultivars are semi late flowering. In the present research, number of days to heading was significantly decreased in all three backgrounds. According to the present results, it can be concluded that breeding for early heading not only save water consumption, but also improved 1000-grain weight even under well-watered condition.

The most of barley cultivation areas in Iran are located in cold, arid and semi-arid regions therefor, achiving to high yielding cultivars with appropriate adaptation to various climatic conditions and drought tolerance is necessary. For this purpose, some effective morphological traits on grain yield and drought tolerance were studied in 108 barley genotypes. The experiment conducted in alpha lattice design with two replications in two rainfed and irrigation conditions at Dryland Agricultural Research Institute (DARI) (Maragheh station) during 2015-2016. Analysis of variance showed there were significantly differences inall of the traits in rainfed and supplementary irrigation conditions. The most important traits affecting grain yield under rainfed conditions were thousand kernel weight, NDVI in booting stage, stem width and main spike length, and in supplementary irrigation conditions were thousand kernel weight, NDVI in milk development stage and main spike length. Drought tolerance indices also evaluated and MP, GMP, STI, YI, and SSPI indices had the highest correlation with grain yield in both conditions. Based on these indices, 25 drought tolerant genotypes were identified.

Barley has a special place in agriculture in terms of adaptation to different climatic conditions, valuable features in human nutrition, livestock and importance in the food industry.  The uses of external germplasm in breeding programs for direct use (after stability tests) or in producing hybrids are of high importance. For this purpose, 44 Iranian and European barley cultivars in a randomized complete block design with three replications at the experimental farm of Agricultural Faculty of Razi University, were evaluated under rainfed condition during the 2013-2014growing season. Important agronomic traits such as grain yield, biomass yield, number of spikes per m2, number of grains per spike, 1000-grain weight, and physiological traits including relative water content, membrane degradation or stability, SPAD, stomatal conductance and traits related to seed malt were determined. Analysis of variance showed significant difference among the cultivars for most of the traits at 1% probability level. Group comparisons showed unique characteristics of Iranian and European cultivars, so that Iranian cultivars had the highest values for hectolite weight, thousand kernels weight, spike density, grain length and grain length/ grain width, while the European cultivar had the highest potential for harvest index, number of spikes per square meter, spike length and awn length. Compared to European cultivar, the relative water content of leaves and degree of membrane damage and SPAD-reading in seedling stage were higher in Iranian cultivars. For the optimal use of these cultivars in plant breeding projects, parents can be selected at a reasonable distance based on desired traits.

In order to investigate the effect of plant density and phosphorus resources on yield and yield components of black cumin (Nigella sativa L.), medicinal plant, at dryland conditions, a split-plot experiment based on randomized complete block design with three replications was conducted at Soil and Water Conservation Research Center, University of Tehran, located in kouhin dryland farms in Qazvin Province, Iran in 2016-2017. Phosphorus resources were chemical Phosphorus (150 kg/ha di-ammonium phosphate or control) (p1), 50% chemical Phosphorus + 50% biological Phosphorus (p2), biological Phosphorus Barvar II® alone (p3) and plant density levels were (d1)20, (d2) 30 and (d3)40 plants/m2. Results showed that interaction effect between plant density and phosphorus resource were significant on number of capsule per plant, number of grain per capsule, number of grain per plant, grain yield, biological yield and harvest index. Also number of grain per carpels was affected by phosphorus treatment, but the number of carpels per capsule and 1000 grain weight were not significant. The highest grain yield (206.25 kg/ha) was obtained from biological Phosphorus fertilizer application (P3) with 40 plants/m2 plant density and the lowest grain yield (42.34 kg/ha) was recorded for control (P1) treatment with 40 plants/m2 plant density. So, application of biological phosphorus and high plant density (40 plant/m2) had the highest grain yield however, chemical phosphorus (control) in high plant density produced the lowest grain yield.

The objective of this study is the determination of adoption indices and measurement profitability by Investment Rate of Return (IRR) and economic surplus due to the planting of Dehdasht variety. Requiered data were collected from institutes, organizations, Agricultural Research and Education and Natural Resource Centers of targeted provinces by questionnaire in during 2010-2017. In this research,the adoption analysis indices and economic surplus criteria were used. Based on Ministry of Jihad-Agriculture, means of adoption degree of Dehdasht variety in formal seed was estimated 1.3 percent during 2015-2017. Based on the price of durum wheat during study years, means of the change of economic surplus and net present value (NPV) of activity were estimated 602 and 1014 billion Iranian rials.The Investment Rate of Return (IRR) of Dehdasht variety was estimated more than discount rate. In generally, breeding program of Dehdasht variety is economic. It is suggested that in future research planning, researcher select breeding lines through breeding programs and introduce to farmers that not only has high yielding potential compared to the check variety and adapted to the climate but also thay have good resistance to biotic and abiotic stresses.

In order to evaluate the productivity potential of some barley varieties and promising lines under no-till condition an experiment was conducted in cold (Sonqor) and warm (Sarpol-e Zahab) dryland regions of Kermanshah province during 2017-18 cropping season. In the cold condition, seven winter genotypes and in the semi-warm condition seven spring genotypes were evaluated for grain yield and some agro-physiological traits. The results of ANOVA in the cold condition indicated significant differences (P<1%) days to heading, chlorophyll content (SPAD), days to physiological maturity and grain yield. In the semi-warm condition the genotypes were significantly differed (P<5%) for normalized difference vegetation index (NDVI) and canopy temperature (CT). In cold condition, grain yield of genotypes varied from 2818 (Sahand variety) to 5864 kgha-1 (belong to breeding line G4). In the semi-warm condition, due to severe drought and terminal heat stress the grain yield of genotypes varied from 208 (Faraz cultivar) to 367 kgha-1 (local variety). Based on genotype × trait biplot analysis, in cold region genotypes G4 and G6 was the best for grain yield (YLD) with 1000-kernel weight (TKW), number of grain per spike (NGPS) and days to heading; and in semi-warm condition genotype G3 had the best results for both YLD and TKW. The profiles of trait associations were relatively different in cold and semi-warm conditions. The positive correlations of NGPS and TKW with grain yield showing the importance of these traits to enhance yield productivity under dryland conditions.