shirali kohkan

This study was conducted using the emergy analysis approach in wheat production systems in order to plan and manage the major challenges facing the Sistan region's wheat production. All inputs for wheat production, the most important crop in the region, were assessed in this study. These inputs include renewable inputs, such as sunlight, wind, and rain; nonrenewable inputs, such as soil erosion; and purchased inputs and services, such as machinery, fossil fuels, electricity, labor, nitrogen, potassium, phosphorus, and chemical fertilizers. According to the results of the study, the total emergy production of wheat was 1.061016 sej ha-1. The irrigation water consumed the most energy at 28.96%, followed by nitrogen and phosphorus fertilizers at 20.75 and 16.5%, respectively. The emergy yield ratio index was 1.41, the emergy investment ratio index was 2.4, the environmental loading ratio was 2.41, and the emergy sustainability index was 0.585, which indicates the average sustainability and environmental load of this system relative to other researchers' reports. By increasing input efficiency by optimizing the consumption of irrigation water, nitrogen fertilizer, and phosphorus fertilizer, this production system can be made more sustainable and less taxing on the environment.

The aim of this study was to select of the barley superior lines based on some of morpho-phenological traits using various indices based on REML/BLUP model and as well as the SIIG index and comparison of these indices. A set of 17 promising lines along two checks were evaluated in a RCBD with three replications at three research stations including Zabol, Darab, and Gonbad Kavous during the 2020-2021 cropping year. The results showed that there was a significant difference between the test regions and genotypes in terms of all measured traits. The results obtained by REML model indicated that the highest and lowest heritability values were related to 1000-grain weight and grain filling period, respectively. The MTSI index identified lines G9, G2 and G3 as superior lines, while the FAI-BLUP index identified G13, G11 and G3 as the best lines based on their traits and grain yield. Based on the SIIG index, lines G7, G2, G8 and G17 were identified as the most superior lines. In general, by comparing the results obtained from different indices, selected lines with SIIG index due to high grain yield and high 1000-grain weight were chosen as selected genotypes for complementary tests. In addition, the selected genotypes using FAI-BLUP and MGIDI indices were early maturity and had a high 1000-grain weight, but their grain yield were lower than both checks of experiment.

For assessment of genotype × environment (G × E) interaction effects and determination of the most sustainable genotypes 20 barely lines were analyzed in at eight different experimental field stations. The experiments were performed based on Randomized Complete Block Design (RCBD) with three replicates. Grain yield was obtained and the results of the combined analysis of variance revealed genotype, environment and genotype × environment interaction effects were highly significant. Genotypes yield means showed that the G1, G13 and G4 genotypes had the highest grain yield. AMMI model analysis was used to determine the magnitude and significance of the genotype × environments interactions and divided G×E interaction to two principle components that explained 46/48% and 19/52% of interaction effects respectively and residuals. Based on biplot and AMMI analysis G, G genotypes were selected as candidate's lines with both best performance and grain yield sustainability. The environment E5 with high IPCA 1 and low IPCA 2 had the highest effect on determination of genotypes. The genotype G20 was selected as candidate line with high grain yield performance and stability.

Irrigated barley is grown on about 50,000 hectares in the warm agro-climate zone in the south of Iran. The average grain yield of barley in these areas is 2,000 Kg/ha. Wide adaptability and high grain yield stability are important assets for barley varieties to be grown by farmers. Zahak barley cultivar was initially selected from international barley germplasm received from CYMMIT and based on its high grain yield and yield stability as well as its desirable agronomic characteristics in the experiments, which were conducted from 1996 to 2010, was released for growing in the warm agro-climate zone in the south of Iran. The average grain yield of Zahak is 4846 kg/ha that is 524 kg/ha higher than grain yield recorded for Nimrooz variety, a widely-grown barley variety in the warm regions of Iran. Zahak is six-rowed spring barley with a medium plant height (85-90 cm). The average of days from sowing to maturity for Zahak is 138 days but it has a longer grain filling period comparing to the older barley cultivars in southern parts of Iran such as Jonoob and Nimrooz. Possessing fertile florets at the lower spikelets of the mature spike is other important characteristic of Zahak. In addition, it exhibits lodging resistance, non-shattering rachis as well as semi-resistant infection responses to powdery mildew and spot blotch diseases in the most of warm agro-climate zone in the south of Iran.