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IntroductionLegumes are the most economically important food source for humans due to their protein richness, especially in developing and underdeveloped countries. Chickpea yield in spring-planting under dryland cropping decreases due to increasing temperature and day length and the occurrence of end-season drought and exposure to important pest's activity. In autumn-planting, early flowering, escaping from pests and optimal use of annual rainfall help to significantly increase in grain yield. Increasing the growth period during autumn planting has been found to result in taller plant height, making mechanical harvesting more feasible. The success of a plant breeding program relies on implementing a suitable selection design that takes into account both correlated and non-correlated relationships. Recently, a significant positive correlation has been observed between grain yield and several traits such as the number of pods, number of seeds, 100-kernel weight, and harvest index in chickpea. These traits were also found to have a direct and significant effect on chickpea grain yield. Additionally, there was a high direct effect observed for pod number, number of seeds, 100-kernel weight, and single-seed weight on chickpea grain yield. Materials and MethodsThis research was conducted on 112 chickpea genotypes in dryland spring-planting (non-cold stress condition) and autumn-planting (cold stress) based on augmented design in Dryland Agricultural Research Institute located in Maragheh. Total pods number, number of empty pods, number of tow-seed pods, plant height, first pod height from soil level, number of pods with one seed, days to maturity initiation, days to 90% maturity, 100-kernel weight, pod diameter, pod length, biomass, harvest index, fertility percent and single-plant yield were meassured. The correlation analysis, stepwise regression and path analysis, and principal component analysis were used for identifying the relationships among agro-morphological traits. Results and DiscussionIn autumn-planting condition grain yield positively correlated with all traits except days to 90% maturity, but in spring-planting condition the correlation between grain yield and first pod height, days to maturity initiation, days to 90% maturity, 100-kernel weight, pod diameter and pod length were not significant. In spring-planting, 100-kernel weight and total pods number were negatively correlated. In both spring and autumn-planting, the 100-kernel weight showed a significant positive correlation with pod diameter and pod length. This indicates that genotypes with larger pods also tend to have larger seeds. Furthermore, in autumn-planting, there was a significant positive correlation between pod diameter, pod length, and grain yield. However, these correlations were not significant in spring-planting. Stepwise regression analysis was performed to assess the factors influencing grain yield in both planting conditions. In spring-planting, the number of total pods, 100-kernel weight, fertility percent, and the number of two-seed pods were found to have direct and significant effects on grain yield. On the other hand, in autumn-planting, the number of total pods, pod length, number of empty pods, 100-kernel weight, and the number of two-seed pods were included in the final model as predictors of grain yield. These results suggest that these factors play a crucial role in determining grain yield in their respective planting conditions. In spring-planting, the genotypes 108, 63, 65 and 99 had the highest number of total pods, number of single pods, biomass and plant yield and genotypes 55, 76, 81, 82, 84, 85 and 88 had the highest weight of 100-kernel, pod length and pod diameter. In autumn-planting, the genotypes 87 and 22 had higher biomass and grain yield, genotypes 45 and 65 had higher total pods and number of single pods, genotype 89 had higher total pods and biomass and genotype 94 had higher total pods, number of single pods, biomass and yield. ConclusionCorrelation analysis results showed that in non cold stress condition (spring-planting), due to the short growth period, the significant relationship of most important agronomic traits with grain yield were not revealed and important components such as 100-kernel weight did not have enough opportunity to significantly affect grain yield. In spring-planting, total pods number had a high direct effect and correlation coefficient with grain yield, but the indirect effect of this trait through 100-kernel weight on grain yield was negative because increasing the number of total pods causes decreasing the kernel weight. In autumn-planting, despite the high direct effect of total pods number on grain yield, due to the indirect negative effect through the number of empty pods, the correlation coefficient of total pod number with grain yield was not very high. Finally in order to increase grain yield in chickpea genotypes in breeding programs it is recommended that under cold stress and non-stress conditions, selection should be based on the number of total pods per plant, which is a visible trait and easy to measure.

Key points Numerous biofilm forming PGPR reside in grass rhizospheres from arid grasslands. Drought tolerance of wheat is enhanced by bacterial inoculations. Wheat variety and the level of drought stress modify the plant’s response to the bacteria.

At percent, Zn stress tolerance using novel genetic resources is an important mitigation strategy for plant breeding. In this study, thirty-five durum wheat genotypes with different growth habits were evaluated under normal (non-stress) and Zn deficient stress during the 2014-15 cropping season. A total of ten Zn stress tolerance indices including stress tolerance index (STI), relative zinc-deficient index (RDI), yield index (YI), yield stability index (YSI), zinc-deficient resistance index (DI), abiotic tolerance index (ATI), stress susceptibility percentage index (SSPI), sensitive zinc-deficient index (SDI), and modified stress tolerance index (MSTI; K1STI and K2STI) were estimated. Results showed the significant influences of Zn stress on grain yield, as well as significant differences among genotypes for grain yield and the indices. The genotype G33 produced the highest grain yield under normal conditions by 0.854 g plant-1 while genotype G32 had the highest yield by 0.686 g plant-1 under Zn stress conditions. The genotypes G6, G13, G23, and G32 had less grain yield fluctuation, and G1, G21, and G29 genotypes had high grain yield fluctuation in two conditions. Cluster analysis showed that the genotypes, based on indices tended to four groups: tolerant, semi-tolerant, semi-sensitive, and sensitive genotypes, including 10, 17, 7, and 1 wheat genotypes, respectively. Grain yield was strongly positively correlated with STI, YI, DI, K1STI, and K2STI under two conditions, while negatively correlated grain yield with SSPI and SDI in Zn deficit stress condition, respectively. Using STI, YI, DI, K1STI, and K2STI, the genotypes G32, G33, and G19 were found to be the best genotypes with relatively high yield and suitable for both normal and Zn deficits stressed conditions. Therefore, they may be recommended to cultivate in Zn deficit prone regions of the world and also can be used in wheat breeding programs aimed at improving Zn stress tolerance.

DOR: 98.1000/2383-1251.1397.5. 129.10.2.1575.41 Extended Abstract Introduction: Weeds, as the most important biological stress, reduce the efficiency of water use, waste of food, shading and secretion of toxic substances, leads to a 10 to 100 percent reduction in crop yields. The first step of the weed control understands the biology and life cycle of the weed particularly seed Eco physiological characteristics. Dormancy in weed seeds, including Redroot Pigweed seeds, is common. So, due to the importance of dormancy breaking and germination studies of weed seeds, the present study was designed to identify the methods for dormancy breaking and the germination of Redroot Pigweed seeds. Materials and Methods: This research started in autumn 2013 by collecting Redroot Pigweed seeds from fields of Alajujeh village, Khoda Afrin County, East Azerbaijan Province, and then it was carried out at the Laboratory of the Faculty of Agriculture of the University of Maragheh in 2014 and 2015. For data analysis, the GenStat 12.1 program was used and the Duncan test was used at 5% probability level to compare the averages. Excel 2013 was also employed for drawing the diagrams. Results and discussion: Analysis of variance demonstrated that the effect of treatments on germination percentage and germination rate in Redroot Pigweed seeds at 1% probability level and the mean germination time at 5% probability level was significant. The results showed that among studied treatments, seeds holding for 18 months were most efficient seeds dormancy breaking at Redroot Pigweed. So that the highest germination percentage (92%), germination rate (29.18 seed/day) and lowest the mean germination (4.2 day) time were obtained in seeds holding treatment. Pre-chilling treatment also had significant effects in stimulating germination. As regards treatments of seed holding in low temperature and Pre-chilling accelerate the germination process and increase germination percentage, so, having precise information of these traits enables to study, a better management and control of this troublesome weed. Conclusions: In general, the results of this study show that among the treatments, holding seeds for 18 months at 6 ° C is the best method for solving Redroot Pigweed seeds weeds. Highlights: 1- Seed holding in low temperature and Pre-chilling accelerates the germination process. 2- Seed holding in low temperature increases germination percentage.

To evaluate the effects of Zn application on seed yield and some qualitative properties of wheat in a calcareous soil an experiment was carried out in factorial randomized complete block design (RCBD) with three replications at the Faculty of Agriculture, University of Maragheh, Iran, during 2014 growing season. The first factor consisted of four durum wheat genotypes and the second factor of levels two zinc sulfate application (control and foliar application of Zn on soil at stem elongation + seed filling stages). The results showed that application of zinc sulfate could increase biological and seed yields of RCOL genotype by 2 and 4 times compared to control respectively. The effects application of zinc sulfate on biological and seed yields of other genotypes were not significant. Based on the results obtained from this study the highest increase in seed weight was 20.7% in the RCOL genotype by Zn application. The highest reduction in phytic acid to zinc molar ratio was observed in Ege-88 genotype and this ratio was decreased by 52.2 percent in the control to 8.4% due to Zn application. This may indicate different responses of durum wheat genotypes to the zinc deficiency in the soil. The results also showed that the number of seed per spike was increased by 22.7 percent and phytic acid was decreased by 62.3 percent due to the application of zinc sulfate. Also, application of zinc sulfate increased Zn concentration in seed from 29.9 mg.kg-1 to 64.7 mg.kg-1 in control. In general, however, the application of zinc was not the reason of seed yield improvement of all genotypes studied but it improved seed yield qualities. It can be concluded that use of Zn is an appropriate method to improve the qualitative and quantitative traits of seed yield. To confirm these results other studies are needed.

Low zinc (Zn) availability and its absorption limit wheat production and quality of yield in calcareous soils. In order to identify Zn deficient stress tolerance in wheat, fifteen spring genotypes (Diyarbakir-81; Gediz-75; Svevo; Zenit; Amanos-97; Fuatbey-2000; Balcali-2000; Ceylan-95; Firat-93; Aydin-93; Ozbek; Artuklu; Akcakale-2000; Aday-19; and Ege-88) were evaluated under two conditions (normal and Zn deficient stress) in 2014-2015 growing season. This research was carried out in a factorial experiment based on randomized complete block design with three replications. Results of variance analysis showed that zinc-deficient stress had significant effects on plant height (PLH), spike length (SL), peduncle length (PedL), grains number per spike (GNPS), biomass yield (BY), and grain yield (GY). There were significant differences among genotypes for all studied traits, except spike length, BY, and GY. The interaction effects of genotypes and Zn deficient stress conditions were non-significant for all studied traits. The results showed that zinc-deficient stress caused 7.3, 9.5, 8.0, 20.8, 18.6, and 22.1% reduction in PLH, SL, PedL, GNPS, BY and GY, respectively. But had no significant effect on 1000-grain weight and harvest index. Results showed that ‘Gediz-75’ genotype with 0.62 g/plant and 14 grains had the highest GY and GNPS under two different conditions. But, ‘Aday-19’ genotype with 0.36 g/plant and 8.3 grains had the lowest GY and GNPS under two different conditions. The ‘Gediz-75’ genotype showed the highest STI (1.186), GMP (0.610), MP (0.621), and HARM (0.599) Zn stress indices. However, the ‘Aday-19’ genotype showed the lowest STI (0.399), GMP (0.354), MP (0.360), and HARM (0.347) Zn stress indices. With consideration, the correlation between indices and grain yield under zinc-deficient stress and non-stress, these indices (except the TOL, SSI, RDI, YSI, DI, ATI, and SSPI) were identified as the best stress indices for isolation and selection of tolerant genotypes.

Screening of cash crops to tolerate and grow under low levels of micronutrients is important issue in the plant breeding programs. Thus, the study screened the tolerance of 50 wheat genotypes to zinc (Zn) deficiency in the calcareous soil. The Zn treatment was carried out with application of 5 mg kg-1 (+Zn) and without (-Zn) to the collected soils with initial Zn extractable of 0.5 mg Zn kg-1 soil. The results revealed that the supplementary application significantly increased shoot dry matter, shoot Zn concentration and shoot Zn content compared to the without Zn application (control), but Zn utilization decreased under Zn application. There was considerable genetic variation in Zn efficiency (55 - 118 %), shoot Zn concentration (11.8 - 27.0 and 14.3 - 39.6 mg kg-1 DM under deficient and sufficient Zn, respectively), shoot Zn content (0.56 - 2.02 and 0.90 - 2.83 µg plant-1, under deficient and sufficient Zn, respectively) and Zn utilization efficiency (39 - 87.2 and 31.2 - 71.5 mg DM µg-1 Zn under deficient and sufficient Zn, respectively) within wheat genotypes. Cluster analysis based on Zn efficiency, and shoot dry matter at deficient and adequate Zn conditions classified the genotypes into four clusters. Over the two conditions, the most Zn-efficient and Zn-unefficient genotypes were ‘Ankara-98’ and ‘Altintoprak-98’ and ‘Pg"S’ and ‘Zarin’, respectively. Most durum genotypes had a greater Zn efficiency than modern bread wheat genotypes, therefore these genotypes could be effectively used to breed the new cultivars with high Zn efficiency for calcareous soils.

The effect of spent mushroom compost (SMC) on yield and yield components of wheat (cv. Azar2) under different moisture conditions was evaluated in pot experiment at Dry-land Agricultural Research Institute in 2010. Experiment arrangement was factorial based on complete randomized design with four replications. Treatments were SMC at three levels (0, 25 and 50 Mg.ha-1) and water deficit stress at three levels (-0.3 or field capacity, -5 and -10 bar). Some morphological, yield and yield components of wheat were determined. Results indicated that water stress had a negative and significant (P

Regarding negative effects of Cd on wheat growth, it seems that evaluation of wheat cultivars behaviors in response to Cd existence is necessary. In this regard, six different cultivars of wheat were selected and cultivated by aeroponic system. Then they were treated by 200 mM cadmium chloride for 14 days since they have reached 3 or 4 leaves stage. Finally, plants were sampled and morphological characteristics, parameters subjected to defense mechanisms as well as amount of accumulated Cd in tissues were evaluated. The results showed that cadmium accumulation in tissues significantly decreased root length and dry matter of root, shoot and whole plant. Cd accumulation also increased hydrogen peroxide amount in leaf cells of Kohdasht and Pishtase cultivars. However, lipid peroxidation was noticed in Izengeran cultivar as well as two previously mentioned cultivars. The reduced activities of glutathione S-transferase, catalase and ascorbate peroxidase enzymes are probably the main reasons of the lipid peroxidation increase in Kohdasht cultivar. However, there was no damage on membranes of Izengran and Pishtase cultivars, which indicates the balance between production and scavenging of damaging factors of these cultivars. Generally, it can be stated that available Cd in medium was adsorbed and accumulated in wheat leaves resulting in reduction in dry matter of different parts and whole seedling of wheat which is due to susebtability of different cultivars to Cd. However, there were no oxidative stresses in leaves of Gaskogen, Agosta and MV17 cultivars due to their better defense mechanisms.

Abiotic stresses such as cold, heat, and drought are the main causes of universal crop losses. Plants have generated adaptive responses which prevent them from oxidative damage caused by environmental stresses. The present research aimed to evaluate the effect of cold stress on lipid peroxidation and antioxidant enzyme activity in the leaves of eight cultivars / advanced lines of chickpea (Cicer arietinum L.). Three-week-old plantlets were subjected to cold stress (0°C) for 24 or 48 hours. Selected antioxidant enzyme activity and oxidative status of chickpea plantlets under cold stress were determined. In most genotypes, catalase and ascorbate peroxidase activities were increased and guaiacol peroxidase activity decreased under stress conditions but the activity of superoxide dismutase remained almost constant. Based on its ranking, Cicer arietinum ‘Saral’, a newly released cold-resistant Iranian chickpea cultivar, had the strongest, and FLIP 05-77C had the weakest antioxidative defense system under low temperature stress.

Salt stress as a major adverse factor can lower germination, ion toxicity, reduction in enzymatic and photosynthetic efficiency and other physiological disorders and ultimately lower crop productivity in salinity zones. As growth regulators are involved in altering growth processes in plants, it is possible that they might even reduce the detrimental effects of salinity by stimulating growth. But their physiological roles are not well known. In example, about the roles of IAA in salinity conditions are not similar viewpoints. For this purpose a factorial experiment based on completely randomized design was conducted with influence of foliar application of Indole-3-Acetic Acid (IAA) in farm on germination percent and seedling growth parameters of wheat (cv. Marvdasht) under different levels (0, 40, 80 and 120 mM) of NaCl salinity with 3 replications, during 2012 in the laboratory research of the Department of plant breading and agronomy, Faculty of Agriculture, Maragheh University in Maragheh state in Iran. The results of this study indicate, that salinity decreased the plumule, radicle and seedling length and plumule, radicle and seedling dry weight, seed germination and seedling vigor index, whereas increase in mean germination time and no signification plumule/radicle ratio observed in the cultivar tested. Also, application of IAA at cell division stage of grain growth caused significant increase in seedling growth parameters under different salinity levels. The interaction between application of IAA and salinity levels significantly affected final germination percentage. Highest final germination percentage was recorded with IAA with increasing salinity level from 0 up to 120 mM NaCl (98.3, 98.3, 96.7 and 100% without significant differences between them, respectively).

The effects of salt stress on the activity of antioxidative enzymes, some oxidative stress indices and Na+ and K+ content were studied in leaves of two durum wheat cultivars, Egypt 449 (salt-tolerant) and Syria 371 (salt-sensitive), grown under control (nutrient solution) or salt stress (nutrient solution containing 200 mM NaCl) conditions. Leaves of control and salt-stressed plants were harvested from 10 days old plants beyond salt treatment. The results showed significant increase for activities of antioxidant enzymes such as ascorbate peroxidase (APX) and guaiacol peroxidase (GPX), in Egypt 449 under salinity. At the same time, in cultivar Egypt 449, activity of SOD and CAT were not changed. Meanwhile, under salinity condition the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and GPX in cultivar Syria 371 was lower than control. There was no significant difference between salinity situation and control ones regarding APX activity. Salt stress elevated the amounts of malondialdehyde (MDA) in both cultivars. However, the increasing rate in Syria 371 was more than (four times) that of Egypt 449. Membrane stability index (MSI) of both cultivars negatively influenced by salinity. This negative impact on Syria 371 was highlighted than on Egypt 449. Hydrogen peroxide (H2O2) content of salinity faced Syria 371 was higher than control. Both cultivars displayed increasing and decreasing trend for Na+ and K+ content, respectively. Moreover, K+/Na+ ratio was decreased in both cultivars due to salinity. The studied parameters elucidated that salt resistance of Egypt 449 might be due to increased activity of antioxidant enzymes, low lipid peroxidation, assumingly lower changes in membrane stability index and avoidance of Na+ absorption.

Salt stress as a major adverse factor can lower leaf water potential, leading to reduced turgor and some other responses, and ultimately lower crop productivity in arid and semi arid zones. Wheat is one of the main crops occupying a large area in Iran, where salt stress is the most limiting factor. Clearly, plant salt stress tolerance requires the activation of complex metabolic activities including antioxidative pathways, especially reactive oxygen species (ROS) and scavenging systems within the cells which can contribute to continued growth under water stress. In the work reported in this paper, the seeds of two local wheat cultivars (Alvand and Sardari) were grown hydroponically. Seedlings were subjected to Hoagland's solution as control, and 50, 100, 150 and 200 mM NaCl for 10 days. As a result, SOD (superoxide dismutase) increased in Sardari with the increase of salt stress, while in the case of Alvand, SOD showed constant activity at all salt stress levels. Meanwhile, CAT and GR exhibited the same trends in the two cultivars of wheat in salt stress conditions. Results indicated that in the case of Sardari, the scavenging of ROS by the scavenging system especially by SOD, CAT and GR was done well and damage to membranes or MDA was controlled. But in the case of Alvand, damage to membranes increased with the rise of stress levels. It can be concluded that all three antioxidant enzymes were limiting factors for this cultivar. Also these reasons led to the sensitivity of Alvand to salt stress.

Studying the physiological role of nutrient elements has an unraveling capacity in understanding plant’s behavioral pattern in order to acquire a high and stable yield. For this purpose, the durum wheat variety, P1252, was selected and planted in hydroponic way. To investigate the effects of Fe deficiency, the element was eliminated from media solutions. Results showed that the lack of Fe affected superoxide dismutase (SOD), guaicol peroxidase (GPX) and catalase (CAT) activities significantly. Meanwhile, ascorbate peroxidase (APX) was the only antioxidant enzyme not shows any significant with control. The SOD/(APX + GPX + CAT) ratio as an index of assessing the balance between hydrogen peroxide (H2O2)-producing and H2O2-scavenging enzymes increased leading to the accumulation of H2O2 in cell. The elevation of SOD/APX + GPX + CAT ratio and H2O2 accumulation indicates the occurrence of oxidative stress in the leave cells in the element-deletion conditions. Other oxidative stress indices, cell death as well as malondialdehyde (MDA) did not show any significant change in the absence of Fe. The reason is assumed to be the non-occurrence of Haber-Weiss reaction in Fe absence so that hydroxyl, a very dangerous radical, is produced, leading to increased damage to cell bio-molecules and apoptosis subsequently.