ارقام گندم

Different cultivars of a host plant can have an important effect on the behavioral charectristics of natural enemies. In this ‎study, the effect of three wheat cultivars (Ehsan, Morvarid, and Tirgan) on functional responses of 4th instar larvae and adult ‎males and females of Hippodamia variegata Goeze on different‏ ‏densities (2, 4, 8, 16, 24, 32, 64, 96, 128, and 160) of 4-d-old ‎nymphs of Schizaphis graminum Rondani‏ ‏was studied. The experiments were conducted at 25±2 ˚C, 65±5% RH and 16L:8D h ‎photoperiod. The logistic regression analyses revealed that the functional responses of different growth stages of H. variegata ‎to S. graminum on differen wheat cultivars were type II. According to the results, the highest attack rate was estimated for 4th ‎instar larvae of H. variegata on Ehsan and Tirgan cultivars (0.152 and 0.154 h-1, respectively). Also, the lowest handling time ‎‎(0.127 h) was valued for 4th instar larvae on Ehsan cultivar. The predation rate of 4th instar larvae of H. variegata was also ‎highest on Ehsan cultivar. The results of this study revealed the high efficiency of 4th instar larvae of H. variegata in feeding ‎on S. graminum on Ehsan cultivar followed by Tigasn and Morvarid cultivars. Similar results were obtained for adult femles ‎and males of the predator. However, further studies are necessary to evaluate the effect of these cultivars on searching ‎bahavior and consumption rate of different stages of H. variegata on S. graminum under natural conditions. ‎

Twist disease of wheat caused by Dilophospora alopecuri is one of the diseases that is observed along with wheat seed gall nematode (Anguina tritici) in Golestan province. In order to investigate the pathogenicity of the fungus, an experiment was performed in two cases including inoculation of the fungus alone, D. alopecuri and the nematode together and nematode alone on 4 cultivars of wheat known as Ehsan, Kouhdasht, Morvarid and Line 17 under greenhouse condition. Traits such as decrease of dry weight of infected plant, decrease of plant height, number of fungus-infected plants, number of spike infected by the fungus, number of nematode-infected plants, total weight of nematode galls, number of nematode galls and average galls weight per plant were measured in different cultivars. The analysis was performed using SAS software, and the comparison of the means was achieved by the LSD test. The results of analysis of variance showed that the interaction between D. alopecuri and wheat cultivars and the effect of the fungus on the measured indices in wheat cultivars was significant. The results showed that D. alopecuri can cause disease on wheat only in the presence of A. tritici and the presence of nematode is necessary for fungal pathogenicity and its distribution in the wheat spike.

 Cereal cyst nematodes (CCNs) are acknowledged globally as a biotic constraint for wheat production, particularly under rain-fed conditions and drought stress. Among species of CCNs, Heterodear filipjevi is the dominant species in most cereal growing areas of Iran and is widespread in different regions of the country. The use of resistant wheat cultivars is considered the most effective and economical method for managing cereal cyst nematodes. The effectiveness of resistance to CCNs depends on the efficiency and durability of the sources of resistance, and on the correct identification of the nematode species and pathotype(s) present in each region. The objective of this study was to assess the reaction of common accessions of bread wheat to H. filipjevi under greenhouse conditions. The reaction of common accessions of bread wheat, including some cultivars and lines (20 accessions) to H. filipjevi was assessed according to used method for screening of wheat accessions under controlled conditions. Single wheat seeds were planted in standard small tubes. After plant emergence, tubes were inoculated with 300 freshly hatched J2 in 3 holes around the stem base. Experimental units were arranged in a randomized complete block design with 5 replicates. Plants were harvested 8 weeks after juvenile inoculation. Extracted Cysts from both root and soil counted under a stereomicroscope. The data were analyzed and the genotypes were divided into different groups based on their reactions. The results showed that Back-cross Rowshan cultivar with mean 30.2 and Silverstar cultivar with mean 6.8 had the most and the least number of cysts in soil and root of each plant, respectively. Cluster analysis divided all accessions into 4 groups. Back-cross Rowshan, Pishtaz and Pishgam cultivars were identified as highly susceptible according to higher mean of the cyst number in soil and root, in comparison to Bezostaya cultivar (Susceptible check). Mahdavi, Bam, Dena, Bahar, Sivand, Ofogh, Arg and Bezostaya cultivars were categorized as susceptible. Rowshan, Alvand, Parsi, Es-93-95 and Marvdasht accessions were grouped as moderately susceptible, and, Sirvan, M-90-9, M-90-7 and Silverstar (Moderately resistant check) accessions were identified as moderately resistant. This study revealed that Back-cross Rowshan, Pishtaz and Pishgam are highly susceptible cultivars to H. filipjevi. However, the cultivation of these wheat cultivars is common in the country. In order to impeding the damage of this nematode, it is essential to avoid cultivating these cultivars and other susceptible cultivars in infested fields to H. filipjevi.

The Mediteranean flour moth, Ephestia kuehniella Zeller (Lep.: Pyralidae) is a polyphagous pest in Iran. Effect of six wheat cultivars (Parsi, Pishtaz, Sardari, Bahar, Pishgam, Zarin) on demographic parameters of the E. kuehniella was determined at 26 ± 1 °C, 60 ± 5% RH and a photoperiod of 14:10 (L: D). The highest and lowest values of net fecundity and fertility rate were obtained on Bahar and Zarin wheat flour varieties, respectively. Also the highest and lowest values of intrinsic rate of increase obtained on Bahar (0.1076 ± 0.0018 female/female/day) and Pishtaz (0.0908 ± 0.0015 female/female/day) wheat flour varieties, respectively. The longest and shortest doubling time were observed on Pishtaz (7.58 ± 0.12) and Bahar (6.39 ± 0.10 days) cultivar, respectively. Because of the importance of population growth parameters, including intrinsic rate of increase (rm), Bahar was the most suitable host plants among the other wheat flour varieties. Determining of the suitable variety among different wheat flour would be helping us to improve natural enemy production using this pest as food on susceptible host plants.

Lesser grain borer, Rhyzopertha dominica F. is one the most important pests in Golestan province. One of the method to reduce the pest damage is using resistant cultivars. In this experiment the effect of eight cultivars and lines of wheat such as Kouhdasht, Zagros, Morvarid, Darya, Pastor, Line 17 and N-80-19, on number of live and dead adults and populatioin growth rate of lesser grain borer was studied. One hundred gram of wheat was placed in a crystal container and 10 adults were put on each container and kept under stored condition. Sampling was done every each 7 to 10 days intervals. Data were analyzied using SAS program in split-plot in time design. Analysis of variance showed that number of a live adults and population growth rate in wheat cultivars were significantly different (p

Lesser grain boror Rhizoperta dominica in widly distributed in the world wide. Its caused damage to stored product pests, specially on wheat. Damage of this pests, terminating to decrease seed weight and Viability The averege of damage and feeding rate of above pest was studied with eight lines and cultivar such as: Kouhdasht, Zagros, Morvarid, Darya, Pastor, Line 17 and N-80-19. Experiment was down as randomly complete black design with explications in laboratory canditions. A hundred grams of wheat plased in a crystal container and with 10 adult ware put on each container and them, bottle door will cover with net. seed weight, Viability Pure varietis in two stage, before pests at end to meas used expsmate. Analysis of variances has been shown all characteristics of wheat varietis todamege and feeding of Lesser grain boror wese not signiticant differences. comparison average of varieties of wheat Viability and seed weight before experimant, has not shown signiticant differences, but effect to feeding and damege of Lesser grain boror to Viability and wheat varietis has been decrease of except Morvarid variety. Morvarid variety least decrease Viability (10.34). and decrease un purity of seed (12.84) and less percantage decrease seed weight (13.07). Morvarid variety with weight of hectoliters (66.50). Darya variety with more percentage decrease weight (21.97) and more percentage decrease un purity was (21.94),but with more weight Hectoliter (67.32) after experimant and more percantage of decrease of Viability (27.33) belong to pastoor variety. These bore, feeding and damage of Lesser grain boror, these was lesse effect on Viability and physical characteristics of Morvarid seed variety and resistance (possible used that in programm of IPM) Darya varietys and Pastor was more effect feeding of pests, and it was mor on resistance variety in between other varietys has been investigcated.

Breeding and cropping cultivars with high weed competitiveness have played an important role in the nonchemical weed management. This experiment was carried out in order to study the effect of nitrogen on weed tolerance and competition indices of five wheat cultivars at the research field of agricultural faculty, University of Mohaghegh Ardabili, during 2010-2011 growing season. Experimental factors were three nitrogen rates (0, 75 and 150 kg ha-1) and five wheat cultivars (Kasgozhen, Sieson, Gaspard, Azar2 and MV 17) which grown under weedy and weed free conditions. Results showed that cultivar and nitrogen had a significant effect on stress tolerance index (TOL index). The lowest TOL was observed in MV-17 cultivar. Application of 150 kg N ha-1 increased TOL index nearly two times. Results also showed that three tolerance indices Weed interference tolerance index (WITI), mean productivity (MP) and Harmonic (HARM) had a same trend and these indices increased by increasing nitrogen rate in Kasgozhen, Sieson and Gaspard cultivars. In contrary, these indices were reduced by increasing nitrogen in MV-17 cultivar. Results showed that competitive index (CI) had a significant difference with tolerance indices. By increasing nitrogen rate CI decreased from 2.5 to. in Azar2 cultivar. Findings of this experiment indicate that weed tolerance and competitive ability of wheat cultivars are different and can be used for IWM at sustainable agriculture.

The eggs and larvae of the Mediterranean flour moth، Ephestia kuehniella (Zell.) are widely used to rear parasitoids and predators for biological control programs. In this study، nutritional responses، proteolytic and digestive amylolytic activities of the fifth instar larvae as well as some biological parameters of E. kuehniella were studied on flour of nine wheat cultivars under laboratory conditions. The longest larval period of the fifth instar was on the cultivars Back cross Roshan and Sepahan and the shortest was on cultivar Tajan. The highest daily and total fecundity was observed on N-86-7. The fifth larval instar reared on Pishtaz showed the highest efficiency of conversion of ingested food. The highest general proteolytic activity was determined on the cultivar N-86-7 and the lowest was on N-80-19. Maximum and minimum digestive amylolytic activity was determined on the cultivars Kuhdasht and Khoshki line 9، respectively. According to the results obtained، Pishtaz and N-86-7 were the most suitable cultivars for laboratory rearing of E. kuehniella as the alternative host to use in the mass production of natural enemies.

The bird cherry-oat aphid, Rhopalosiphum padi (L.), is polyphagous with a nearly worldwide distribution and known as an important pest of wheat and the main vector of barley yellow dwarf virus. In this study, the possibility of antixenosis, antibiosis and tolerance of six common wheat cultivars of Chamran, Darab 2, Shiraz, Ghods, Marvdasht and Niknezhad was investigated at 2-3 leaf growth stage in the Fars province, Iran. The experiments were conducted at 24 ± 5°C, 65 ± 5% R.H. and natural light in a greenhouse, using a randomized complete design. The analysis of variance in regard to the number of adult aphids attracted to each cultivar, was indicative of significant differences among the cultivars (P < 0.01). The highest (21 ± 0.71) and the lowest (11.6 ± 0.51) mean number of adult aphids attracted per plant was observed on Shiraz and Darab 2, respectively. The antibiosis test, based on nymphs per female was significantly different among the cultivars (P < 0.01) whose average values were 62.05, 55.84, 49.89, 47.63, 42.76 and 40.65 nymphs per female on Niknezhad, Shiraz, Ghods, Marvdash, Chamran, and Darab 2, respectively. The tolerance studies based on the damage index, showed that Chamran and Darab 2, with the lowest damage index (1.33), were the most tolerant cultivars while Shiraz and Niknezhad, with the highest damage indexes of 3.00 and 3.67 respectively, were the most susceptible cultivars. The cutivars Niknezhad and Shiraz are found to be susceptible, Ghods and Marvdasht partially resistant, and Chamran and Darab 2 resistant to the bird cherry - oat aphid.