Antibiosis resistance to the aphid, Sitobion avenae F. (Homoptera: Aphididae) in different winter wheat cultivars

Abstract : The nymphal survival rate; mean development time; adult fecundity (total number of progeny/female produced within the first 10 and 15 days of reproductive stage) and calculating the relevant intrinsic rate of natural population increase (rm value) was measured on five modern Iranian wheat cultivars at the tillering growth stage. The English grain aphid is regarded as one of the most important pests of small grain cereals, especially wheat varieties in many parts of the world. The pest has extended its distribution throughout the wheat fields of Iran and in particular the East Azarbaidjan province. The wheats were of Iranian origin, winter cultivars and hexaploid types, namely Alamoot, Alvand, Zarrin, Sabalan and Sardari, which are the most extensively cultivated in the province. The experiment was carried out under greenhouse conditions of 24.2±4.5°C temperature, 55.7±4.6%R.H. and 16:8(L: D) light regime. Aphids which had already been reared on the respective varieties for at least one generation were transferred to the experimental plants. The ANOVA of the data indicated that regarding duration of nymphal development time, adult fecundity and also rm values, there were significant differences (p<0.01) between the varieties. Based on this, the highest (8.70±0.47) and lowest (6.60±0.50) mean nymphal development time was calculated on Zarrin and Sardari respectively. The greatest (75.55±3.30 and 52.60±2.28) and the least (41.55±2.65 and 27.60±2.28) numbers of progeny produced per female within the first 10 and 15 days of larviposition period was observed on Alvand and Sabalan respectively. Moreover, the highest rm value (0.3340±0.0052 and 0.3304±0.0051) obtained for individuals reared on Alvand, with the lowest (0.2444±0.0089 and 0.2379±0.0093) being on Sabalan. Sabalan showed some resistance to the aphid in comparison with the other varieties at the tillering stage, while Zarrin, Sardari and Alamoot were regarded as partially resistant varieties, whilst Alvand appeared to be more susceptible one
Keyword : Antibiosis, Plant resistance, Sitobion avenae, wheat cultivars
Author(s) : , K. M. Hossein
Downloads : 1264

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