عنوان مقاله [English]
Introduction: Bell pepper (Capsicum annuum L.) is an important plant of belong to family Solanaceae with the origin of Mexico, which is a rich source of vitamins and beneficial antioxidants to the health and the immune system. The green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) is one of the severe important pests of bell pepper in the greenhouse, which cause damage in both direct and indirect by feeding on sap and transmitting of viral diseases. The use of insecticides is the most commonly used method for controlling M. persicae, but in addition to the environmental contaminating, it increased the aphid resistance to chemical pesticides. Biological control is one of the alternative methods compatible with the crop ecosystems and is an important component in integrated pest management programs. The aphidophagous midge, Aphidoletes aphidimyza Rondani is an appropriative and important predator of various species aphids including M. persicae. Also, the quality of host plants on the first level of nutrition have important effect on the eco- physiology characteristics of the predator on the third level of nutrition. In this study, the effect of foliar application of micronutrient fertilizers of iron, zinc, copper and manganese on bell pepper was investigated on the biological and demographic parameters of A. aphidimyza fed on M. persicae in greenhouse conditions.
Materials and Methods: The experiments were done as a completely randomized design with 50 replications per treatments during 2020-2021 in the greenhouse. The foliar application of micronutrient was carried out in four-to six-leaf stages with a certain amount of each fertilizer. At the beginning of the experiment, 100 eggs were considered to investigate the study of biology and the life table parameters of A. aphidimyza reared on the M. persicae fed on in each of the experimental treatments. Then daily, these eggs on the all treatments were monitored for recording incubation duration, survival rate and larval developmental duration (50 larvae). A mixture of aphids of different stages were Placed daily on each leaves treatment to feed of A. aphidimyza. Then, the experiments and the observations continued until the emergence of adult insects. After, a pair of male and female adult insects (15 pairs per treatment) were released into each experimental container containing leaves aphid infestation. Daily, the investigate continued for recording of pre-oviposition and oviposition duration, fecundity, male and female longevity until the death of the last individual. Recording of life table parameters and data analysis was performed using the bisexual life table method in TWOSEX-MSChart software. The results were accomplished by Tukey’s post hoc Honestly Significant Difference (HSD) test for showing the mean comparisons (Mean±SE).
Results and Discussion: Based on results, the highest and lowest the intrinsic rate of increase (0.148 and 0.097 / day), the finite rate of population increase (1.160, 1.102 per day) and the net reproduction rate (15.8, and 6.42 offspring/individual) of A. aphidimyza were observed on iron and control treatments, respectively. The results show that there was a significant difference between the different treatments in terms of mean generation time (T) and the highest and the lowest T was obtained on control (19.003 day) and manganese treatment (18.096 day), respectively. Also, the foliar application of micronutrient fertilizers led to reduce the pre-adult time and increase, fecundity, oviposition period and the male and female longevity of A. aphidimyza. The results of this study show that the foliar application of plants with micronutrient fertilizers by improving the growth quality and inducing antibiotic resistance in host plants, has a positive effect on the biology and life table of A. aphidimyza.
Conclusion: The host plants, as the first level of nutrition, have important effects on the predator biology as the third level of nutrition. So, the use of micronutrients by improving the quality of host plants herbivorous insects can be affect the different aspects of the biological characteristics of the higher nutrient level in plant-herbivorous interactions.
Therefore, the foliar application of bell pepper with micronutrient fertilizers along with the use of A. aphidimyza as an appropriative biological control agent for aphids can be effective in integrated management programs of M. persicae.