Two-spotted spider mite, Tetranychus urticae Koch, is one of the important pests of bean, which can cause severe damages on it. Silicon is one of the micronutrient elements, as its spray on the leaves can decrease the...Two-spotted spider mite, Tetranychus urticae Koch, is one of the important pests of bean, which can cause severe damages on it. Silicon is one of the micronutrient elements, as its spray on the leaves can decrease the population of the pest. In this research, the impact of four different doses of Si (0, 1, 1/5, 2 ppm) was investigated on biological and population growth parameters of T. urticae. The experiments were carried out in Petri dishes in an incubator at 25°C ± 2°C, 65% ± 5% RH and 16 L: 8 D. The duration of developmental stage was significantly affected by Si dose. The longest immature period, the shortest longevity of females and the shortest oviposition period were obtained at 2 ppm. In addition, Si dose significantly affected population growth parameters of the mite. The intrinsic rate of natural increase (rm) of the mite ranged from 0.246 to 0.215 day which lowest and the highest values were at 2 ppm and control plants, respectively. The lowest net reproductive rate (R0) and finite rate of increase (λ) of the mite and the highest value of mean generation time (T) and doubling time (DT) were estimated at 2 ppm. The results of this peruse represented that 2 ppm had better potential for decreasing the population of the two-spotted spider mite, and it can be used in the mite integrated pest management programs.展开更多
This experiment was carried out as split factorial in randomized complete blocks design with three replications in Sari, Iran during 2013 and 2014. Rice cultivars were chosen as the main factor including Tarom Mahalli...This experiment was carried out as split factorial in randomized complete blocks design with three replications in Sari, Iran during 2013 and 2014. Rice cultivars were chosen as the main factor including Tarom Mahalli and Tarom Hashemi. Nitrogen rates (34 and 69 kg N ha−1 and nitroxin) with nano-particle (nano-potassium, nano-silicon and control) selected as the subfactor. The results indicated that the amount of total tiller per hill and fertile tiller per hill for Tarom Hashemi was more than Tarom Mahalli in both years. The highest paddy yield in both years was observed for Tarom Hashemi, the main reason behind it is increasing panicle length and fertile tiller number for this cultivar. For Tarom Hashemi, the highest paddy yield (5000 kg⋅ha−1) was produced with 34 kg N ha−1 and nano potassium application. For Tarom Mahalli, the highest paddy yield 4657 kg⋅ha−1 was obtained with nitroxin and nano potassium consumption. The highest harvest index was achieved with nitroxin and nano-silicon consumption. Therefore, nano particle consumption in both cultivars resulted in improved yield.展开更多
文摘Two-spotted spider mite, Tetranychus urticae Koch, is one of the important pests of bean, which can cause severe damages on it. Silicon is one of the micronutrient elements, as its spray on the leaves can decrease the population of the pest. In this research, the impact of four different doses of Si (0, 1, 1/5, 2 ppm) was investigated on biological and population growth parameters of T. urticae. The experiments were carried out in Petri dishes in an incubator at 25°C ± 2°C, 65% ± 5% RH and 16 L: 8 D. The duration of developmental stage was significantly affected by Si dose. The longest immature period, the shortest longevity of females and the shortest oviposition period were obtained at 2 ppm. In addition, Si dose significantly affected population growth parameters of the mite. The intrinsic rate of natural increase (rm) of the mite ranged from 0.246 to 0.215 day which lowest and the highest values were at 2 ppm and control plants, respectively. The lowest net reproductive rate (R0) and finite rate of increase (λ) of the mite and the highest value of mean generation time (T) and doubling time (DT) were estimated at 2 ppm. The results of this peruse represented that 2 ppm had better potential for decreasing the population of the two-spotted spider mite, and it can be used in the mite integrated pest management programs.
文摘This experiment was carried out as split factorial in randomized complete blocks design with three replications in Sari, Iran during 2013 and 2014. Rice cultivars were chosen as the main factor including Tarom Mahalli and Tarom Hashemi. Nitrogen rates (34 and 69 kg N ha−1 and nitroxin) with nano-particle (nano-potassium, nano-silicon and control) selected as the subfactor. The results indicated that the amount of total tiller per hill and fertile tiller per hill for Tarom Hashemi was more than Tarom Mahalli in both years. The highest paddy yield in both years was observed for Tarom Hashemi, the main reason behind it is increasing panicle length and fertile tiller number for this cultivar. For Tarom Hashemi, the highest paddy yield (5000 kg⋅ha−1) was produced with 34 kg N ha−1 and nano potassium application. For Tarom Mahalli, the highest paddy yield 4657 kg⋅ha−1 was obtained with nitroxin and nano potassium consumption. The highest harvest index was achieved with nitroxin and nano-silicon consumption. Therefore, nano particle consumption in both cultivars resulted in improved yield.
