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This study aimed to evaluate the performance of different fungicides (chemical, botanical and bio-agent) against wheat blast under field conditions and to identify the best one for preventive spray. Among the fungicides evaluated, Nativo 75 WG (Tebuconazole 50% + Trifloxystrobin 25%), Amistar Top 325 SC (Azoxystrobin 20% + Difenoconazole 12.5%) and Cabrio Top 60 WG (Pyraclostrobin 5% + Metiram 55%) demonstrated the best results with least blast severity (4–8%) and the highest yield (78–88%). It was concluded that the mentioned fungicides can be used to control wheat head blast by spraying twice at 13–15 days interval starting with the heading stage. [ABSTRACT FROM AUTHOR]

The life table of the indigenous Neoseiulus californicus was studied at different temperatures and 65 ± 5% relative humidity under conditions of 16 h light : 8 h dark (LD 16:8). The total developmental period from egg to adult varied from 3.0 to 14.0 days at 15 to 35°C. Survival to adulthood ranges from 86.21 to 93.94%, with the highest rate at 25°C. The lower threshold temperature from egg to adult stages of females and males was 10.84 and 10.72°C, respectively, and the thermal constant was 57.14 degree-days (DD) for females and 56.18 DD for males. Total number of eggs laid by each female was the highest (70.38 eggs) at 25°C, whereas average daily fecundity was the highest (3.69 eggs/female/day) at 30°C. The net reproductive rate was the highest (48.49) at 25°C and lowest (26.18) at 30°C. Mean generation time decreased from 19.04 to 11.47 days with increasing temperature from 20 to 30°C. Both intrinsic rate of natural increase (0.284) and finite rate of increase (1.32) were maximum at 30°C. Adult longevity was the highest (42.75 days for females and 32.60 days for males) at 20°C and lowest (22.70 days for females and 15.30 days for males) at 30°C. Sex ratio was female biased and was the highest (78.08) at 25°C and lowest (70.24) at 30°C. Developmental data of five constant temperatures, temperature thresholds and thermal requirements may be used to predict the occurrence, number of generations and population dynamics of N. californicus as an important biocontrol agent of Tetranychus urticae. [ABSTRACT FROM AUTHOR]

The present study was conducted to determine the direct and residual effects of five pesticides, namely abamectin, bifenthrin, dimethoate, propargite and sulphur againstTetranychusurticaeand residual toxicity of these pesticides toNeoseiulus californicusadults. In the laboratory trials, except dimethoate, all the pesticide treatments caused 100% mortality ofT. urticaeadults within 24–48 hours. When toxicity to eggs was tested, the egg mortality for all pesticide treatments was significantly higher than the control. Except dimethoate, all the pesticides caused >90% egg mortality. In potted bean plants, all the pesticide treatments caused significant mortality ofT. urticaepopulations over control up to 21 days. The residual effects of pesticides were tested onT. urticaeandN. californicususing a leaf disc system in the laboratory. Mites were exposed to freshly sprayed leaf disc and after at 3, 7, 14 and 21. Abamectin showed higher efficacy againstT. urticaebut low toxicity againstN. californicus. Residual toxicity of pesticides toN. californicusadults varied but remained toxic toN. californicuslonger than toT. urticae. Bifenthrin had the longest residual effect on adultsN. californicus, causing mortality of 23% after 21 days; propargite and dimethoate caused <30% mortality after 14 days of exposure. [ABSTRACT FROM PUBLISHER]