Effect of Temperature and Humidity on the Development, Longevity and Predatory Potential of Pharoscymnus flexibilis Muls. on San Jose Scale

The influence of temperature (22, 24, 28, 32 and 37 °C) and relative humidity (45, 65, 85 %) on the development, survival, fecundity and predatory potential of Pharoscymnus flexibilis Muls. was observed. The optimum temperature and humidity for the development of different stages of P. flexibilis and predatory potential were observed to be 28°C and 65% relative humidity respectively. The beetles hibernate at 22°C and could survive for more than 175 days, while at 37°C, they died within 5-10 days. P. flexibilis was observed to consume on an average 1362, 2537 and 2110 San Jose Scale crawlers at 24, 28 and 32 °C, respectively throughout its larval and adult life span.