Effect of temperature on some biological parameters of an Iranian population of the Rose Aphid, Macrosiphum rosae (Hemiptera: Aphididae)

The rose aphid, Macrosiphum rosae, living on rose var. Black Magic, was reared in the laboratory at four constant temperatures 15, 18, 22 and 25 +/- 1 degrees C, 75 +/- 5% R.H. and 14L : 10D. Parameters investigated included developmental rate, survival, prereproductive delay and fecundity. The rate of nymphal development (0.17) was greatest at 22 degrees C. The longest developmental time (12.33 days) was recorded at 15 degrees C. The generation time was longest and shortest at 15 degrees C and 22 degrees C respectively. The lower developmental threshold was calculated to be 9.05 degrees C. Based on this, the degree-day requirement from birth to adulthood was found to be 77.5 dd. The pre-reproductive delay also decreased markedly with increase in temperature from 15 degrees C to 22 degrees C. The longest lifespan of apterous females (12.38 d) was observed at 15 degrees C, whereas the shortest (8.06 d) was at 25 degrees C. The mean adult longevity declined with increase in temperature from 15 degrees C to 25 degrees C. The fecundity of females (progeny/female) increased from 11.38 to 28.88 with increase in temperature from 15 degrees C to 22'C but then decreased to 8.38 as the temperature increased from 22'C to 25 degrees C. The largest (0.311) and smallest (0.113) r(m) occurred at 22 degrees C and 15 degrees C respectively. All of the parameters of the M rosae life cycle at the four temperatures tested were optimum at 22 degrees C. This Iranian population of M. rosae can develop at lower temperatures than an Australian Population.