Temperature-dependent life history of Sipha maydis (Hemiptera: Aphididae) on wheat

Abstract

Sipha maydis (Passerini) is a pest of Poaceae in many cereal-growing area of the world and Iran. The effects of temperature on biology and life table were investigated at five constant temperatures (15, 20, 25, 30 and 32.5±1°C), 60±5% relative humidity (RH) and a photoperiod of 16L : 8D h. The results indicated that aphids failed to complete development at 32.5°C. Developmental time was ranged between 17.28 to 9.55 days at 15 and 30°C, respectively. The lower developmental threshold (T0) and thermal constant of S. maydis were estimated to be –5.52°C and 332.22 degree-days, respectively. The Analytis-3/Briere-1 model (as non linear model) is highly recommended for the description of temperature dependent development of S. maydis. The highest life expectancy of adults at emergence was 33.35 days at 20°C. The mean adult longevity of females and nymphipositional period were the highest at 20°C. The mean lifetime fecundity at 15, 20, 25 and 30°C were 21.24±1.97, 44.82±3.18, 22.25±2.33 and 16.39±1.15 nymphs/female, respectively. The survivorship curves of S. maydis were type I at 20 and 25°C (H 0.5). The highest and lowest values of intrinsic rate of increase (rm) were observed at 20 (0.173±0.012 females/female/day) and 15°C (0.109±0.003 females/female/ /day), respectively. The growth index (GI) at 15, 20, 25 and 30°C were 0.033, 0.069, 0.062 and 0.038, respectively. According to this research the optimum temperature for population growth of S. maydis was 20°C. Our findings provide fundamental information and when this information is used in association with other ecological data, it may be valuable in development and implementation of management programs of S. maydis.

Keywords

• cereal aphid
• development
• demographic parameters
• Iran