Comparative Studies on Development and Reproduction of Four Cereal Aphid Species Reared on Sorghum or Barley to Evaluate as Alternative Prey for Banker Plant System

Abstract

Intrinsic rates of the natural increase of four cereal aphid species, Melanaphis sacchari (Zehntner), Rhopalosiphum maidis (Fitch), Rhopalosiphum padi (L.), and Schizaphis graminum (Rondani) reared on sorghum or barley were compared in order to evaluate their usefulness as alternative hosts for a banker plant system using predators such as an aphidophagous gall midge, Aphidoletes aphidimyza (Rondani), especially for the use in the hot season. Survivorship curves, total survival period, and fecundity of each aphid species on the leaf fragments of the two host plants were examined at four constant temperatures. Based on these data, intrinsic rates of the natural increase of all aphid species were calculated. On the leaf fragments of sorghum, M. sacchari had the highest intrinsic rate of a natural increase among four aphid species at all temperatures. On leaf fragments of barley at 20°C, 25°C and 30°C, S. graminum showed the highest intrinsic rates. These results suggest that the combination of sorghum as banker plants, and M. sacchari as alternative hosts, could be suitable for use in the hot season. Based on the results, the usefulness of these banker plants and alternative hosts in commercial greenhouses was discussed.

Potential Population Growth of Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae) under Six Constant Temperatures on Grain Sorghum (Sorghum bicolor L.)

“…Lopes-da-Silva et al 2014found an intrinsic rate of increase of M. sacchari on sorghum at 24 °C of 0.30, a much smaller value than the present study found at 25 °C (0.405). We found that r m doubled when the temperature increased from 15 to 25 °C, and the same rate was observed for M. sacchari on sorghum by Abe et al (2011). However, Abe et al (2011) observed that the r m increased from 0.390 at 25 °C to 0.450 under 30 °C, whereas in the present study the r m decreased from 0.405 to 0.124 when the temperature increased from 25 to 30 °C.…”

“…We found that r m doubled when the temperature increased from 15 to 25 °C, and the same rate was observed for M. sacchari on sorghum by Abe et al (2011). However, Abe et al (2011) observed that the r m increased from 0.390 at 25 °C to 0.450 under 30 °C, whereas in the present study the r m decreased from 0.405 to 0.124 when the temperature increased from 25 to 30 °C. At 24 °C, M. sacchari R 0 was 27.70 (Lopesda-Silva et al 2014), while in the present study, M. sacchari population growth from 1 generation to the next was nearly 6 times higher at 25 °C.…”

“…Previous work in Asia with M. sacchari indicated that temperatures over 20 °C decreased longevity and fecundity while increasing mortality (van Rensburg 1973a;Chang et al 1982;Kawada 1995;Abe et al 2011). However, the M. sacchari intrinsic rate of increase (r m ) is known to increase with rising temperatures (Abe et al 2011), and M. sacchari populations build up faster in summer than in winter, when an individual female can produce up to 96 nymphs (Chang et al 1982), resulting in infestations of up to 30,000 aphids per plant (van Rensburg 1973b). In a study after the sorghum outbreaks in the USA, Michaud et al (2017) observed that M. sacchari on sorghum plants took 5 to 6 d to develop at 23 °C.…”

Functions of banker plants for biological control of arthropod pests in protected culture.

“…Development and reproduction of four cereal aphid species on sorghum and barley allowed for evaluating alternative prey for banker plant systems using the aphid predator aphidophagous gall midge Aphidoletes aphidimyza (Rondani). The results suggested that the combination of sorghum as banker plants and the sugarcane aphid Melanaphis sacchari (Zehntner) as alternative hosts could be suitable for use in hot seasons [17]. Bottom-up effects were evaluated using four cereal plant species with three levels of reproductive performance of R. padi and A. colemani, the most common banker plant system used worldwide.…”

Host species-dependent and size-dependent ecological characteristics of Ephedrus nacheri (Hymenoptera: Braconidae)

“…Thus, the bootstrap method was used to estimate r (Efton 1982). Random sampling and calculation of r were repeated 1000 times by use of Mathematica 5.1 (Wolfram Research 2004, Abe et al 2011. To compare r-values, a Kruskal-Wallis test and a Bonferroni-weighted U-test were conducted, because the distribution calculated by use of the re-sampling method was not guaranteed to produce a normal distribution (Efton 1982).…”