ABSTRACT.
Population growth of Rhopalosiphum padi L. (Homoptera: Aphididae) on different cereal crops

Lilian R. Descamps1*, and Carolina Sánchez Chopa12
 

The bird cherry-oat aphid Rhopalosiphum padi L. (Homoptera: Aphididae) is one of the main pests in a number of crops in the semiarid Pampas of Argentina. In the present study, the effect of different host plants, including Triticum aestivum L., ×Triticosecale Wittm., Hordeum vulgare L., Hordeum distichum L., Avena sativa L., and Secale cereale L. on biological parameters of R. padi L. was studied in the laboratory at 24 ± 1 °C, 65 ± 10% RH and a 14:10 photoperiod. Longevity, intrinsic rate of natural increase (rm), net reproductive rate (R0), mean generation time (T), doubling time (DT), and finite rate of increase (λ) of the bird cherry-oat aphid on the different cereal crops were estimated. Differences in fertility life table parameters of R. padi among host plants were analyzed using pseudo-values, which were produced by Jackknife re-sampling. Results indicated that beer barley might be the most suitable food for R. padi due to greater adult longevity (20.88 d), higher fecundity (41 nymphs female-1), higher intrinsic rate of natural increase (0.309 females female-1 d-1), lower doubling time (2.24), and lower nymphal mortality (22.2%). Therefore, it can be concluded from the present study that R. padi prefers beer barley for fast and healthy development over other cereal crops.

Keywords: Intrinsic rate, life span, bird cherry-oat aphid, winter crops.
1Universidad Nacional del Sur, Departamento de Agronomía, San Andrés s/n, Altos Palihue, 8000 Bahía Blanca, Argentina. *Corresponding author (descamps@criba.edu.ar).descamps@criba.edu.ar
2CONICET Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917 C1033AAJ,Argentina.