Some biological aspects and life table of the oat bird-cherry aphid, rhopalosiphum padi l. (homoptera : aphididae) as function of temperature

Some biological aspects and life table of the oat bird-cherry aphid, Rhopalosiphum padi L. feed on wheat (Sids 1) were studied at constant temperatures of 18º ± 2, 22º ± 2 and 26 ± 2ºC. At a given temperatures, the time needed for the development of nymphal instars decreased significantly with the increase in temperatures. The longest period was recorded at 18 ± 2ºC while the shortest one was found at 26 ± 2ºC. The calculated developmental threshold (t0) of the whole nymphal stage was estimated as 12.66ºC. The thermal units needed for the development of the whole nymphal stage of the oat aphid were 67.95 day-degrees. Generation time (GT), reproductive potential (R0), population-doubling time (DT), intrinsic (rm) and finite rate (λ) of increase of the pest were also computed and discussed. Based on the obtained data, temperatures of 22° ± 2 and 26 ± 2°C were the most suitable temperatures for the development and multiplication of the oat aphid.