Comparison on the developmental duration and head capsule width of Plodia interpunctella larvae among several variety of peanuts in different oleic content.

Research on the occurrence characteristics of insect pests in different storage materials. Knowing the development characteristics of Plodia interpunctella larvae infested on several variety of peanuts in different oleic content, can provide reference on their scientific management in stored peanut. [Methods] The developmental duration, instars, and larvae head capsule width of Plodia interpunctella (Hübner) were assayed in several varieties of high oleic acid peanut kernel that included in Kainong 1715, Kainong 1760 and Kainong 301, as well as some non-high oleic acid varieties that involved in Yuhua 47, Kainong 192, Kainongbai No. 2 and Haihua No.1, at temperature of 24, 28 and 32 °C. The zero developmental temperature and effective accumulated temperature of the larvae were also calculated according to the tested temperatures and development days. [Results] There were five instars of larvae in all seven assayed varieties of peanut at three temperatures. The developmental duration of P. interpunctella larvae cultured with high oleic acid variety of Kainong 1715 was 77, 46, and 37 d, respectively. The shortest developmental duration was 53, 27, and 27 d in non-high oleic acid variety of Kainongbai No.2, at 24, 28 and 32 °C, respectively. The developmental duration of the larvae in high oleic acid variety of Kainong 1715, Kainong 1760, and Kainong 301 was significantly longer than that in others. The developmental duration from larvae to pupae was shorten with temperature increasing. The head capsule width in each larvae instar was not significantly among of peanut varieties, the time reached the same width of head capsule was different significantly. The zero developmental temperature of the larvae in high oleic acid variety of Kainong 1715, Kainong 1760, Kainong 301, and non-high oleic acid variety of Kainongbai No.2 was 16.4, 15.2, 17.3 and17.7 °C, respectively. The effective accumulated temperature in larval stage of the moth in high oleic acid variety of Kainong 1760 was highest up to 619 degree·days, and lowest (331.5 degree·days) in non-high oleic acid variety of Kainongbai No.2. [Conclusion] The development duration of the larvae in high oleic acid peanut was obviously longer than that in non-high oleic acid peanut. The head capsule width of larvae at each instar was not significantly affected by peanut in different oleic content. The developmental threshold temperature of the larvae in different peanut varieties was between 15.2 and 17.7°C. The effective accumulated temperature in larval stage in high oleic acid variety was significantly higher than that in non-high oleic acid variety. [ABSTRACT FROM AUTHOR]