ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Susceptibility of three physical forms of three oilseeds to Oryzaephilus mercator and the effects of infestation on seed quality

Martins R., Fortunato E., Dudu P., Lale N.E.S. and Okiwelu S.N.

Postharvest Biology and Technology, Volume 7, Number 3, February 1996 , pp. 277-283.

1996

บทคัดย่อ

Three physical forms (whole, broken and milled) of three oilseeds, Irvingia gabonensis (mango), Citrullus lanatus (melon) and Arachis hypogaea (groundnut) were assessed for their relative susceptibility to infestation by the merchant beetle (Oryzaephilus mercator) under laboratory conditions [25-30°C and 77-90% relative humidity (RH)]. In addition, whole seeds of each commodity were also infested with adult merchant beetle and stored for three, six and nine months under identical conditions. Higher numbers of eggs were laid on mango seeds and on the broken and milled seeds in comparison with melon and groundnut seeds and the whole seeds, respectively. Development was, however, longer in mango seeds than in melon and groundnut seeds. There were no significant differences in developmental periods of the merchant beetle between the physical forms of the oilseeds. Higher numbers of adults relative to the numbers of eggs laid emerged from groundnut seeds and generally from broken and milled forms of each oilseed. Moisture content increased in oilseeds stored for nine months, whereas protein content of the seeds decreased during the same period. With only occasional exceptions, the oil contents of mango and melon decreased with increasing storage time and infestation. In contrast, the oil content of groundnut generally increased with increasing storage time. The number of adult merchant beetle was usually significantly higher on the commodities as storage time increased. Availability of oil to the immature stages and perhaps seed hardness were suggested as possible factors which influenced the rate of development of this beetle.