Correlation between the infestation level of Sitophilus zeamais Motschulsky, 1855 (Coleoptera, Curculionidae) and the quality factors of stored corn, Zea mays L. (Poaceae)

Abstract

ABSTRACT. This experiment was carried out in order to evaluate the effect of Sitophilus zeamais on physical, physiological and sanitary quality of stored corn. Samples of 500 g of the hybrid OC-705, in three replicates, were conditioned in glasses covered with a screened lid, and kept in chamber at 25±2ºC, 70±5% RH and 12 h of photophase, for 150 days. The infestation levels were 0, 5, 15 and 50 adults/replicate, for the storage periods of 30, 60, 90, 120 and 150 days. The moisture content, classification, weight loss, germination and internal infestation were evaluated monthly. Significant inverse correlations were verified between the number of insects and both the germination and the weight loss; also between the internal infestation and the germination and the standard type. The presence of S. zeamais showed a positive correlation with the weight loss, what means that the internal and external infestations contribute to the reduction of physiological and physical quality of corn seeds. The mean dry matter loss was 0,36%/day, corresponding to a consumption of 0,0001%/insect/month. As the result of those damages, the product suffered reduction of the commercial grade in 30 days, with significant loss in all quality factors.

Eucalyptus grandis and Tagetes minuta leaf powders effectively protect stored maize against Sitophilus zeamais without affecting grain organoleptic properties

“…These lead to increased respiration and consequent loss in quality of the grain (Tefera et al, 2011;Caneppele et al, 2003). This also pre-disposes the grain to secondary attack by disease causing pathogens such as Aspergillus flavus Link leading to production of mycotoxins (Beti et al, 1995;Freer et al, 1990).…”

Efficiency of using insecticide plants on control of maize weevil, Sitophilus zeamais Motschulsky, (Coleoptera: Curculionidae)

“…La producción de estos desechos se debe a que una vez que las hembras ovipositan en perforaciones dentro del grano cubren sus huevos con un mucílago transparente y las larvas se alimentan del endospermo del grano hasta la formación de la pupa (García-Lara et al 2007). Durante el crecimiento, estas larvas consumen una cantidad de alimento mayor que su peso, produciendo un daño directo al alimentarse del embrión o endospermo, causando pérdida de peso, reducción de la germinación y menor cantidad de nutrientes, por consiguiente, disminuye la calidad de las mismas que tiene como resultado final un precio reducido en el mercado (Caneppele et al 2003). …”

Spinetoram’ın fasulye üzerinde fasulye tohum böceği, Acanthocelides obtectus Say. (Coleoptera: Bruchidae)’a karşı rezidüel toksisitesi

“…Larvae developing within the grain cause the largest damage (Swella & Mushobozy, 2007), causing a reduction of dry matter and, hence, grain mass (Padin et al, 2002). Thus, besides the reduction in grain weight, the insects destroy the embryo while feeding, reducing the germination ability of the beans (Padin et al, 2002;Caneppele et al, 2003). Given the destructive power of bruchids, many farmers sell their entire crop of beans immediately after harvest when the prices in the market are still low, and they do not store seeds for the next sowing season or for their own consumption (Schmale et al, 2006;Lopes et al, 2015).…”