부산대학교 도서관

Maize (Zea mays L.), one of the three most important cereal crops worldwide, is stored in Sub-Saharan Africa to ensure the food resource availability throughout the year. However, maize stored often encounters losses in excess of 20% due to pests such as the larger grain borer, Prostephanus truncatus (Horn) (Coleoptera; Bostrichidae), a major pest of stored maize in tropical countries. This study aims to assess the maize varieties attractance and repellence for P. truncatus oviposition and to explain the role of grains morphophysical and biochemical characteristics on susceptibility. Twenty-five male/female pairs of insect were equidistantly placed in environment containing nine 30 g subsamples maize grains of the different varieties. Susceptibility parameters such as parent adults occurrence, number of emerged insects, grains damage and grains weight loss had highlighted significant differences in maize attractance and repellence to P. truncatus oviposition between maize varieties evaluated. Most attractant maize variety to P. truncatus was Synth-C, recording 6.00 ± 2.65 adults emergence per 30 g grains, with 3 times higher individuals number than that of Early-Thai followed variety. This variety (Early-Thai) recorded 2 fold or greater insects progeny than Synth-9243 and DMR-ES varieties. Inversely, most repellent varieties to P. truncatus were Across-Pool, Obatampa, SWAN, Tzee-White and Tzee-Yellow. For these maize varieties, the larger grain borer did not record emergence, and therefore the maize varieties exhibited not any attacks or losses. To assess the relationship between grains morphophysical and biochemical characteristics and varietal susceptibility, phenolics, palmitic acid, hardness, clarity, color and size of grains were evaluated according to standardized methods. Spearman binary correlations showed varietal attractance to P. truncatus oviposition was positively related to grains high palmitic acid content and large grains size. Conversely, repellent maize to P. truncatus oviposition can be described as a variety with high phenolics content and high grains clarity. [ABSTRACT FROM AUTHOR]