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Sitophilus oryzae is one of the primary pests that causes severe damage to food products. Damage of the grains cause a drastic dropping of rice quality, which significantly affected our rice industry. The amylose content and weight loss are two components that are affected due to the S. oryzae infestation. In this study, eight rice varieties namely Thai Pathumthani Fragrant White Rice 100%, Vietnam Long Grain White Rice 5%, Pakistan Basmathi Long Grain White Rice PK 385, Indian Steam Pusa 1121 Basmathi LGWR, Thai White Rice, Pakistan White Rice, Cambodian Fragrant Sen Kro Oub 5%, and Vietnamese White Fragrant Rice 2% were collected to investigate the amylose content and weight loss after six-month durations of the S. oryzae infestation. ANOVA analysis has shown a significant value, p-value=0.00, p

The saw-toothed grain beetle, Oryzaephilus surinamensis (Linnaeus) is a secondary pest of rice grains and other stored products. Lack of information on the population abundance, spatial, and temporal distribution of O. surinamensis rendered the management control strategy of this pest species less effective. The objective of this study was to investigate the abundance, spatial and temporal pattern of O. surinamensis populations from nine rice warehouses in three zones of Peninsular Malaysia (i.e., the northern, central and southern zones) for three continuous months. The results showed that the abundance of O. surinamensis populations varied significantly (p1.0 (1.212-1.579), whilst being non-significantly and randomly distributed at p>0.05 (p=0.1154-0.91032) and Ia>1.0 (0.852- 0.929). The significance of the aggregation might be due to the rapidly changing volume of the rice stock caused by the active and rapid turnover of the storage inventory. The results obtained were very valuable and informative in managing O. surinamensis infestation of stored rice by incorporating the spatial and temporal information of the pest populations in the management strategy for improving the rice and other stored products.

The sawtoothed grain beetle, Oryzaephilus surinamensis, is a secondary pest that damages rice products and other stored grains. Analysis based on the cytochrome oxidase subunit I (COI) sequences data, the number of haplotypes (Hap) (n), haplotype diversity (Hd), haplotype network, genetic distance, and phylogeny between O. surinamensis populations from four regions (small-scale), viz. the northern area (Seberang Perai), middle area (Klang), southern area (Pasir Gudang), and east coast (Kuantan) of Peninsular Malaysia, as model sampling locations, were obtained. A total of five haplotypes were detected in all the test populations, two shared (Haplotype 1 and Haplotype 3) and three unique haplotypes (Haplotype 2, Haplotype 4, and Haplotype 5) with haplotype diversity value, Hd = 0.6789 were recorded. Furthermore, the neighbour-joining (NJ), maximum parsimony (MP), and Bayesian inference (BI) trees showed a mixture of individuals from all regions in Peninsular Malaysia (Haplotype 1 to Haplotype 4), except Haplotype 5, which was grouped with foreign populations that inherited similar haplotype with those of the European samples. This study assumed a mixture of populations presumably due to human activities and related explicitly to the exportation and importation of rice products across regions. This information is vital for strategising the control management of this pest species to reduce rice storage losses.