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 <0.05 for the relationship between amylose content and rice varieties, whereas the weight loss in the eight rice varieties also showed a significant value, p-value= 0.00, p< 0.05. The Pakistan White Rice has recorded the highest percentage of weight loss (55.8%), while Cambodian Fragrant Sen Kro Oub 5% showed the lowest percentage of weight loss (23%). Despite the significant weight loss, the amylose content in each rice variety has showed a low rate, 2-9%. Results obtained from this study are considered as a fundamental data to strategize the S. oryzae pest management to make sure the continuity of rice supply for Malaysia

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 (p<0.05, p= 0.00) between zones, with the highest abundance for this species (69%) recorded from the Klang District, in the central zone, followed by Pasir Gudang (27%) in the southern zone, and Seberang Prai (4%) in the northern zone. The patterns of population abundance also showed significant differences between months, p<0.05 (p-value= 0.00-0.011) between all the warehouses. The factors that could be associated with the highest abundance of the pest were attributed to poor sanitation at the warehouses and inconsistency in the fumigation regime. For the spatial distribution analysis, SADIEShell_122 and Surfer8 software were applied. The distribution patterns of O. surinamensis populations varied significantly in all the warehouses, being significantly aggregated at p<0.05 (p=0.0385-0.0513) and Ia>1.0 (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.