Plodia interpunctella and Oryzaephilus surinamensis are found in food storehouses including dates and palm storages. The current study aimed to determine competition and overlap potentials of the two pests of date fruits. Time series models were used to study two species populations and logistic growth model to estimate the effect of density of the species. The results revealed the environmental capacities of O. surinamensis and P. interpunctella were 433 and 1610 (maximum number per 20 g), respectively, and the population growth rates (r) were 1.2 and 1.3, respectively. Ecological balances of the two species were close to each other from the first to the third week. The population of O. surinamensis decreased in the fourth week of the competition. The highest population balance of the two species was in the 14th week. The potential of exploitable ecological niches (e_ij) and the amount of non-exploited ecological niches by any species (z_ij) for O. surinamensis was higher than for P. interpunctella from the 8th week untill the end of sampling period. The overlap of ecological niches in the two species (D) ranged from 0.94 to 1, indicating a complete overlap of temporal activity in the two populations on date palm. The current results of this study can be used by integrated pest management specialists. Information over the effects of species competition on population dynamics and their coexistence can be used to predict population status and to adopt simple pest control methods.

在食品仓库（包括枣子和棕榈贮藏室）中发现了Plodia interpunctella和Oryzaephilus surinamensis。当前的研究旨在确定两种枣果害虫的竞争和重叠潜力。时间序列模型用于研究两个物种种群，逻辑增长模型用于估计物种密度的影响。结果表明，苏里南O. surinamensis和穿刺假单胞菌的环境容量分别为433和1610（每20 g最大数量），人口增长率（r）分别为1.2和1.3。从第一周到第三周，这两个物种的生态平衡彼此接近。surinamensis的种群在比赛的第四周减少。这两个物种的最高种群平衡是在第14周。surinamensis的可利用生态位的潜力（e _ij）和任何物种未利用生态位的数量（z _ij）均比穿刺假单胞菌高。从第8周到采样期结束。这两个物种（D）中生态位的重叠范围为0.94至1，表明这两个种群在枣椰树上的时间活动完全重叠。病虫害综合治理专家可以利用这项研究的当前结果。有关物种竞争对种群动态及其共存影响的信息可用于预测种群状况并采用简单的害虫控制方法。