In the academic year 2022/23, an experiment was carried out at the Laboratory of Entomology of the Chair of Phytomedicine, Agricultural Engineering, Field Crops Production, Pasture and Grassland Management (Biotechnical Faculty). We studied the suitability of common buckwheat, spelt and common millet grains as hosts of the rice weevil (Sitophilus oryzae [L.]). The effect of different temperatures (15, 20 and 25 °C) and relative humidity (55 and 75%) on rice weevils mortality was studied in the growth chamber. The experiment was carried out in two parts (50 g of grain and 100 g of grain) and in nine replicates. Initially, 30 adult rice weevils were placed in each cereal flask and then the flasks were placed in a growth chamber. Adult beetle mortality was determined on days 7, 14 and 21 after exposure. After 21 days, we removed all the live and dead beetles from all the flasks and put the grain in jars in a dark place, where they were left for two months. After two months, we have counted newly hatched adult beetles in all the jars. After processing all the data, we found that the beetle prefers higher temperatures and higher relative humidity. It was the combination of higher temperature and humidity that produced the most rice weevil offspring. Common wheat remains the best host for the pest, with the highest number of progeny found in wheat grain. The fewest newly hatched adult beetles were in millet, because of the grain being very small and the female beetles do not lay their eggs in it. Of the four plant species used in our experiment, common millet is the least suitable for rice weevil reproduction.
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