جستجوی مقالات مرتبط با کلیدواژه « Rosemary essential oil » در نشریات گروه « گیاهپزشکی »

The flour beetle (Tribolium confusum du Val) is one of the most important coleopteran pests on stored products, especially cereal grains and flour. Frequent application of chemical pesticides in insect pest management has resulted in numerous side effects such as environmental contamination, threat to human health and non-target organisms, and the development of pest resistance. In the present study, the fumigant toxicity and anti-nutritional effects of rosemary essential oil on flour beetle adults were investigated. Due to the relationship between the chemical compositions of essential oils with their biological effects, the compounds of rosemary essential oil were studied by gas chromatography-mass spectrometry. Rosemary essential oil was rich in terpenic compounds, including the hydrocarbon monoterpenes (28.72%), monoterpenoids (57.03%), hydrocarbon sesquiterpenes (3.09%), and sesquiterpenoids (3.25%). The concentration of 73.5 µl/l air of essential oil caused 90.0% mortality of the pest after 24 h, which was increased to 100% by 48 h. The use of 24-h LC40 and LC50 values of essential oil, respectively equal to 26.7 and 35.5 µl/l air, reduces the nutritional indices of the pest, including consumption index, relative consumption rate, and relative growth rate after 5 and 10 days. In addition, the feeding deterrence index of the mentioned values was estimated at 40.7 and 45.9% after 5 days and 53.4 and 59.5% after 10 days, respectively. Therefore, rosemary essential oil can be introduced as one of the available and efficient agents in the management of flour beetle for further research.

The cowpea weevil beetle, Callosobruchus maculatus (Coleoptera: Chrysomelidae), is a major pest of legumes, especially cowpea , and has become a serious pest in storage crops. Therefore, controlling this insect pest using natural pesticides such as plant essential oils seems necessary. In this research, the effect of insect mating on the toxicity of rosemary essential oil against the cowpea weevil was investigated under laboratory conditions. Bioassay tests were performed in the range concentrations of 35.07 and 78.63 µl/lair for male virgin insects and 39.17 and 102.22 µl/lair for female virgin insects and there were done 55.04 to 86.49 and 62.90 to 94.36 µl/lair for one-time mated insects, respectively. Also, concentrations of 62/51 to 125.81 and 94.36 to 157.26 µl/lair were tested against multiple times mated male and female insects, respectively. Results showed that multiple mated male and female insects had the highest resistance to rosemary essential oil and the LC50 values were 90.032 µl/lair and 118.015 µl/lair for male and female insects, respectively. Virgin insects were more sensitive to rosemary essential oil and the amount of LC50 obtained was 48.173 µl/lair for male insects and 58.298 µl/lair for female insects. These results can be useful in planning pest management strategies for the cowpea weevil beetle by plant essential oils as well as the exact time of application of these compounds to achieve maximum effectiveness.