SUMMARY
The objective of this work was:
1. Evaluate the efficacy of acetone and petroleum ether extracts of some plants and their dusts namely:- Clove flowering buds (Syzygium aromaticum), Fruits of chinaberry (Melia azedarach), Dill seeds (Anethum graveolen), Cumin seeds (Cuminum cyminum), Datura leaves (Datura stramonium) and Lantana camara leaves (Lantana camara) against S. oryzae, R. dominica and T. castaneum
2. Investigate the repellent effect of the above mentioned plant extracts to the adults of the three insect species.
3. Investigate the contact and fumigant toxicity of Clove and dill oils against the above mentioned insects.
4. Investigate the effect of sublethal concentration of the acetone extracts of Clove flowering buds and dill seeds on certain biological aspects of T. castaneum
Tests were conducted at the stored product pests laboratory of the plant protection Department, Faculty of Agriculture Moshtohor, Benha University at 28 ±1° C and 65 ±5% RH.
The obtained results could be summarized as follows:
1. Effect of the acetone and petroleum ether extracts of various plants against the studied insects:-
1.1. Toxicity and effect of acetone extract of the various plants:
Results concerning the toxic effects of acetone extracts of the different plants on mortalities and reduction in the progeny of S. oryzae, R. dominica and T. castaneum showed the following:
S. oryzae: Adults mortality increased with increasing extract concentration and time of exposure. After 14 days from the initial treatment, mortalities were between 67.7-100, 73.3-100, 79.9-100, 65.5-98.8, 65.5-91.1 and 3.3-88.8 % at all tested concentrations of Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves acetone extract, respectively. Reduction in the progeny ranged from 82.2-100, 84.1-100, 90.8-100, 79.2-100, 61.5-86.7 and 55.9-79.2 % at various concentrations for Clove flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves acetone extract, respectively.
Results of R. dominica indicated that adults mortality was increased with rising concentration and exposure period. After 14 days following treatment, mortalities were between 73.3-100, 68.8-90, 79.9-100, 39.9-86.6, 24.4-61.1 and 28.8-75.5% at various concentrations, for Clove flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves acetone extract, respectively. Reduction in the progeny was in range from 74.0-100, 72.89-89.60, 77.83-100, 38.69-70.12, 37.46-69.95 and 28.73-66.81% at all concentrations with the extracts of Clove flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves acetone extract, respectively.
In case of T. castaneum, very low adults mortality percentages were recorded after 14 days from treatment at all concentrations of the various plant extracts. Mortalities ranged from 20-71.1, 12.2-36.6, 26.6-96.6, 20-30, 5.5-11.1 and 0-10% for Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves acetone extract, respectively. Contrarly, higher reduction in the progeny was obtained for the various plant extracts and it was between 66.3-100, 29.9-94.4, 75.8-100, 28.2-66.8, 42.5-77.5 and 1.51-15.85% for Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves acetone extract, respectively.
1.2. Toxicity and effect of petroleum ether extract of the various plants:
Results concerning the toxic effect of petroleum ether extract of various plants on mortalities and reduction in the progeny of various insect species under investigation showed that mortalities were increased with increasing concentration and time of exposure
S. oryzae: Adults mortality increased with increasing concentration and time of exposure. After 14 days from the initial treatment, mortalities were between 85.5-100, 81.1-100, 68.8-100, 74.4-100, 53.3-91.1 and 60-92.2% at all tested concentrations with Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves petroleum ether extract, respectively. Reduction in the progeny was between 84.1-100, 81.3-100, 87.7-100, 64.1-100, 34.6-76.6 and 38.40-81.40% for Clove flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves petroleum ether extract, respectively.
Results of R. dominica indicated after 14 days from initial treatment that, adults mortalities were in range from 64.4-100, 65.5-96.6, 53.3-100, 30-76.6, 23.3-75.5 and 40-78.8% at the various concentration of Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves petroleum ether extract, respectively. Reduction in the progeny was relatively higher than mortality and ranged from 79.10-100, 73.26-100, 71.95-100, 64.24-85.24, 32.53-72.08 and 79-74.04 % at various concentration of Clove flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves petroleum ether extract, respectively.
T. Castaneum: Adults mortalities recorded after 14 days from treatment were very low for the various plant extracts except of Dill seeds and ranged from 30-48.8, 25.5-32.2, 37.7-95.5, 14.4-25.5, 13.3-21.1 and 2.2-16.6 % at the various concentrations of Clove flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves petroleum ether extract, respectively. Reduction in the progeny was significantly higher than mortality and was in range from 51.64-76.20, 50.6-75.6, 53.3-99.2, 23.8-61.6, 13.6-59.9 and 5.35-37.85 % for the various plant extracts, respectively.
Data revealed also that S. oryzae adults were the most susceptible insect species followed by R. dominica and T. castaneum adults to acetone and petroleum ether extracts of the different plants under study.
Meanwhile, the obtained results indicated clearly the possibility of using the acetone / or the petroleum ether extract of clove flowering buds, Dill seeds, Cumin seeds and Fruits of chinaberry at 2% / or 1% (w/w) concentrations of grain protectants against the adults of S. oryzae, R. dominica and T. castaneum, because of their high efficiency at the above mentioned concentrations against the three insect species.
2. Effect of various plant dusts and Katel-sous dust against the tested insects:-
Results of the toxic effect of the various plant dusts at 8, 4, 2, 1 and 0.5% concentrations on mortalities and reduction in the progeny of S. oryzae, R. dominica and T. castaneum revealed the following:
S. oryzae: After 14 days from treatment, adults mortality ranged from 32.2-78.8, 21.1-56.6, 20-51.1, 30-51.1, 20-55.5, 20-53.3 and 100 % at various concentrations for Clove flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves, Lantana camara leaves and Katel-sous dusts, respectively. Reduction in the progeny was between 27.79-84.28, 25.16-65.50, 21.12-58.92, 39.27-71.42, 9.38-56.63, 24.96-64.83 and 100 % for the various plant dusts and katel-sous dust, respectively.
R. dominica: Adults mortality after 14 days from treatment was between 24.4-65.5, 20-50, 18.8-46.6, 17.7-56.6, 16.6-43.3, 15.5-45.5 and 75.5-100% for Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves, Lantana camara leaves and Katel-sous dusts, respectively. Reduction in the progeny ranged from 31.28-78.63, 34.19-65.87, 28.81-64.03, 36.93-66.40, 28.89-61.58, 37.66-65.62 and 93.34-100 % at various concentrations of the various plant dusts and Katel-sous dust, respectively.
T. castaneum: After 14 days following treatment, adults mortality ranged from 8.8-38.85, 13.3-25.5, 13.3-36.6, 8.8-23.3, 15.5-24.4, 8.8-31.1 and 21.1-86.6 % at all concentrations of Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves, Lantana camara leaves and Katel-sous dusts, respectively. Reduction in the progeny was between 30.95-60.13, 25.96-51.89, 30.19-69.62, 21.03-51.99, 28.35-49.96, 16.44-56.52 and 63.11-98.23 % for various plant dusts, respectively. At the highest tested concentration of 8 %, results indicated clearly that the reduction in the progeny was considerably greater than mortality of the various insect species with all plant dusts.
Also. S. oryzae was the most sensitive species to the various plant dusts than R. dominica and T. castaneum. The obtained results indicated clearly that the plant extracts were much more effective against various insects under study than their plant dusts.
3. Repellent effect of the acetone and petroleum ether extracts on tested insects:-
3.1. Repellency rates of acetone extracts of the various plants:
Results of the repellency rates of acetone extract of the various plants against S. oryzae, R. dominica and T. castaneum adults revealed the following.
Relatively high values of average repellency during the observation period of 14 days were recorded for S. oryzae adults with the various plant extracts. These values ranged from 34.55-57.41, 30.41-52.48, 39.18-59.62, 32.01-48.37, 43.24-64.24 and 37.57-62.17 % at all concentrations for Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves acetone extract, respectively. These values were relatively lower for T. castaneum adults and were in range from 24.40-38.35, 11.98-26.47, 22.01-32.17, 8.35-23.61, 25.65-30.10 and 17.41-25.34 % with the various plant acetone extracts, respectively.
In case of R. dominica adults repellency values were also lower and ranged from 14.24-24.55, 8.52-16.62, 12.17-22.48, 6.00-11.68, 12.81-26.94 and 5.35-19.47 % for the different plant extracts, respectively.
3.2. Repellency effect of petroleum ether extracts of the various plants:
S. oryzae adults mean repellency rate was relatively high and was from 40.10-62.56, 33.28-55.68, 41.05-56.30, 28.04-45.04, 35.18-62.80 and 31.70-57.72% at various concentrations for Clove flowering buds, Fruits of chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves petroleum ether extract, respectively.
Lower values were obtained with R. dominica adults in range from 16.92-33.91, 9.94-23.75, 15.02-29.00, 10.44-18.35, 17.72-34.22 and 18.82-29.47 % for the extracts of the different plants, respectively.
The repellency values of T. castaneum adults were also low and ranged between 20.58-33.92, 9.32-23.42, 13.75-28.04, 9.31-19.47, 22.65-33-61 and 11.85-27.24 % with petroleum ether extract of Cloves flowering buds, Fruits of Chinaberry, Dill seeds, Cumin seeds, Datura leaves and Lantana camara leaves, respectively.
4. Contact toxicity and fumigant effect of certain plant oils against the tested insects:-
4.1. Contact toxicity of essential oils on the various insects
Results concerning the toxic effects of essential oils of Clove and Dill on adults mortality of S. oryzae, R. dominica and T. castaneum showed the following:
S. oryzae adults the results showed that mortality was increased by increasing the plant oil concentration and period of exposure. After 7 days from the initial treatment, mortality was between 52.2-91.1% for Clove oil and 44.4-83.3 % for Dill essential oil.
Result of R. dominica adults indicated that mortalities were increased with rising the plant oil concentrations and time of exposure. After 7 days from the initial treatment, mortality was between 36.6-73.3% for Clove oil and 38.8-77.7 % for Dill oil.
In case of T. castaneum adults recorded mortalities after 7 days from treatment were in range from 21.1-45.5% for Clove oil and 15.5-53.3 % for Dill oil.
4.2. Fumigant toxicity of essential oils against the various insects
Results concerning the Fumigant toxicity of essential oils of Clove and Dill on adults mortality of S. oryzae, R. dominica and T. castaneum showed the following:
S. oryzae adults the results showed that mortality was increased by increasing the plant oil concentrations and period of exposure. After 7 days from the initial treatment, mortality was between 75.5-100% for Clove oil and 71.1-98.8 % for Dill oil.
Result of R. dominica adults indicated that mortalities were increased with rising the plant oil concentrations and time of exposure. After 7 days from the initial treatment, mortality was between 66.6-96.6% for Clove oil and 58.8-93.3 % for Dill essential oil.
In case of T. castaneum adults recorded mortalities after 7 days from treatment were in range from 56.6-86.6% for Clove oil and 48.8-88.8 % for Dill oil.
The results indicated also that clove and Dill oils were much more effective as fumigants than in the contact Bioassay method against S. oryzae; R. dominica and T. castaneum adults.
Meanwhile, this results showed the possibility of using these essential plant oils as grain protectants / or as Fumigants to control stored product insects.
5. Effect of sublethal concentration of Cloves flowering buds and Dill seeds acetone extracts on some biological aspects of T. castaneum
The effect of sublethal concentration (causing 50-60% adults mortality) acetone extract of clove flowering buds and Dill seeds on certain biological characteristics of Tribolium castaneum was investigated in the laboratory at 28±1°c and 65±5% RH.
Results of various treatments to T. castaneum adults could be summarized as follows:
1. Effect of Clove flowering buds acetone extract:
• Results induced significant reduction in the number of eggs laid daily per female during an observation period of two weeks compared with the control.
• Percentages of decrease in egg numbers was 59.12%.
• Significantly pre-oviposition of eggs was prolonged in comparison to control
• The mortality rate of larval instars was 38.32.
• Decrease in hatchability rate of eggs by (74.53%).
• Decrease in incubation period of eggs, duration of larvae, width of head capsule, body length and duration of pupa compared with control.
• No significant differences were observed between the treatment and control for incubation period, pupal stage and sex ratio.
2. Effect of Dill seeds acetone extracts
• Results induced significant reduction in the number of eggs laid daily per female during an observation period of two weeks compared with the control.
• Percentages of decrease in egg numbers was 50.08%.
• Decrease in hatchability rate of eggs by (82.00%).
• High mortality rate of larval instars to reach 26.41% compared with the control.
• Significantly pre-oviposition, incubation period of eggs and duration of pupa was extended in comparison to control
• Decrease in duration of larvae, width of head capsule and body length of larvae.
• No significant differences were obtained between the treatment and control for total development period of immature stages. |
