Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato Plants
A field experiment was conducted to study the intra plant distribution and temporal dispersion patterns of whitetly (Bemisia tabaci Gennadius) eggs and nymphs on tomato plants to establish a sampling method which would give accurate estimates of the population size. From the third week to the ninth...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Sultan Qaboos University
1997-01-01
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| Series: | Journal of Agricultural and Marine Sciences |
| Subjects: | |
| Online Access: | https://journals.squ.edu.om/index.php/jams/article/view/501 |
| _version_ | 1818255999926009856 |
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| author | K.M. Azam S.A. Razvi M.H. AI-Muhthuri A.A. AI-Raeesi |
| author_facet | K.M. Azam S.A. Razvi M.H. AI-Muhthuri A.A. AI-Raeesi |
| author_sort | K.M. Azam |
| collection | DOAJ |
| description | A field experiment was conducted to study the intra plant distribution and temporal dispersion patterns of whitetly (Bemisia tabaci Gennadius) eggs and nymphs on tomato plants to establish a sampling method which would give accurate estimates of the population size. From the third week to the ninth week after transplanting, terminal leaflets were collected from the outer and inner canopies of each of the upper, middle, and lower plant strata. A strong ovipositional preference was found in whitefly adults at an early crop age. A maximum of 50.6% of the eggs were deposited in the middle stratum followed by upper (36. 15%) and lower strata (13.3%). However, most of the nymphs (65.5%) were present in the lower stratum followed by middle (32.4%) and upper strata (2. l %). These findings indicated that when taking observations in egg counts the most preferred site is the upper and middle strata while for nymphal counts it is the lower and middle strata. There was a sharp decrease in egg and nymphal counts from the seventh week after transplantation which clearly indicated that, after this age , the corp is not preferred by whitefly . Egg and nymphal population of whitefly on tomato plants in the field were distributed in aggregates as evident by high variance to mean ratio. Values ranged from 2.72 to 14.36 and 4.52 to 21.82 for egg counts and nymphal population, respectively. Aggregation of whitefly eggs and nymphs in all cases might be due to the behavior of adults to congregate and to the heterogeneity of the environment . The appropriate number of leaflets required for the estimation of egg density at 10% and 20% error was found to be 149 and 37, respectively. In the case of nymphal population the numbers were 163 and 41 at 10% and 20% error, respectively. |
| first_indexed | 2024-12-12T17:20:47Z |
| format | Article |
| id | doaj.art-1cb2b05f19a94277bea4183407cc8b63 |
| institution | Directory Open Access Journal |
| issn | 2410-1060 2410-1079 |
| language | English |
| last_indexed | 2024-12-12T17:20:47Z |
| publishDate | 1997-01-01 |
| publisher | Sultan Qaboos University |
| record_format | Article |
| series | Journal of Agricultural and Marine Sciences |
| spelling | doaj.art-1cb2b05f19a94277bea4183407cc8b632022-12-22T00:17:38ZengSultan Qaboos UniversityJournal of Agricultural and Marine Sciences2410-10602410-10791997-01-0120435010.24200/jams.vol2iss0pp43-50496Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato PlantsK.M. Azam0S.A. Razvi1M.H. AI-Muhthuri2A.A. AI-Raeesi3Department of Agronomy, Horticulture, Entomology and Plant Pathology, College of Agriculture, Sultan Qaboos University, PO. Box 34, Al Khod 123, Sultanate of OmanDepartment of Agronomy, Horticulture, Entomology and Plant Pathology, College of Agriculture, Sultan Qaboos University, PO. Box 34, Al Khod 123, Sultanate of OmanDepartment of Agronomy, Horticulture, Entomology and Plant Pathology, College of Agriculture, Sultan Qaboos University, PO. Box 34, Al Khod 123, Sultanate of OmanDepartment of Agronomy, Horticulture, Entomology and Plant Pathology, College of Agriculture, Sultan Qaboos University, PO. Box 34, Al Khod 123, Sultanate of OmanA field experiment was conducted to study the intra plant distribution and temporal dispersion patterns of whitetly (Bemisia tabaci Gennadius) eggs and nymphs on tomato plants to establish a sampling method which would give accurate estimates of the population size. From the third week to the ninth week after transplanting, terminal leaflets were collected from the outer and inner canopies of each of the upper, middle, and lower plant strata. A strong ovipositional preference was found in whitefly adults at an early crop age. A maximum of 50.6% of the eggs were deposited in the middle stratum followed by upper (36. 15%) and lower strata (13.3%). However, most of the nymphs (65.5%) were present in the lower stratum followed by middle (32.4%) and upper strata (2. l %). These findings indicated that when taking observations in egg counts the most preferred site is the upper and middle strata while for nymphal counts it is the lower and middle strata. There was a sharp decrease in egg and nymphal counts from the seventh week after transplantation which clearly indicated that, after this age , the corp is not preferred by whitefly . Egg and nymphal population of whitefly on tomato plants in the field were distributed in aggregates as evident by high variance to mean ratio. Values ranged from 2.72 to 14.36 and 4.52 to 21.82 for egg counts and nymphal population, respectively. Aggregation of whitefly eggs and nymphs in all cases might be due to the behavior of adults to congregate and to the heterogeneity of the environment . The appropriate number of leaflets required for the estimation of egg density at 10% and 20% error was found to be 149 and 37, respectively. In the case of nymphal population the numbers were 163 and 41 at 10% and 20% error, respectively.https://journals.squ.edu.om/index.php/jams/article/view/501agricultural sciences |
| spellingShingle | K.M. Azam S.A. Razvi M.H. AI-Muhthuri A.A. AI-Raeesi Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato Plants Journal of Agricultural and Marine Sciences agricultural sciences |
| title | Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato Plants |
| title_full | Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato Plants |
| title_fullStr | Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato Plants |
| title_full_unstemmed | Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato Plants |
| title_short | Distribution Pattern of Sweet Potato Whitefly Bemisia tabaci (Gennadius) on Tomato Plants |
| title_sort | distribution pattern of sweet potato whitefly bemisia tabaci gennadius on tomato plants |
| topic | agricultural sciences |
| url | https://journals.squ.edu.om/index.php/jams/article/view/501 |
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