Bioefficacy of Tagetes minuta L. against Teranychus truncatus ehara (Prostigmata: Tetranychidae) and Aphis craccivora koch (Hemiptera: Aphididae) (Record no. 290653)
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| 000 -LEADER | |
|---|---|
| fixed length control field | 05104nam a22002057a 4500 |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 632.6 |
| Item number | ASH/BI PG |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Ashish V V |
| 245 ## - TITLE STATEMENT | |
| Title | Bioefficacy of Tagetes minuta L. against Teranychus truncatus ehara (Prostigmata: Tetranychidae) and Aphis craccivora koch (Hemiptera: Aphididae) |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) | |
| Place of publication, distribution, etc | Vellanikkara |
| Name of publisher, distributor, etc | Department of Agricultural Entomology, College of Agriculture |
| Date of publication, distribution, etc | 2023 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | xi, 66p. |
| 502 ## - DISSERTATION NOTE | |
| Dissertation note | MSc |
| 520 3# - SUMMARY, ETC. | |
| Abstract | The spider mite, Tetranychus truncatus Ehara and the black cowpea aphid, Aphis <br/>craccivora Koch are two predominant sucking pests infesting several vegetable crops <br/>in Kerala. Farmers depend heavily on chemical pesticides for the management of these <br/>pests. However, due to the adverse effects of synthetic pesticides on environment and <br/>non-target organisms, there is a growing need for environmentally benign alternatives.<br/>This has generated interest in the development of biopesticides, based on botanicals.<br/>Tagetes minuta L., commonly known as Mexican marigold or wild marigold or <br/>southern cone marigold is a plant whose pesticidal properties have been well <br/>documented.<br/> The study was carried out in the Department of Agricultural Entomology, College <br/>of Agriculture, KAU, Vellanikkara during 2020-2022. The objectives of the study were <br/>to identify the bioactive fractions of T. minuta and to evaluate the bioefficacy of the <br/>solvent fractions against T. truncatus and A. craccivora. Tagetes minuta plants <br/>cultivated in the Department of Floriculture and Landscaping, were harvested at the <br/>flowering stage followed by shade drying and grinding. The powdered botanical was <br/>extracted sequentially using hexane (non-polar), chloroform (medium polar) and water <br/>(highly polar) as solvents. The hexane, chloroform and aqueous fractions of T. minuta<br/>were evaluated for their efficacy against T. truncatus and A. craccivora in the laboratory<br/>at five different concentrations viz., 0.025, 0.05, 0.1, 0.15 and 0.2 %. <br/>The ovicidal and adulticidal effects of the solvent fractions were evaluated <br/>against T. truncatus by topical application method. Considerable ovicidal action was <br/>exhibited only by hexane fraction at higher concentrations (0.1, 0.15 and 0.2 %), with <br/>cent per cent egg mortality at 0.2 %, after 120 h of treatment. However, all the three <br/>solvent fractions caused appreciable mortality of adult mites, in a concentration <br/>dependent manner. The hexane fraction at 0.2 % and 0.15 % were significantly superior, <br/>causing 91.67 and 90.00 per cent mortality, respectively, followed by 0.2 % chloroform <br/>(66.67), 0.15 and 0.10% (56.67), and 0.2 % aqueous fraction (53.33), after 120 h of <br/>treatment. <br/> The efficacy of the solvent fractions (0.025, 0.05, 0.1, 0.15 and 0.2 %) against A.<br/>craccivora was evaluated in the laboratory on cowpea seedlings grown in paper cups.<br/>Though the highest reduction in aphid count after 120 h of treatment was recorded in<br/>hexane fraction at 0.2 % (90.00 per cent), chloroform (86.67) and aqueous fraction <br/>(85.00) also recorded reduction in aphid count on par with it, at the same concentration. <br/> Qualitative phytochemical analysis of the hexane and chloroform fractions was <br/>carried out by GC-MS/MS to identify the major bio- active constituents. The two <br/>compounds, 4-o-methylphorbol 12, 13- didecanoate and milbemycin b were found in <br/>both the fractions, while 4α-phorbol 12,13-didecanoate was found in hexane fraction <br/>only.<br/> The best concentrations of the three botanical fractions of T. minuta were tested <br/>for efficacy against T. truncatus on potted plants of amaranthus along with neem oil <br/>emulsion (2%) and horticultural mineral oil (2.5%). After 14 days of treatment, the <br/>hexane fraction recorded the highest reduction in mite population (88.78 %) followed <br/>by chloroform and aqueous fractions which were on par with each other (77.97 and <br/>76.96 %, respectively). Hexane fraction was superior to neem oil emulsion, while <br/>chloroform and aqueous fractions were found to be on par with neem oil emulsion <br/>(76.44), which is a widely recommended botanical preparation for mite pest<br/>management in different crops. <br/> The best concentrations of the three solvent fractions of T. minuta identified <br/>in the laboratory study were evaluated against A. craccivora on cowpea, in a pot culture <br/>experiment. By 10th day of treatment, the field efficacy of hexane fraction (78.95 % <br/>reduction) was comparable with that of neem oil emulsion (87.59 %), while chloroform <br/>(72.43 %) and aqueous fractions (68.20 %) were comparable with azadirachtin 1 EC <br/>(67.97 %).<br/>The results of the study indicate that Mexican marigold possess excellent <br/>acaricidal and insecticidal properties and that the plant can be explored further, for <br/>utilization in the management of spider mites as well as aphids. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Agricultural entomology |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Tagetes minuta L |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Teranychus truncatus |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Aphis craccivora |
| 700 ## - ADDED ENTRY--PERSONAL NAME | |
| Personal name | Haseena Bhaskar (Guide) |
| 856 ## - ELECTRONIC LOCATION AND ACCESS | |
| Uniform Resource Identifier | https://krishikosh.egranth.ac.in/handle/1/5810213725 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | Dewey Decimal Classification |
| Item type | Theses |
| Not for loan | Collection code | Home library | Current library | Shelving location | Date acquired | Full call number | Barcode | Date last seen | Koha item type |
|---|---|---|---|---|---|---|---|---|---|
| Not For Loan | Thesis | KAU Central Library, Thrissur | KAU Central Library, Thrissur | Theses | 27/09/2023 | 632.6 ASH/BI PG | 175845 | 27/09/2023 | Theses |