Diversity analysis and reproductive biology of milk yam (Ipomoea digitata L.) (Record no. 157889)
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| 000 -LEADER | |
|---|---|
| fixed length control field | 06780nam a22001697a 4500 |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 633.8 |
| Item number | VID/DI |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Vidya K M |
| 245 ## - TITLE STATEMENT | |
| Title | Diversity analysis and reproductive biology of milk yam (Ipomoea digitata L.) |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) | |
| Place of publication, distribution, etc | Vellayani |
| Name of publisher, distributor, etc | Department of Plantation Crops and Spices, College of Agriculture |
| Date of publication, distribution, etc | 2017 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | 169 |
| 502 ## - DISSERTATION NOTE | |
| Dissertation note | PhD |
| 520 3# - SUMMARY, ETC. | |
| Abstract | The present study “Diversity analysis and reproductive biology of milk yam (Ipomoea digitata L.)” was carried out in the Department of Plantation Crops and Spices, College of Agriculture, Vellayani, during 2013-16, with the objectives of estimating the magnitude of genetic variation in morphological and biochemical traits in milk yam accessions and identifying superior accessions with high tuber yield and active ingredient content. A detailed study of reproductive biology and investigations on regional variation, influence of climatic and soil factors on phytochemical content in milk yam were also envisaged in the study. A survey was conducted in natural growing tracts of Kerala and twenty accessions of milk yam (both tubers and vines) were collected. Tubers of each accession were subjected to preliminary phytochemical screening. The accessions were raised in the field during 2015-16 for analyzing phenotypic diversity and were evaluated for yield and active ingredient content in randomized block design with three replications. Ethnobotanical information collected in the study showed that in Thiruvananthapuram District, the tuber powder along with cow milk was mainly used as galactagogue and with honey as a tonic whereas, in Kollam and other District the root powder was mainly used as galactagogue and tonic for children. Traditional medical practitioners use tubers of I. digitata for preparing galactagogues and immuno modulatory herbal medicines. Data collected on climatic soil characters of natural growing tracts of milk yam revealed that it has wide adaptability to varying climatic and soil conditions. In the initial phytochemical screening significant regional variation in phytoconstituents were noticed and accessions T20 (Udumbanchola, Idukki) along with T1 (Meppadi, Wayanad), T7, T16 and T9 (Kalliyoor, Pallichal and Punnamoodu, Thiruvananthapuram) recorded superior values for phytochemical content. High performance liquid chromatography analysis of tuber powder (T3 and T11) detected the presence of two compounds viz., Rutin and Nicotinic acid in the tuber which has not been reported so far. In the field experiment analysis of variance revealed significant variation in vine, leaf (except petiole length) and yield characters. The accessions which produced highest fresh tuber yield were T15 (870.47g), T17 (821.93g), T11 (752.3g), T12 (744.13g), T6 (698.53g) and T3 (620.27g). Among these accessions, T11 (Kumbalangy, Ernakulam District) and T3 (Panamaram, Wyanadu District) recorded superior values for phytoconstituents in both first and second year analysis. Accessions T13 and T9 (Neyyattinkara and Punnamoodu) recorded the highest values for all phytoconstituents during the second year analysis; however their tuber yield was comparatively lesser. Detailed investigations on reproductive biology of milk yam revealed that the plants exhibit moderate flowering habit and produced cymose inflorescence with bright pinkish showy flowers (5.9 x 4.2 cm) with longevity of 8-10 hrs. Pollen grains of milk yam were identified to be of monard type with pantoporate aperture morphology and spinose exine ornamentation. Shape of pollen was spherioidal with pointed spines. Diameter of pollen ranged from 63.6-102μm, spine length (8.28-11.5μm), inter spinal distance (5-6.7μm), aperture diameter (2.8-4.6μm), style length (23.5-25.8mm) and length of filament ranged from 21.2-25mm. Stigma remained receptive for eight hours from the time of anthesis. 97.81 per cent of pollens were fertile and 94.96 per cent pollens were found to be viable. 80 per cent fruit set was observed in open pollination. Five different pollinators were identified visiting the flowers for both nectar and pollens. Fruit is a capsule containing four seeds with average size of 0.7 cm x 0.8 cm. The characters, fresh and dry tuber yield per plant, number as well as girth of tubers, and protein content in the tuber showed the highest difference between PCV and GCV which indicates that the influence of environment on these characters is considerable. But lower difference between GCV and PCV for the biochemical characters viz., glycoside, alkaloids, carbohydrates, and flavonoid content in tubers and morphological characters viz., mature leaf length and breadth pointed out that the variation observed in these characters are mainly due to genetic reasons. High heritability coupled with high genetic advance was observed for morphological characters viz., plant height, internode diameter and biochemical parameters viz., carbohydrates, flavonoids and oils. This indicates additive gene action for these characters and genetic improvement can be done by selection based on phenotypic performance. Significant regional variations in phytoconstituents exist in milk yam accessions and accessions from Wyanad, Idukki and Thiruvananthapuram are rich in phytoconstituents. The phytochemical content in milk yam tubers increases with maturity and accessions with higher tuber yields need not be rich in phytoconstituents and vice versa. Two promising accession with high tuber yield and significant phytochemical content identified in the study are T3 (Panamaram) and T11 (Kumbalangy). Apart from collecting, detailed information of reproductive biology of milk yam, the study also revealed the influence of environment in yield and protein content of milk yam tubers. Glycoside, alkaloid, carbohydrates, and flavonoid content in tubers were found to be genetically controlled. An immense scope for research in I. digitata L. exists since its therapeutic and functional potential is not exploited deeply. Phytochemical profiling of the tubers is necessary to get a gross idea of the contents present in the drug which will not only help to have a chemical mapping of the drug but also will be helpful in assessing the probable mode of action of the drug. Its tuberisation morphology as well as anatomy, phytochemical characterization using sophisticated and accurate analytical tools like chromatography, spectroscopy etc. can be beneficial for authenticating the crude drug to prevent its adulteration with Vidari (Peuraria tuberosa). |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Plantation crops and spices |
| 700 ## - ADDED ENTRY--PERSONAL NAME | |
| Personal name | Jessykutty, P C (Guide) |
| 856 ## - ELECTRONIC LOCATION AND ACCESS | |
| Uniform Resource Identifier | http://krishikosh.egranth.ac.in/handle/1/5810143079 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | |
| Item type | Theses |
| Not for loan | Collection code | Permanent location | Current location | Shelving location | Date acquired | Full call number | Barcode | Date last seen | Koha item type |
|---|---|---|---|---|---|---|---|---|---|
| Not For Loan | Reference Book | KAU Central Library, Thrissur | KAU Central Library, Thrissur | Theses | 2017-12-12 | 633.8 VID/DI | 174032 | 2017-12-12 | Theses |