Journal Article

Morphological, Phytochemical, and Genetic Variation in Hawaiian Cultivars of 'Awa (Kava, Piper methysticum, Piperaceae)

Qun Yi Zheng, Dennis J. Mc Kenna, Doug Mc Kern, Lebot, Vincent, Ed Johnston

1999

Overview

Standardized morphological descriptions, quantitative phytochemical analyses (HPLC) of major kavalactones and DNA fingerprinting (AFLP) were utilized to define the extent of variation existing between Hawaiian cultivars of Piper methysticum. For each cultivar, morphotypes and chemotypes were compared to their respective genotypes. Overall, 63 samples were analyzed for their kavalactone content and composition (44 root samples, 6 stump, 5 basal stem, 7 leaves and 1 peelings). Results obtained from different cultivars planted in an homogeneous environment (soil and climate) are quite variable for the kavalactone content of their roots. Total kavalactone content decreases when shade increases over the plants. Total kavalactone content markedly increases with fertility, irrigation and in a cultivated type of habitat. However, kavalactone content appears to be independent of the age of the plant. For all cultivars analyzed, total kavalactone content decreases from the roots to the stump; the basal stems and the leaves exhibit the lower concentration. It is also observed that there is a correlation between the total kavalactone content and the size of the roots: smaller roots tend to have a higher kavalactone content. Peelings of the bark had a higher kavalactone content than the stump and represent a very interesting by-product for the extraction industry. Chemotypes are similar in the roots and the stump, while they differ in the aerial parts where the concentrations in dihydrokavain and dihydromethysticin increase. DNA samples were extracted from fresh leaves collected on 22 accessions. Most accessions, representing all Hawaiian morphotypes were monomorphs for the 21 pairs of primers assayed. Kava in Hawai'i is a species with an extremely narrow genetic base. Morphological and phytochemical variation is obviously controlled by very few genes. Most cultivars representing different morphotypes are most likely somatic mutants from a common clonal source introduced by Polynesians during early settlements. /// Ho 'opa'a 'ia ka laulā o ka 'oko'a i waena o nā 'ano 'awa kanu (Piper methysticum) o ka Hawai'i ma nā wehewehe kino maekanu ma'amau ke kālailai heluna kemikala no nā \"kavalactone\" a me ke \"kapāla māka manumana lima\" ōewe DNA (kaila AFLKP). No kēlā me kēia 'ano 'awa ho'ohālikelike 'ia ke 'ano o ke kino, nā kemikala o Ioko a me nā ōewe. He 63 hāpana i kālailai 'ia no ka nui o nā kavalactone a me nā kemikala o loko (he 44 hāpana a'a, 6 kumu, 5 ku'ina hā, 7 lau me ka 1 ihina 'ili kumu.) I loko o ke kanu 'ia o nā 'ano 'awa 'oko'a ma loko o ke kaipuni like o ka lepo me ke ainau he 'oko'a pono nō ma nâ kavalactone o nā a'a. He emi mai ka heluna kavalactone ke pi'i ka malu o luna o nā meakanu. He pi'i na'e ka heluna kavalactone e like me ka momona o ka lepo, ka ho'okahe 'ia o ka wai, a me ka mahi 'ia o kahi kanu. Me he mea ala 'a'ohe pili o ka heluna kavalactone i ke o'o o ka meakanu. No nā 'ano 'awa a pau i kālailai 'ia, 'oi aku nā kavalactone o nā a'a ma mua o nā kumu a emi loa ma nā ku'ina hā me nā lau. 'Ike pū 'ia he pili ka heluna kavalactone i ke ana o ke a'a: 'oi aku nā kavalactione o nā a'a li'ili'i. 'O nā ihina 'ili kumu, he 'oi pū aku ka heluna kavalactone ma mua o ko ke kumu a he mea waiwai paha ia no nā pā'oihana 'awa. 'Ano like nā kemikala o nā a'a me nā kumu. 'oiai na'e he 'oko'a ko nā māhele ulu i ka lewa, kahi nona ho'i ka 'oi 'o nā k\"dihydrokavain\" me ka \"dihydromethysticin.\" 'Uī 'ia ka DNA mail loko o nā lau hou loa i 'ohi 'ia ma nā 'ako 'ana he 22. 'O ka nui o nā 'ako 'ana no loko nō ho'i o nā 'ano 1awa kanu a pau. ua like nō ka hopena i 'ike 'ia ma ke kilo 'ana i ke 'ano o nā ōewe ma nā 'oki ōwewe 'oko'a 'ana he 21 i ka DNA. He meakanu ka 'awa o ka Hawai'i i hāiki loa kona kahua ōewe. 'O ka 'oko'a o nā kino meakanu a me nā kemikala o loko he ahuwale kona pili i nā ōewe kāka'ikahi loa nō. 'O ka nui o nā 'awa kanu i 'oko'a ke kino, ua kupa huli mai nô paha mai loko mai o kekahi molekumu 'ano'ano 'ole ho'okahi i ho'opae 'ia mai e nā Polensia ma nā hō'ea mua 'ana o lākou i Hawai'i.

• Publisher: The New York Botanical Garden Press,Springer,New York Botanical Garden Press,Springer Nature B.V
• Subject: age / Agronomy. Soil science and plant productions / amplified fragment length polymorphism / Bark / Biological and medical sciences / chemical constituents of plants / Cultivars / Cultivars: description, identification, tests, catalogs / Deoxyribonucleic acid / DNA / DNA fingerprinting / Economic botany / Fertility / Fundamental and applied biological sciences. Psychology / Genetic diversity / genetic polymorphism / Genetic variation / Genetics and breeding of economic plants / genotype / Genotypes / habitats / Hawaii / Irrigation / Kava / lactones / Leaves / Liquid chromatography / Phytochemicals / Piper methysticum / Plant morphology / Plant roots / Plants / quantitative analysis / Roots / shade / soil fertility / stems / Varietal selection. Specialized plant breeding, plant breeding aims