| Moringa oleifera Lam.(Moringaceae) is an important economical multi-purpose treeigenous to northwest India. Due to long history of artificial using, M. oleifera has been broadlyintroduced and cultivated all over the world. At present, the genetic background of M. oleiferais still unclear. In this study, we researched10provenances of M. oleifera. based onmorphological, cytological and molecular levels. This paper reveals the extent of geneticdiversity and the introduction route of these10provenances. The results are as follows:The analysis of morphology showed that, variations on morphology are widely existed.Width of compound leaf verifies maximum, with range from6.052to14.325cm, and a25.192%variation coefficient, followed by thousand seed weight, leaflet length, seed lengthand leaflet width; the analysis of principal component showed that, the morphologicaldifferences between provenances of M. oleifera mainly root in the leaflet area, leaflet length,petal color, leaflet shape and seed length.Analysis of cytology showed that, chromosome number of somatic cells in M. oleifera is2n=28. Chromosome is very small, about1.02-3.35μm long; the total length of chromosomesrange from46.61to53.34μm.Take advantage of SSR marker to analyze10provenances of M. oleifera, and the resultsare as follows:(1)20pairs of SSR primers revealed that five pairs of primers polymorphicpercentage (PPL) was100%in all of the provenances, three pairs of primers polymorphicpercentage is95%, two pairs of primers of polymorphic percentage is90%, efficient allelenumber (Na) is2.1500-3.0500, the average number is2.5850, the efficient number of alleles(Ne) is1.8576-2.3429, the average number is2.0779, the apparent heterozygosity (Ho) is0.4500-0.5917, the average number is0.5257, the expected heterozygosity (He) is0.4483-0.5388, the average number is0.4983, the genetic diversity of Nei (H) is0.4472-0.5271,the average number is0.4845, Shannon diversity index (I) is0.6471-0.8860, the averagenumber is0.7607, the regularindex (Fis) is0.1257-0.0270, the average number is0.0863;(2) the genetic distance of M. oleifera has an obvious positive correlationship with its geographicalposition, TW and KE have maximum genetic consistency, while TW and CU have a minimumgenetic consistency, TW and KE have a minimum genetic distance, while TW and CU have amaximum genetic distance;(3) Variations are broadly existed among provenance of M. oleifera,1.71%of them come from among groups,6.65%of them come from within groups, while91.64%of them come from individuals within provenances, genetic background is rich inindividual level.Clustering analy with UPGMA shows that10provenances can be divided into two majorgroups, provenances in the first group and provenances come from Bangalore in southern Indiaare classified as a group; provenances in the second group and provenances come from newDelhi in northern India are classified as the other group.Based on the above research results and combine them with related data, theintroduction route of M. oleifera is specified, M. oleifera originated from north India, northernIndia provenance spread down to south India, forming southern India germplasm during theprocess of cultivation by way of artificial selection. Then, towards east, northern Indiaprovenance spread to Pakokku in Myanmar; towards west, spread to Kenya in19thcentury, andthen to the USA and Cuba through Mediterranean region. For southern Indian provenance,spread east to Sagaing in Myanmar, then to Taiwan in19thcentury, and continuously to the eastto the Philippines, towards west to Kenya in the beginning of20thcentury. |
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