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bioRxiv · 10.1101/2023.07.29.551085

South Western Ghats: a niche of clove (Syzygium aromaticum (L.) Merr. & Perry) diversification

S, S. G.·P, R.
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Abstract

Survey conducted at major clove (Syzygium aromaticum (L.) Merr. & Perry) growing regions of South Western Ghats of India in the states of Kerala and Tamil Nadu identified thirty accessions with superior yield and distinct characters. Clove accessions were characterized based on twenty one qualitative and twelve quantitative traits. Variation among fifteen qualitative characters were found and the predominant traits observed were elliptical canopy shape, semi-erect branching pattern, lanceolate leaf lamina with acuminate apex, mid bud forming season, combination of 1,2,3,4,5 flower bud per cluster, medium sized bud, elliptical fruit and seed shape. Dendrogram constructed using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) method grouped thirty accessions into 5 major clusters at genetic similarity of 73%. Acc.19 was identified as a unique accession. Twelve quantitative characters were subjected to principal component analysis where three component groups were extracted, which explained 70.85 per cent of total variance. The score plot generated from the principal component loading grouped the accessions into 18 clusters. Minimal data set of four characters viz., plant height, canopy spread (EW), number of inflorescence per square meter and mature bud length was generated. Observation on the qualitative and minimum data set helps to identify the ideotypes. The geographical location was not found to influence genetic diversity. HighlightO_LIClove genotypes in South Western Ghats were surveyed and diversity identified C_LIO_LICombination of 1,2,3,4,5 flower bud per cluster was a unique character identified among cultivated clove C_LIO_LIMinimal data set of clove developed using plant height (m), canopy spread (EW), number of inflorescence per m2 and mature bud length (mm) C_LIO_LIIdeotype of clove developed C_LI

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S, S. G., P, R.. 2023-07-30. South Western Ghats: a niche of clove (Syzygium aromaticum (L.) Merr. & Perry) diversification. https://doi.org/10.1101/2023.07.29.551085

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