Floral Diversity and Genetic Structure of Tea Germplasm of Sri Lanka

Abstract

The role of tea germplasm in crop improvement, though well recognized, yet lacks sufficient information depriving its optimum use. About 600 accessions are conserved as tea germplasm in Sri Lanka and only 4% have been frequently utilized in breeding. Floral morphological characters are useful descriptors for preliminary characterization of genetic resources and particularly pistil traits are considered as reliable criteria in taxonomical studies of higher plants. The objectives of the present study were to conduct a comprehensive analysis on floral diversity of tea germplasm to determine the nature and extent of genetic structure of tea germplasm and to categorize accessions into major taxa. Eighty-nine accessions from the tea germplasm were characterized using 16 floral traits. Results indicated presence of considerable variation among germplasm accessions. Accessions were categorized into five different groups based on the diversity of floral traits and highly discriminating accessions were identified based on the grouping pattern. Among the traits, pistil traits were highly variable compared to other traits. Tea germplasm is predominantly represented by Cambod type accessions (68%) followed by Assam types (20%). Availability of China type accessions is low. Gaps in the germplasm collection were identified and information generated can be used for decision making in future germplasm exploration missions and breeding programme.

Single nucleotide polymorphisms facilitate distinctness‐uniformity‐stability testing of soybean cultivars for plant variety protection

“…Both applicants and PVP agencies incur significant costs in the design, planting, monitoring, and analyses of data from replicated field trials in attempts to address G×E interactions (Comstock & Moll, 1963; Camussi, Spagnoletti Zeuli, & Melchiorre, 1983; Patterson & Weatherup, 1984; Staub et al., 1996; Lombard et al., 2000; UPOV, 2002, 2019; Singh et al., 2004; Law et al., 2011; Ojo, Ajaya, & Oduwaye, 2012; Ramteke & Murlidharan, 2012; Korir et al., 2013; Kumar, 2014; Oda et al., 2015; Kumar et al., 2017; Ranatunga, Arachchi, Gunasekare, & Yakandawala, 2017; Wurtenberger, 2017; Gopal et al., 2018). For example, two cycles of field trials and data analyses are required for most species with management and data collection costs per cycle reported in the Netherlands of EUR€1855–2530 (US$2041–2783), totaling EUR€3710–5060 (US$4081–5566) per cultivar (USDA–Agricultural Marketing Service, 2016) (exchange rate 25 Oct. 2019).…”

Recent progress of intra-specific hybridization of tea (<em>Camellia sinensis,</em> (L.) O. Kuntze) in Sri Lanka

“…The tea germplasm of Sri Lanka is predominantly represented by Cambod-type accessions (68%) followed by Assam types (20%) whereas availability of China type accessions is low. Besides, recent taxonomic studies revealed that the China type accessions in the exotic germplasm will immensely be useful in future tea breeding program as parental lines (Ranatunga et al, 2017).…”