Analysis of qualitative and quantitative trait variability among black pepper (Piper nigrum L.) cultivars in Malaysia

This project comprehensively documented the morphological characteristics of ten black pepper cultivars in Malaysia, focusing on diagnosing the morphological difference among the cultivars via qualitative traits. These cultivars are cv. ‘Semongok Aman’, cv. ‘Kuching’, cv. ‘Semongok Emas’, cv. ‘Semongok Perak’, cv. ‘Semongok 1’, cv. ‘Nyerigai’, cv. ‘India’, cv. ‘Lampung Daun Lebar’, cv. ‘Sarikei’, and cv. ‘Yong Petai’. The morphological characteristics had been evaluated via field-grown vine where the randomized complete block design (RCBD) was adopted and potted vine evaluation via completely randomized design (CRD). Cv. ‘Semongok 1’ showed ovate shaped leaf and anthocyanin free shoot tip; cv. ‘Semongok Aman’ had rounded shape of leaf apex and base; cv. ‘Lampung Daun Lebar’ had an oblique shape in leaf base and ‘Nyerigai’ showed erect type branching; cv. ‘Semongok Emas’ had leaf colour of Green group 137 series (RHS code) and fruit colour of Green group 141 series (RHS); cv. ‘India’ had a lanceolate shaped leaf. At the same time, this study also revealed the key differences in quantitative traits that included leaf area, length-width ratio, inflorescent length, fruit spike length, and fresh to dried berry conversion rate. The study showed that cv. ‘India’ had a low length-width ratio (Lw-1) at 1.52 and lightest seed weight at 4.07(x 10-2) g; cv. ‘Sarikei’ had the smallest leaf area (36.90 cm²), shortest inflorescence (6.06 cm), shortest fruit spike (8.07 cm), smallest fruit diameter (5.78 cm), smallest seed diameter (3.84 cm), and thinnest pericarp(1.73 cm); cv. ‘Kuching’ had the greatest number of inflorescence per branch per node (ca.58.67) and the greatest number of node/ feet of the stem (ca.4.73); cv. ‘Yong Petai’ had the longest inflorescence (12.75 cm), longest fruit spike (17.07 cm), but thinnest fruit spike (2.90 mm); and, lastly, cv. ‘Semongok Perak’ had the conversion rate (from fresh to dried black) (36.12 %) and conversion rate (from fresh to dried white) (24.21 %). The comprehensive evaluation of both qualitative and quantitative traits of all the black pepper cultivars has ensured the efficiency of cultivar identification.