RESEARCH ARTICLE Capsicum frutescens L. Landraces of North-East India: From Phenotypic Diversity Perspective of Unexplored Collection Sudip Kumar Dutta 1 • S. B. Singh 1 • Vanlalhmangaiha 1 • Amrita Banerjee 2 • R. S. Akoijam 1 • T. Boopathi 1 • S. Saha 1 • Somnath Roy 3 Received: 25 July 2016 / Revised: 16 January 2017 / Accepted: 8 February 2017 Ó The National Academy of Sciences, India 2017 Abstract Mizoram and Manipur are the two north-eastern states of India, where maximum diversity of Capsicum frutescens is found. Seventy two Capsicum landraces, con- sisting predominantly of C. frutescens accessions were col- lected from the major growing states of north-eastern India. Landraces were compared for 29 qualitative traits and 14 quantitative traits using multivariate methods, including clustering and principal component analysis to assess the patterns of morphological variation. Landraces collected revealed significant differences (P \ 0.0001) for all the quantitative traits. Fruit length of [ 4 cm was found in three landraces (MN-1, MN-2 and MZBEC-2), whereas smallest C. frutescens landraces (in length) were MZBEC-42 (1.15 cm), MZBEC-13 (1.17 cm) and MZBEC-55 (1.27 cm); a variation of 6.5 folds was found in fruit length. Among the 91 inter correlation coefficients studied in quantitative traits, 17 were positively significant (8 at P \ 0.01 and 9 at P \ 0.05) and three were negatively significant (2 at P \ 0.01 and 1 at P \ 0.05). Five signifi- cant principal components (PC) were identified and accounted for a cumulative variation of 69.88%. Hierarchi- cal cluster analysis grouped 72 landraces into five clusters based on the qualitative traits and into six clusters based on quantitative traits. Altogether, the present study has generated baseline information about the vast intra-specific diversity of C. frutescens landraces of North-East India. Keywords Capsicum frutescens L. Á Landraces Á Mizoram Á Phenotypic diversity Á Principal component analysis Á Clustering Introduction India is the largest producer of chillies (1.37 MT, year 2013) in the world [1]. Chillies are believed to have been introduced in India by Portuguese explorers [2] and par- ticularly in north-eastern India by Christian missionaries [3]. A wide variability in chilli fruit morphology, pun- gency, bearing habit and crop duration is found throughout India [4]. According to Pruthi [5], the genus Capsicum comprises of five main species: Capsicum annuum (comprising the NuMex, Jalapeno and Bell varieties), Capsicum fru- tescens (Tabasco variety), Capsicum chinense (Habanero and Scotch Bonnet varieties), Capsicum baccatum (Aji varieties) and Capsicum pubescens (Rocoto and Manzano varieties) having more than 200 varieties. The fruits in this genus vary widely in size, shape, flavor and sensory heat. C. frutescens L. is one of the five cultivated species in the genus Capsicum [6] and is closely related to C. chinense Jacq. [7]. The plants of C. frutescens are characterized by paired pedicels per node, perennial habit [8], waxy greenish-white corolla [9], small fruit and pedicel longer than fruit [10]. Numerous local landraces of C. frutescens are cultivated in tropical and subtropical regions of the world [11]. The north-eastern hill region (NEH), being one of the hot-spots of biodiversity in the Indian gene centre, is also & Sudip Kumar Dutta sudipiari@rediffmail.com 1 ICAR Research Complex for NEH Region, Mizoram Centre, Kolasib, Mizoram 796 081, India 2 ICAR Research Complex for NEH Region, Umiam, Meghalaya 793 103, India 3 ICAR-National Bureau of Plant Genetic Resources (NBPGR), Regional Station, Umiam, Meghalaya 793 103, India 123 Proc. Natl. Acad. Sci., India, Sect. B Biol. Sci. DOI 10.1007/s40011-017-0850-3