International Journal of Horticulture, 2016, Vol.6, No.21, 1-8
1
Research Article Open Access
Harnessing Genetic Variation Among Experimental Cashew Hybrids
Sethi K.
1
, Tripathy S.K.
2
, Lenka P.C.
1
1 Department of Fruit Science and Horticulture Technology, College of Agriculture, OUAT, Bhubaneswar, India
2 Department of Agricultural Biotechnology, College of Agriculture, OUAT, Bhubaneswar, India
Corresponding email
International Journal of Horticulture 2016, Vol.6, No.21 doi
Received: 07 Aug., 2016
Accepted: 10 Sep., 2016
Published: 10 Oct., 2016
Copyright
© 2016 Sethi et al.,
This is an open access article published under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Sethi K., Tripathy S.K., and Lenka P.C., 2016, Harnessing Genetic Variation Among Experimental Cashew Hybrids, International Journal of Horticulture,
6(21): 1-8 (doi
Abstract
A set of 71 cashew test genotypes comprising 60 experimental hybrids, eight parents (BP1, BP2, Kalyanpur bold nut,
VTH 711/4, Kankadi, M 44/3, Vittol 44/3 and BPP 30/1) and three standard checks (BH 6, BPP 8 and BH 85) was assessed for status
of genetic variation of morpho-economic traits. Number of perfect flowers revealed maximum variability (CV=50.83%) followed by
sex ratio, apple weight and nuts/panicle. BH 6 came to flower early with synchronous flowering, while F 28 and F 38 bore more than
200 perfect flowers/m
2
. B 27 and D 19 had more than 20 flowering laterals/m
2
with longer and broader panicles. All the top yielders
(D 19, H 6, B 27, A 71 and G 8) were the hybrids among which D 19 recorded highest productivity (4.34g/plant and 2.71ton/ha) with
large nut size and G 8 recorded the highest number of nuts/panicle (8.02). C30 recorded highest TSS (Brix value 17.45) with
appealing yellow apple. Few genotypes showed increased (>70 cm) trunk girth(C-41, E-3, E-16 and VTH-711/4) and compact
canopy (BH 85 and M 44/3) and more canopy spread (>5 m) in North-South direction (A 71). Above elite test genotypes with
specific morpho-economic features may be utilized as donors in future breeding programme. Besides, promising hybrids (D19, H 6
and B27) with high nut yield may be considered for large scale multiplication and follow-up commercial cultivation.
Keywords
Genetic variation; Morpho-economic traits; Cashew hybrids
Introduction
Cashew (Anacardium occidentale L.) is an evergreen tropical tree crop cultivated in an area of about 9.45 lakh ha
in India as against 3.39 mill ha in the world. India is the largest producer (7.28 lakh tonnes) of cashew over an
area of 9.82 lakh hectares with a productivity of 772 kg/ha (Saroj et al., 2014). It earns an all time record foreign
exchange ($919 million) during 2014-15 from cashew products (cashew kernel-$910 million and shell oil-$9
million) (
high/article7828878.ece).
Other major producers are Tanzania, Mozambique and Kenya. In India, Moharashtra, Andhra Pradesh, Karnataka
and Odisha are the major cashew growing states. Cashew breeding programme is constrained by need of large
experimental plots, long juvenile period, genetic vulnerability to dreadful diseases and pests due to narrow genetic
base. Cashew was introduced to the West coast of India by Portuguese less than 500 years ago (Rao et al., 1998)
and large variation in cashew genotypes exist in the coastal region of India (Rao and Swamy, 1994). It generates
random variation through open pollination and maintains high level of heterozygosity in the natural population
owing to its clonal propagation. Many workers (Cavalcanti, 2000; Singh et al., 2008; Dasmohapatra et al., 2012b;
Sethi 2015; Sethi et al., 2016) attempted to exploit such genetic variations and /or heterosis through development
of cashew hybrids for genetic improvement in cashew. However, production of cashew in India continues to be
low due to non-availability of elite clones (Ferriera-Silva et al., 2009) and suitable management practices.
Broadening the genetic base of existing germplasms by hybridization and systematic exploitation of heterosis
could pave the way for overcoming the problem of low productivity (Masawe, 1994). Therefore, an ambitious
cashew hybridization programme was taken up to develop and identify suitable heterotic hybrids with high nut
yield potential. In this pursuit, the authors report the genetic variability among hybrid clones in nut yield and
ancillary agro-economic traits as compared to their parents and standard checks.
