MSc

The study entitled “Morphological and biochemical characterization of brinjal
(Solanum melongena L.) genotypes” was carried out in the Department of Plant Breeding and
Genetics, College of Agriculture, Padannakkad during 2019-2021. The study was conducted
in two experiments and the objectives were to characterize the brinjal genotypes based on
morphological, biochemical and quality characters; analyze the genetic variability in collected
accessions and to identify best genotypes having high yield, superior quality as well as
resistance/ tolerance to fruit and shoot borer. The experimental material consisted of two wild
species (S. insanum and S. incanum) and twenty eight S. melongena accessions including
collections from North Kerala (Kannur-5, Kasaragod-4, Malappuram-1), accessions from
NBPGR regional station, Thrissur as well as KAU released varieties (Ponny, Haritha and
Surya).
The first experiment was laid out in a randomized block design with 30 genotypes in
three replications and observations were recorded for 12 qualitative, 18 quantitative and 8 fruit
quality and biochemical characters. The analysis of qualitative characters showed wide
variation for corolla colour and fruit characters such as curvature, shape, apex shape, pedicel
and calyx prickles, flesh density, fruiting pattern and colour. The results of analysis of variance
revealed significant differences for all the quantitative characters indicating presence of high
genetic variability. The brinjal genotypes SM-1, SM-5 and SM-11 showed superiority for
percent medium and long styled flowers (67.59%, 42.78%, 61.75%), fruit setting percentage
(63.89%, 37.59%, 55.45%), days to first harvest (61.33, 63.67, 61.67), fruit weight (111.18g,
115.28g, 106.87g) and marketable fruit yield (1874.67g, 1619.67g 1673.33g). The variance
component analysis revealed high heritability coupled with high genetic advance as per cent of
mean for all the fruit and yield characters as well as pericarp thickness, anthocyanin in fruit
peel and vitamin C indicating that most likely the heritability is due to additive effects making
selection effective based on these characters. Correlation and path analysis revealed that fruit
setting percentage, days to first harvest, fruit weight and number of fruits per plant showed
significant genotypic correlation and direct effect depicting true association of these characters
with fruit yield. Selection based on these characters will help to achieve efficient improvement
in fruit yield.
The UPGMA clustering of 30 eggplant accessions for qualitative traits revealed six
groups based on fruit curvature, corolla colour, fruit shape, fruit apex shape, fruit flesh density,
fruit colour. The genetic diversity analysis based on Mahalanobis D2
statistics for 18
quantitative characters grouped 30 accessions into thirteen clusters. The character fruit weight
contributed maximum towards diversity. The maximum intra-cluster distance was reported in
cluster V followed by cluster IV. The highest inter-cluster distance was recorded between
cluster VII and XII followed by clusters VII and VIII indicating a wide range of diversity
between these clusters providing scope for hybridization between superior genotypes of these
highly divergent clusters. The accessions SM-1, SM-2, SM-5, SM-9, SM-10 and SM-11
showed superior ranking in their respective clusters based on three yield attributes viz., fruit
weight, fruit setting percentage and marketable fruit yield identified in association and
divergence analysis.
In the second experiment brinjal accessions were screened for resistance to fruit and
shoot borer in a completely randomized design in three replications. The observations were
recorded for percentage of shoots infested and percentage of fruits infested at ten days intervals
and the accessions were grouped into six categories based on severity of damage on fruits. Wild
accessions SM-26 (S. incanum) and SM-27 (S. insanum) were found to be immune, as none of
these plants showed symptoms of infestation. SM-6 and SM-7 were rated as highly resistant
accessions. SM-1, SM-2, SM-3, SM-4, SM-5, SM-8, SM-9, SM-11, SM-14 and Haritha were
found to be moderately resistant. SM-10, SM-13, SM-20, SM-22, Ponny and Surya were
grouped as tolerant. All the remaining accessions were susceptible. Correlation studies between
fruit infestation by fruit and shoot borer with biochemical characters revealed a positive
significant correlation of fruit infestation with total sugars and protein content while a negative
correlation of fruit infestation was obtained with solasodine content as well as phenol content.
The present study resulted in identification of a fair number of high yielding resistant
lines amongst the wide collection of indigenous brinjal germplasm used. The wild relatives
from highly divergent clusters like cluster I (SM-26), cluster VIII (SM-27) and S. melongena
accessions SM-6 and SM-7 can be exploited for their shoot and fruit borer resistance.
Accessions SM-1, SM-2, SM-5, SM-9, SM-10 and SM-11 with higher nutrients (protein >1.22
g/100g and vitamin C >5.03 mg/100g), a balance of biochemical content (solasodine and
phenol) in addition to high fruit yield (~1300g to ~2100g) and comparatively lesser infestation
of fruit and shoot borer can be considered as the promising parents in future crop improvement
programs.