Genetic evaluation of cucumber (Cucumis sativus L.)

97 Pages·2016·1.25 MB·English

Genetic evaluation of cucumber (Cucumis sativus L.)
genotypes for yield and yield attributing traits

Thesis

Submitted to the

VCSG Uttarakhand University of Horticulture & Forestry
Bharsar-246123, Pauri Garhwal (Uttarakhand) India

By

Bengia Mekap

IN PARTIAL FULFILMENT OF THE REQUIREMENTS
FOR THE DEGREE OF

Master of Science
Horticulture (Vegetable Science)

June, 2016
CERTIFICATE

This is to certify that the thesis entitled “Genetic evaluation of cucumber
(Cucumis sativus L.) genotypes for yield and yield attributing traits” submitted in
partial fulfilment of the requirements for the degree of Master of Science (Horticulture)
with major in Vegetable Science of the College of Horticulture, VCSG Uttarakhand
University of Horticulture & Forestry, Bharsar, is a record of bona fide research carried out
by Miss Bengia Mekap Id. No. 14124, under my supervision and no part of the thesis has
been submitted for any other degree or diploma.
The assistance and help received during the course of this investigation have been
acknowledged.

Prof. B. P. Nautiyal
Chairman
Advisory Committee
CERTIFICATE

We, the undersigned, members of the Advisory Committee of Miss Bengia Mekap Id. No.
14124, a candidate for the degree of Master of Science (Horticulture) with major in
Vegetable Science agree that the thesis entitled “Genetic evaluation of cucumber
(Cucumis sativus L.) genotypes for yield and yield attributing traits” may be submitted
in partial fulfilment of the requirements for the degree.

Prof. B. P. Nautiyal
Chairman

Dr. Shailaja Punetha Dr. S. C. Pant Dr. Ajaya Paliwal Dr. Pankaj Bahuguna
Co-Advisor Member Member Member
ACKNOWLEDGEMENT
Prima facea, I am grateful to the God for the good health and wellbeing that were necessary to
complete this thesis.
I would like to express the deepest appreciation to my Co-Advisor Dr. Shailaja Punetha for her
valuable guidance, suggestions, constructive criticism and constant encouragement during the investigations
and preparation of the manuscript. Without her guidance and persistent help this thesis would not have been
possible.
I wish to express my sincere thanks to Chairman of my Advisory Committee, Dr. B. P. Nautiyal, for
providing me with all the necessary facilities for the research and valueable guidance in the preparation of
this manuscript.
I also want to express sincere thanks to Dr. S. C. Pant, Dr. Ajaya Paliwal and Dr. Pankaj
Bahuguna , the Members of My Advisory Committee for their valuable help during investigation and
statistical analysis of my research.
I place on record, my sincere thank you to Dr. Ghan Shyam Abrol, Dr. Vijay Kumar, Dr. Parul
Punetha and Er. Tejas Bhosle for their help in TSS analysis, disease management, encouragement and
hindi abstract preparation respectively. Mr. Reni Lal (Supervisor Vegetable field), Mr. Anil and vegetable
research farm workers for their regular supports.
I owe my sincere thanks to Dr. Sandeep Kumar Dhatwalia for his teaching and selfless moral
support during my research work and Mr. Ashok Chettri for his endless support, suggestions and valuable
guidance in the preparation of this manuscript.
I wish to extent warm thanks to all my friends especially Sonam Negi, Suyanka Rathuri, Ekta Negi
Pankaj Rana, Sunil Nagar, Chinmaya Hedge, Manoj Bundela, Nitish Arora and Rakesh Yadav, Priya
Negi, Pragya, Sarita, Rajesh, Yashwant, seniors namely Mr. Harish, Mr. Amit and Mr. Vipin, and all juniors
of vegetable department for their help in field work and also to entire batch of M.Sc. 2014-2016 for their
joyous company at different phases of this research and for keeping me mentally happy.
I also thank my loving papa (Mr. Bengia Kachung), uncle (Er. Bengia Kagung) and Mangri Adi
for their immense love, unceasing encouragement, support and attention.
I also place on record, my sense of gratitude to one and all, who directly or indirectly have lent
their hand in this venture.

Place: Bharsar
Date : Bengia Mekap
CONTENTS
Chapter Title Page No.
1-4
1 INTRODUCTION
5-21
2 REVIEW OF LITERATURE
22-34
3 MATERIAL AND METHODS
35-57
4 EXPERIMENTAL RESULTS
58-66
5 DISCUSSION
67-71
6 SUMMARY AND CONCLUSION
72-80
7 LITERATURE CITED
80-83
APPENDICES
84-85
ABSTRACT
86
VITAE
LIST OF TABLES
Table No. Title Page No.
3.1 List of cucumber genotypes used in the study 23
3.2 Allotment of treatments in the experiment field under RCBD 24
4.1 Mean performance of cucumber genotypes for vine-length, number 37
of branches and leaf area
4.2 Mean performance of cucumber genotypes for number of nodes, 39
intermodal length and days to first female flower
4.3 Mean performance of cucumber genotypes for node bearing first 40
female flower, maturity duration and harvest duration
4.4 Mean performance of cucumber genotypes for number of pickings, 42
number of marketable fruit per plant and fruit length.
4.5 Mean performance of cucumber genotypes for fruit diameter, 44
average fruit weight and pericarp thickness
4.6 Mean performance of cucumber genotypes for total soluble solids, 45
marketable yield per plant and marketable yield per plot
4.7 Mean performance of cucumber genotypes for eighteen 83
horticultural traits
4.8 Estimates of PCV,GCV, heritability, genetic advance and genetic 46
gain
4.9 Clustering pattern of nineteen genotypes of cucumber on the basis 46
of genetic divergence
4.10 Average intra and inter-cluster distance 49
4.11 Cluster means for different characters among nineteen genotypes of 49
cucumber
4.12 Phenotypic and genotypic coefficients of correlation among 51
different traits in cucumber
4.13 Estimates of direct and indirect effects of different traits on yield of 54
cucumber
LIST OF FIGURES
Figure Title Page No.
1 Graphical representation of monthly weather data pertaining to the 82
average minimum and maximum temperature, relative humidity
and rainfall during the growing season.
LIST OF PLATES
Plate Title Between
pages
1 Different operations carried out during field experiment 25-26
2 Pericarp thickness of cucumber genotypes under study 44-45
ABBREVIATIONS

% : per cent

& : and
°C : Degree centigrade
cm : centimeter
CD : Critical Difference
⁰B : degree brix
et al. : et alia (Co workers)
g : gram
i.e. : id est (that is)
kg : Kilogram
LC : Local collection
MSL : Mean Sea Level
No. : Number
SEd : Standard error of the difference
SEm : Standard error of the mean
TSS : Total Soluble Solids
viz. : videlicet (namely)
CHAPTER-1
INTRODUCTION

Cucumber (Cucumis sativus L.) with diploid chromosome (2n = 14) is one of the
most important cucurbitaceous vegetable crop grown extensively in tropical and sub-
tropical parts of the country. It belongs to the family Cucurbitaceae consisting of 118
genera and 825 species (Jeffrey, 1990). It is an annual monoecious vine with trailing or
climbing habit. It is one of the oldest cultivated vegetable crop and has been in cultivation
since 3,000 years (Wehner and Guner, 2004). China is considered as secondary center of
genetic diversification of cucumber (De Candolle, 1982) but is believed to have originated
in India (Harlan, 1975) because of the fact that Cucumis sativus var. hardwickii, progenitor
of cultivated cucumber is found in the Himalayan foot hills of India and used by native
people of Northern India as laxative (Deakin et al., 1971). From India, it spread Eastwards
to China and Westwards to Asia Minor, North Africa and Southern Europe long before
written history (Seshadri and Parthasarathy, 2002).
Cucumber is a thermophilic and frost susceptible species preferring warm weather
and bright light for its better growth and development. It grows best at a temperature range
of 18-30oC. The plants suffer from chilling injury at temperatures below 10oC (Yamaguchi,
1983). High humidity and short day length promotes female flower production (Bose and
Ghosh, 1970). However, it can be grown in both summer and rainy season in India, but it
can’t tolerate cold injury (Rastogi, 1998). In the mid and low hills of Uttarakhand, it is
grown from April-October and serves as an important off-season cash crop to the plains.
Cucumber is an important vegetable grown worldwide. In Asia, it is the fourth most
important vegetable crop after tomato, cabbage, and onion and the second most widely
cultivated cucurbit after watermelon (Tatlioglu, 1993; Wehner, 2007), while in Western
Europe, it is second only to tomato (Phu, 1997). Today cucumber is grown throughout the
world in small or large commercial farms, glasshouses and small gardens (Hossain et al.,
2010). It has tremendous economic and dietic importance. It is grown for its tender fruits,
which are consumed either raw as salad (Arunkumar et al., 2011), cooked as vegetable or
as pickling cucumber in its immature stage. It is a low energy and high water content
vegetable, and it is also a rich source of vitamin B and C, carbohydrates, calcium and
phosphorus (Yawalkar, 1985). The fruit has about 95% water content (Anonymous, 2012)
1
INTRODUCTION
which makes it diuretic, possessing a deep cooling effect. The fruits are also used as an
astringent and antipyretic. The juice is valuable medicinal food in treatment of
hyperacidity in gastric and duodenum ulcer, a good laxative for constipation (Ernestina,
2001). Seeds contain oil, which is helpful for brain development and body smoothness.
Hence, it is being used in Ayurvedic preparations (Robinson and Decker-Walter, 1999). In
addition, cucumber extract has soothing, cleansing and softening properties which are
important for the cosmetics industry and soap industries (Wang et al., 2007). Most skin
infections had been successfully treated with a cucumber extract, alpha hydroxyl acid
(Uzodike and Onuoha, 2009). Cucumber also serves as insect killer due to steroid stuffing
(Wang et al., 2007)
At present, China is the leading producer of cucumber in the world. In India, it is
grown in an area of 43.28 thousand hectares with a production of 678.15 thousand metric
tonnes (NHB, 2015).
The scope of improvement of any crop depends upon the magnitude of genetic
variability present in the available germplasm. Greater the variability in the available
germplasm, better would be the chances of selecting superior genotypes (Simmonds,
1962). India is bestowed with the wealth of cucumber germplasm, consisting both wild and
cultivated forms. Due to continuous cultivation of this cross pollinated crop, variation has
occurred for fruit and vegetative characters. Fruits vary in shape, size, colour, maturity and
taste. Before starting any breeding program, genetic variability must be available in the
parental material. Further, phenotypic variability being controlled by environmental factors
may not prove effective in crop improvement. Therefore, it is necessary to partition the
phenotypic variations into its genetic and environmental components because in the total
variability, only heritable genetic components are important. Genetic advance is also
important because it predicts the extent of advancement to next generation through
selection. While selecting for yield, one should take into account the improvement of yield
contributing traits provided that the association of such traits with yield is known.
Moreover, correlation and path coefficient analysis have been of immense help in selecting
suitable plant type. Although, correlation coefficient indicates the nature of association
among the traits, path analysis splits the correlation coefficients into measures of direct and
indirect effects. Path analysis determines the relative importance of direct and indirect
effects of fruit yield components on fruit yield (Li, 1975). Thus, it provides an
2
INTRODUCTION
understanding on direct and indirect contribution of each character towards yield.
Correlation and path analysis furnish information regarding nature and magnitude of
various association and help in measurement of direct effect of variable on other (Chandra
et al., 2010). So, in order to identify the desirable genotypes, there is an urgent need to
assess the existing variability for higher yield and quality under specific conditions (Saikia
et al., 1995).
Estimation of genetic diversity is useful tool in quantifying the degree of
divergence in a biological population at genotypic level and to assess relative contribution
of different components to total divergence both at intra and inter-cluster levels (Jatasra
and Paroda, 1978). Cluster analysis is also carried out to detect divergent parents for
hybridization programmes to identify prospective crossings and to attain meaningful
constellations of a collection of genotypes. For exploitation of heterosis, choice of suitable
parents is of utmost importance.
Cucumber, inspite of being native of Indian sub-continent and endowed with
enormous variability and genetic divergence, it remains underutilized in terms of its
economic potential and underexploited from breeding point of view i.e. very meager work
has been done to understand and improve its genetic architecture. So, there is a great need
of screening cucumber germplasm to select elite genotypes with improved quality and
higher yield for direct selection or using as a parent in hybridization programme. Many
important features of cultivated crops are not associated with discrete mendelian traits, but
are of a continuous or quantitative nature. Yielding ability is a prime example of such a
trait and is of obvious importance. Breeding for higher yields in cucumber has been one of
the important objective of many cucumber breeding programmes since 1900’s (Whitaker
and Davis 1966; Wehner et al., 1984). The final aim of cucumber breeding is improvement
of fruit yield (Wehner et al., 1989). Yield of cucumber has also been improved by breeding
for disease resistance, as well as through the use of improved cultural practices (Cargill et
al., 1975).
Though, Uttarakhand is endowed with suitable micro-climatic conditions but its
yield is quite low due to non accessibility to varieties well suited for specific production
zones. Cucumber production can be increased by bringing extra area under its cultivation
or by adopting superior varieties but it is difficult to increase the area due to the
competition with other vegetable crops. One of the possible solutions is to make cucumber
3