GENETIC VARIABILITY AND HERITABILITY IN SNAKE CUCUMBER

GENETIC VARIABILITY AND HERITABILITY IN
SNAKE CUCUMBER
Abd Rabou, A. M.1; M.M. Ramadan2 and M. Abdel-Fatah 3
1- Vegetables, Medicinal and Aromatic Plant Breeding Department, Hort. Res. Inst,
Agricultural Research Center (ARC), Giza, Egypt.
2- Pests and Plant Protection Department, National Research Center(NRC) Giza,
Egypt..
3- Vegetables Department, Agricultural Fac., Cairo Unv., Giza, Egypt.
Corresponding author: aymanabdrabou40@gmail.com
Key Words: Genetic Variability, Heritability, Snake cucumber.
ABSTRACT
This study was conducted at Kaha Vegetable Research Farm
(K.V.R.F), Qalubia governorate during the period from 2015 to 2017 to
determine the genetic variability, and heritability among some snake
cucumber inbred lines. The treatments consist of fifteen snake cucumber
inbred lines, laid out in randomized complete block design (RCBD) and
replicated three times. Inbred lines were evaluated for nine characters to
determine variability and estimate heritability. Analysis of variance revealed
highly significant (P<0.05) for all studied characters. L17, L12, L19, L20,
L23, L24 and L27 were high resistant and resistant for powdery mildew.
The results indicated the presence of substantial variability among the inbred
lines. Genotypic coefficient of variation (GCV), phenotypic coefficient of
variation (PCV) and broad Sense heritability (h2) estimates ranges from to
8.65% - 74.24%, 9.03% - 76.84% and 84.33 to 98.96% respectively. The
high estimates of GCV and PCV in number of fruit plant (64.62 and 68.16
% respectively), sex ratio (74.24 and 76.84% respectively), and total yield
plant (64.00 and 69.69% respectively) indicated the existence of variability
and selection can be done. Whereas high estimate of h2 for all the tested
traits indicated that these characters were highly heritable and selection can
be imposed. L19 and L24 were resistance for powdery mildew and had best
marketable yield and fruit quality. Therefore, it is recommended for an
effective selection of those characters which could be adopted for cultivar
improvement program and more research is needed to validate the findings.
INTRODUCTION
Snake cucumber (Cucumis melo L. var. flexuosus) belongs to the
family Cucurbitaceae. It is a type of long, slender fruit which tastes like a
cucumber and looks somewhat like a cucumber inside and used when
immature as an alternative to cucumber (Nuñez et al. 2008). It is an
important crop, especially in the Middle East and North Africa. It is also
known as Chinese, Oriental, Armenian, serpent cucumber (Splittstoesser
1990) or snake melon. It is actually a variety of muskmelon (C. melo), a
species closely related to the cucumber (C. sativus). The skin is very thin
Egypt. J. of Appl. Sci., 36 (3) 2021 59-72
and bumpless. It has no bitterness and the fruit is almost always used
without peeling (Abdel-Ghani and Mahadeen 2014).
Powdery mildew is a Very dangerous disease which reduces the
yields of melon and other cucurbits, worldwide. Infection by powdery
mildew is greatly influenced by the plant stage, humidity of air and
temperature (Floris and Alvarez 1991). Singh (1987) reported that the
fungi can sporulate and cause infection in very dry as well as wet
atmosphere. Inbred lines with useful genes and quantitative resistance to
powdery mildew, independent of environment are of prime importance.
Genetic control of resistance/tolerance to powdery mildew has been
investigated using progeny resulting from crosses between susceptible and
resistant/tolerant genotypes (Kenigsbuch and Cohen1989). There is a high
variability among snake cucumber landraces for morphological characters,
yield and fruit attributes (Abd El-Salam et al. 2010 and Mohamed et al.
2015). Snake cucumber plants have an outcrossing habit, so in this case
landraces and local cultivars are populations of random mating individuals
(Youssef 2018). Genetic variability studies provide the essential information
about the genetic components of the population. The progress in snake
cucumber breeding depends mainly on the magnitude of genetic variability
present in the population and it is necessary to evaluate the genetic
parameters such as genetic coefficient of variation, heritability and genetic
advance (Abd El-Salam et al. 2010) Selection is the most efficient method
for traits with high heritability. The information on heritability in
conjunction with genetic advance are reliable estimations to identify
characters for enforcing selection (Johnson et al. 1955). Heritability
provides information on the magnitude of the inheritance of characters from
parent to offspring, while genetic advance shows the degree of gain obtained
in a character under a particular selection pressure (Nwangburuka et al,
2012 and Ogunniyan et al. 2015)
The high heritability associated with high genetic advance for
quantitative traits offer a better scope of selection of genotypes in early
segregating generations. Broad sense heritability magnitudes in snake
cucumber were high for number of fruits plant-1, yield plant-1, fruit length
and fruit shape index (Abd El-Salam et al. 2010), so phenotypic selection
for these traits would be reasonably effective. Moreover, it has been reported
the association of number primary branches with stem length; fruit length
with stem length; stem pubescence with both groove width and number of
female to male flowers ratio; and fruit thickness with fruit length and fruit
color with stem pubescence; that can be used in selection (Mohamed et al.
2010).
Estimates of phenotypic variance (ϭ2ph) were larger than the
corresponding genotypic variance (ϭ2g) for all examined traits. Moreover,
close estimates of phenotypic coefficient of variation (PCV) and genotypic
60 Egypt. J. of Appl. Sci., 36 (3) 2021
coefficient of variation (GCV) were noted in all characters, which imply the
contribution to phenotypic expression of these characters are mostly due to
genetic factors, while the environmental ones were not great importance
(Youssef 2018). Although genotypic coefficient of variation revealed the
extent of genetic variability present in the genotypes for various traits, it
does not provide full scope to assess the heritable variation. Burton (1952)
suggested that GCV together with heritability estimates would give the best
insight into the extent of the advance to be expected by selection.
Heritability help in determining the influence of environment in
expression of the characters and the extent to which improvement is possible
after selection (Yadav et al. 2012). Abd El-Salam et al. (2009) indicated
that broad sense heritability in snake cucumber was high for number of
fruits/plant, yield/plant, and fruit length, but it was moderate for fruit
diameter.
Despite the large variation that has been observed among snake
cucumber cultivars, the efforts for development of new and superior
varieties are still limited. Substantial effort has to be directed towards
genetic breeding of existing cultivars (Youssef 2018). Hence, the objectives
of this study are the genetic improvement of some snake cucumber inbred
lines and study the genetic behavior of some economic traits.
MATERIALS AND METHODS
This study was conducted in Kaha Vegetable Research Farm
(K.V.R.F), Qalubia governorate, Egypt during the period from 2016 to
2017. Fifteen inbred lines of snake cucumber (Cucumis melo L., var.
flexuosus) were collected from Veget. Breed. Dep. of Hort. Res. Inst.,
gene bank of Sweden, gene bank of Netherland and open pollinate
varieties from Pakistan (Table 1). All inbred lines were selfed for five
generations to ensure homozygosity.
Table 1. Sources and performance of snake cucumber accessions
used in the current study.
No. Inbred lines Bitterness Color Region
1 L4 -------- Dark green Veget. Bred. Dep.
2 L12 -------- White Pakistan
3 L14 **** White Pakistan
4 L16 -------- Dark green Veget. Bred. Dep.
5 L17 *** Dark green Gene bank of Sweden
6 L18 *** Light green Gene bank of Sweden
7 L19 -------- Green Gene bank of Sweden
8 L20 -------- White Pakistan
9 L21 -------- Light green Veget. Bred. Dep.
10 L22 -------- White Pakistan
11 L23 -------- Dark green Gene bank of Netherland
12 L24 -------- Dark green Gene bank of Sweden
13 L25 -------- White Pakistan
14 L26 *** Dark green Gene bank of Netherland
15 L27 *** Dark green Gene bank of Netherland
Egypt. J. of Appl. Sci., 36 (3) 2021 61
The evaluation of resistance for the inbred lines to powdery mildew
was carried in (K.V.R.F) during March 2015.
Inoculation with pathogen:
Plants of three leaves stage were inoculated with powdery mildew
spores using the spray inoculation method in March 2015 The infected
leaves as spores source were collected from infected melon plants, and
spores were used to make a suspension solution with density of 20
spore/sight (10×10 fold) as described by Tang et al (2003). Data were
recorded after 6 weeks of inoculation with spore suspension of E.
cichoracearum.
Disease assessment:
Infection on plants was measured 30 days after inoculation in the
greenhouse. A linear 0–4 scale (Table 2) indicating average rating of all
the leaves was used to assess the disease in experiment. On the basis of
scoring of 3 individual leaves per plant and 10 plants in each inbred line,
Percent Disease Index (PDI) was calculated for each inbred line using the
formula proposed by Wheeler (1969):
Seeds of 15 inbred lines were directly planted for horticultural
evaluation in (K.V.R.F) on open field at 16th March, 2016 and 21th
March 2017 In each trial a randomized complete block design (RCBD)
was established for 15 treatments with 3 replicates, each replicate
consisted of 15 plots each plot contained 10 plants represent the inbred
lines. Plants were grown on ridges with dimensions of 40 m long and 1 m
wide. The area of each plot was 2.5 m2; plants were grown at a distance
of 50 cm apart on both sides of the ridge. All the agriculture practices
were carried out according to the recommendation of Ministry of
Agriculture, Egypt.
Table 2. Powdery mildew disease severity estimating into 5
categories according to James (1971).
Scale Mildew covering of leaf surface symptoms Reaction
0 0% No symptoms of infection High resistance (HR)
1 1-12.5% Very weak infection Resistance (R)
2 13 - 25% Weak infection Tolerance (T)
3 25.5 - 50% Moderate infection Susceptible (S)
4 50.5 – 100% Very severe infection High susceptible (HS)
Data were recorded on individual 10 plants of each inbred lines for
main stem length (cm), average fruit diameter (cm), average fruit length
(cm), average fruit weight (g), number of fruits/plant, sex ratio, earliness,
and total yield/plant (kg).
62 Egypt. J. of Appl. Sci., 36 (3) 2021
Observations were recorded on various characters and subjected to
statistical analysis. Collected data were subjected to analysis of variance
(ANOVA) using Statistix 8 software version 8.0 (2003) and correlation
was also determined. Genotypic coefficient of variation (GCV),
phenotypic coefficient of variation (PCV), and environmental coefficient
of variation (ECV) were calculated according to (Sivasubramanian and
Menan 1973) and heritability (h2) was calculated according to Johnson
et al (1955).
RESULS AND DISCUTIONS
Evaluation cucumber inbred lines for powdery mildew resistance:
Data obtained on the reaction of snake cucumber inbred lines
evaluated for powdery mildew resistance under artificial infection
conditions on green house in 2015 and presented in Table (3) and Fig.(1).
Among 15 inbred lines cultivated L17 showed completely free from
infection, this is meaning it is high resistance based on the five categories
according to (James 1971). L12, L19, L20, L23, L24 and L27 showed
low infection (resistant) . On the other hand the other inbred lines varied
between tolerant (L14 and L25), susceptible (L16 and L18) and four
inbred lines showed highly infection, (L4, L21, L22 and L26) i.e. these
inbred lines are highly susceptible to powdery mildew.
Table 3. Quantitative genetic parameters of powdery mildew in
snake cucumber inbred lines.
Inbred lines Mildew% Reaction
L4 61.4 HS
L12 3.3 R
L14 23.3 T
L16 38.2 S
L17 0.9 HR
L18 25.8 S
L19 2 R
L20 3.7 R
L21 87 HS
L22 78.4 HS
L23 2.7 R
L24 3.7 R
L25 23.3 T
L26 93 HS
L27 6.6 R
LSD 2.7
Egypt. J. of Appl. Sci., 36 (3) 2021 63
Fig. 1: powdery mildew resistance and Fruit quality differences of the
parental melon genotypes.
64 Egypt. J. of Appl. Sci., 36 (3) 2021
Mean performance:
Means of 8 horticultural traits for 15 snake cucumber inbred lines in
Tables (4 and 5). Differences among inbred lines for all studied characters
were significant, indicating wide diversity among these inbred lines
1- Main stem length
Data showed that inbred lines L12 and L22 had the highest values
of main stem length in both two seasons (269.2, 272.0, 269.9 and 272.7
cm, respectively), with significant differences with the other inbred lines
in 2016 and 2017. The L4 was lowest of main stem length the two
seasons (184.5 and 187.3 cm) with significant differences with the other
inbred lines.
Table 4. Means performance of studied snake cucumber inbred lines.
Inbred
lines
Main stem length (cm)
Average fruit
diameter (cm)
Average fruit length
(cm)
Average fruit
weight (g)
2016 2017 2016 2017 2016 2017 2016 2017
L4 184.5 187.3 **6.77 **7.57 21.4 22.2 130.4 133.2
L12 **269.2 **272.0 4.53 5.13 51.2 51.8 182.9 184.5
L14 252.9 255.7 4.53 4.93 **73.4 **73.8 **376.4 **379.0
L16 240.8 243.6 4.57 5.37 61.7 62.5 324.5 326.1
L17 214.4 217.2 4.70 5.10 42.2 42.6 231.0 232.6
L18 253.6 256.4 5.10 5.70 **73.2 **73.8 318.2 321.0
L19 248.8 251.6 4.93 5.73 67.5 68.3 271.1 272.7
L20 237.0 239.8 4.60 5.00 64.8 65.2 298.1 299.7
L21 231.7 234.5 5.63 6.43 34.9 35.7 207.5 210.3
L22 **269.9 **272.7 4.50 5.10 **76.8 **77.4 308.1 315.9
L23 228.4 231.2 5.37 5.77 35.9 36.3 171.0 173.8
L24 236.1 238.9 4.43 5.23 61.4 62.2 237.4 239.0
L25 232.9 235.7 6.17 6.57 41.4 41.8 249.5 251.1
L26 217.1 219.9 4.43 5.03 64.2 64.8 300.4 303.2
L27 225.0 227.8 4.17 4.57 48.8 49.23 183.0 184.6
Lsd 9.5 10.3 0.40 0.60 4.9 5.32 28.3 28.9
These results agreement with (Youssef 2018) who evaluated three
local cultivars of snake cucumber and their generations and found values
of main stem length ranged from 167.12 to 272.31 cm.
2- Fruit diameter:
Data obtained on the trait fruit diameter of 15 snake cucumber
inbred lines are presented in table (4). Data showed that only L4 gave the
highest values of fruit diameter in both seasons (6.77 and 7.57 cm,
respectively), with significant differences with the other inbred lines in
2016 and 2017. The lowest fruit diameter was obtained on L27 (4.17 and
4.57 cm) in both seasons, respectively. Youssef (2018) reported in his
studied on snake cucumber that values of fruit diameter ranged from
3.13 to 4.53 cm.
3- Fruit length:
Data obtained on the trait fruit length are illustrated in table (4)
The results obtained that the 3 inbred lines (L14, L18 and L22) gave fruit
Egypt. J. of Appl. Sci., 36 (3) 2021 65
length above 70 cm in both two seasons. On the contrary, L4 gave the
shortest fruit length on both season (21.4 and 22.2 cm,
respectively).Youssef (2018) reported in his studied on snake cucumber
that values of fruit diameter ranged from 28.53 to 36.84cm.
4- Fruit weight:
Data obtained on fruit weight are illustrated in table (4). L14, L18
and L22 gave fruit weight above 300 g in both two seasons, but L14
gave the heaviest fruit weight in both two seasons (376.4 and 379.0 g,
respectively). The lightest fruit weight was obtained in inbred line L4
(130.4 and 133.2 g) in both seasons respectively. it could be concluded
that inbred lines L14, L18 and L22 had the highest value of fruit length,
diameter and weight.
5- Number of fruits per fruit
Number of fruits per plant of the studied inbred lines had wide
range from 4.7 to 15.80 fruits (Table 5) in both seasons. The inbred lines
L19, L23 and L37 had the highest number of fruits per plant with
significant differences with the other inbred lines in 2016 and 2017. on
the other hand, L12, L18, L22 and L26 had the lowest number of fruits
per plant with significant differences with the other inbred lines in 2016
and 2017.
Table 5. Means performance of studied snake cucumber inbred lines.
Inbred lines
No. fruits/plant Sex ratio Earliness Total yield (kg/plant)
2016 2017 2016 2017 2016 2017 2016 2017
L4 11.4 12.23 **0.103 **0.108 **56.8 **59.6 1.50 1.63
L12 4.7 5.27 0.020 0.025 46.6 48.2 0.90 0.97
L14 8.2 8.63 0.050 0.054 52.1 54.7 **3.13 **3.27
L16 10.6 11.37 0.060 0.066 48.7 50.3 **3.37 **3.71
L17 11.6 11.97 0.057 0.061 52.8 54.4 2.67 2.78
L18 4.8 5.40 0.040 0.043 51.9 54.7 1.53 1.73
L19 **15.0 **15.80 0.057 0.062 49.1 50.7 **4.07 **4.31
L20 7.8 8.23 0.033 0.039 51.7 53.3 2.30 2.47
L21 11.8 12.60 0.060 0.061 50.2 53.0 2.47 2.65
L22 4.9 5.50 0.027 0.031 50.0 52.8 1.37 1.54
L23 **13.0 **13.40 0.073 0.078 49.2 52.0 2.20 2.33
L24 5.0 5.80 0.027 0.033 46.9 48.5 1.20 1.39
L25 9.9 10.30 0.030 0.034 49.6 51.2 2.47 2.59
L26 4.9 5.47 0.047 0.055 49.5 52.3 1.47 1.66
L27 **13.0 **13.40 0.073 0.078 47.4 49.0 2.37 2.47
Lsd 2.3 2.60 0.009 0.012 2.2 2.8 1.02 1.07
6- Sex ratio:
Sex ratio ranged from 0.020 to 0.108 in both seasons. L4 gave the
highest value of sex ratio (0.103 and 0.108) in both seasons respectively.
L12, L22 and L27 gave the lowest value of sex ratio (ranged between
66 Egypt. J. of Appl. Sci., 36 (3) 2021
0.20 to 0.033) in both seasons respectively, with significant differences
with other inbred lines.
7- Earliness:
Earliness in the studied 15 snake cucumber inbred lines ranged
from 46.6 to 59.6 days (Table 5) in the two seasons of 2016 and 2017.
Earliness was clear in L12 (46.6and 48.2 days), L16 (48.7 and 50.3
days), L24 (46.9 and 48.5 days) and L27 (47.4 and 49.0 days) in both
seasons of study. L4 was the Latest value obtained with L4 in both
seasons (56.8 and 59.6 days).
8- Total yield/plant:
Data obtained on the total yield per plant are illustrated in table
(5). The results indicated that evaluation of inbred lines based on higher
yield per plant ranged from (0.90 to 4.07 kg) and (0.97 to 4.31 Kg) in
both seasons respectively, L19 (4.07 and 4.31 Kg) as the top ranking
inbred line without significant differences with L14 in both seasons. L12
had the lowest values of total yield per plant in two season. Youssef
(2018) reported in his studied on snake cucumber that values of Total
yield/plant ranged from 4.40 to 7.51 kg.
Genetic studies
Improvement of snake cucumber depends on the nature and
magnitude of genetic variability in the population. Genetic variability
studies provide basic information regarding the genetic properties of the
population. The extent of variability presented in snake cucumber
cultivars was measured in terms of phenotypic variance (ϭ2ph),
genotypic variance (ϭ2g), phenotypic coefficient of variation (PCV),
genotypic coefficient of variation (GCV) and heritability (h2b) as shown
in Table 6.
- PCV and GCV
Estimates of phenotypic variance (VP) were larger than the
corresponding genotypic variance (VG) for all examined traits.
Moreover, close estimates of phenotypic coefficient of variation (PCV)
and genotypic coefficient of variation (GCV) were noted in all
characters, which imply the contribution to phenotypic expression of
these characters are mostly due to genetic factors, while the
environmental ones were not great importance. Characters having a high
genotypic coefficient of variation indicate a high potential for effective
selection. These findings are in agreement with those reported by Rakhi
and Rajamony (2005), Mehta et al. (2009), Ibrahim (2012), Potekar et
al. (2014) and Janghel et al. (2018).
Egypt. J. of Appl. Sci., 36 (3) 2021 67
Greater variability ensures better changes of producing new
desirable forms. Genotypic coefficient of variation (GCV) and
phenotypic coefficient of variation (PCV) were computed for nine
studied characters on 15 snake cucumber inbred lines (Table 6). The
GCV ranged from 8.65% (earliness) to 74.24% (sex ratio). The PCV for
different characters ranged from 9.03% (earliness) to 76.84% (sex
ratio).High amount of fixable variation in watermelon characters has
been reported by (Youssef 2018). In the present study, high estimates of
both GCV and PCV were registered for the studied traits, viz., NF (64.62
and 68.16 % respectively), SX (74.24 and 76.84% respectively), and TY
(64.00 and 69.69% respectively) which suggest greater phenotypic and
genotypic variability among the accession and responsiveness of the
attributes for making further improvement by selection.
Moderate estimates of GCV and PCV were registered for the
traits Fruit length (52.42 and 52.69% respectively) and fruit weight
(46.28 and 46.78% respectively).
Low estimates of GCV and PCV were registered for the traits
viz., stem length (15.90 and 16.08% respectively), Fruit diameter (25.05
and 25.50% respectively) and earliness yield per plant (8.65and 9.03%
respectively), which indicated that these traits were less affected by
environment. Indiresh (1982) reported similar results in bitter gourd.
This suggests that these characters may be less influenced by
environment which is agreement with the findings of (Tomer et al. 2008)
in muskmelon.
- Heritability
In the present study, almost all the characters exhibited high
heritability value which ranged from 84.33 to 98.96% table (7). High
heritability values obtained for all traits in the present study suggest that
these traits may generally be governed by additive gene action and hence
the phenotype would provide a fairly reliable measure of the inbred line
which provides scope for selection based on the phenotypic performance
In general, we can notice that the differences between phenotypic
and genotypic variance for all studied traits were low. In other words, the
large portion of phenotypic variance (Vp) was due to the genetic variance
(Vg). Consequently, estimated broad-sense heritability showed high
values for these traits, indicating that the observed significant phenotypic
differences among the studied inbred lines are of genetic nature and there
are small environmental effects on the phenotypic variation. Therefore,
68 Egypt. J. of Appl. Sci., 36 (3) 2021
these characters can be improved through selection based on phenotypic
observations in early segregating generations in watermelon germplasm.
Table 7. Estimation of PCV, GCV, heritability and genetic advance
as per cent of mean for various characters in snake
cucumber.
No. Characters VE VG VP GCV% PCV% h2 (%)
1 SL 32.17 1409.14 1441.31 15.90 16.08 97.77
2 FD 0.06 1.54 1.60 25.05 25.50 96.51
3 FL 8.64 819.05 827.69 52.42 52.69 98.96
4 FW 287.30 13455.80 13743.10 46.28 46.78 93.33
5 NF 3.90 34.61 38.51 64.62 68.16 89.87
6 SX 0.0001 0.0014 0.0015 74.24 76.84 93.33
7 EA 1.70 18.83 20.53 8.65 9.03 91.73
8 TY 0.37 1.98 2.35 64.00 69.69 84.33
SL= stem length, FD=Fruit diameter, FL=Fruit length, FW= fruit weight, NF=Number of fruits per
plant, SX= sex ratio, EA=earliness and TY=Total yield per plant
CONCLUSION
Results showed that L19 ( resistant, no bitterness, high number
fruit per plant, high total yield and marketable fruit characters ) and L24
( resistant, no bitterness, earliness and marketable fruit characters) were
the best inbred lines which can suggested to be introduction in breeding
programmer to produce new variety.
REFERENCES
AbdEl-Salam, M.M.M. ; I.S. El-Demrdash and A.H. Hussein (2009).
Phenotypic stability analysis, heritability and protein patterns of
snake cucumber genotypes. 6th International Plant Breeding
Conference, Ismailia, Egypt, 3-5 May, 791-798.
AbdEl-Salam, M.M.M. ; I.S. El-Demardash and A.H. Hussein
(2010). Phenotypic stability analysis, heritability and protein
patterns of snake cucumber genotypes. J. of American Sci;
6(12):503-507.
Abdel-Ghani, A.H. and A. Mahadeen (2014). genetic variation in
snake melon (Cucumis melo var. flexuosus) populations from
Jordan using morphological traits and RAPDs. Jordan Journal of
Agricultural Sciences, 10(1):96-119.
Burton, G.W.(1952). Quantitative inheritance in grasses. Proc. Sixth Int.
Grassland Congr. 1:277-283.
Floris, E. and J. M. Alvarez (1991). Inheritance of resistance to
phaerotheca fuliginea in two local melon cultivars. Acta Hort.,
488: 119-124.
Egypt. J. of Appl. Sci., 36 (3) 2021 69
Ibrahim, E.A. (2012). Variability, heritability and genetic advance in
Egyptian sweet melon (Cucumis melo var. aegyptiacus L.) under
water stress conditions. International J. of Plant Breed and
Genet. 6:238-244.
Indiresh, B. T. (1982). Studies on Genotypic Variability in Bitter Gourd
(Momordicacharantia L.) M.Sc. (Agri.) Thesis abstr. 8 (1):
Univ. Agri. Sci. Bangalore.
James, W.C. (1971). A mannual of assessment keys for plant disease.
Canada Dep. Agric. Publication No. 1458.
Janghel A.K. , J. Trivedi, D. Sharma, Y. Lodhi and L. Kand Kumar.
(2018). Genetic variability in muskmelon (Cucumis melo L.)
Under Protected Condition. Int. J. Curr. Microbiol. App. Sci., 6:
211-217.
Johnson, H.W. ; H.F. Robinson and R.E. Comstock (1955) Estimates
of genetic and environmental variability in soybeans. Agron. J;
47:314-318.
Kenigsbuch, D. and Y. Cohen (1989). Independent inheritance of
resistance to race 1 and 2 of Sphaerotheca fuliginea in
muskmelon. Plant Dis., 73: 206—208.
Mehta, R. ; D. Singh and M.K. Bhalala (2009). Genetic variability,
heritability and genetic advance in muskmelon (Cucumis melo
L.). Veg. Sci., 36:248-250.
Mohamed, T.Y. ; T.M. Elamin ; A.M. Baraka ; A.A. El Jack and
E.A. Ahmed (2010) Variability and Correlation among
morphological, vegetative, fruit and yield parameters of snake
melon (Cucumis melo Var.flexuosus). Cucurbit Genetics
Cooperative Report. 2010-2011;33-34: 32-35.
Mohammed, S.A. ; R.M. Jamous ; M.J. Shtaya ; O.B. Mallah ; I.S.
Eid and S.Y. AbuZaitoun (2015). Morphological
characterization of snake melon (Cucumis melo var. flexuosus)
populations from Palestine. Genet Resour Crop Evol.; 64:7–22.
Nuñez, P. ; G. Hector ; L. Gomez ; O. A. Miguel ; G. Neftali ; L. G.
Rebecca and D. J. Cantliffe (2008). Melon fruits: genetic
diversity, physiology, and biotechnology features. Critical
Reviews in Biotechnology, 28 (1): 13-55.
Nwangburuka, C.C. and O.A. Denton (2012) Heritability, character
association and genetic advance in six agronomic and yield
related characters in leaf Corchorus olitorius. Int. J. Agric. Res.,
7:367-375.
70 Egypt. J. of Appl. Sci., 36 (3) 2021
Ogunniyan, D.J. and S.A. Olakojo (2015) Genetic variation,
heritability, genetic advance and agronomic character
association of yellow elite inbred lines of maize (Zea mays L.).
Niger. J. Genet., 28: 24-28.
Potekar, S.V. ; P.K. Nagre and S.N. Sawant(2014). Genetic variability
study in muskmelon (Cucumis melo L.). International J. Tropic.
Agric.,32(3-4):349-351.
Rakhi, R. and L. Rajamony (2005). Variability, heritability and genetic
advance in landraces of culinary melon (Cucumis melo L.). J. of
Tropical Agriculture. 43(1-2): 79-82.
Singh, R.S. (1987): Diseases of Vegetable Crops. Oxford and IBH
Publication, New Delhi, India.
Sivasubramanian, S. and M. Menan (1973). Heterosis and inbreeding
depression in rice. Madras Agric. J., 60: 1139.
Splittstoesser, W.E. (1990) Vegetable growing handbook. Organic and
traditional methods. 3id Ed. Chapman & Hall, NY, USA.
Tang, R. ; X. Zhang ; T. Hu and K. Cao (2003). Control Effect of the
Extracts from Rheum palmatum on Powdery Mildew of
Cucumber. J. Anhui. Agric. Univ., 30(4): 363 - 366.
Tomer, R.S. ; G.U. Kulkarni ; D.K. Kakade ; A.D. Patel and R.R.
Acharya (2008). Genetic variability, correlation and path
analysis in musk melon (Cucumis melo L.). Asian J. Hort., 3 (1):
158-161.
Wheeler, B.E. (1969) An Introduction to Plant Diseases. John Wiley and
Sons, London.
Yadav, Y.C. ; S. Kumar and R. Singh (2012). Studies on genetic
variability, heritability and genetic advance in cucumber (Cucumis
sativus L.). Hort. Flora Research Spectrum, 1(1): 34-37.
Youssef, M.M. (2018): Genetic Improvement of Yield and Fruit Traits in
Snake Cucumber (Cucumis melo var. flexuosus L.) by Individual
Selection. Asian Journal of Biotechnology and Genetic
Engineering 1(2): 1-10, Article no.AJBGE.43185.
التباين الو ا رثي ونسبة التوريث والارتباط في القثاء
أيمن محمد عبدربه 1، محمود محمد رمضان 2، مصطفي عبد الفتاح 3
1قسم بحوث تربية الخضر - معيد بحوث البساتين - مرکز البحوث الز ا رعية
2قسم آفات ووقاية نبات-الشعبة الز ا رعية- مرکز البحوث الز ا رعية
3قسم الخضر-کمية الز ا رعة-جامعة القاىرة
أجريت ىذه الد ا رسة بمعيد بحوث البساتين – مرکز البحوث الز ا رعية – خلال الفترة من
6102 إلى 6103 و ذلک بيدف د ا رسة صفة المقاومة لمبياض الدقيقي بالإضافة الي بعض
الصفات الإقتصادية في القثاء وىى صفة طول الساق الرئيسى, متوسط قطر الثمرة, متوسط
Egypt. J. of Appl. Sci., 36 (3) 2021 71
طول الثمرة, متوسط وزن الثمرة, النسبة الجنسية , التبکير, عدد الثمار بالنبات والمحصول الکمى
لمنبات. وقد إستخدمت فى الد ا رسة 01 سلالة مرباة داخميا وقد اظيرت النتائج وجود تباين واسع
واختلافات معنوية عالية لمصفات محل الد ا رسة. وت ا روحت قيم کلا من معامل التباين ال و ا رثي
32.47 ( عمي التوالي , وتظير ىذه -1.10 ,37.67- ومعامل التباين المظيري ما بين ) 4.21
القيم العالية انو يمکن الاختيار بين السلالات بسيولة. وت ا روحت قيم درجة التوريث في المستوي
54.52 %( , القيم العالية لمتوريث عمي المستوي العريض اظير – العريض ما بين ) 47.00
ان الصفات قابمة لمتوريث بدرجة عالية وانو يمکن الاختيار فيما بينيا بسيولة. و تم اختيار
67 کأفضل السلالات المتفوقة في صفات المقاومة لمبياض الدقيقي وعدم L 05 و L السلالتين
وجود م ا ررة بالإضافة لجودة الصفات المحصولية والثمرية لاستکمال برنامج التربية لإنتاج ىجن
قابمة لمتسويق.
72 Egypt. J. of Appl. Sci., 36 (3) 2021