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Isozymic Variation in Radish (Raphanus
sativus L.)
for Identifying Self-Incompatible Line
--N A Ivy, --M S Biswas, --G Rasul,
--T Hossain, --M A K Mian
The experiment was conducted to characterize 78 radish genotypes using esterase and peroxidase isoenzymes.
The results of the experiment reveal a wide range of diversity among the genotypes based on their esterase and
peroxidase isoenzyme banding patterns. Five bands at different relative front (Rf) values varying from 0.06 to 0.56 were
observed in peroxidase enzyme system and formed 10 zymotypes. Zymotype
P1 was the most frequent which includes
26.92% of the total genotypes. The lowest frequency of 2.56% was observed in the zymotype
P10. Bands 3 and 4 consist of same frequency (23.31%) of the genotypes at Rf values 0.20-0.30 to 0.30-0.50. It was also found that there was no
common band for all the genotypes. Thus, the genotypes have a wide range of genetic variation. On the other hand,
13 electrophoretic zymotypes
(P1-P13) were observed in the esterase enzyme system formed by 13 bands at different
Rf values varying from 0.04 to 0.93. It appeared that electrophoretic zymotype
P6 was the most frequent (25.64%) and zymotype
P13 was the least frequent (2.56%). The zymotype
P11 had maximum number of bands. From the
distribution of esterase bands among the radish genotypes, it was observed that band 3 had the most frequency of
18.75%, followed by bands 2 and 4 which had the same frequency of 16.67% among all the genotypes. A dendogram, based
on the two polymorphic enzyme activities of all the genotypes, was classified into eight major clusters, designated as I,
II, III, IV, V, VI, VII and VIII. The highest number of 21 genotypes was found under the cluster number I that
represented 27% of the total genotypes, followed by cluster VI which contained 17 genotypes. The lowest number (4) of
genotypes was found under cluster VII, followed by cluster III which contained 5 genotypes. The results indicate that
zymotypes of higher frequency are the representative of less variation. The lower frequency of the germplasm in
different zymotypes indicated higher variation among the genotypes.
© 2010 IUP. All Rights Reserved.
Changes in the Pattern of Superoxide Dismutase (SOD)
and Malate Dehydrogenase (MDH) in Response
to Heat Stress Conditions in Wheat
--Sameena Sheikh, --R K Behl,
--Ashwani Kumar, --A K Chabra
High temperature during grain filling stage is the single most important factor that limits the productivity of
wheat. Therefore, studies on enzymes that are implicated on thermotolerance during grain development stages are
important. Nine homozygous genotypes of wheat (Triticum aestivum
L. em. Thell)PBW 343, WH 283, WH 542, PBW 435,
UP 2,565, UP 2,425, EIGN1, EIGN8 and Raj 3,765and six F1 crossesPBW 343
´ WH 283, PBW 343 ´ WH 542, PBW 343
´ PBW 435, UP 2,565 ´ UP 2,425, EIGN 1
´ Raj 3,765 and EIGN 8 ´ UP 2,425were grown in the experimental
areas of CCSHAU, Hisar, under normal- and late-sown environments. Changes in protein profiles, based on the
banding pattern of isozymes for Superoxide Dismutase (SOD) and Malate Dehydrogenase (MDH), were studied. Based on
the banding pattern of SOD isozyme, three isomers of different Rf values, 0.49, 0.75 and 0.85 in normal-sown and
0.84 and 0.87 in late-sown (high temperature condition during grain filling stages), were observed. The band of Rf
value 0.75 was found only in the case of EIGN 1 of very dark intensity and light dark intensities in Raj 3,765 and EIGN 8,
while in the case of F1s, very dark intensity band in PBW 343
´ WH 542 and light dark intensities in PBW 343
´ PBW 435 and UP 2,565 ´ UP 2,425, were observed. Based on the banding pattern of MDH, 4 bands of Rf values, 0.55, 0.67, 0.69
and 0.75 in normal-sown and three bands of Rf values 0.55, 0.75 and 0.82 for late-sown conditions, were observed.
The Rf value of 0.82 band was observed only in the case of late-sown among the genotypes PBW 435 (light intensity),
UP 2,425, EIGN 1 and EIGN 8 (all three with dark intensity) and F1 crosses PBW 343
´ WH 283 (very light intensity, PBW 343
´ WH 542 dark intensity), PBW 343 ´ PBW 435 (dark intensity) and UP 2,565
´ UP 2,425 (light intensity). The implications of the results are discussed in the light of the role of enzymes in terminal heat stress in wheat.
© 2010 IUP. All Rights Reserved.
An Analysis of Genetic Diversity Among Indian Coldwater Fishes
(Pisces: Cyprinidae) Using RAPD Markers
--G K Sivaraman, --A Barat, --S Ali,
--N N Pandey, --K D Joshi, --P C Mahanta
The present investigation aims to study the genetic relatedness among the coldwater fish species and construction
of phylogenetic relationships among them. Eleven random primers were employed to screen for RAPD markers in
the most commonly available coldwater fish species of Uttarkhand region, viz.,
Tor putitora, Schizothorax
richadrsonii, Raiamas bola and Garra
species. The sizes of the amplified products were from 200 to 5,000 bp in all the fish
species with all the primers employed. Total 188 bands were scored with the 11 primers employed, with the average
numbers of bands scored being 3.54 ± 0.72, 5.18
± 0.69, 3.64 ± 0.58 and 4.73 ± 0.78 in
Tor putitora, S. richadrsonii, R.
bola and Garra species respectively. The maximum numbers of scorable bands were obtained with primer OPA-03 primer in
Tor putitora (08 ± 0.71), Schizothorax
richadrsonii (08 ± 0.71), Raiamas
bola (07 ± 0.71) and Garra species (05
± 0.71), and minimum numbers (1 to 3) of amplified fragments were observed with primer OPA 05. Higher proportion of
polymorphic bands were produced by OPY02 (7.5%) and NUSZG4 (5.75%) primers among these fish species. The highest
genetic distances were observed between T.
putitora and R. bola (0.60), followed by
T. putitora with Garra species (0.52), and
the least genetic distance was observed between the
S. richardsonii and Garra species (0.36), followed by
T. putitora and S. richardsonii (0.43). The phylogenic tree was constructed using TDRAW V1.4 software package, which revealed the
T. putitora with S. richardsonii and
Garra species with R. bola forming a separate monophyly.
© 2010 IUP. All Rights Reserved.
Genetic Variability and Association for Floral, Quantitative and
Quality Traits in Rice (Oryza sativa L.)
--M Umadevi, --P Veerabadhiran
Genetic variability and correlation studies were conducted on 110 genotypes of rice. Estimates of
genotypic variance, phenotypic variance, genotypic coefficient of variation, phenotypic coefficient of variation, heritability
in broad sense, genetic advance and association for grain yield with floral, quantitative and quality characters
were computed. The characters, viz., stigma exsertion percent, anther length, outcrossing rate, number of grains
per panicle, single plant yield, volume expansion ratio, gel consistency, gelatinization temperature and amylose
content possessing high GCV, heritability and genetic advance ,were effectively used in selection. The single plant yield
had highly significant and positive association with the number of productive tillers per plant, panicle length,
number of secondary branches per panicle, 100 grain weight and number of grains per panicle.
© 2010 IUP. All Rights Reserved.
Component Analysis of Upland Cotton
(Gossypium hirsutum L.) in Different Environments
--S K Kaushik,
--C J Kapoor
The genetic makeup of an attribute comprises additive, dominance and epistasis variance. The information of
the relative degree of genetic variance components is fundamental in the selection of appropriate breeding
methodologies. The diallele analysis is the quickest method to enable predictions to be made based on early generations, which
could greatly increase the efficiency of breeding programs. Component analysis revealed that additive-dominance
model fitted only for number of sympodial branches per plant in both the generations under all the three environments.
The present study indicates the preponderance of dominance components for inheritance of this character.
Heritability values in the narrow sense for this character varied from low (17.50 % in
E2 F1) to moderate (46.58% in
E2 F2). Since both additive and non-additive types of gene actions were present in different proportions, reciprocal recurrent
selection is suggested for the improvement of the character.
© 2010 IUP. All Rights Reserved.
Cryopreservation of Medicinal Plant Systems:
Progress, Problems and Prospects
--P E Rajasekharan,
--R Prakashkumar
Cryopreservation (liquid nitrogen_196 °C) represents the only safe and cost-effective option for
long-term conservation of plant germplasm. Classical cryopreservation techniques, which are based on
freeze-induced dehydration, are suitable for freezing undifferentiated cultures and apices of cold-tolerant species.
New cryopreservation techniques, which are based on vitrification, are successfully employed with all explants,
including cell suspensions and calluses, apices, and somatic and zygotic embryos of temperate and tropical species
of medicinal plants. The development of cryopreservation protocols is significantly more advanced for
vegetatively-propagated species than for recalcitrant seed species. Technology has been developed for
long-term cryopreservation of nuclear genetic diversity in the form of pollen. Besides the already existing role of
pollen cryobanks in breeding, there are many promising applications which
have come into focus with the recent advances in allied bioscientific areas.
There are a growing number of examples where cryopreservation is employed on
a large-scale for different types of materials, including seeds with orthodox and intermediate storage
behavior, dormant buds, pollen, biotechnology products, and apices sampled from
in vitro plantlets of
vegetatively-propagated species. In addition to germplasm conservation, cryopreservation also ensures genetic stability and retention
of biosynthetic potential. Various explants have been used for cryopreservation of medicinally important
plants. The present review takes stock of the
developments in this area with a special reference to medicinal plants.
© 2010 IUP. All Rights Reserved.
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