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Studies on Some Important Floral Traits of CGMS Lines of Hybrid Rice
(Oryza sativa L.)
-- M Umadevi, P Veerabadhiran, S Manonmani and P Shanmugasundaram
Thirty CGMS lines and their respective maintainer lines were evaluated for floral characters. The traits studied
were days to 50% flowering, glume angle, panicle exsertion percentage, stigma exsertion percentage, pollen
sterility percentage, awning, spikelet fertility percentage and out crossing percentage. All the genotypes showed
significant variation for the traits studied. Out of 30 CGMS lines, 15 CGMS lines were found to be completely pollen sterile,
while others showed spikelet fertility ranging from 0.25 to 1.30%. The CGMS linesIR 72081A, IR 75596A, IR 75601A,
IR 75608A, IR 80154A, IR 80559A, CRMS 32A, APMS 6Awere found to be promising for the characters of
glume angle, panicle exsertion percentage, stigma exsertion percentage, pollen sterility percentage, natural out
crossing rate and medium duration. These CGMS lines may be further studied and utilized for three-line hybrid rice
production technology.
© 2009 IUP. All Rights Reserved.
Phenotypic Analysis of Anther and Pollen
in Diversified Genotype of Barnyard Millet
(Echinochloa frumentaceae) Floral Characters
-- A Nirmalakumari and M Vetriventha
The paper investigates the scope of variability in germplasm collection of barnyard millet
(Echinochloa frumentacea) for its crop improvement and evolution of new high yielding varieties. This is the quickest growing millet and
it produces a crop in a period of six weeks. It is grown in India, Japan and China as a substitute for rice when the
rice crop fails. The present investigation is to compare the wild type barnyard millet with the normal type with respect
to morphological characters that delineate the three types in two groups is related to the differences in its days
of flowering, plant height (cm), total number of tillers, total productive tillers, ear length (cm), days to maturity,
anther length, pollen diameter and fertility percentage were studied. Normal cultivated types are: small flower size,
early hours of flowering, short viability of pollen, non-availability of pollen grain and slight opening of flowers that too
in short period, while these new types of germplasm IEC 566 and IEC 566/2 produced abundant pollen grains open
for a long time, protrude enough to do emasculation and collection of pollen grains facilitating emasculation
and crossing. The results indicate that the potential of barnyard millet in enhancing the hybridization work which in
turn will help in genetic analysis, heterotic study and generating more segregants for further barnyard crop improvement.
© 2009 IUP. All Rights Reserved.
Variability Studies in Rice (Oryza
sativa L.) for Salt Tolerance
-- K Seetharam, S Thirumeni and K Paramasivam
An investigation was carried out during 2005-2007 in rice to screen salt tolerant genotypes, estimate the
heritability parameters, association and genetic divergence for nine characters. The characters viz., plant height, total
tillers, productive tillers, panicle weight and single plant yield registered high heritability and genetic advance
indicating possibility of improvement through simple phenotypic selection. The correlation studies of yield-related traits
revealed that panicle weight and spikelet fertility may be given due weightage while selection since they recorded
highly significant positive association with single plant yield under saline alkaline condition. Path analysis revealed that
total tillers, spikelet fertility and panicle weight had direct and significant correlation with single plant yield and
therefore selection based on the same can aid for genetic improvement. The 30 genotypes were grouped into nine and
seven clusters based on Tocher's and Ward's method, respectively, with single plant yield contributing much to the
total genetic divergence. It also indicated that Ward's method is superior to Tocher's method in resolving genotypes
into different clusters. Based on Tocher's method of clustering, intercrossing between genotypes of cluster VII
and cluster IX may throw an array of recombinants in the segregating generations for effective selection under
saline alkaline condition.
© 2009 IUP. All Rights Reserved.
In-Vitro Conservation of Tylophora
indica:
A Threatened Medicinal Plant
-- P E Rajasekharan, S R Ambika and S Ganeshan
A protocol for in-vitro conservation of Tylophora indica (Burm. f.) Merrillan important medicinal planthas
been developed. T. indica plants cultured in MS medium supplemented with 0.54 µM NAA and 4.44 µM BAP produced
5-10 shoots within a period of two months. For in
vitro conservation studies, experiments were carried out in 2-3
week maintained vitroplants under Standard and Reduced Culture Conditions (SCC and RCC). Vitroplants could be
successfully conserved in Full Strength MS Medium (FMS) under SCC for six months without subculture with full potential
to regenerate, producing viable shoots and nodes. The root production remained unaffected due to
conservation, showing high rooting activity in mannitol and low temperature treatments. Preset low temperature regimen
(15 oC and 10 oC) and reduction in media constituents do not appear to favor conservation, although the
former accomplished conservation levels equal to FMS under SCC.
© 2009 IUP. All Rights Reserved.
Genetics of Yield and Other Traits in American Cotton
-- Kaushik S K and Kapoor C J
A half diallel set among 10 parents of hirsutum cotton was undertaken to evaluate combining ability and its
interactions with environments. The experiment was conducted under three environments in a randomized block design,
replicated thrice. ANOVA showed highly significant differences for all the traits studied. All characters except four, i.e.,
monopodia per plant, seeds per boll, seed index and fiber fineness were influenced by the environments. Variance ratio
revealed the preponderance of non-additive genetic variance. Significant general combining ability (gca) and specific
combining ability (sca) x environment interactions were observed for most of the characters. The best general combiners in
all the environments were: C-2602-WIR-6109 for monopodia per plant and seed cotton yield, LH 1861 for bolls
per plant and RS 2115 for seeds per boll. Crosses exhibiting highest sca effects coupled with high per se performance were LH 1836 x H 1123 for plant height, bolls per plant, seed index and seed cotton yield; and PIL 8-5 x RS 2115
for plant height and seeds per boll.
© 2009 IUP. All Rights Reserved.
In-Vitro Antimicrobial Activity of Non-Antibiotic Drugs Against
Pathogenic Fish Isolates
-- Musfiqua Mookerjee, Subhasis Maity and Madhumita Mukherjee
Systematic searches for antibacterial activity among synthetic compounds in the past had shown tricyclic
ring structures to possess diverse functions. In this study, trimeprazine an analgesic compound, trifluoperazine
an antipsychotic drug and promethazine an antihistamine with strong sedative effects were found to possess
significant antibacterial activities against 12 genera of pathogenic bacteria which were isolated from diseased edible
fishes collected from water bodies (bheries) of the east Kolkata wetlands in West Bengal, India. The bacteria isolated
from the diseased fish were identified as belonging to the genera of Staphylococcus, Streptococcus, Shigella and Vibrio were found to be highly sensitive to these compounds. However, other bacteria isolated were moderately
sensitive. The noteworthy finding that emerged from this study was the susceptibility of Pseudomonas spp. towards these drugs where even common antibiotics are almost always ineffective.
© 2009 IUP. All Rights Reserved.
Molecular Characterization of Coimbatore Breed of Sheep
(Ovis aries) in South India
-- P Kumarasamy, S Prema, P Ganapathi, S M K Karthickeyan and P Kanakaraj
A total of 27 microsatellite primer sets specific for sheep were used in the study. The
number
of observed alleles ranged from three to eight with a mean of
6.8890.85 across all loci. The most frequent
number of alleles was five (41%) and the least frequent number of alleles was three, seven and eight (7%). The size of
alleles ranged from 72-220 bp. In total, 143 alleles were observed on 27 loci. The frequency of the alleles ranged
from 0.0166-0.7245. Of the 27 loci, the effective number of alleles ranged from 3.72-6.33. The mean number of
effective alleles was 4.93250.60 across all loci. The Polymorphism Information Content (PIC) values in the present
study ranged from 0.3966-0.8096. Based on the PIC values, it was found that 93% of these markers showed values of
more than 0.5, indicating that these microsatellite markers can be effectively used for molecular characterization
and genetic diversity studies. The results of the X2 test of goodness of fit revealed that the population was in
Hardy-Weinberg Equilibrium (HWE) proportions for 19 microsatellite loci. The remaining eight loci departed from
HWE. The observed heterozygosity ranged from 0.6250-0.8462 with a mean of
0.74040.06 while the expected heterozygosity ranged from 0.7211-0.8422 with a mean of
0.81060.03. Population inbreeding estimate
(FIS) indicates heterozygote deficiency was observed to be 0.0666 with a range from - 0.0063
(OarHH72)-0.2233 (OarJMP29). Though positive
FIS values were observed in 20 loci, they reflect inbreeding in Coimbatore sheep.
The markers used in the study were highly informative and high heterozygosity value is indicative of the higher
amount of genetic variability that can be exploited for their improvement.
© 2009 IUP. All Rights Reserved.
Karyoanalysis Among Diploid Banana
(Musa Species) Accessions
-- Rekha A and S C Hiremath
Banana is known to be one of the important fruit crops. It is also considered as food in many African countries.
The present day cultivated bananas have evolved from two main species of Musa, namely, Musa acuminata and Musa balbisiana. Most of the classifications of the banana cultivars are made based on the morphological
observations. Being a polyploid, parthenocarpic, vegetatively propagated crop, studies on karyomorphological aspects and
breeding are rare. In the present paper, an attempt was made to study the karyotypes of some Musa species and diploid cultivars to understand the karyology and homology of chromosomes. Basic cytological techniques like
fuchsin staining and observations on chromosome number and karyomorphological studies were made. It was
observed that there were differences among the Musa species and cultivars studied in the total chromosome length.
© 2009 IUP. All Rights Reserved.
An Empirical Investigation on Classical Clustering Methods
-- S D Wahi, Sukanta Dash and A R Rao
Five classical clustering methods: four hierarchicalsingle linkage, average-between linkage, average-within
linkage, Wardsand one non-hierarchicalk-meansusing five different distance measures: squared Euclidean, city
block, Chebychev's, Pearson correlation and Minkowski have been compared on the basis of simulated multivariate data
on paddy crop genotypes. The performance of different clustering methods was compared based on the
average percentage probability of misclassification and its standard error. The performance of different hierarchical
clustering methods varied with distance measures used and it was found that squared Euclidean performed best among the
five distances followed by city block distance in majority of cases. Among the five methods,
the Ward's method performed best with least average percentage probability of misclassification followed by
non-hierarchical k-means method irrespective of the sample size. Among the different distance measures used
under hierarchical clustering methods, the squared Euclidean distance showed least average percentage probability
of misclassification followed by city block distance.
© 2009 IUP. Al l Rights Reserved.
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