TY  - BOOK
AU  - Karthika Nair, A S
AU  - Beena Thomas (Guide)
TI  - Genetic diversity analysis of gladiolus genotypes (Gladiolus grandiflorus L.) using molecular markers 
U1  - 660.6 
PY  - 2021///
CY  - Vellayani
PB  - Department of Plant Biotechnology, College of Agriculture
KW  - Plant Biotechnology
KW  - Gladiolus genotypes
KW  - Gladiolus grandiflorus L
KW  - Agarose gel electrophoresis
KW  - Polymorphism
N1  - M Sc
N2  - Characterization of plant genotypes based on crop genetic diversity is important 
for effective usage and conservation. This is generally achieved by either 
morphological tools or molecular tools or by using both. This study entitled “Genetic 
diversity analysis of gladiolus genotypes (Gladiolus grandiflorus L.) using molecular 
markers” was carried out in the Department of Plant Breeding and Genetics, College 
of Agriculture, Vellayani, Thiruvananthapuram during 2020-2021 with an objective 
to analyse genetic diversity in the gladiolus genotypes using ISSR as well as 
morphological markers.
Gladiolus (Gladiolus sp.) is a genus of perennial herbaceous cormous 
flowering plants in the family Iridaceae which is of high economic importance. Fifteen 
varieties of gladiolus including twelve varieties from IIHR, Bangalore and three 
varieties from NBRI, Lucknow were selected for this study. The study was divided 
into two parts- morphological characterization and molecular characterization. 
Morphological characterization was done by analysing both vegetative and 
floral characters. Different tools such as analysis of variance, co-variance, 
correlations, PCA and dendrogram were used for statistically analysing the recorded 
data. The dendrogram divided the genotypes into two principal clusters at a distance 
of 0.10. The major variables that contributed to the clustering of gladiolus genotypes 
were plant height, number of leaves per shoot, length of leaf, width of leaf, internode 
length, number of florets open at one time and number of florets per spike as revealed 
by PCA analysis. 
For molecular characterization using ISSR markers the genomic DNA was 
isolated using CTAB method of DNA isolation with little modifications. Ten ISSR 
primers were used for screening fifteen gladiolus genotypes. After the final PCR with 
selected primers, the amplicons were resolved in 2% agarose gel and polymorphic 
bands were obtained. Primers showed 94.56% polymorphism and the number of bands 
obtained ranged from 3(UBC 857) to 14 (UBC 890) with a mean value of 8.7
polymorphic bands per primer. A total of 87 polymorphic bands were obtained. The 
data analysed using NTSYS PC 2.02 program created a dendrogram, which grouped 
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the genotypes based on Jaccard’s similarity coefficient in which the fifteen genotypes 
were separated into two principal clusters. The first principal cluster consisted of most 
of the genotypes (12 genotypes). The second principal cluster comprised of ‘Arka 
Naveen’, ‘Archana’ and ‘Arka Gold’ with ‘Archana’ as an outlier. In molecular 
characterization, least similarity of 34% was observed between G3 (Arka Sapna) and 
G9 (Archana) whereas, maximum genetic similarity of 82% was observed between 
G6 (Arka Amar) and G10 (Arka Kumkum). The highest morphological similarity was 
also observed between G6 (Arka Amar) and G10 (Arka Kumkum) at a distance of 
0.83 in UPGMA dendrogram based on Jaccard’s coefficient.
Though some similarity in results existed between the morphological and 
molecular tools used for identifying the genetic relationships among selected 
gladiolus varieties in this study, it also revealed that the varieties were grouped as 
separate clusters based on morphological dendrogram. This may be due to the 
dependence of morphological expression on the physiological state of the individual 
plant along with environmental influence. Self-incompatibility, along with the 
outcrossing nature together might have contributed to the high variation observed 
among the gladiolus genotypes. Being a commercial cut flower crop, based on 
different floral parameters considered ‘Arka Sapna’, ‘Arka Nazrana’, Arka Darshan’, 
‘Arka Amar’ and ‘Arka Poonam’ are recommended as the gladiolus genotypes that 
showed best performance in Kerala conditions
UR  - https://krishikosh.egranth.ac.in/handle/1/5810190084
ER  -