MSc

The present study titled “Progeny testing and genetic diversity analysis in plus
trees of Melia dubia Cav.” was carried out from 2020 to 2021 with the objective of
progeny evaluation in 25 half sib plus trees identified from different part of Kerala,
by studying the growth performance of its seed progeny planted at college of forestry
germplasm field. The study also includes exploring the genetic diversity of these 25
plus tree seed progenies along with analysing the caryophyllene content, one of the
economically important phytochemical compounds present in M. dubia.
The plus tree seed progeny differed significantly in morphological traits like
height, collar girth, volume and physiological parameters like photosynthetic and
transpiration rate, stomatal conductance, chlorophyll content and relative water
content. The progeny FCV-MD-03 of Tholpetty in Wayanad district performed better
in growth parameters viz., height (5.61 m), collar girth (0.42 m) and tree volume of
(0.017 m3
). The variability study indicated that the morphological trait (volume) and
physiological trait (stomatal conductance) exhibited higher PCV and GCV. From the
heritability estimation it was observed that the most heritable morphological trait was
collar girth followed by the plant height. For the physiological parameter,
transpiration rate (0.91) was the most heritable trait followed by the chlorophyll
content. These morphological and physiological traits were positively correlated
implicating the significance of physiological parameters as source to identify better
progeny. Path analysis on morphological trait has showed that the collar girth had the
highest positive direct effect on the plant volume.
Genetic variation study in 25 plus tree progenies using ISSR primer produced
164 amplicons which estimates viz., percentage of polymorphism (68%),
polymorphism information content (0.70 to 0.83), Nei’s gene diversity (31%). The
dendrogram obtained by using UPGMA classified the 25 accession of M. dubia into
2 distinct clusters. Cluster I constitute population from Wayanad and the rest of the
136
population in cluster II. Based on the genetic variation observed, superior seed
sources can be identified and tree improvement programme could be developed for
the conservation and further development of M. dubia.
Standardization of HPLC for the quantification of caryophyllene phytochemical
in M dubia was studied. Significant variation was observed for the total caryophyllene
content for the different accession of M dubia seed progeny. The maximum quantity
was observed in FCV-MD-08 (16.4 %) of Pothundy in Palghat district followed by
FCV-MD-3 of Tholpetty in Wayanad.