MSc

In Kerala, jasmine is mostly grown as an ornamental crop in homesteads.
Recently, there is an increase in jasmine cultivation due to its high export potential. In
this scenario, knowledge about the pests and defenders of jasmine and their
eco-friendly management under Kerala condition is highly essential. With this
backdrop, the study entitled “Documentation and management of pests of jasmine,
Jasminum spp.” was carried out at Department of Agricultural Entomology, College
of Agriculture, Vellayani during the period of 2019 to 2021.
The objectives of the study were to document the pests infesting
Jasminum spp., their damage and symptoms, natural enemies associated with the pest
and to develop suitable pest management measures.
The documentation conducted at three districts viz., Thiruvananthapuram,
Kollam and Alappuzha recorded sixteen pests. Jasmine budworm
(Hendecasis duplifascialis Hampson), jasmine leaf webworm
(Nausinoe geometralis (Guenee), Nausinoe perspectata (Fabricius)), shoot webworm
(Margaronia unionalis Hubner), jasmine gallery worm (Elasmopalpus jasminophagus
(Hampson)), blossom midge (Contarina maculipennis Felt), lacewing bug
(Corythauma ayyari Drake), flower thrips (Thrips orientalis (Bagnall)), flea beetle
(Hyphasis sita (Maulik)), grasshoppers (Diabolocatantops pinguis (Stal),
Neorthacris acuticeps (Bolivar)), tortoise beetle (Cassida sp.), leafhopper
(Kolla ceylonica (Melichar)), jasmine bug (Antestiopsis cruciata (Fabricus), moth bug
(Ricania sp.), whitefly (Dialeurodes sp.), mealy bug (unidentified) and red spider
mite (Tetranychus sp.). The grasshoppers (D. pinguis, N. acuticeps) tortoise beetle
(Cassida sp.) and leafhopper (K. ceylonica) were reported for the first time from
Kerala as pest of jasmine.
Natural enemies associated with pests of jasmine were also documented in
which the spiders were prominent predators followed by praying mantis. The spiders
documented were white lynx spider (Oxyopes shweta Tikader), crab spider
(Camaricus sp.), pantropical jumping spider (Plexippus paykulli (Audouin)), heavy
bodied jumper (Hyllus semicupreus (Simon)), two striped jumper
(Telamonia dimidiata (Simon)), flower crab spider (Thomisus lobosus Tikader), grass
cross spider (Argiope catenulata (Doleschall)), long jawed orb-weaver
(Tetragnatha maxillosa Thorell) and banded phintella (Phintella vittata (C. L Koch)).
Apart from spiders, Asian mantis (Hierodula membranacea Burmeister) and praying
mantis (Odontomantis pulchra Olivier) were also documented. Spiders
Camaricus sp., A. catenulate and T. maxillosa were reported for the first time from
Kerala on jasmine. A consolidated documentation of spider and mantid predators
from jasmine ecosystem is first of its kind from Kerala. Pupal parasitoid
Brachymeria nephantidis Gahan and larval parasitoid Apanteles sp. were found
parasitizing on the jasmine leaf webworm, N. geometralis and larval parasitoid
Phanerotoma hendecasiella (Cameron) was found parasitizing on jasmine budworm
H. duplifascialis and jasmine gallery worm E. jasminophagus.
Studies on the biology of H. duplifascialis and N. geometralis were carried out
under laboratory condition. H. duplifascialis had an average of 3.35 + 0.11,
11.15 + 0.08 and 5.25 + 0.10 days of egg, larval and pupal period respectively
whereas N. geometralis recorded an egg, larval and pupal period of 3.35 + 0.11,
10.65 + 0.20 and 6.65 + 0.11 days respectively.
The prophylactic and curative field experiments were conducted at
College of Agriculture, Vellayani for evolving efficient pest management practices. It
was found that the prophylactic treatments with biopesticides, oil based formulation
of Metarhizium anisopliae NBAIR Ma 4 @ 10 mL L-1
and Beauveria bassiana
NBAIR Bb 5 @ 10 mL L-1
caused cent per cent reduction in the population of
C. ayyari at 60 days after planting. The population of H. duplifacsialis was also nil in
these plots. A three and two fold increase in flower yield was recorded for
M.anisopliae and B.bassiana, respectively in comparison to untreated plots. The
treatments were found safe to spider predators also. Among the curative treatments,
chlorantraniliprole 8.8% w/w+Thiamethoxam 17.5 % w/w SC @150g a.i ha-1 was the
best with no pest incidence and also had three-fold increase in mean flower yield
(8.10 g plant -1
) compared to the untreated plots. However, it was not safe to spiders.
Among the biopesticides, oil based formulation of M. anisopliae NBAIR Ma 4
@ 10 mL L-1
and B. bassiana NBAIR Bb 5 @ 10 mL L-1
caused 73 and 67 per cent
reduction in the population of H. duplifascialis and 90 and 89 per cent respectively for
C.ayyari. The mean flower yield in M. anisopliae NBAIR Ma 4 @ 10 mL L-1
and
B. bassiana NBAIR Bb 5 @ 10 mL L-1
treated plots was 2.7 and 2.2 times higher than
that in untreated plots. Both treatments were found safe to spiders.
From the present study, it can be concluded that, of the sixteen pests infesting
jasmine, H. duplifascialis, C. ayyari and C. maculipennis attained the status of major
pests. However, considering the presence of different pests belonging to various
orders on jasmine, pest surveillance is highly recommended in the scenario of area
expansion. The study recorded an extensive spectrum of spiders and parasitoids which
played a key role in preventing the population build-up of pests. Prophylactic
sprayings of oil based formulation of M. anisopliae NBAIR Ma 4 @ 10 mL L-1
or
B. bassiana NBAIR Bb 5 @ 10 mL L-1
can be recommended during the initial
appearance of pests on jasmine and the same can be recommended for curative
management. However, for managing severe incidence of pest, single spray of
Chlorantraniliprole 8.8% w/w+ Thiamethoxam 17.5 % w/w SC @150 g a.i ha-1
can be
recommended.