Inducing Resistance in Sesamum Accessions Against ... 285
wider areas. In spite of this, many cultivars were
reported promising at specific areas by workers
(Tables 1 and 2 ).
In addition to the above, under the All India
Coordinated Research Project on Oilseeds pro-
gram being conducted by Indian Council of Ag-
ricultural Research many varieties/cultivars have
been identified (Table 3 ).
Screening Sesame Accessions for
Resistance Against A. catalaunalis
An attempt was made to study the biology, vari-
etal resistance, and management of A. catalau-
nalis during 1989–1991 at Annamalai University,
Tamil Nadu, India (Selvanarayanan 1991 ). Later,
40 sesame lines were gathered from various
sources and screened for field resistance at An-
namalai University Experimental Farm as well as
at a popular sesame tract namely Vridhachalam,
in Cuddalore district, Tami Nadu, India (Vijai
Anandh 2003 ). Subsequently, 140 sesame ac-
cessions were evaluated for resistance against A.
catalaunalis under field conditions during two
seasons at the experimental Farm of Faculty of
Agriculture, Annamalai University, Tamil Nadu,
India (Balaji 2006 ; Balaji and Selvanarayanan
2009 ).
The sesame accessions were sown on the
ridges of 2-m length with a spacing of 30 cm
between the rows and 30 cm between plants.
Ten plants were maintained per replication and
three replications were maintained per accession.
A known susceptible check, namely, SVPR-1
(Vijai Anandh 2003 ) was maintained at one row
for every five rows of the test accessions as well
as two rows around the experimental field as au-
gumentor rows. Recommended agronomic prac-
tices were followed and no pesticide was applied.
The per cent leaf, flower, and capsule damage
caused by A. catalaunalis was recorded respec-
tively from 15, 30, and 50 days after sowing on-
wards till harvest at weekly interval by observing
five plants selected randomly/replication and the
mean percentage damage was computed.
Based on the intensity of damage assessed
on different plant parts, the accessions were cat-
egorized adopting the score chart formulated by
Philip Sridhar and Gopalan ( 2002 ), but with the
modification in fixing the rating scales at a lower
range based on the maximum and minimum dam-
age by A. catalaunalis (Balaji 2006 ; Table 4 ). As
the damage on reproductive parts such as flowers
and capsules influence yield more than the leaf
damage, lesser flower and capsule damage and
more leaf damage were equated to a particular
score (Table 5 ).
Based on per cent damage on leaves, flowers,
and capsules for an accession, individual scoring
was given and subsequently were summed up to
calculate the cumulative score and accordingly
the scoring grade (1–9) was allotted by referring
the grade chart and resistance rating was made.
In the first field evaluation, based on leaf and/
or flower damage, only few accessions were
rated highly resistant or resistant or moderately
resistant. Whereas several accessions were ei-Table 1 Reports from Tamil Nadu on resistance in sesame against A. catalaunalis
Name of tolerant/resistant varieties/cultivars/accessions Reference
ES 22, Si 250, ES 12 Mahadevan 1988
SI-53, SI-75, SI-810, SI-882, SI-935, SI-968, SI-970, SI-1002, SI-1004,
SI-1029, SI-1671, SI-3315/6, SI-3315/11, PDK-31, PDK-20-3-1, PDK-59-1
Mahadevan et al. 1989ES 22, SI-250, TMV 3, S. alatum Muralibaskaran and Mahadevan 1989
SI-250, ES 22, PDK 31, SI-810, B 67, C 1036 Thangavelu et al. 1989
ES 22, SI 250 Muralibaskaran et al. 1990
SVPR-1 Jebaraj et al. 1993
ES 22, SI-250, S. alatum Muralibaskaran et al. 1994
CO-1, TMV-3 Selvanarayanan and Baskaran 1996a
IVTS 2001-20, IVTS 2001-23, IVTS 2001-24, IVTS 2001-25, IVTS
2001-24
Vijai Anandh 2003