Abstract:
Rice plant is subjected to attack by more than 100 species of insects, of
which 20 species of economic importance cause 20-30% yield losses every
year. Yellow stem borer (YSB: Scirpophaga incertulas) and leaf folder (LF:
Cnaphalocrocis medinalis) of rice are considered as prime devastators
responsible for major economic loss. Different rice genotypes (indigenous,
aromatic and hybrids) were screened out against YSB and LF during kharif,
2010, 2011 and 2012 at Rice Research Station, Chinsurah, Hooghly, West
Bengal to determine their level of resistance by recording dead heart, white
ear head for YSB and damaged / folded leaves for LF. Three-year data
indicated that rice hybrids viz. KRH 2, Arize 6444 and PHB 71 showed
lowest level of dead heart incidence; CNRH 103, CNRH 105 and Arize 6444
with lowest incidence of white head; and PHB 71, CNRH 104 and CNRH
103 with high level of resistance against LF. Among indigenous rice
genotypes, minimum dead heart incidence was recorded in Kumargore,
Seetasail and Vaidehi, whereas white head incidence was minimum in
Champakushi, Jaya Silet and Rupsail. The lowest level of LF infestation
was noticed in Vaidehi, followed by Jaya Silet and Dudheswar. Aromatic
rice genotypes viz. Tulaipanji, Pusa Basmati 1 and Badsabhog showed high
level of resistance against dead heart, whereas low white head infestation
was in Seetabhog, NC 324 and Radhunipagal. LF infestation was minimum
in Tulaipanji, Seetabhog and Radhunipagal. These resistant genotypes would
be useful for future breeding programme in achieving higher rice productivity.
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