Varietal Preference of <i>Lipaphis erysimi</i> (Kaltenbach) on Three Species of <i>Brassica</i>
AbstractContext: Lipaphis erysimi have different type of preference to settle on different varieties of mustard. Pest preferential movement is important for ecofriendly pest control.
Objectives: The aim of this study was to determine the L. erysimi resistance varieties of mustard to get more yields by lower cost and avoid most aphid infesting varieties for higher cost
Materials and Methods: Two criteria were used to determine the varietal preference of L. erysimi, viz. (i) dispersal of aphids by cutting the base of host plants and enforce to settle on different varieties of three species of Brassica under free choice conditions, and (ii) suitability of those varieties based on the aphid infestation in the field crop condition at same season.
Results: The preferential movement of L. erysimi on ten varieties of Brassica showed significant differences (P<0.01). The variety, Bari sharisa-6 showed highest (90.00 ± 7.21) aphid settlement followed by the variety, Rai-5 (89.00 ± 5.69). The variety, Bari sharisa-10 showed lowest (10.00 ± 0.58) aphid settlement followed by the variety, Bari sharisa-11 (19.00 ± 3.61). Naturally infested aphid population on first sowing date was recorded highest (2.1 ± 0.79) on the variety Bari Sarisha-8, followed by Bari Sarisha-6 (1.93 ± 0.88). The lowest (0.19 ± 0.09) number of aphids recorded on Bari Sarisha-12. In second sowing date, Bari Sarisha-7 showed highest (19.5 ± 6.51) aphid population, followed by Bari Sarisha-8 (15.42 ± 5.72). The lowest (1.2 ± 0.38) aphid population found on the variety, Bari Sarisha-11. In third sowing date, highest (14.69 ± 5.69) number of aphids was recorded on the variety, Bari Sarisha-6, followed by the variety, Sonali-75 (14.48±4.74). Lowest number (6.06 ± 2.30) of aphids was found on the variety, Bari Sarisha-12. In the fourth sowing date, highest (15.54 ± 5.72) aphid population recorded on the variety, Bari Sarisha-8, followed by Bari Sarisha-7 (14.39 ± 5.70); and the lowest (4.41 ± 1.75) number of aphids recorded on the variety, Bari Sarisha-9.
Key words: Lipaphis erysimi; varietal preference; Brassica; Sarisha; Rai.
J. bio-sci. 17: 145-148, 2009