EFFECT OF SALICYLIC ACID AND VARIETIES ON INCIDENCE OF APHID AND YIELD OF MUSTARD

Abstract

The experiment was conducted in the experimental field of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka during the period from November, 2014 to March, 2015 to find out effect of salicylic acid and varieties on incidence of aphid and yield of mustard. The experiment comprised of two factors; Factors A: Levels of salicylic acid (3 levels)- S0: 0 mM SA (control), S1: 0.2 mM SA,S2: 0.4 mM SA and Factor B: Mustard varieties (5 levels)- V1: BARI Sarisha-1, V2: BARI Sarisha-13, V3: BARI Sarisha-14,V4: BARI Sarisha-15 and V5: BARI Sarisha-16. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. For salicylic acid, at early flowering stage, the lowest number of aphid (2.87) was observed from S2 and the highest number (3.12) from S0. At mid flowering stage, the lowest number of aphid (3.17) was observed from S2 and the highest number (3.52) from S0. At late flowering stage, the lowest number of aphid (3.52) was observed from S2 and the highest number (3.93) from S0. At flowering stage, the lowest infested plant (5.27%) was found from S2, while the highest (7.87%) from S0. The highest seed yield (1.85 t/ha) was recorded from S2, whereas the lowest (1.44 t/ha) from S0. Due to different mustard varieties at early flowering stage, the lowest number of aphid (2.67) was recorded from V5, whereas the highest number (3.34) from V1. At mid flowering stage, the lowest number of aphid (3.06) was recorded from V5, whereas the highest number (3.52) from V1. At late flowering stage, the lowest number of aphid (3.46) was recorded from V5, whereas the highest number (4.00) from V1. At flowering stage, the lowest infested plant (4.91%) was recorded from V5, whereas the highest (8.49%) from V1. In case of interaction effect, at early flowering stage the lowest number of aphid (2.27) was observed from the treatment combination of S2V5 and the highest number (3.67) from S0V1. At mid flowering stage, the lowest number of aphid (2.70) was observed from the treatment combination of S2V5 and the highest number (3.77) from S0V1. At late flowering stage, the lowest number of aphid (3.00) was observed from the treatment combination of S2V5 and the highest number (4.47) from S0V1. At flowering stage, the lowest infested plant (2.71%) was recorded from the treatment combination of S2V5, while the highest (10.14) from S0V1. The highest seed yield (2.46 t/ha) was found from the treatment combination of S2V5, while the lowest (1.04 t/ha) from S0V1. It was revealed that 0.4 mM SA and BARI Sarisha-16 was superior for controlling mustard aphid and also for obtaining higher yield and yield contributing characters of mustard.