Studies on Inducer Mediated Resistance Responses against Biological Fitness of Brevicoryne brassicae (Homoptera: Aphididae) on Brassica napus

Abstract

Cabbage aphid, Brevicoryne brassicae is among the notorious insect pests of Canola (Brassica napus) and other Brassica spp., with a reported loss of up to 75%. It has gained resistance against conventional chemical insecticides. So, to activate inducer mediated plant resistance is among the workable solutions against this pest. Henceforth, inducer-mediated resistance based on categorizes of induced-resistance (IR), nutrient-deterrence (ND) and sulphur-integration (SI), was applied in 18 treatments. Their responses against aphid development period, reproduction time, progeny production, immature becoming adults, percent survival and mortalities, were noted-down. In the IR category, all the biological parameters were affected significantly by 1 mM (1 and mM should be in the same line) mM salicylic acid-T4 treatment, whereas in ND, silicon 50 kg ha-1-T10 was more effective. Likewise, during SI studies, bio-sulphur-T15 remained an efficient one. Overall, the developmental period of B. brassicae nymphs was delayed by T10 (Si 50 kg ha-1), followed by T4 (1 mM SA), while Compost-T16 expedited their development. Besides these, reproduction time was reduced at the most by T4, followed by T15. Aphid progeny production was again decreased significantly by T4 and T10, while T16 (Compost) presented the maximum progenies. Associatively, the least number of nymphs becoming adults were shown in T4, T10 followed by T7 (1 mM CA). The highest percent nymph survival was shown in T1 (control) and T16 (compost) with the highest nymph percent mortality in T4 and T7. Hence, salicylic acid, silicon, and bio-sulphur showed maximum effective resistance responses but in concentration-dependent manner. These findings can be used in future integrated pest management programs of aphids and other specialists on related hosts. © 2021 Friends Science Publishers