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In a field trial, thirteen potato cultivars were evaluated for the incidence of aphids, Myzus persicae (Sulzer) and Aphis gossypii Glover (Aphididae: Hemiptera) during rabi seasons from 2015-2016 to 2017-2018 at District Seed Farm, Department of Agriculture, Burdwan, West Bengal. Results revealed that initiation of aphid population was noticed in the crop field on or before 51st meteorological standard week (3rd week of December) with the peak at 7th MSW (3rd week of February). However, the level of aphid population was not similar in all the potato cultivars. Though the aphid population in all the cultivars decreased gradually after the peak, the attainment of a higher population differs over the duration. In general, a positive significant correlation of aphid populations was recorded with maximum, minimum temperature, and bright sunshine hours while maximum and minimum humidity had a negative correlation. Stepwise multiple regression analysis revealed that maximum temperature had a significant influence on population fluctuation of aphid. Besides, collective influence (61.8% to 76.5%) of all the abiotic factors on the aphid population was also recorded from adjusted R2 (0.618 to 0.765) in different potatocultivars.

Bio-efficacy of various treatment schedules, viz T 1 (phorate + chlorpyriphos + imidacloprid + cartap hydrochloride), T 2 (imidacloprid + acephate + chlorpyriphos + cypermethrin), T 3 (phorate + chlorpyriphos + azadirachtin + Bacillus thuringiensis var. Kurstaki), T 4 (Bacillus thuringiensis var. Kurstaki + azadirachtin ), T 5 (phorate + imidacloprid + chlorpyriphos + cypermethrin), T 6 (phorate + azadirachtin + Bacillus thuringiensis var. Kurstaki) and T 7 (control) were evaluated against Agrotis ipsilon (Hufner) and mole cricket, Gryllotalpa africana, P.de. Beau. in single potato variety, Kufi Chandramukhi during rabi season of two potato-growing years in 2013-2014 and 2014-2015 from November to February. The percentage of plant (shoot) damage was found low in T 1 (5.82 -5.87%), than by T 3 (6.12 -6.49%), T 2 (6.86 -6.92%), T 5 (7.31 -7.62%), T 6 (8.21 -8.81%), T 4 (8.61 -9.32%) and T 7 (10.70 -11.13%) respectively. Similarly percentage of tuber damage of potato was noted highest in T 7 (34.29 -43.90 %) and it was lowest in T 2 (13.15-15.66 %). Maximum marketable yield (t/ha) of potato tubers was obtained in T 2 (26.28-26.80 t/ha), which was succeeded by T 1 (26.19 -26.92 t/ha) than other treatments and it was recorded minimum in control T 7 (11.17-12.69 t/ha). Maximum cost-benefit ratio (CBR) was recorded in T 5 (1:2.03 -1:2.04) while it was found minimum in T 6 (1:1.11 -1:1.17). Among the different treatment schedules T 5 and T 2 were most effective in increasing marketable yield of potato tubers and reduction of soil pest incidence over control T 7 and also over other treatments.

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A field trial was conducted to study the impact of various potato germplasm against aphids, Myzus persicae (Sulzer) and Aphis gossypii Glover (Aphididae: Hemiptera) during rabi season from November to March in 2012-2013 and 2013-2014, respectively at Adisaptagram Block Seed Farm, Hooghly, West Bengal. The population of aphids was started on potato crop in between third week of December and first week of January irrespective of various germplasms, except K. Chipsona-2, where its infestation was initiated during second and third week of January. Then, their population was gradually increased to reach its critical level (ETL) during first and second week of January in most of the potato germplasm, except in K. Anand, K. Chipsona-1, K. Chipsona-2 and Sailaja, where it was crossed in between fourth week of January and first week of February. The peak population of aphids was observed during third and fourth week of February in most of the potato germplasm. It was observed that K. Ashoka, K. Badshah, K. Chandramukhi, K. Jawahar, K. Jyoti and K. Pukhraj were highly susceptible to the pests, while K. Anand and K. Sutlez were moderately susceptible but K. Chipsona-1 , K. Chipsona-2 and K. Sailaja were less susceptible or tolerant to the pests. Maximum tuber yield (t/ha) of potato was recorded in K. Badshah (36.58 -43.92) while it was lowest in K. Chandramukhi (22.08 -22.12).