Population Dynamics of Insect Pests and Management of Aphid, Lipaphis erysimi (Kalt.) in Mustard
Agriculture University, Jodhpur
The investigation on “Population Dynamics of Insect Pests and Management of Aphid, Lipaphis erysimi (Kalt.) in Mustard” under semi-arid condition was carried out in Rabi, 2021-22 at Research Farm of Agricultural Research Station, Mandor, Jodhpur. The aphid infestation was initiated from 51st SMW and the peak activity (126.20 aphid/10 cm terminal shoot) on 4th SMW. After that progressive decline was observed. The painted bug infestation was observed two times, where it was initiated early on 45th SMW and no infestation during from 2nd SMW to 7th SMW. Its infestation was occurred again at 8th SMW and reached to peak level (5.13 bugs/plant) at 10th SMW. The flea beetle infestation was initiated from 1st SMW and continued till 8th SMW. Peak activity on 4th SMW (0.93 beetles/plant) and then gradually declined. The leaf webber infestation was initiated from 48th SMW and reached to peak activity (2.87 larvae/plant) on 6th SMW. Natural enemy i.e., Coccinella septempunctata appeared in 1st SMW and peak activity was noticed on 8th SMW. Mustard aphid, flea beetle and leaf webber were significantly negative correlated with minimum temp. While, ladybird beetle was significantly positive with minimum temp. and sunshine, also. Painted bug and ladybird beetle both were significantly positive with maximum temp. and average temperature whereas, aphid had significantly negative with average temperature. Morning RH correlated significant positive with aphid. While, significant negative relation of ladybird beetle with morning and avg. RH. Painted bug was significant negative correlation with evening RH and avg. temperature. There was no significant relation with rainfall. Ten genotypes/varieties of Indian mustard (Brassica juncea) were screened against mustard aphid, the results revealed that TM 108-1, Kranti and Bio 902 were found as resistant, TM 267-3, TM 316, TM 304-1, RH 749, PM 31 and GDM 4 were identified as the moderately resistant while LS-FF-57 was found as tolerant.Ten genotypes/varieties of Yellow sarson (Brassica rapa) were screened against mustard aphid, the results revealed that MYS-152, YSH-401 and NRCYS 05- 02 were found as resistant, RMYS-1, RMYS-2, RMYS-3, MYS-180, MYS-183, Jhumka and Pitambari were identified as moderately resistant. Ten genotypes/varieties of five different Brassica species were screened against mustard aphid, the results revealed that none of the genotypes/varieties were found as resistant. Tapeshwari, Bhawani, Pusa Swarna, Pusa Aaditya, MBT-27, MBT-4 and GP 115-1 were identified as the moderately resistant whereas, varieties MN-1, Karantara and RTM-1351 were found as tolerant. The treatment of imidacloprid 17.8 SL was found most effective followed by thiamethoxam 25 WG and dimethoate 30 EC while, treatments of diafenthiuron 50 WP and chlorpyriphos 20 EC as least effective. The maximum yield of 3861 kg/ha was recorded in the plot treated with imidacloprid 17.8 SL followed by thiamethoxam 25 WG (3444 kg/ha) and dimethoate 30 EC (3194 kg/ha). Maximum net profit of Rs. 2,00,290 ha-1 was obtained from imidacloprid 17.8 SL. The highest B: C ratio of computed in imidacloprid 17.8 SL (6.38:1) followed by 5.60:1 in thiamethoxam 25 WG and 4.99:1 in dimethoate 30 EC while, minimum (2.71:1) was obtained in chlorpyriphos 20 EC.
PRATIHAR AKSHAY KUMAR SINGH 2022. APopulation Dynamics of Insect Pests and Management of Aphid, Lipaphis erysimi (Kalt.) in Mustard. M.Sc. thesis, College of Agriculture, Agriculture University, Jodhpur.