Informatics Publishing Limited

V. S. Indhumathi ¹, Anusha Babu ¹, T. R. Manujula ¹

Affiliations
1 Department of Agricultural Entomology, Vanavarayar Institute of Agriculture, Pollachi (T.N.), IN

Abstract

An experiment was conducted to study the mass culture, biology and predatory potential of Australian lady bird beetle, Cryptolaemus montrouzieri on pink mealy bug, Maconellicoccus hirsutus. Predatory potential and development period of C. montrouzieri grub was studied on the adult mealybug and the duration of first, second third and fourth instar of C. montrouzieri was found to be 3.10, 4.20, 4.60 and 7.60 days, respectively when they were fed with M. hirsutus. The predator completed its grub development in 19.50 days on mealybug. The mean number of mealybug adult consumed during first, second, third and fourth grub instar of C. montrouzieri averaged to 24.20, 28.38, 44.04 and 90.52, respectively. The results revealed that this predator feeds voraciously on adult mealybug. C. montrouzieri having a remarkable predatory potential can be used to reduce population of mealybug which will result in increasing the yield of crops.

Keywords

Cryptolaemus montrouzieri, Predatory Potential, Biology, Maconellicoccus hirsutus.

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V. S. Indhumathi ¹, P. Chandramani ², J. Jayaraj ³, C. Chinniah ¹, P. P. Mahendran ¹, K. Kumutha ¹

Affiliations
1 Tamil Nadu Agricultural University, Agricultural College and Research Institute, Madurai – 625104, Tamil Nadu, IN
2 Tamil Nadu Agricultural University, Agricultural College and Research Institute, Kudumiyanmalai – 622104, Tamil Nadu, IN
3 Tamil Nadu Agricultural University, Grapes Research Station, Theni – 625526, Tamil Nadu, IN

Abstract

To evaluate the effect of four silicon fertilizers, field experiment was conducted in farmer’s holding at Poovanthi village of Sivagangai district, Tamil Nadu during 2017-2018 against sugarcane leaf hopper, Pyrilla perpusilla Walker and its parasitoid, Epiricania melanoleuca (Fletcher). Silicon fertilizers were applied @ 500 and 1000 kg ha^-1 before planting and the leaf hopper population was recorded at 150, 180, 210, 240 and 270 days after application. The results of field experiment revealed that Pyrilla population was minimum in the plots treated with calcium silicate @ 1000 kg ha^-1 (8.20 numbers/leaf) followed by calcium silicate @ 500 kg ha^-1 (8.80 numbers/leaf) as compared over untreated check (98.20 numbers/leaf) and the percent reduction over untreated check was 82.45 and 73.71 per cent, respectively. Similarly, the per cent parasitism was maximum in the treatment with calcium silicate @ 1000 kg ha^-1 (82.33%) during November, which was on par with untreated check. Hence, Pyrilla population declined to an extent of 82.45 per cent by enhancement of E. melanoleuca parasitism (82.33 %) due to the application of silicon fertilizers.

Keywords

Epiricania melanoleuca, Parasitism, Pyrilla perpusilla, Silicon Nutrition.

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