Sudhida Gautam ¹, R. Maruthadurai ¹, R. D. Gautam ¹

Affiliations
1 Biological Control Laboratory, Division of Entomology, Indian Agricultural Research Institute, New Delhi-110012, IN

Abstract

A semi-synthetic diet named as the power packed green lacewing feed (PPGF), comprising whey protein, soybean granules, proteinex powder and glucon mixed in equal quantity by weight, was developed for Mallada desjardinsi (Navas) for increasing its reproductive potential. The cost of 1000g PPGF was worked out to be Rs. 621.00 (approx. US $14). It had a shelf life of four months at 5-10°C. The females of M. desjardinsi survived for 49 days when fed on the diet stored for eight weeks, on par with the control (58 days). Thereafter, survival declined to the lowest (16.8 days) when fed with the diet stored for 15 weeks. The predator laid maximum eggs (811.2/female) on the diet stored for four weeks, on par with that on diet stored up to eight weeks (774 eggs/female) and the control (888 eggs/female). The fecundity declined to the lowest (220.6 eggs) on PPGF stored for 15 weeks. Per cent hatchability was on par for up to eight weeks and declined significantly, with 33% on the diet stored for 15 weeks. In PPGF+honey (20%) feed combination, another peak of egg laying was recorded in females after 4^th week, whereas egg laying ceased in females that were fed with only 20% honey after the 4^th week. The females survived for up to 9 weeks maintaining productive age of more than eight weeks. PPGF+honey (20%) offered to the adults of M. astur also enhanced the fecundity (668.0) as against the control (292.14). Besides, other biological attributes were not affected due to the feeding on PPGF. These studies suggest a great potential for commercialization of PPGF in order to promote cheaper production and field utilization of green lacewings.

Keywords

PPGF, Multiplication, Mallada desjardinsi, M. astur, Shelf Life.

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R. Bhoopathi ¹, Sudhida Gautam ¹, R. D. Gautam ¹, Subhash Chander ¹

Affiliations
1 Biological Control Laboratory, Division of Entomology, Indian Agricultural Research Institute, New Delhi 110 012, IN

Abstract

Life tables were constructed under Delhi conditions for Zygogramma bicolorata in order to determine the key mortality factor acting on the species. The pupal stage was found to be the key mortality stage that contributed most to the overall mortality followed by egg stage. Pupal malformation, failure to lay eggs and infertility were prominent mortality factors. The main cause of mortality of older larvae was their inability to burrow into hard and dry soil for pupation. Besides, weather factors in general were found to have an effect on all developmental stages of Z. bicolorata. The sex ratio was biased towards females with their proportion being 0.6-0.7. The generation trend index was very high (272.21) during July followed by October (231.07) and August (199.40). The generation mortality was low during June-October while it was high during January, May and December.

Keywords

Life Table, Zygogramma Bicolorata, Parthenium hysterophorus.

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