Dec 16, 2014 - Abstract: Tropical Tasar silkworm (Antheraea mylitta Drury) is an economic insect which is source of income for the poor tribal people of central ...
JCBPS; Section D; Nov . 2014 – Jan. 2015, Vol. 5, No. 1 ; 960-963.
E- ISSN: 2249 –1929
Journal of Chemical, Biological and Physical Sciences An International Peer Review E-3 Journal of Sciences Available online atwww.jcbsc.org
Section D: Environmental Sciences CODEN ( USA): JCBPAT
Research Note
Studies on effect of antennae amputation on the fecundity and hatching performance of tropical tasar silk moths during grainage operations. Kamaraj, S.,* Tiwari, M.D., Minakshi, M., Shabnam, N.K., Madhusudhan, K.N., Serani, N., Sharma, S.P and Alok Sahay. Silkworm Seed & Rearing Technology section,Central Tasar Research and Training Institute, Piska Nagri, Ranchi-835303, Jharkhand, India. Received: 28 November 2014; Revised: 16 December 2014; Accepted: 22 December 2014
Abstract: Tropical Tasar silkworm (Antheraea mylitta Drury) is an economic insect which is source of income for the poor tribal people of central and other parts of India. The seed sector of tasar culture is suffering due to insufficient production of seeds which is becoming major constraint in the productivity enhancement. During grainage operations, even after oviposition for 72 hours, some eggs still remain inside the abdomen of female moth. In the present study, to increase the egg laying capacity of the female tasar moth, the antennae was amputated. The results revealed that, antennae amputated moths laid more number of eggs in comparison with non-antennae amputated moths. The results also confirm that, the eggs laid by antennae amputated moths showing increased hatching percentage in comparison with control ones. The outcome of the present study reveals that, the amputation of antennae of female moths can be used during grainage operations in tasar culture which helps in enhance the seed production. Keywords: Grainage, Antennae, Amputation, Fecundity, Hatching.
960 J. Chem. Bio. Phy. Sci. Sec. D, Nov. 2014 – Jan. 2015; Vol.5, No.1; 969-963.
Studies…
Kamaraj, S. et al.
INTRODUCTION Seed is the basic component in tasar culture which contributes significantly for production tasar silk in India. In tasar culture seed production is carried out by government and private sectors (NGOs) to meet the demand of tasar farmers. The requirement of seed is not all achieved by both sectors due to nonavailability of the sufficient seeds. Among total requirement of seed sector, approximately 40% seed has being supplied to the tasar farmers by government; private sectors and sometimes farmers themselves produce a required quantity of seeds. Generally in tasar grainages, coupled female moths allowed to oviposition to lay the eggs up to three days. In spite of three days oviposition, the majority of eggs remains inside the abdomen of coupled female moth. There is urgent need to develop the methodology to increase the egg laying capacity of the couple female tasar moth. In case of coupled mulberry female silk moths, amputation of antennae showed increased egg laying during grainages1 . Similarly, the present study was designed to compare the egg laying capacity of antennae ampituted tasar female moths with normal moths. The study also concentrates on the impact of amputation of antennae of female moths on the hatching percentage of the eggs laid by the moths. MATERIALS AND METHODS The antennae of ten (10) coupled female moths with three replicates were amputated and allowed for egg laying for three days alogn with the non-antennae amputated moths. After 72 hours of oviposition, the eggs laid by the both amputated and control moths were counted. The hatching percentage of eggs laid by both amputated and control moths were recorded after ten days of coupling. RESULTS The results of the present study revealed that, both during 1st crop and 2nd crop grainage operations, the antennae amputated coupled female moths laid more number of eggs (increased fecundity) of all the ten days of experiment period. During 1st crop grainage, 23.97% of improvement in eggs laying has been noticed in antennae amputated coupled female moths in comparison with the non- antennae amputated coupled female moths (Table 1). Similarly, during 2nd crop grainage also, 15.16% of improvement in egg laying was noticed in antennae amputated coupled female moths in comparison with control ones (Table 2). The increase in 6.36% and 4.96% in hatching was noticed in antennae amputated coupled female moths laid eggs in comparison with non-antennae amputated coupled female moths laid eggs in 1st crop and 2nd crop grainage respectively (Table 1 & 2). DISCUSSION The enhancement of egg laying capacity of the moth depends upon also genetic character of moth and nutritional value of host plants1 . Along with these factors, induction of stress also plays a key role in the enhancement of egg laying capacity in the silkworm. The induction of stress in the tasar silk moths (amputation of antennae) showed the more number of eggs in comparison with moths of non-amputated antennae as observed in the present study. The results also confirms that, under stress condition tasar silkworm lays more number of eggs which also showed more hatching percentage in comparison with control moths. The result also confirms that, the work carried out by Kumar et al.1 by using mulberry silkworm which also showed enhanced silkworm fecundity noticed in different races under stress condition (clipping of antennae).
961 J. Chem. Bio. Phy. Sci. Sec. D, Nov. 2014 – Jan. 2015; Vol.5, No.1; 960-963.
Studies…
Kamaraj, S. et al.
Table 1: The comparative studies on fecundity and hatching % in antennae amputated and Normal moths during 1st crop grainage.
No. of eggs laid by moths
Days
Antenna amputated
Normal
Hatching%
% Improvement
Antenna amputated
Normal
% Improvement
1
255
183
28.24
92
86
6.52
2
306
226
26.14
93
87
6.45
3
382
223
41.62
92
89
3.26
4
332
238
28.31
94
87
7.45
5
292
221
24.32
94
88
6.38
6
278
234
15.83
95
86
9.47
7
202
185
8.42
92
87
5.43
8
295
231
21.69
93
86
7.53
9
352
264
25.00
89
85
4.49
10 Total
278 2972
222 2227
20.14 239.71
90 924
84 865
6.67 63.65
Mean
297.2
222.7
23.97
92.4
86.5
6.36
Table 2: The comparative studies on fecundity and hatching % in antennae amputated and Normal moths during 2nd crop grainage. No. of eggs laid by moths
Days
Antenna amputated
Normal
Hatching%
% improvement
Antenna amputated
Normal
% improvement
1
221
210
4.97
89
86
3.37
2
288
235
18.4
91
88
3.30
3
261
259
0.7
87
86
1.15
4
273
226
17.21
92
88
4.35
5
279
231
17.2
98
89
9.18
6
222
210
5.4
93
87
6.45
7
251
193
23.1
97
89
8.25
8
261
217
16.85
97
91
6.19
9
309
233
24.59
93
90
3.23
10
250
192
23.2
95
91
4.21
Total
2615
2206
151.62
932
885
49.68
Mean
261.5
220.6
15.16
93.2
88.5
4.96
962 J. Chem. Bio. Phy. Sci. Sec. D, Nov. 2014 – Jan. 2015; Vol.5, No.1; 960-963.
Studies…
Kamaraj, S. et al.
CONCLUSION The clipping (amputation) of antennae of female silk moth showed the more number of eggs laying and increased hatching percentage when compared to non-amputated moths. The results confirm that, the induction of stress during oviposition enhances egg laying capacity of female tasar moths. REFERENCE 1.V.Kumar, R. Singh, and S.B.Dandin, Enhancing silkworm fecundity. Indian Silk.2004, 6.
Corresponding author: Kamaraj, S., Silkworm Seed & Rearing Technology section,Central Tasar Research and Training Institute, Piska Nagri, Ranchi-835303, Jharkhand, India.
963 J. Chem. Bio. Phy. Sci. Sec. D, Nov. 2014 – Jan. 2015; Vol.5, No.1; 960-963.
