Table 1. Current status of silkworm (Bombyx mori L.) germplasm in the world*
No. |
Country |
Multivoltine |
Bivoltine |
Total |
1. |
Brazil |
10 |
65 |
75 |
2. |
Bulgaria |
- |
183 |
183 |
3. |
China |
20 |
580 |
600 |
4. |
France |
- |
53 |
53 |
5. |
India |
150 |
450 |
600 |
6. |
Iran |
- |
50 |
50 |
7. |
Italy |
- |
30 |
30 |
8. |
Japan |
30 |
1542 |
1572 |
9. |
N. Korea |
5 |
281 |
286 |
10. |
Russia |
- |
500 |
500 |
11. |
S. Korea |
6 |
300 |
306 |
12. |
Thailand |
5 |
25 |
30 |
13. |
Vietnam |
5 |
20 |
25 |
|
Total |
231 |
4079 |
4310 |
* Estimated and inclusive of probable duplicates. Source: Updated data from the CSGRC Vision 2010
Table 2. Country-wise collection of silkworm germplasm maintained in India at CSGRC, Hosur.
No. |
Country |
Bivoltine |
Multivoltine |
Total |
1. |
Bangladesh |
- |
3 |
3 |
2. |
Brazil |
2 |
- |
2 |
3. |
China |
41 |
4 |
45 |
4. |
France |
10 |
- |
10 |
5. |
India |
168 |
53 |
221 |
6. |
Iran |
3 |
- |
3 |
7. |
Japan |
39 |
3 |
42 |
8. |
Poland |
3 |
- |
3 |
9. |
Russia |
20 |
- |
20 |
10. |
South Korea |
1 |
- |
1 |
11. |
Thailand |
2 |
- |
2 |
12. |
Ukraine |
2 |
- |
2 |
13. |
Vietnam |
3 |
- |
3 |
|
Total |
294 |
63 |
357 |
Source: CSGRC Annual Report, 2001-02 updated.
Table 3. Silkworm genetic resources available in India: classification
Silkworm category |
No. of accessions |
Total |
Exotic |
138 |
|
Indigenous |
219 |
357 |
Multivoltine (MV) |
63 |
|
Bivoltine (BV) |
294 |
357 |
Geographic races |
27 |
|
Evolved races |
330 |
357 |
Breeds in current use |
48 |
|
Obsolete breed |
73 |
|
Breeding material |
141 |
|
Other collection |
95 |
357 |
Normal |
345 |
|
Sex limited race* |
12 |
357 |
* Cocoon sex limited races 2 (BV), Larval sex limited races 10 (7 BV + 3 MV)
Table 4. Indigenous and naturalised silkworm races of India
Race |
Voltinism |
Region |
Cocoon characteristics |
Barapolu |
Univoltine |
Bengal |
Greenish white, flossy cocoon, one end pointed with short filament length |
Kashmiri race (Extinct) |
Univoltine |
Kashmir |
White or yellow, elongated, oval cocoon |
Nistari |
Multivoltine |
Bengal (Introduced in 1780-1781 from China) |
Golden yellow, soft, flossy cocoon, spindle type |
Chotopolu |
Multivoltine |
Bengal |
Yellowish or creamish white, small flossy cocoon |
Pure Mysore |
Multivoltine |
Karnataka (Introduced from China in 1875) |
Creamish yellow, flossy, soft cocoon with one end pointed. |
Bulupolu (Extinct) |
Multivoltine |
Bengal |
Yellow to greenish white, flossy cocoon |
Nayapolu |
Multivoltine |
Assam |
Light yellow to white, flossy cocoon with short filament length. |
Sarupat |
Multivoltine |
Assam |
Light creamy, small, flossy, spindle shaped cocoon |
Moria white |
Multivoltine |
Assam |
Creamy white, spindle shaped, small flossy cocoon |
C. Nichi |
Originally bivoltine presently multivoltine |
Karnataka (Introduced during early 20th Century) |
White, dumb bell shaped cocoon |
HS-6 |
Multivoltine |
Karnataka |
White, dumb bell shape cocoon |
JAM races |
Bivoltine |
Kashmir |
White, oval/constricted. |
|
|
|
|
Source: K.Thangavelu (1997). Silkworm breeding in India - An overview. Indian Silk 36(2):5-13
Table 5: Silkworm breeds evolved in India
Multivoltine races evolved in India and their cocoon characteristics |
Bivoltine races evolved in India and their cocoon characteristics |
||||
Race |
Cocoon characteristics |
Race |
Cocoon characteristics |
Race |
Cocoon characteristics |
KARNATAKA |
|
KARNATAKA |
|
PAM-109 |
White, Oval |
Kolar gold |
White oval |
NB18 |
White, dumb bell |
PAM-110 |
-do- |
Mysore princess |
-do- |
NB4D2 |
-do- |
PAM-111 |
White, EFC |
Kollegal jawan |
-do- |
NB7 |
White, oval |
PAM-112 |
-do- |
TEP-2 |
-do- |
NB1C |
-do- |
PAM-113 |
White, EFC |
AW8(a) |
-do- |
CA2 |
-do- |
JAM-1 |
-do- |
C1 |
White dumb bell |
CC1 |
-do- |
JAM-2 |
White, OFC |
C5 |
-do- |
JC1 |
-do- |
JAM-21 |
White, EC |
H |
-do- |
JA2 |
White, dumb bell |
JAM-23 |
-do- |
G |
-do- |
JB2 |
-do- |
JAM-27 |
White, oval |
Hosa Mysore |
Dark yellow, oval |
PCN |
Dark greenish, |
JAM-103 |
-do- |
NS-4 |
-do- |
|
yellow, flossy, |
JAM-110 |
-do- |
MY-2 |
-do- |
|
spindle |
JAM-118 |
-do- |
P2D1 |
-do- |
CC1(SL) |
White, oval |
JAM-119 |
-do- |
RD1 |
Greenish yellow, spindle |
NB4D2 (SL) |
White, dumb bell |
JAM-122 |
-do- |
PMX |
Green yellow, elong. oval |
Mu-281 |
White, constricted |
JAM-124 |
-do- |
AP1(SL) |
Oval, light green cocoon |
Mu-285 |
White, oval |
JAM-121 |
-do- |
Mu1 |
-do- |
Mu-286 |
White, constricted |
JAM-125 |
White, EFC |
Mull |
-do- |
Mu-287 |
White oval |
SF-17 |
White, OFC |
Mu15 |
-do- |
Mu-297 |
-do- |
SS4A |
-do- |
Mu22 |
-do- |
Mu-404 |
-do- |
SS15A |
White, EFC |
Mu23 |
-do- |
Mu-488 |
White, dumb bell |
SS17 |
White,OFC |
Mu25 |
-do- |
Mu-499 |
White, slight |
AT4 |
-do- |
Mu303 |
-do- |
|
constricted |
AT9 |
White, EO |
Mu508 |
White, oval |
Mu-807 |
White, dumb bell |
IB-2 |
White, oval |
Mu509 |
Green, oval |
MG-511 |
White, oval |
IB-3 |
-do- |
Mu519 |
White, oval |
MG-512 |
White, dumb bell |
IB-9 |
White, EO |
Mu520 |
White, Dumb bell |
MG-521 |
White, oval |
TA-3 |
White, oval |
Mu953 |
|
MG-522 |
White, dumb bell |
KY-2 |
-do- |
HS2B |
|
MG-580 |
-do- |
BL |
|
TAMIL NADU |
|
Mu-716 |
White, oval |
UTTAR PRADESH |
|
|
|
Mu-718 |
White, dumb bell |
|
White, Oval |
Tamil Nadu |
|
Mu-720 |
-do- |
SF-19 |
-do- |
White |
White, spindle |
Mu-723 |
White, oval |
YS-3 |
-do- |
WEST BENGAL |
|
Mu-756 |
White, dumb bell |
YS-5 |
|
|
|
Mu-809 |
-do- |
WEST BENGAL |
White, oval |
Nismo |
White or yellow, oval |
Mu-912 |
-do- |
KA |
-do- |
Ichot |
Yellow or white, spindle |
Mu-927 |
Light yellow, dumb |
KB |
|
Itan |
Yellow, spindle |
|
bell |
|
|
A4e |
Yellow, oval |
Mu-929 |
|
MYSORE |
MU 851, 852, 853, 854 MG 405, 406, 408 and 414 (Bivoltine race) |
MBD-IV |
Golden yellow, dumb bell |
Mu-935 |
White, dumb bell |
UNIVERSITY |
|
MBD-V |
-do- |
|
-do- |
|
|
O |
-do- |
JAMMU& |
|
|
|
L |
Golden yellow, oval |
KASHMIR |
|
|
|
G |
|
SS-17 |
White, dumb bell |
|
|
D3C |
|
PLF |
-do- |
|
|
D14b |
|
KY1 |
-do- |
|
|
A18 |
Golden yellow, oval |
P5 |
-do- |
|
|
A-23 |
-do- |
PAM-101 |
White, EFC |
|
|
A-25 |
-do- |
PAM-102 |
-do- |
|
|
OS-61 |
-do- |
PAM-103 |
White, elongated |
|
|
OS-68 |
-do- |
|
oval |
|
|
OS-616 |
Golden yellow |
PAM-104 |
White, EFC |
|
|
CB-2 |
-do- |
PAM-105 |
-do- |
|
|
CB-5 |
Dumb bell |
PAM-106 |
White, Oval |
|
|
Nistari (SL) |
Golden yellow, spindle, |
PAM-107 |
White, EFC |
|
|
D14b(SL) |
oval |
PAM-108 |
-do- |
|
|
MBD-IV (SL) |
Dumb bell |
|
-do- |
|
|
Note: EC - Elongated with constriction, EFC - Elongated with faint constriction, EO - Elongated oval, OFC Oval with faint constriction
Source: K.Thangavelu, (1977). Silkworm breeding in India - An overview. Indian Silk 36(2):5-13.
Table-6: Genetic diversity range for some important heritable characters of some silkworm germplasm maintained in India
No. |
Parameters |
Min. |
Max. |
Mean |
SE |
CV% |
% over mean against |
|
Check1 |
Check2 |
|||||||
1 |
Fecundity |
|
|
|
|
|
|
|
a. |
MV Accn. |
238.00 |
518.00 |
441.1 |
7.80 |
12.99 |
-9.57 |
-2.03 |
b. |
BV Accn. |
330.00 |
528.75 |
432.4 |
3.13 |
9.34 |
+10.66 |
-4.72 |
2 |
Hatching % |
|
|
|
|
|
|
|
a. |
MV Accn. |
74.24 |
97.26 |
91.4 |
0.6 |
5.51 |
+11.38 |
-5.33 |
b. |
BV Accn. |
78.38 |
97.00 |
90.25 |
0.28 |
3.96 |
+2.0 |
+1.58 |
3 |
Ten Lar. wt.(g) |
|
|
|
|
|
|
|
a. |
MV Accn. |
19.44 |
30.39 |
25.9 |
0.3 |
9.54 |
+16.01 |
+2.22 |
b. |
BVAccn. |
19.95 |
46.60 |
35.74 |
0.27 |
9.72 |
+1.09 |
+1.57 |
4 |
Total Lar. duration (h) |
|
|
|
|
|
|
|
a. |
MV Accn. |
539.00 |
590.50 |
560 |
1.4 |
1.94 |
-14.94 |
+3.30 |
b. |
BV Accn. |
548.78 |
648.00 |
597.18 |
1.13 |
2.43 |
-8.13 |
-0.89 |
5 |
V age lar. Dur (h) |
|
|
|
|
|
|
|
a. |
MV Accn. |
133.00 |
175.75 |
151.0 |
1.2 |
5.87 |
-24.57 |
+8.64 |
b. |
BV Accn. |
138.00 |
206.00 |
164.10 |
0.92 |
7.19 |
-25.23 |
-5.73 |
6 |
Cocoon Yield/10, 000 lar. (no.) |
|
|
|
|
|
|
|
a. |
MV Accn. |
6957.00 |
9757.00 |
8482.09 |
83.77 |
7.26 |
+8.34 |
+1.05 |
b. |
BV Accn. |
5912.50 |
9291.67 |
8006.65 |
51.58 |
8.30 |
-4.18 |
-2.99 |
7 |
Cocoon Yield/10000 lar (wt.) |
|
|
|
|
|
|
|
a. |
MV Accn. |
7.37 |
13.29 |
10.69 |
0.1 |
10.97 |
+2.24 |
+11.69 |
b. |
BV Accn. |
6.84 |
17.25 |
12.64 |
0.13 |
13.48 |
-27.53 |
+5.62 |
8 |
Pupation rate (%) |
|
|
|
|
|
|
|
a. |
MV Accn. |
57.61 |
90.82 |
77.6 |
0.96 |
9.08 |
+15.75 |
+3.54 |
b. |
BV Accn. |
57.92 |
91.19 |
78.85 |
0.56 |
9.10 |
-3.74 |
-9.73 |
9 |
Single Cocoon weight (g) |
|
|
|
|
|
|
|
a. |
MV Accn. |
0.999 |
1.452 |
1.28 |
0.01 |
8.41 |
-0.62 |
+0.54 |
b. |
BV Accn. |
1.021 |
1.911 |
1.578 |
0.01 |
7.86 |
-15.33 |
+4.82 |
10 |
Single shell weight (g) |
|
|
|
|
|
|
|
a. |
MV Accn. |
0.125 |
0.237 |
0.18 |
0.00 |
13.15 |
+5.85 |
+9.04 |
b. |
BV Accn. |
0.132 |
0.361 |
0.281 |
0.04 |
12.84 |
-25.98 |
+11.03 |
11 |
Shell ratio (%) |
|
|
|
|
|
|
|
a. |
MV Accn. |
12.259 |
16.655 |
14.74 |
0.13 |
6.727 |
+6.27 |
+8.12 |
b. |
BV Accn. |
12.97 |
22.20 |
17.86 |
0.12 |
8.58 |
+9.52 |
-6.27 |
54 Multivoltine and 167 Bivoltine accessions were studied
For details - refer to catalogue on silkworm (Bombyx mori L.) Germplasm Vol.I Edt.: K.Thangavelu, et. al 1997, CSGRC, Hosur.
Table-7: Schedule of silkworm rearing for conservation
Bivoltine |
- Once in a year (Favourable season) |
Multivontine - |
- 5 times in a year |
Sl. No. |
Rearing Activities |
Multivoltine |
Bivoltine |
1 |
Release of eggs |
After cold storage |
After cold storage |
2 |
Incubation |
8 - 10 days |
10 - 12 days |
3 |
Brushing |
1 - 2 days |
1 - 2 days |
4 |
Early stages (1-3 instars) |
10 - 12 days |
12 - 14 days |
5 |
Adult stage (4-5 instars) |
10 - 12 days |
12 - 13 days |
6 |
Spinning stage |
1 - 2 days |
1 - 2 days |
7 |
Harvesting and cocoon assessment |
After 5th day of spinning |
After 6th day of spinning |
8 |
Grainage operation |
4 - 5 days |
4 - 6 days |
|
Consignment of eggs (period) |
35 days |
10 months |
|
Total period |
75 - 80 days |
350 - 370 days |