Chapter 17 Bacillus thuringiensis Biological
Insecticide and Biotechnology T. R. Shieh
Downloaded by PEPPERDINE UNIV on September 25, 2017 | http://pubs.acs.org Publication Date: January 7, 1988 | doi: 10.1021/bk-1988-0362.ch017
Sandoz Crop Protection Corporation, P.O. Box 220, Wasco, CA 93280
Bacillus thuringiensis, commonly known as BT, is a gram-positive flagellated rod shaped microorganism. It is an aerobic sporeforming bacilli characterized by the formation of para-sporal protein crystals in the course of sporulation. These crystals consist of a protoxin containing active fragments, known as delta-endotoxin that are toxic to the larvae of a number of Lepidopterous species (1,2) as well as Dipterous (3,4) and Coleopterous species (5,6) of economic importance. Since the first discovery of Bacillus sotto in 1901 (7) and isolation of variety Berliner in 1911 (8), varieties of BT strains have been isolated from nature (Table I). They are classified based on serotype of flagellar antigens. They differ in their immunological and in the insecticidal properties of the para-sporal crystals produced. These BT strains of various serotypes typically harbor complex and variable arrays of extra chromosomal DNA or plasmids (9). Some strains contain more than 10 plasmids in a single subspecies. Plasmids of a larger MW has been shown to be associated with the coding of protein crystal formation in B. thuringiensis strains (10,11). It has been more than 20 years, since B. thuringiensis var. thuringiensis Berliner was first used as a microbial insecticide for control of agricultural pests. However, i t is only recently, that the world wide usage of BT products has increased substantially for pest control in agriculture, forestry and public health sectors as well. This increased usage of BT products around the world is due to the following reasons. 1. BT is active only to target insects and does not effect non-target species, wildlife or humans and i t is biodegradable and environmentally safe. 2. More recently, a number of new strains of BT are being discovered to control not only Lepidoptera spp. but also other family of pests such as mosquitoes, blackflies of public health importance. Control of a beetle belonging to Coleoptera species also becomes possible with a new BT strain. 3. BT products are effective against pests that have developed resistance to many chemical insecticides. over 20
0097-6156/88/0362-0207$06.00/0 © 1988 American Chemical Society
Phillips et al.; The Impact of Chemistry on Biotechnology ACS Symposium Series; American Chemical Society: Washington, DC, 1988.
Phillips et al.; The Impact of Chemistry on Biotechnology ACS Symposium Series; American Chemical Society: Washington, DC, 1988.
3A
3A3B
4A4B
ALESTI
KURSTAKI
SOTTO
SOURCE:
Reproduced with permission from Ref. 9.
23 JAPONENSIS
8
1
4
3
9
TOLWORTHI
22 SHANDONG I ENS IS
2
0
0
1
2
8A8C
OSTRINIAE
21
TENEBRIONIS
-
3
8A8B
COLMERI
6
0
8A8B
MORRISONι
WUHANENSIS
13
5
4 3
4
3
7
AlZAWA
19
6
ENTOMOCIDUS
20
2
1
1 YUNANENSIS
18
2
0
1
1
6 TOCHIGIENSIS
KUMAMOTOENSIS
6
4
0
1
1
5A5C
SUBTOXICUS
1
17
TOHOKUENSIS
CANADIENSΙs
1
16
GALLERIAE
1
15
INDIANA
5
2
DAKOTA
8
6
2
1
2
ISRAELENSIS
0
0
4
14
PARKISTANI
1 3
0
0
1
1
4
13
THOMPSONI
14
8
3
3
2
1
12
5A5B
3
11A11C
4A4C
5
11A11B
TOUMANOFFI KYUSHUENSIS
11
7
3
KENYAE
DENDROLIMUS
1
2
FINITIMUS
2
10
6
DARMSTADIENSIS
3
11
2
1
THURINGIENSIS
2
fShi
MW X 1Qa D
NO.
_ SEROTYPE
SUB-SPP
TOTAL
SEROTYPE
MW X 10£ D
THURINGIENSIS SUB SPP.
0
