Biotechnology of pepper
Peppers belong to the genus Capsicum. They are found around the world in various edible forms and they exhibit great variations in size, shape, flavour and colour as well as plant habits. Five main species have been domesticated. (Cfrutescens L., C. chinense Jacq. ,C. baccatum L., C. pubescens R.& P., and C.annuum L.) among which C. annuum is the most widely cultivated. Two types of cultivars can be distinguished: sweet and pungent. A horticultural classification of peppershas been made by Smith45 based on the size, shape, colour and taste (sweet or pungent) of the fruit. The transfer of characters from wild species to cultivated genotypes is hampered by interspecific incompatibility and/or hybrid sterility. Only in a few cases have these barriers been overcome through embryo culture and somatic hybridisation. A recent update on pepper in vitro regeneration and transformation has been made by Steinitz et al.,46 and a summary of genes of interest transferred into pepper is given in Table 10.2.Table 10.2 A summary of gene transfer and corresponding agricultural traits into pepper and eggplant | ||||||||
Plant species |
Transformation methods |
Gene utilised |
Agricultural traits |
Inheritance |
Field or greenhouse test |
Reference |
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Capsicum annuum |
A.t. |
CMV coat protein |
CMV resistance |
R1 |
51 |
|||
A.t. |
CMV satellite RNA |
CMV resistance |
R1 |
59 |
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A.t. |
Bar gene |
Herbicide resistance |
R1 |
60 |
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Solanum melongena |
A.t. |
CryIIIB |
Insect resistance |
R1 |
No |
71 |
||
A.t. |
Synthetic CryIIIA |
Insect resistance |
R1 |
F |
72 |
|||
A.t. |
Mutagenised CryIIIB |
Insect resistance |
R2 |
F |
75, 76 |
|||
A.t. |
Synthetic CryIAb |
Insect resistance |
Not Tested |
No |
77 |
|||
A.t. |
Cysteine protease inhibitor |
Insect resistance |
No |
70 |
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A.t. |
IaaM from Pseudomonas synringae |
Parthenocarpy |
R2 and more |
G |
79, 80 |