THESIS

132
For the interspecific crossing among S. melongena and other three species (S.
americanum, S. villosum and S. nigrum, S. villosum is more closely related to S.
melonegena than S. americanum and S. nigrum. This due to the crosses between S.
melongena and those three species gave hybrid plants but when confirmed the
hybridity by pollen fertility, ploidy levels and morphological characters, they were not
the true hybrid. In contrast, when used S. melongena as male parent, the hybrid fruits
were obtained but no viable seeds from the cross between S. melongena and S.
villosum.
Moreover, from the interspecific hybridization among S. torvum and the three
species (S. americanum, S. villosum and S. nigrum), S. villosum is more closely
related to S. torvum than S. americanum and S. nigrum when considered the
percentages of fruit setting and number of seeds per fruit. S. villosum has the higest
percentages of fruit setting and number of seeds per fruit when compare to S.
americanum and S. nigrum (Table 17).
Furthermore, from the interspecific hybridization among S. americanum, S.
villosum and S. nigrum, we found that S. americanum is more closely related to S.
villosum than S. nigrum when considered the percentages of fruit setting and number
of seeds per fruit (Table 18).
Therefore, germplasm characterization provides essential, valuable
information for breeding programs. Knowledge on genetic diversity and relationships
among the S. melongena germplasm may play significant role in breeding programs to
improve fruit quality and resistance to biotic and abiotic stresses of S. melongena.
Interspecific hybridization is possible between Solanum spp. This may accelerate
diversity and increase gene pool for breeding programs. Diversity within germplasm
is critical for S. melongena breeding programs. However, all F1 hybrids from
interspecific hybridization are sterile which may be overcome by using hormone
and/or some chemical such as GA (gibberlleic acid) and colchicines for doubling the
set of chromosome.