ABSTRACT

The seeds of three varieties of eggplant - Ngwa large (Solanum gilo), Ngwa 2 (Solanum gild) and Gawuta (Solanum molongena) were exposed to X-irradiation at different X-ay dosages in milligray (1 MGy, 2 MGy, 4 MGy, 6 MGy and 8 MGy) to determine the effective dose for the three varieties by subjecting the data collected to linear regression on the basis of their plant height after 2 weeks of germination. The effective doses for Ngwa large were 4MGy and 5 MGy, for Ngwa2 3 MGy and 8 MGy and Gawuta 2MGy and 3MGy which were planted with all their control. X-irradiation had a positive effect on the height of the plant and induced early flowering especially at higher level of xray irradiation except for Gawuta (S. melomgena L). For Ngwa 2, plants exposed at 8 MGy had the highest performance followed by 3 MGy and control.For Ngwa large, plants exposed at 5 MGy performed better than that of 4 MGy followed by control at the first 7 weeks of data collection. From the 8 th week to the last the control was the highest followed by 5 MGy and 4 MGy. For Gawuta the performance was not distinctive. There were five primers used and three of the primers gave polymorphism, there were 13 polymorphic alleles in all the three primers. Ngwa large 5 MGY had four alleles with 1200 bp, 1000 bp, 950 bp and 500 bp are present on it and absent on the other two samples Plate 1, Table 1. Ngwa2 control had one allele with 300 bp and the allele is absent on the other two samples, Ngwa-2 3 MGY and Ngwa-2 8 MGY had another allele with 850 bp absent on the control sample Plate 3.Gawuta control had three alleles with 600 bp, 500 bp and 300 bp that are absent on the two treatment samples, Gawuta 3 MGY also had three allele at position 650 bp 450 and 350 that are absent on the other samples Plate 3. A dendrogram was constructed to determine phylogenetic relationship existing among the varieties under study. The scale of the dendrogram constructed from the RAPD data was between 0 and 0.4 with the mean value of 0.2. At a truncated line of 6% (a distance of 0.06) 2 clusters [NL5 (Ngwa large 5 MGy), GW2 (Gawuta 2 MGy), GW3 (Gawuta 3 MGy), N2C (Ngwa 2 control) N23 (Ngwa 2 3 MGy) and N28 (Ngwa 2 8 MGy)] and N2C (Ngwa 2 control), GWC (Gawuta control) and NL4 (Ngwa large 4MGy) are distinguishable from the dendrogram. The occurrence of S. gilo and S. melongena together in all the clusters is an indication of close relatedness and possibility of having a common ancestor (monophyletic).