Locally, only two Arachis hyiogaea L caltivars have boon so far released for grors. Despite the unresohed contresersy on dic potentiality of mutation breeding.
induced mucagonesis has bn proven uscful ،n dcning the gcocuc pool of this quite
unpotant protein and oil crop among othcr oil crops. The main objective of this research
was to estimate the induced genetic variance and broadsassc heritability for peanut seed
ycld component traits of mutagen-treated seeds under controllod conditions. Seeds of
tio culuv ars, Giza 5, and Giza 6, vere planted at the Egyptian Atomic Energy (EAE)
Experiment Station at Anshas during June of thc three consecutive years of 2002 to 2004.
To induce physical and chcmical mutagcnesis, air-dried seeds of both cuhivars vere
treated ith both physical and ebcmicai mutagens. The physical mutagauc effect vas
induced by gamma (7) rays using Cobalt 60 rCo). Seeds c irradiated by four doses
-100, 200, 300, arid 400 Gray’ (GY). The chemical mutagcns verc of two sources: ethyl
methane sulphonatc (EMS), C, Iڑ O, S and sodium azide (SA). NaN,. Three
concentrations of 1.0. 2.0, and 3.0mM in a 0.1 M phosphate buffer of pH 3.0 ‘.cre used
for each one. Mutagcris showed variance heterogeneity only for cv. Giza 5. Both the
ithin-rnutagon phcnotypic and genetic variances, for the SA doses, were quite
heterogeneous (P <005) for all four studied seed characters - pod number plant’, seed
plant’, pod weight plant’, seed weight plant”. En general, thin each cultivar, broad-
sense heritability estimates had a range of 0.47-0.77 for (liza 5, and of 0.56-0.79 for Gira
6 based on mulagcn mean across the four characters. Mutagcnwisc, hcritabilitiy estimates
were relatively different irrespective of seed character and cultivar. Sodium nude rates
resulted in a dilTczvncc of cight percentage points from gamma ray doses (70% w. 62%)
and of three points from EMS doses (70% vs. 67%). Therefore, selection for these
specific seed characters scans effcciic under SA-treatod seed conditions. However, the
within-mutisgen hentability values c inconsistent and did not foLlow a definite pattern
for any seed yield components. In futwe research, it would be more valid to select a dose
range, instead, to recommend fer further in-dopth mutation-induood advanced research on
the molecular lcvel. This is to investigate ‘hether these mutagen induced effects
happened duc lo the occurrence of any real mutants and if they arc new Loci or allclic to
existing bd. Therefore, more appropriate screening technique(s) should be suggsicd by
breeders to identify and assay those real mutants on DNA level.
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