Earliness and spineless promising mutants in safflower Carthamus tinctorius L

This investigation was carried out at experimental and research farm, Faculty of Agriculture, Zagazig University, Egypt during four winter seasons 2007/2008, 2008/2009, 2009/2010 and 2010/2011 for induction of mutations in safflower (Carthamus tinct or ius L). Two mutagens [gamma ray (y -ray) and sodium azide (NaN3)] were used in this study. The gamma ray doses were 100, 150 and 200 Gray (Gy), while the concentrations of sodium azide were 0.001, 0.002 and 0.003 m (moll) at pH 3. Three safflower lines; line 3, line 6 and Line 79 from Oil Crop Research Section, Crop Research Institute, Agricultural Research Center (ARC) were used in this study. The selected variants at the present study included apparent morphological characters, especially earliness and spineless change, as well as the change in seed yield, seed yield attribute characters and seed shape. These variants were screened to isolate 5 at M1 and 428 at M2 generations. These mutants characterized with, spineless leaf, plant height (dwarf and semi-dwarf), flowering date (earliness, lateness), seed shape and seed weight. In M3 i generation the stable mutants at line 3 (28 mutants) followed line 6 (15 mutants) and line 79 (7 mutants) have been identified. These mutants possessed spineless and earliness performance as a first target in addition high seed yield. At M4 generation the stable M4 mutant lines were screened and recorded, especially these possessed spineless and earliness. The number of promising mutants at M4 generation were 18, 9, 2 in line 3, line 6 and line 79, respectively. These results confirmed that the �-ray was more effective than Sodium - azide (chemical mutagen) as well as the line 3 genotype were more response than other two genotypes (line 6 and line 79) for induction of stable promising mutants according to [mal results at M4 .Regarding to oil content which consider as an important criterion in oil seed crops, therefore, the oil seed of promising mutant lines at M3 generation was estimated. The results confirmed that promising mutants derived line3 possess high oil content, spineless and earliness, i.e., number 4 and number 2 (Tip spine) as well as high seed yield. While most mutants at line 6 lower than the parent genotypes. In contrast, promising mutant number 2 at line 79 possess higher oil content than the parent genotypes. These results confirmed that the mutagen treatments in this cases successes in breaking of highly negative correlation between spineless leaf and highly oil content, and subsequently may be possible for development of Egyptian spineless, earliness and high oil content cultivars for cultivation at aimed desert lands as new oil crops in Egyptian agriculture.