كليدواژه :
اسپرس , موتاسيون , اتيل متان سولفونات , دز بهينه , Mutation , Sainfoin , ethyl methane sulfonate , optimum dosage
چكيده لاتين :
Investigation of mutagen damages, control of treatment conditions, selection of desirable dosages and estimation of mutation frequency are the main requirements in a mutation breeding program. The objective of this study was to assess the effect of various ethyl methane sulfonate (EMS) dosages including 0.0, 0.2, 0.4, 0.6, 0.8, 1 and 1.2 percents for 12 hrs on germination response and seedling vigor under laboratory, greenhouse and field conditions. One, two and four open-pollinated populations of sainfoin were used in the laboratory, greenhouse and field, respectively. The increase of EMS dosages decreased germination, rootlet and shootlet lengths and emergence. Unpeeled seed compared with peeled seed decreased damages, but pretreatment did not significantly affect seedling characters. EMS dosage x seed coat was highly significant. The results showed that LD50 was 0.8 in peeled seed and 0.6 in unpeeled seed treated with EMS for 12 hrs. The results also revealed that percentage of plant survival and pollen fertility decreased significantly with increasing dosage in all populations. ʹKhansarʹ and ʹShahrekordʹ populations were sensitive to the EMS as compared with ʹOrumiehʹ and ʹKaraj2ʹ populations. EMS treatment caused considerable variation in plant height, number of stems in plant and number of inflorescence, but crude protein, crude fiber and single plant yield were not affected. Morphological variation and deviations from the control population were observed in plants of MI and M2 generation.
