ABSTRACT
This experiment was carried out to study the effect of silver-nanopriming on germination percentage, seedling growth and mitotic cell division. The results showed that silver nanoparticles (AgNPs) significantly increased the germination percentage. Mean comparison showed that the highest germination percentages (98, 92, 96 %) were observed in the pretreated wheat (Beni Sweif 1 and Gemmieza 9) and barley (Giza 130) seeds. The results clearly revealed that shoot length, fresh and dry weights were slightly promoted by AgNPs while in roots corresponding parameters were reduced compared with those of control. Photosynthetic pigments and chlorophyll fluorescence were affected to some extent by AgNPs priming. Cytological changes in root tips of 72h and 120h germinated seeds were observed by disturbed chromosomes at metaphase and anaphase. The main types of chromosomal aberrations are: chromosomes aneuploidy, binucleate cells, deletion chromosomes, deform nuclei, micronuclei, chromosomes fragment, and stickiness chromosomes. It was found that the mitotic index significantly increased in the three pretreated tested plants compared to the control. This study infers that AgNPs could penetrate plant system and might impair stages of cell division causing chromosomal aberrations.
ABSTRACT
This experiment was carried out to study the effect of silver-nanopriming on germination percentage, seedling growth and mitotic cell division. The results showed that silver nanoparticles (AgNPs) significantly increased the germination percentage. Mean comparison showed that the highest germination percentages (98, 92, 96 %) were observed in the pretreated wheat (Beni Sweif 1 and Gemmieza 9) and barley (Giza 130) seeds. The results clearly revealed that shoot length, fresh and dry weights were slightly promoted by AgNPs while in roots corresponding parameters were reduced compared with those of control. Photosynthetic pigments and chlorophyll fluorescence were affected to some extent by AgNPs priming. Cytological changes in root tips of 72h and 120h germinated seeds were observed by disturbed chromosomes at metaphase and anaphase. The main types of chromosomal aberrations are: chromosomes aneuploidy, binucleate cells, deletion chromosomes, deform nuclei, micronuclei, chromosomes fragment, and stickiness chromosomes. It was found that the mitotic index significantly increased in the three pretreated tested plants compared to the control. This study infers that AgNPs could penetrate plant system and might impair stages of cell division causing chromosomal aberrations.