Sunflower chlorophyll levels after magnetic nanoparticle supply

Abstract

This study reported the results of an experimental investigation regarding the chlorophyll contents in sunflower seedlings supplied with low concentrations of magnetic nanoparticles. Iron and iron-cobalt oxides were prepared in the form of colloidal nanoparticles for the administration in the culture medium of young plant seedlings during their very early ontogenetic stages - as possible basis of new biotechnological tool in plant growth controlling. The changes in the contents of chlorophyll A, chlorophyll B and carotene like pigments were evidenced by spectral measurements. Magnetite nanoparticles influenced negatively the photosynthetic pigment biosynthesis by diminishing chlorophyll content with up to 50% while slighter effect was evidenced in the case of cobalt ferrite nanoparticles that induced only up to 28% chlorophyll level decreasing. The influence upon photosynthetic system LHC II was revealed as consistent with the higher diminution of chlorophyll ratio in the case of cobalt ferrite supplied seedlings than for magnetite supplied ones sustaining the hypothesis of photosynthesis sensitivity to the presence of magnetic nanoparticles stress.   Key words: Sunflower seedlings, photosynthetic pigments, nanosized metal oxides.