Tissue Specific Nutrient Localization in the Arachis hypogaea Seedling Root

Abstract

The focus of this research was to investigate the tissue specific localization and estimation of seed-derived and exogenous nutrients in seedling roots of Arachis hypogaea. Element distribution pattern in different root tissues were studied with respect to growth, development and nutrient interaction. All cells of plant including root cells need nutrients for growth, development and maintenance. The nutrients are transported from source to sink region followed by their distribution and storage in specific tissues. The transport and distribution of nutrients depends on the availability and nutrient interactions within cell and its surrounding environment. Qualitative study and quantitative estimation of the nutrient distribution patterns in different root tissues can help us understand transport, ion homeostasis and adaptive response at cellular level thus having greater ecophysiolgical significance. Most studies have investigated transport using tracer molecules or radioactive elements; however our experimental design allowed us to directly investigate several macro-nutrients without the influence of any xenobiotic compounds. Unlike most studies, our method allowed us to estimate concentrations of elements in whole root as well as in specific tissues thus further dissecting the plant ionome studies precisely to tissue or cellular specificity. Significant outcome of the research includes the identification of the role of cell type, tissue type, developmental stage and nutrient interaction in element distribution. The study also indicated the existence of a layer of P and S rich pericycle cells that may function as a “symplasmic boundary” and may have significant role in ion regulation.