Micronutrient Enhancement and Localization in Rice Grains under Influence of Plant Growth Promoting Rhizobacteria

Abstract

One of the major problems faced by the world today is micronutrient malnutrition, particularly in developing countries. Because majority of the population residing in these countries cannot afford supplements, biofortification of staple crops with essential micronutrients can be a viable solution. Therefore, the present investigation was carried out to evaluate the potential of plant growth-promoting rhizobacteria (PGPR) for increasing the deposition of zinc and iron in the edible portion of rice (Oryza sativa L.) grains, i.e., endosperm. Application of PGPR increased iron and zinc content in the plants, as demonstrated by the increase in catalase and carbonic anhydrase activity. Different bacterial isolates showed differential zinc and iron uptake potential. All the bacterial isolates caused an increase in the grain zinc and iron content, whereas only some of the isolates, viz., B 15, BN 17, B 17, and B 19, primarily showed endosperm deposits of zinc and iron. Hence, we concluded that PGPR can help in increasing the micronutrient content of the host plants either directly or indirectly and their judicious application holds immense potential that can be explored to develop a sustainable strategy for biofortification of cereal grains.