| Popis: |
Health, productivity, and reproductive success of plants as primary producer are dependent on soil mineral nutrients, among many other biotic and abiotic factors. Mineral nutrients have been categorized into major and minor nutrients. Both deficiency and excess of nutrient availability cause deficiency stress and nutrient toxicity, respectively; “sufficiency range” being the amount needed for optimal growth and productivity. Plants deploy a variety of developmental and adaptive mechanisms, root architecture being one, to maximize its chances of acquiring mineral nutrition in the sufficiency range. Past approaches to maximize crop yield and productivity relied on abundant application of mineral nutrition as chemical fertilizers and formed the basis of green revolution. The degradation of environment became an unintended collateral damage. The present strategy, therefore, is to unravel the molecular basis of nutrient uptake by plant roots, mobilization, assimilation within the plant, and the source–sink relationship in order to improve nutrient uptake efficiency, and nutrient utilization efficiency (NUE). Given the vastness of the subject involving developmental and adaptive traits, complicated and interconnected nature of the various factors that regulate mineral nutrition, the present endeavor is limited to providing an overview of key transporters that are involved in uptake of the sixteen soil-derived mineral nutrients. The roles of transcriptional regulators such as microRNAs are just beginning to be unraveled. Together with transporters, small RNAs and transcription factors hold the key to future crop breeding and improvement programs through improved root system architecture and nutrient uptake, mobilization, and assimilation. |
