NUTRIENT MANAGEMENT BY EXPLOITING GENETIC DIVERSITY OF POTATO - A REVIEW

Different plant species and potato cultivars differed in nutrient use efficiency . Potassium efficiency was lowest for potato followed by wheat and sugar beet. Potato had a similar total K requirement as wheat. Wheat and sugar beet were similarly K efficient. Wheat had a lower K requirement than sugar beet but more roots, therefore, a small influx was sufficient. Sugar beet had a high K requirement and fewer roots. Maize was less Zn-efficient than potato and sunflower. The low Znuptake efficiency of maize was associated with a low Zn influx which nullified the effect of its high root-DMA ratio. Potato cv. Kufri Chandramukhi had a higher K uptake efficiency than Kufri Badshah and Kufri Jyoti. Kufri Chandramukhi maintained higher K influx by utilizing more non-exchangeable soil K than Kufri Jyoti and Kufri Badshah. However, potato cv. Kufri Chandramukhi had a lower Zn uptake efficiency than cv. Kufri Badshah due to its lower root-DMA ratio than Kufri Badshah because Zn influx was similar in both the cultivars. Kufri Chandramukhi was more P efficient than Kufri Badshah and Kufri Pukhraj. Roots of P- efficient genotypes had the capacity to keep more applied P in available form than inefficient genotypes. Comparison of DNA finger prints of these genotypes revealed the genetical variation in the genotypes, responsible for different nutrient use efficiency. Potassium efficient species and cultivars maintained higher K influx by using higher amount of less mobile soil K (non-exchangeable K) whereas phosphorus efficient cultivars had shown higher P influx due to the capability of their roots to reduce fixation of applied P in the soil. Higher root growth (root-shoot/DMA ratio) was responsible for higher zinc efficiency of potato cultivars.