Influence of nitrogen and potassium on root nutrient and root CEC of different tea cultivars (Camellia sinensis, C. assamica and C. assamica spp. Lasiocalyx)

An important plant management strategy is to exploit root system genetic variability of crop species or cultivars within species. Poor root growth of crop plants has been regularly observed in extremely weathered acid soils in various countries. Plant genetic variability can be defined as the heritable characters of a particular crop species or cultivar that produce variations in the growth or production between species, or cultivars of the same species, under favorable or unfavorable growth conditions. Mineral deficiency induces considerable variations in growth and morphology of roots, and such variations are strongly influenced by plant species and genotypes. Cultivar differences in root size are quite common and have been related to differences in nutrient uptake. There is extensive evidence for genotype diversity in the root characteristics of many crops in response to environment and increasing attention in using this diversity to improve agricultural production and consequently, nutrient use efficiency. Mineral deficiency induces considerable variations in nutrient acquisition and such variations are strongly influenced by plant species and genotypes as in the present study. In the light of the present findings, it appears quite logical that the effect of the passive nutrient uptake as part of the total uptake may vary with the genotype cultivated. The current findings can be taken into consideration for future manuring studies which will be helpful in coming up with species specific manuring recommendation.