Cation‐exchange capacity of clonal tea roots and its implications on fertiliser responses

Abstract

AbstractFifteen genetically different tea clones showed no variation in their root cationexchange capacity (CEC) values when assessment was made separately on white (including creamy white and cream) and brown (including creamy brown and reddishbrown) portions of roots. But CEC values determined on the whole root system of the same clones were significantly different. This was true for plants varying in age from 8 to 18 months. Clones of Assam types gave lower root CEC values throughout the experimental period than China types, while clones of the Southern form of tea (Cambod) gave high root CEC values initially, which dropped rapidly as the plants became older. Root CEC of different clones was found to be negatively correlated with the brown: white root ratio and with the K: √Ca ratio of the plant tops. Ageing of plants decreased root CEC by increasing the proportion of brown roots, as a result of which the K: √Ca ratio also decreased with age.