Growth Characteristic of Different Cultivars of Tea Plant in Response to Nitrogen Contents

Vegetative propagated plants of 6 tea cultivars were sand cultured in pots and fertilized with nutrient solution containing 0, 0.06, 0.60 and 6.00 mmol/L nitrogen. The growth characteristics of tea plants were analyzed under the four nitrogen levels. The results showed:(1)Plant height, root FW, shoot FW and SPAD value of leaves decreased significantly under nitrogen deficiency stress. Total biomass showed positive correlations with root FW and root shoot radio(P0.05).(2)The nitrogen utilization abilities were varied widely with the genotypes of tea plant. Among 6 tea cultivars, ‘Fudingdabaicha' and ‘Chungui' were identified to the genotypes with high use efficiency under the low nitrogen content.(3)The root shoot ratios were higher under nitrogen deficiency stress and the maximal variation range was 20.97% as in ‘Tieguanyin'. Root shoot ratio differed significantly by genotypes. The root shoot ratios for ‘Tieguanyin' and ‘Chungui' were 0.71 and 1.81, respectively.(4)It was demonstrated that root shoot ratio and SPAD values under nitrogen deficiency stress could be used as screening indexes for low-N tolerant tea cultivar.