ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 56 Number 3
Effect of forms and levels of nitrogen on the growth and root starch reserves of young tea plants (Camellia sinensis L.) grown in sand culture
The effect of four forms of nitrogenous fertilizer applied at five rates to young tea plants was studied. An increase in N supply usually improved growth up to a point beyond which it was not utilized in growth. Ammonium sulphate was exceptional in reducing growth as the supply increased, and leaf symptoms presumed to be caused by ammonium toxicity were seen when this fertilizer was applied at the higher rates. The iron contents of the leaves of plant receiving ammonium sulphate or calcium nitrate as the sole source of N were much lower than those of plants receiving ammonium nitrate or urea. Root starch tended to be higher at lower rate of N. At the highest level of there was nearly complete exhaustion of root starch. Urea generally resulted in increased root starch at all levels of supply and was satisfactory as a form of for the experimental plants. The nitrogen-carbohydrate relationship and it implication on recovery of tea from pruning is discussed.