Determination suitable sample method of rose apple (Syzygium jambos L.) for evaluation of plant nutrient status

Abstract

Leaf analysis is a tool for effective fertilizer recommendations in fruit trees. To achieve this goal, a suitable leaf sampling method is a very important step. This study aimed to investigate suitable leaf position and leaf age to establish standardized leaf sampling method, which can collect representative leaf sample for leaf nutrient analysis in rose apple cultivar Tubtimjan. The experiment consisted of 3 leaf positions (1st, 2nd, and 3rd leaf position) from the growing tip and 1-8 months leaf age. The results indicated that the suitable leaf position to be the index leaves were 2nd and 3rd leaf position with 6–7 months old leaf age due to minimum variation of the leaf nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) concentrations. Moreover, the concentrations of N, P, and K tended to decrease, whereas, Ca, Mg, Fe, Cu, Mn, and Zn concentrations tended to increase as leaf age increased.