S. Poovarodom, N. Tawinteung, P. Ketsayom
Leaf analysis has been successfully used as a guide in diagnosing nutritional problems and as a basis for fertilizer recommendations in fruit trees in many countries. However, little information is available on leaf nutrient standards for durian (Durio zibethinus Murr.) which is native to Southeast Asia. An alternative approach to the traditional methods of developing leaf nutrient standards is to survey highly productive orchards and assume that nutrient concentrations in these orchards are optimal. This technique was used to establish tentative leaf nutrient concentration standards for durian. The survey was carried out in five mature 'Mon Thong' commercial orchards and one experimental plot located in Eastern Thailand, the largest commercial durian producing area in the region. Second and third durian leaves from terminals of the first flush after harvest were sampled at one month intervals and concentrations of N, P, K, Ca, Mg, Fe, Mn, Cu and Zn were analysed during the 1998/99 and 1999/2000 growing seasons. Seasonal variations in durian leaf concentrations were similar to those of other evergreen and deciduous fruit trees. As leaves matured, concentrations of N, P and K decreased but Ca, Mg, Fe and Mn increased. The trends for both years were similar for all 6 orchards. Concentrations of all nutrients were in close agreement for both years except for those of Cu and Zn which were higher for the 1999/2000 growing season. Minimum variations in nutrient concentrations occurred between October and December for both seasons, thus leaf nutrient concentration standards are based on October to December samples. Since all 6 orchards surveyed have a history of high yield, the nutrient concentration ranges found at these sites were proposed as tentative nutrient concentration standards for durian. The proposed tentative standards are 2.0-2.4% N, 0.15-0.25% P, 1.5-2.5% K, 1.7-2.5% Ca, 0.25-0.50% Mg, 40-150 ppm Fe, 50-120 ppm Mn, 10-25 ppm Cu and 10-30 ppm Zn. The leaf nutrient standards developed for durian in this study are within the range of other tropical and deciduous fruit trees, with the exception of K which is rather high compared to some tropical fruit trees such as litchi, mango and citrus.
Poovarodom, S., Tawinteung, N. and Ketsayom, P. (2002). DEVELOPMENT OF LEAF NUTRIENT CONCENTRATION STANDARDS FOR DURIAN. Acta Hortic. 594, 399-404
DOI: 10.17660/ActaHortic.2002.594.51
cv. "Mon Thong", Durio zibethinus Murr., plant analysis, macronutrients, micronutrients, nutrition

Acta Horticulturae