Predicting nitrogen, magnesium and iron nutritional status in some perennial crops using a portable chlorophyll meter.
Shaahan M. M., El-Sayed A. A., El-Nour E. A. A. A.
Author Affiliation: Botany Department, National Research Centre, El-Tahrir St., Dokki, Cairo, Egypt.
Scientia Horticulturae 82 : 339-348
Abstract : A field study was conducted through the years 1996 and 1997 in Ismailia and Sharkia governorates, Egypt, with the horticultural crops: mangoes, mandarins, guavas and grapes. The study aimed to predict N, Mg and Fe status under field conditions using the pocket apparatus Hydro N-Tester. The data showed that the apparatus can be used as an easy and fast tool to predict both chlorophyll and N status in the leaves of fruit trees. The N-Tester readings in the range of 110-610 for mangoes, 735-820 for mandarins, 249-332 for guavas and 285-345 for grapes were considered to be in the N sufficiency range at the recommended growth stages for each crop. The N-Tester can also be used to assess Mg status for some fruit trees. Measurement of Fe status using the N-Tester chlorophyll meter under field conditions was not possible.