Mineral composition of leaflets in relation to the chlorosis and bronzing of oil palms in West Africa

Abstract

Some disorders causing chlorosis and necrosis of the foliage of oil palms from three West African estates have been investigated by spectrochemical analysis of the dry leaflets for potassium, calcium, magnesium and manganese.Statistical examination of the chemical analyses of leaflets from fronds of different ages, and from different positions along the frond, shows that it is important to sample and analyse separately at least upper, middle and lower fronds from each tree. Little is gained by analysing separately samples from different positions along the length of the frond.The ‘bronzing’ diseases are tentatively ascribed to deficiency of potassium. One palm is probably a case of combined magnesium and potassium deficiency. One disease, ‘lemon frond’, cannot be attributed to a deficiency of any of the elements determined.The differences in mineral composition of the leaflets between palms from the three estates are greater than those due to the diseases and a further survey is proposed to determine the range of variation of composition of healthy trees and the levels below which deficiencies set in.