Reserve carbohydrate levels in the boles and structural roots of five multipurpose tree species in a seasonally dry tropical climate

• Published in: Forest ecology and management Vol. 146; no. 1; pp. 145 - 158
• Main Authors: Latt, C.R, Nair, P.K.R, Kang, B.T
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2001; Elsevier
• Subjects: Agricultural and farming systems; Agroforestry trees; Agronomy. Soil science and plant productions; Biological and medical sciences; Dactyladenia barteri; Fundamental and applied biological sciences. Psychology; General agroecology. Agricultural and farming systems. Agricultural development. Rural area planning. Landscaping; General agronomy. Plant production; Generalities. Agricultural and farming systems. Agricultural development; Gliricidia sepium; Leucaena leucocephala; Non-structural carbohydrates; Pterocarpus soyauxii; Senna siamea; Soluble sugar; Starch; Nigeria; West Africa; Africa; Starch; Non-structural carbohydrates; Agroforestry trees; Soluble sugar; Fodder tree; Root; Interspecific comparison; Alfisols; Gliricidia sepium; Storage carbohydrate; Leucaena leucocephala; Multipurpose tree; Tropical climate; Chrysobalanaceae; Leguminosae; Sandy clay loam soil; Seasonal variation; Dicotyledones; Angiospermae; Spermatophyta; Biological accumulation; Agroforestry; Metabolic storage
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/S0378-1127(00)00456-4

It is important to know the seasonal cycles of reserve carbohydrates in agroforestry trees because their ability to sprout after cutting may depend on reserve carbohydrate levels. Such information is lacking for tropical agroforestry trees. Reserve carbohydrate trends were examined in uncut, 12-year-old multipurpose trees in the seasonally dry climate of Ibadan, Nigeria. Species included Dactyladenia barteri, Gliricidia sepium, Leucaena leucocephala, Pterocarpus soyauxii, and Senna siamea. Definite seasonal trends were observed. Concentrations of sugar and total reserve carbohydrates (sugar+starch) were highest during the dry season. Starch had two maxima, one early in the dry season, and one early in the wet season. Conversion of starch to sugar seemed to occur as trees developed drought tolerance. All carbohydrate values decreased as active growth resumed during the wet season. In general, all carbohydrate values were relatively low as active growth continued; they increased only when dry weather slowed growth. In several species, carbohydrate concentrations in the lower boles decreased during reproductive growth, especially during the last phase of fruit maturation. Significant linear correlations were found between concentrations of sugar and total reserve carbohydrates and a number of weather variables — rainfall, temperature, relative humidity, and solar radiation. Correlations with starch were much lower than for sugar, although several were significant, suggesting that seasonal trends in starch are too complex to be described adequately by linear correlations.