Correlations between plant height and light interception in grasses by different light meter devices

Abstract

This study tested if the type of light meter device can influence the relationships between plant canopy height with light interception (LI) and leaf area index (LAI), in different types of warm-season grasses. LI and LAI were measured using Digital Plant Canopy Imager model 120 (CI-120) (CID Bio-science®) and Plant Canopy Analyzer LAI-2000 (LI-COR®). Seven warm-season grasses were evaluated Urochloa decumbens (Stapf) R.D. Webster.; Urochloa ruziziensis (R.Germ. & C.M. Evrard) Crins; Megathyrsus maximum (Jacq.) B.K. Simon & S.W.L. Jacobs cv. Tanzânia, M. maximum (Jacq.) B.K. Simon & S.W.L. Jacobs cv. Mombaça, Pennisetum purpureum Schumach. cv. Mott, P. purpureum Schumach. cv. Taiwan A-146 2.37, P. purpureum Schumach. cv. Roxo. There was a predominance of non-significant correlations between canopy height with LI and LAI measured using CI-120 ( p > 0.05). Moderate to strong correlations were obtained between canopy height with LI and LAI measured using LAI-2000 (p < 0.01). LAI-2000 was found to be a potential device for modelling relationships between canopy height with LI/LAI in warm-season grasses. The findings of this trial indicate that the type of light meter device has a strong influence on the correlations between canopy height and light interception in warm-season grasses.