Phyllochron of Paspalum notatum FL. and Coelorhachis selloana (HACK.) camus in natural pasture

Abstract

Leaf appearance rate and phyllochron are related variables which play a central role in forage production. Phyllochron is the time interval between the appearance of successive leaves and varies according to a number of environmental factors, among which temperature is the most important. The experiment was conducted in natural pasture with the aim of testing phyllochron variation under different seasons, herbage allowances, and topographic positions. Marked tillers were used to define the phyllochron, establishing a relationship between the number of leaves produced against thermal time during the sampling period. The time (expressed in °C) needed for the emergence of a leaf is equal to 1/b, where b is the slope coefficient of the regression. The lines for the season combinations, herbage allowances and topographic positions sampled were compared. Under Spring and Summer conditions, the phyllochrons for P. notatum and C. selloana were 156°C and 238°C respectively, regardless of treatment.