Vegetative growth of two mulberry species (Morus multicaulis and M. alba) under greenhouse and field conditions
Morus alba and Morus multicaulis, common ornamental species in Chile, were studied regarding their growth and dry matter production. In Santiago (Metropolitan Region), plants from vegetative propagation, one part growing under field conditions and the other in a plastic greenhouse were used; both with similar soil, water availability and cutting system (0.20 and 0.40 m). Periodically, four shoots per selected plant were measured for length, number of leaves and dry weight. Previously, a correlation between dry matter and foliar size (length, width, area) of each species was established to estimate the latter. Correlation coefficients obtained had a R2 higher than 0.60 whereas the length and width used to estimate foliar area had an R2 of 0.96 to M. multicaulis and 0.95 to M. alba when correlated to the real area measured. The growth curve for total weight was superior for M. multicaulis at the beginning, but at the end was greatest for M. alba. In the greenhouse there were more leaves per shoot in M. alba, and there were no differences between species in the field. The shoot length changed with environmental conditions, as it was better with M. alba in the greenhouse and with M. multicaulis in the field. It was concluded that M. alba is more sensitive to the temperature regimes used in this study.