Efeito do período diurno e noturno sobre o crescimento do Capim-Marandu

Abstract

This work was developed to answer the following questions: 1) Do plants grow both in the daytime and in the night? 2) Do plants grow more during day or night time? For this, the forage Urochloa brizantha cv. Marandu (marandu palisadegrass) had its growth evaluated at three times of the year: late spring, early summer and late summer. At each time, the rates of leaf elongation, stem elongation and leaf senescence were measured during the daytime and night for one week. The design was completely randomized, with repeated measures in time and eight repetitions. Leaf elongation did not vary between daytime and nighttime, nor between times of the year. The leaf senescence of marandu palisadegrass was higher in late spring than at other times of the year. The marandu palisadegrass stem elongation during the daytime was higher in late spring than in early and late summer. On the other hand, at night, stem elongation did not vary between times of the year. Stem elongation was higher during the daytime than at night only in late spring, while at other times of the year, stem elongation did not vary between daytime. In general, the growth of Urochloa brizantha cv. Marandu is similar in the day and night periods.