Growth of Tree Species in Coexistence with Palisade Grass Urochloa brizantha (Hochst. ex A. Rich.) Stapf CV. Marandu

• Published in: Advances in Weed Science 2019-01, Vol.37
• Main Authors: SANTOS, T.A., RESENDE, A.S., SILVA, F.F., MORAES, L.F.D., CHAER, G.M.
• Format: Article
• Language: English
• Subjects: Cedrela fissilis; Coexistence; Diameters; Dry matter; Environmental restoration; Evaluation; Experiments; Grasses; Guazuma ulmifolia; Hymenaea courbaril; Interference; Mortality; Native species; PLANT SCIENCES; Rainforests; Reforestation; Sapindus saponaria; Schinus terebinthifolius; Species; Studies; Trees; Urochloa brizantha; weed competition
• ISSN: 0100-8358; 1806-9681; 1806-9681; 2675-9462
• DOI: 10.1590/s0100-83582019370100113

The effect of palisade grass (Urochloa brizantha) was evaluated on the growth of five tree species from the Atlantic Forest biome in Seropédica, RJ, Brasil. This study consisted of five experiments in a completely randomized design. The effect of grass on the growth of Cedrela fissilis, Guazuma ulmifolia, Schinus terebinthifolius, Sapindus saponaria, and Hymenaea courbaril was tested in pots at each experiment. Height, collar diameter, and plant mortality were measured monthly. Shoot and root dry matter of tree species and grass were evaluated at 180 days. A strong interference of palisade grass was observed on the growth of the five studied species. The reduction of growth in height and collar diameter reached 32 and 29% in S. saponaria and 26 and 44% in G. ulmifolia, respectively. Grass interference was even higher on dry matter accumulation, promoting reductions in the shoot that ranged from 48% in H. courbaril to 90% in G. ulmifolia and S. terebinthifolius. Root dry matter of tree species was reduced between 28 and 84% in relation to the control without the presence of grass. The species C. fissilis had a mortality rate of 83% in coexistence with U. brizantha. The other species, except S. saponaria, presented mortality from 15 to 30% under competition. This study evidences the importance of controlling grasses in reforestation projects aiming higher gains in growth and survival of tree species. RESUMO: Avaliou-se neste trabalho o efeito da presença do capim-braquiarão (Urochloa brizantha) sobre o crescimento de cinco espécies arbóreas do bioma Mata Atlântica, em Seropédica-RJ. O estudo abrangeu cinco experimentos em delineamento inteiramente casualizado. Em cada experimento, testou-se em vasos o efeito da gramínea sobre o crescimento das espécies Cedrela fissilis, Guazuma ulmifolia, Schinus terebinthifolius, Sapindus saponaria e Hymenaea courbaril. Foram medidos mensalmente a altura, o diâmetro do coleto e a mortalidade das plantas. Aos 180 dias, avaliou-se também a massa seca de parte aérea e radicular das espécies arbóreas e da gramínea. Houve forte interferência do capim-braquiarão sobre o crescimento das cinco espécies estudadas. A redução de crescimento em altura e diâmetro do coleto chegou, respectivamente, a 32% e 29% em S. saponaria e a 26% e 44% em G. ulmifolia. A interferência da gramínea foi ainda maior sobre o acúmulo de massa seca, promovendo reduções na parte aérea que variaram de 48% em H. courbaril a 90% em G. ulmifolia e em S. terebint