Weed interference factors that affect the growth of an atlantic forest tree species

Abstract

The objective of this study was to assess the possible existence of allelopathy and competition for water and nutrients of the grass Urochloa brizantha (Hochst. ex A. Rich.) Stapf cv. Marandu grown together with Schinus terebinthifolius Raddi in a greenhouse. The experimental design was completely randomized in a factorial scheme with 3 factors and the following levels: (1) one individual of the forest species with and without the presence of U. brizantha at a density of 4 individuals per pot; (2) supply of nutrients in limiting or non-limiting dose; and (3) supply of a limiting or non-limiting amount of water. We measured the height and root collar diameter of the tree seedlings, as well as the shoot and root dry weights of both species. There was competition by the grass with the tree species. The coexistence reduced the height by 30.5 cm, the root collar diameter by 1.58 mm and the shoot and root dry weights by 22.7 g and 9.5 g, respectively, of S. terebinthifolius. The greater supply of water in the pots increased the height by 18.9 cm of the S. terebinthifolius seedlings compared to the plants grown with limited water supply. Evidence was also observed of competition for nutrients, principally at the largest nutrient addition level, where the presence of the grass caused an additional decrease in the root collar diameter and shoot dry weight of the tree species, while the shoot and root dry weights of the grass increased. The results did not allow evaluating the existence of allelopathy of U. brizantha on S. terebinthifolius.

INFLUENCE OF Urochloa brizantha ON THE GROWTH AND NUTRITIONAL ABSORPTION OF TREE SPECIES

“…In studies with native tree species, Monquero et al (2015) evaluated the effect of increased densities of U. decumbens on the growth of Senegalia polyphylla, Enterolobium contortisiliquum, Ceiba speciosa and Luehea divaricata and found that the presence of the competing species negatively affected the growth of these tree species even at the lowest density of two plants per pot. Santos et al (2019b) observed that the coexistence with U. brizantha negatively affected the growth of Schinus terenbtifolius. All species of these studies are considered to be pioneers or early secondary (CARVALHO, 2003;LORENZI, 2014), which usually have higher growth potential than late secondary and climax ones, hence having lower growth in the presence of U. brizantha, different from Cordia trichotoma, which virtually did not show responses of growth, because it is early to late secondary, naturally having slow growth in the early stages of development.…”

Soil microbial communities, soil nutrition, and seedling growth of a Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) plantation in response to three weed control methods

“…Weeds in tree plantations reduce the leaching of nutrients, improve microclimates, reduce the risks of wind damage and water erosion, and improve biodiversity. However, it is important to strike a balance between protection of soil and water properties and reduction of weed competition with trees, because these interactions restrict the growth of tree seedlings and may cause their death (Zimdahl et al, 2007;Cierjacks et al, 2016;Peachey et al, 2017; dos Santos et al, 2019). Weeds interfere with tree growth by competing for nutrients, water, space, light, and oxygen, and may harbor pests and pathogens.…”

In vitro activity of Schinus terebinthifolius extract and fractions against Sporothrix brasiliensis

“…This species is largely found on the Brazilian coast and is distributed from the northeast to the southern parts of the country. (13) S. terebinthifolius is included on RENISUS (Brazilian National List of Medicinal Plants of Interest to the United Health System). (14) Folk medicine is used to treat ulcers, respiratory prob-lems, wounds, rheumatism, gout tumours, diarrhoea, inflammatory events, skin diseases, and arthritis.…”