Pre-emergence herbicides affect seedling emergence of tropical forest tree species

• Published in: Journal of forestry research Vol. 28; no. 4; pp. 733 - 739
• Main Authors: de Souza, Diego Cerveira, Engel, Vera Lex
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-07-2017; Springer; Springer Nature B.V; Forest Science Department, Agronomic Sciences College-FCA, S(a)o Paulo State University-UNESP,P.O.Box 237, Botucatu, SP 18603-970, Brazil
• Subjects: Air pollution; Atrazine; Biomedical and Life Sciences; control;Direct; Design analysis; Diuron; Emergence; emergence;Tropical; Evaluation; Experimental design; Forestry; Forests; Greenhouse effect; Greenhouses; Herbicides; herbicides;Weed; Infestation; Life Sciences; Original Paper; Pre-emergence; Rainforests; seasonal; Seeding; seeding;Seedling; Seeds; Trees; Weed control; Weeds; Weed control; Direct seeding; Tropical seasonal forests; Pre-emergence herbicides; Seedling emergence
• ISSN: 1007-662X; 1993-0607
• DOI: 10.1007/s11676-016-0348-5

Testing techniques to reduce weed infestation is acrucial step indeveloping direct tree seeding systems. The use of pre-emergence herbicides may be an alternative to manual weeding techniques, but so far, information on howthey affectthe seeds of native tree species is scarce. We established a greenhouse experiment to evaluate the effects of four preemergence herbicides (atrazine, diuron, isoxaflutole and oxyfluorfen) on weed suppression and seedling emergence and early growth of seven tropical forest tree species (Annona coriacea Mart., Citharexylum myrianthum Cham., Cordia ecalyculata Vell., Peltophorum dubium (Spreng.) Taub.,Psidium guajava L., Pterogyne nitens Tul. and Schinus terebinthifolia Raddi). The experimental design was a randomized complete block design with five treatments and five replicates. The treatments consisted of a single dose of each pre-emergence herbicide and a control. Throughout the 60 days after sowing we evaluated weed cover and seedling emergence and early growth of tree species. Overall, our results suggest that all tested herbicides reduced weed cover;however, they also negatively affected tree species seedling emergence. Of the four herbicides tested, atrazine and diuron showed the greatest effects on tree seedling emergence,oxyfluorfen was least aggressive towards native species and isoxaflutole was most effective in weed control. Native tree species varied in their responses to herbicides, indicating that future experiments should increase the number of species tested as well as investigate how seed traits can affect the species responses to different herbicides.