000			02618nab a2200253 i 4500
003			BR-BrBNA
005			20230926090253.0
008			230808b2020 bl.ar|pooa||| 00| 0 eng |
040			_aBR-BrBNA _beng
072			_aH60 _b0336
100			_aDaramola, O.S.
245			_aTiming of weed management and yield penalty due to delayed weed management in soybean
500			_aPublicação on-line; 22 ref.; 5 tables; 1 illus.; Summary (En)
520			_a ABSTRACT Background: Weed interference is a major limiting factor for economically viable soybean production. Appropriate timing of weed management would enable farmers to make more efficient use of resources for weed management. Objective: The objective of this study was to determine the critical period for weed competition and appropriate timing of weed management for optimum yield of soybean. Methods: The treatments consisted of periods of weed infestation and weed removal for the first 14, 28, 42 and 56 days after sowing (DAS), and till harvest in a randomized complete block design with three replications in 2016 and 2017. Results: Soybean yields in both years ranged from 914-945 kg ha-1 with no weed control to 1,984-2,127 kg ha-1 in the weed-free plots; a yield loss of 53-56%. Weed infestation for the first 14 DAS had no detrimental effect on growth and yield of soybean provided the weeds were subsequently removed. Increasing period of weed interference from 14 to 42 DAS resulted in a steady decline in growth and yield of soybean. Yield losses equivalent of 32-37 kg ha-1 resulted for each day that weed control was delayed between 14 and 42 DAS. Subsequent weed control after 42 DAS did not improve growth and yield significantly, nor obviate yield depression of the crop compared to crop weed-infested till harvest. Conclusions: Results indicated that the critical period of weed competition in soybean was between 14 and 42 DAS. Hence soybean should be maintained weed-free during this period to avoid high yield loss. Keywords: critical period Glycine max (L.) Merrill manual weeding weed control weed infestation
650			_aGLYCINE MAX
650			_aSOJA
650			_aERVA DANINHA
650			_aCAPINA
650			_aÉPOCA DE CORTE
773	0		_0886 _91817 _dLondrina-PR : Sociedade Brasileira da Ciência das Plantas Daninhas, 1978 _o2023-031024 _tPlanta Daninha (Brazil) _x0100-8358; 1806-9681 (on-line) _gv. 38 p. 1-7; (2020) _wBR2023000847
856			_uhttps://www.scielo.br/j/pd/a/8Zyt9LLpQ5DZGLcDXgkSPwg/?format=pdf&lang=en
942			_cAnalítica
999			_c9761 _d9761