Growth, Development and Seed Production of Goosegrass1

Abstract

-E. indica is one of the most problematic weeds in the world because it is present in almost every continent, and there are reports of multiple resistance to herbicides by some biotypes. The objective of this paper was to analyze the growth, the development and the production of this plant's seeds, in order to generate information about its biology that can be useful for management. The experiment was carried out in a greenhouse from May to September 2015. Sixteen samples were taken during the development cycle of the plant: 3, 10, 17, 24, 31, 38, 45, 52, 59, 66, 73, 80, 87, 94, 101 and 108 days after emergence (DAE). The response variables were based on a leaf area and dry matter of each one of the parts of the plant and the number of seeds produced per plant. At 12 DAE, 80% of the seedlings of E. indica had emerged, and each plant produced more than 120 thousand seeds, closing their cycle at 120 DAE. Between 38 and 43 DAE, the plant had fast emission of new tillers, exponential accumulation of the total dry matter and substantial increase of the absolute growth rate. Due to the data observed here, we concluded that the management of E. indica must be done preferably before 38 DAE due to the exponential growth after this period, preventing the plant from producing seeds and spreading to other places. planta: 3, 10, 17, 24, 31, 38, 45, 52, 59, 66, 73, 80, 87, 94, 101 Keywords: Eleusine indica, relative growth, biomass allocation, weed biology. RESUMO -E. indica é uma das plantas daninhas mais problemáticas do mundo por estar presente em quase todos os continentes, e há relatos da resistência múltipla a herbicidas que alguns biótipos apresentam. O objetivo deste trabalho foi analisar o crescimento, o desenvolvimento e a produção

Chemical Control of Glyphosate-Resistant Goosegrass

“…Its intrinsic characteristics, such as photosynthetic C4, rapid growth and high seed production, which can germinate under a large range of soil conditions in terms of salinity, pH, compaction and temperature, make this species extremely competitive (Ismail et al, 2002;Chauhan and Johnson, 2008;Takano et al, 2016a). Goosegrass thrives mainly on roadsides and machinery tracks, due to the compaction of the soil in these places and the absence of other plants around it (Arrieta et al, 2009).…”

“…As for this species, the time between emergence and the beginning of tillering is only nine days, which means a short time to perform the application at the appropriate stage (Takano et al, 2016a). There is an interesting hypothesis to explain the lower efficacy of herbicides on goosegrass in advanced stages.…”

Goosegrass Resistant to Glyphosate in Brazil

“…It presents a fast growth, autogamy, C4 cycle and high seed production (over 120,000 plant -1), which are spread by the wind (Kissmann and Groth, 1997;Mueller et al, 2011;Takano et al, 2016. ).…”

“…One of the goosegrass characteristics is its rapid tillering capacity, as the stadium of 2-3 tillers and 5-6 tillers can be reached at nine and twenty-four days after its emergence (DAE) respectively (Takano et al, 2016). The rapid growth of this species suggests that, for operational reasons, applications in the field cannot always be carried out in suitable stadium for its control.…”

Sistemas de manejo de plantas daninhas utilizando o novo herbicida pyroxasulfone visando ao controle químico de gramíneas em soja

“…Em solos de baixa fertilidade ou compactados apresenta vantagem sobre muitas outras espécies, sobressaindo seu poder de competição (Kissmann e Groth, 1997). Cada planta é capaz de produzir mais de 120 mil sementes (Takano et al, 2016).…”