Chemical Control of Morning Glory Species in Sugarcane Harvested in the Dry and Semi-Wet Seasons1

Abstract

-The control of morning glory (Ipomoea spp. and Merremia aegyptia) was evaluated in five commercial sugarcane-production fields receiving applications of the herbicides sulfentrazone (0.9 kg ha . quamoclit, and I. triloba. The herbicides imazapic and mesotrione alone resulted in lower levels of control of M. aegyptia. Imazapic and the combination of mesotrione + (diuron + hexazinone) caused greater visible phytotoxicity to sugarcane than other herbicides applied during the dry and semi-wet seasons. However, the greatest loss of production was attributed to amicarbazone.Keywords: herbicide, Ipomoea spp., Merremia aegyptia, pre-emergence, post-emergence, Saccharum spp. RESUMO -Cinco experimentos foram instalados em áreas de produção comercial de cana-de-açúcar para estudar o controle de corda-de-viola (

Differential susceptibility of morning glory (Ipomoea and Merremia) species to residual herbicides and the effect of drought periods on efficacy

“…cissoides>I. triloba, whereas for amicarbazone, the order was I. quamoclit>I. triloba>M. cissoides (Campos et al, 2009). The herbicides imazapic (sprayed pre-emergence in the dry and semi-wet seasons) and mesotrione alone (applied post-emergence in the wet season) in sugarcane culture resulted in a lower control percentage of M. aegyptia but excellent control of I. hederifolia, I. nil, I. quamoclit and I. triloba (Correia, 2016).…”

“…These plants are native to South America and reproduce by seeds with approximately 50 to 300 diaspores per plant, of which only a small percentage germinate quickly while the others germinate randomly over time (Kissmann and Groth, 1999). These plants are problematic due to their climbing growth habit and twining stems and vines, which wrap themselves around crop culms and establish themselves at the apex of plants, which negatively affects photosynthetic efficiency and impedes mechanized harvesting by clogging the harvester (Correia;Durigan, 2004;Christoffoleti et al, 2006). The intensity of the losses caused by weeds varies according to which species are in the crop production area.…”

“…Over time, increased infestation by species of climbing plants, such Ipomoea and Merremia, has been observed in areas of sugarcane cultivation, and it is possible that the maintenance of sugarcane straw on the soil surface creates an environment that is more favorable for seed germination and the development of such plants due to the lower daily temperature range, greater conservation of soil moisture and soil chemical and physical improvement. Furthermore, mechanized harvesting of sugarcane facilitates the spread of morning glory seeds, either in the same area or from one area to another (Correia, 2016). A phytosociological survey of infested communities in 28 sugarcane agroecosystems indicated the presence of different morning glory species (I. nil, I. quamoclit, I. hederifolia, I. triloba, I. purpurea, and M. cissoides), and in 17 areas, the species were present in sufficient quantities to be considered important (Kuva et al, 2007).…”

Response of Three Chloris elata Populations to Herbicides Sprayed in Pre- and Post-Emergence

“…Chlorimuron has a suppressive effect of grasses when sprayed in pre-emergence (Sharma et al, 2014), and it is mainly used to control eudicot species in post-emergence. The inclusion of these non-specific herbicides to control grasses is justified by their importance in agricultural crops, either in the pre-sowing management ("desiccation") of soybean (flumioxazin and chlorimuron), maize and cotton (flumioxazin) in no-tillage systems, or in sugarcane (metribuzin and sulfentrazone), soybean (sulfentrazone) crops or for potato and tomato (metribuzin) (Corrigan et al, 2000;Jaremtchuk et al, 2008;Cahoon et al, 2014;Perez-Moreno et al, 2014;Dittmar et al, 2015;Correia, 2016).…”