Manejo da cultura de quinoa em Dois Vizinhos: adaptabilidade, dinâmica populacional de plantas daninhas e seletividade de herbicidas

Abstract

Quinoa is a species of the family Chenopodiaceae, considered as pseudocereal that can be used both in human and animal food, consisting of grains with high protein content, low cholesterol and absence of gluten. The plant tolerates saline environments and water shortages, allowing it to be cultivated in several regions. Even though it is found on supermarket shelves, quinoa is poorly understood by the population and also by technicians and farmers, who have little information about their cultivation and sanitary management. The aim of this work was to verify the best sowing season of quinoa in Dois Vizinhos-PR and weed population dynamics and herbicide selectivity for weed management. For the adaptability test, a randomized block design experiment was carried out at 15 days of May, June, July, August, September and October of 2015 to verify the best months to be indicated for sowing . At 20, 40 and 60 days after sowing, the height of the plants was measured and the number of leaves counted. The collected data were submitted to statistical analysis by the tuckey test at a level of 5% error probability. To determine the population dynamics of weeds, we used the adaptability experiment, weeding at 20, 40 and 60 days after sowing by the square inventory method, identifying the weed species and counting the number of individuals per species . Through the survey, the frequency, density, abundance, relative frequency, relative density and relative abundance and importance value index of the species were calculated. For the selectivity of herbicides to quinoa, a completely randomized experiment was carried out in greenhouse, verifying the phytotoxicity of the herbicides based on fluazifop-pbutyl, fomesafen, bentazone, atrazine, 2,4-D and paraquat + Diurom at 7, 14 and 21 days after application of the products. With the results obtained it is concluded that the best months for sowing quinoa in Two Neighbors are June, July and August. Of the weeds manifested, Bidens pilosa was the species that presented the highest infestation pressure, the species Raphanus sativus, Richardia brasiliensis, Brachiaria plantaginea and Digitaria horizontalis also presented a high index of importance value. The herbicides tested, except for fluazifop-p-butyl, caused death of the seedlings, and only fluazifop-p-butylic acid could be used to control leaf weeds in quinoa cultivation.