The objective of this study is to identify and quantify the floristic composition of the weed community in the rice crop waterlogged in the municipality of Arari-MA. The botanical material was obtained in three areas ...The objective of this study is to identify and quantify the floristic composition of the weed community in the rice crop waterlogged in the municipality of Arari-MA. The botanical material was obtained in three areas by randomly a hollow rectangle of 0.50 m × 0.30 m by forty five times in each plot. The aerial parts of weeds were harvested, identified, counted and oven dried with forced air ventilation at 333.15 K to 343.15 K. These data were used to determine the phytosociological parameters and the Shannon-Wiener diversity index was also calculated. A total of 6607 plants were collected, being 4115 (62.28%) in the vegetative phase and 2492 (37.72%) in the reproductive phase. The monocotyledonous group obtained the largest number of plants, 2882 in the vegetative phase and 1535 in the reproductive phase. The Cyperaceae family recorded nine species and four genera and the Poaceae, seven and four species in the vegetative and reproductive phases, respectively. The species of higher IVI in the vegetative phase was E. sellowiana in the area A1 with 82.86%, and in the reproductive F. dichotoma with IVI of 90.49% in the area A3. The individuals density and species richness were higher in the vegetative phase of the culture and the monocotyledonous group predominated with the Cyperaceae and Poaceae families, and the weed diversity among the areas was low.展开更多
The objective of this work was to verify the responses in agronomic and physiological characters of lettuce seedlings when submitted to different doses of humic acids and the presence or absence of inoculation of the ...The objective of this work was to verify the responses in agronomic and physiological characters of lettuce seedlings when submitted to different doses of humic acids and the presence or absence of inoculation of the bacterium Azospirillum brasilense. The experiment was carried out at the Protected Cultivation Station and Biological Control Teacher Mário César Lopes, belonging to the Experimental Stations Nucleus of the State University of the West of Paraná. The experimental design was a randomized block design, in a 5 × 2 factorial scheme, with four repetitions, totaling 40 plots. The first factor consisted of five solutions containing humic acid (100%, 75%, 50%, 25% and 0%) and the second factor was the presence or absence of the diazotrophic bacterium Azospirillum brasilense obtained by commercial product. Germination tests were carried out in addition to the determination of agronomic characters such as the number of fully expanded leaves, plant height, stem diameter, main root length, shoot dry mass, root dry mass, total dry mass, and Dickson quality index. The association of diazotrophic bacteria and humic acids did not influence the emergency rate, mean emergence time, mean speed of emergency, emergence speed index, plant height, and root length of lettuce seedlings. The dilutions of humic acids, regardless of inoculation with bacteria diazotrophic favored the development of the number of leaves, stem diameter and Dickson quality index. Inoculation of lettuce seeds with diazotrophic bacteria associated with the addition of humic acids, favored the development of the dry mass of root and total dry matter.展开更多
文摘The objective of this study is to identify and quantify the floristic composition of the weed community in the rice crop waterlogged in the municipality of Arari-MA. The botanical material was obtained in three areas by randomly a hollow rectangle of 0.50 m × 0.30 m by forty five times in each plot. The aerial parts of weeds were harvested, identified, counted and oven dried with forced air ventilation at 333.15 K to 343.15 K. These data were used to determine the phytosociological parameters and the Shannon-Wiener diversity index was also calculated. A total of 6607 plants were collected, being 4115 (62.28%) in the vegetative phase and 2492 (37.72%) in the reproductive phase. The monocotyledonous group obtained the largest number of plants, 2882 in the vegetative phase and 1535 in the reproductive phase. The Cyperaceae family recorded nine species and four genera and the Poaceae, seven and four species in the vegetative and reproductive phases, respectively. The species of higher IVI in the vegetative phase was E. sellowiana in the area A1 with 82.86%, and in the reproductive F. dichotoma with IVI of 90.49% in the area A3. The individuals density and species richness were higher in the vegetative phase of the culture and the monocotyledonous group predominated with the Cyperaceae and Poaceae families, and the weed diversity among the areas was low.
基金Coordination for the Improvement of Higher Education Personnel(CAPES)by the scholarship of the master’s degree and resources for conducting the research.
文摘The objective of this work was to verify the responses in agronomic and physiological characters of lettuce seedlings when submitted to different doses of humic acids and the presence or absence of inoculation of the bacterium Azospirillum brasilense. The experiment was carried out at the Protected Cultivation Station and Biological Control Teacher Mário César Lopes, belonging to the Experimental Stations Nucleus of the State University of the West of Paraná. The experimental design was a randomized block design, in a 5 × 2 factorial scheme, with four repetitions, totaling 40 plots. The first factor consisted of five solutions containing humic acid (100%, 75%, 50%, 25% and 0%) and the second factor was the presence or absence of the diazotrophic bacterium Azospirillum brasilense obtained by commercial product. Germination tests were carried out in addition to the determination of agronomic characters such as the number of fully expanded leaves, plant height, stem diameter, main root length, shoot dry mass, root dry mass, total dry mass, and Dickson quality index. The association of diazotrophic bacteria and humic acids did not influence the emergency rate, mean emergence time, mean speed of emergency, emergence speed index, plant height, and root length of lettuce seedlings. The dilutions of humic acids, regardless of inoculation with bacteria diazotrophic favored the development of the number of leaves, stem diameter and Dickson quality index. Inoculation of lettuce seeds with diazotrophic bacteria associated with the addition of humic acids, favored the development of the dry mass of root and total dry matter.
