30 documents found, page 1 of 3
Burial depths favor Italian ryegrass persistence in the soil seed bank
Cechin,Joanei; Schmitz,Maicon Fernando; Hencks,Jonas Rodrigo; Vargas,Andres Antonio Monge; Agostinetto,Dirceu; Vargas,LeandroABSTRACT: Italian ryegrass (Lolium multiflorum Lam.) is a weed broadly found in fields cultivated with wheat and barley crops. Seed inputs into the soil before harvesting winter crops increase seed bank, ensuring survival. This study evaluated the persistence of Italian ryegrass seeds subjected to burial depths over time. Experiments were carried out in the field for two years in randomized block experimental d...
May the crossing between diploid and tetraploid Italian ryegrass transfer glyph...
Schmitz,Maicon Fernando; Cechin,Joanei; Vargas,Andrés Antonio Monge; Henckes,Jonas Rodrigo; Vargas,Leandro; Agostinetto,DirceuABSTRACT Italian ryegrass (Lolium multiflorum Lam.) is a grass weed found in winter cereals, with several glyphosate-resistant diploid populations. Furthermore, the use of Italian ryegrass tetraploid genotypes creates an opportunity to increase the forage demand in replacement of diploid populations. The aim of this research was to evaluate the crossing capacity between glyphosate-resistant diploid and tetraplo...
Control of Italian ryegrass and Alexandergrass in corn using different corn sow...
Piasecki,Cristiano; Ovejero,Ramiro Fernando Lopez; Picoli Junior,Gilmar José; Francisco Bellini,Luiz; Agostinetto,Dirceu; Vargas,LeandroABSTRACT Glyphosate-resistant (GR) Italian ryegrass (LOLMU) and Alexandergrass (URPLA) are troublesome weeds in corn cropping systems in Southern Brazil. The emergence pattern of those weeds is not uniform and may change according to the season’s environmental characteristics. Also, herbicide resistance has been diminishing the success of the weed control programs. The objectives of this study were to evaluate ...
Oxidative stress and differential antioxidant enzyme activity in glyphosate-res...
Piasecki,Cristiano; Carvalho,Ivan Ricardo; Cechin,Joanei; Goulart,Francisco A. P; Maia,Luciano Carlos da; Agostinetto,Dirceu; Caverzan,AndréiaABSTRACT Biochemical assays in a time-course were employed to evaluate stresses induced by glyphosate treatment in resistant and sensitive biotypes of Conyza bonariensis. Two experiments were conducted assessing glyphosate doses and time-course after treatment. The doses of glyphosate ranged from 0 to 11840 g ae·ha–1 and assessments performed until 552 h after glyphosate treatment (HAT). The objectives of this ...
Germination, viability and longevity of horseweed (Conyza spp.) seeds as a func...
Agostinetto,Dirceu; Vargas,Andrés Antonio Monge; Ruchel,Queli; Silva,Jéssica Dias Gomes da; Vargas,LeandroABSTRACT: In Brazil, horseweed is one of the most important weeds because of the resistance to herbicides and high competitive for the crops. A large of losses were reported in major crops such as soybeans, wheat and corn, where the use a no-tillage system and the herbicide resistance promote better establishment. A correct understanding of the way temperature influences germination enables the prediction of th...
Properties of the enzyme acetolactate synthase in herbicide resistant canola
Durigon,Miria Rosa; Mariani,Franciele; Santos,Fernando Machado dos; Vargas,Leandro; Chavarria,GeraldoABSTRACT Mutations in the gene that encodes the enzyme acetolactate synthase (ALS), conferring plant resistance to ALS inhibitor herbicides, can reduce or inhibit enzymatic function. The objective of this work was to determine the functionality and kinetic characteristics of the enzyme ALS and evaluate the action of the herbicides imazapic (imidazolinone) and metsulfuron-methyl (sulfonylurea) on the activity of...
Yield, germination and herbicide residue in seeds of preharvest desiccated wheat
Perboni,Lais Tessari; Agostinetto,Dirceu; Vargas,Leandro; Cechin,Joanei; Zandoná,Renan Ricardo; Farias,Humberto De SouzaAbstract: The goals of this study were to evaluate herbicide application rates at different timings for preharvest desiccation of wheat (Trial 1), as well as to evaluate the effect of the timing of herbicide desiccation at preharvest and harvest timing (Trial 2) on yield, germination, and herbicide residue in wheat seed. In Trial 1, treatments consisted of two application rates of glufosinate, glyphosate, paraq...
Development stages horseweed in soybeans competition
Silva,Diecson Ruy Orsolin da; Agostinetto,Dirceu; Vargas,LeandroABSTRACT: The objective of this study was to evaluate the relative competitive ability of soybean with different development stages of hairy fleabane. Two experiments were conducted in greenhouse, in a completely randomized design. In the experiment it was tested soybean and hairy fleabane competition at different stage of development (rosette and 15 cm height) at the proportions 100:0, 75:25, 50:50, 25:75 and ...
Soybean yield loss and economic thresholds due to glyphosate resistant hairy fl...
Agostinetto,Dirceu; Silva,Diecson Ruy Orsolin da; Vargas,LeandroABSTRACT: The interference of glyphosate resistant hairy fleabane (Conyza bonariensis) has caused yield losses in soybean crop. Knowledge of the economic threshold is an important aspect for the economic management of resistant weeds. Because of it, the interference of the glyphosate resistant hairy fleabane density on the soybean yield loss was evaluated, as well as to estimate the economic threshold. Two expe...
Morphophysiogenetic characterization of wild poinsettia biotypes with low resis...
Agostinetto,Dirceu; Ulguim,André da Rosa; Vargas,Leandro; Silva,Jessica Dias Gomes da; Langaro,Ana ClaudiaAbstract: The objective of this work was to compare wild poinsettia (Euphorbia heterophylla) biotypes as to their morphological characteristics, as well as to determine their genetic similarity in the state of Rio Grande do Sul, Brazil, and to confront the light compensation point of susceptible biotypes and of biotypes with low-resistance level to glyphosate. Besides the morphology analysis, the study included...