Analy Castilho Polizel

Compactação do solo: efeitos nas características produtivas e morfológicas dos capins Piatã e Mombaça

The grasses of the genera Brachiaria and Panicum have significant participation in the grasslands of the Cerrado region, but few studies relate their behavior in conditions of soil compaction. The objective was to evaluate the development of grasses Brachiaria brizantha v. Piata and Panicum maximum v. Mombaca in increasing levels of soil compaction. The experiment was carried out in a greenhouse at Federal University of Mato Grosso. The experimental design was completely randomized with 8 treatments and 3 replications, arranged in a factorial design involving two grasses and four compaction levels, 1.0, 1.2, 1.4 and 1.6 Mg m-3. Two cultings were made and the evaluated variables were: number of tillers NT), dry matter of leaf blade (DMLB), dry matter of stem (DMS), dry matter of root (DMR), leaf/stem ratio (DMLB/DMS); dry matter of shoot (DMSH) and the DMSH/DMR ratio. The levels of soil compaction did not influence the production of grass Piata in two growth periods. The Mombaca grass showed a reduction in production due to soil compaction in the second growth cycle.

Características produtivas e nutricionais do capim-xaraés inoculado com bactérias diazotróficas associativas

The aim of this study was to evaluate yield and nutritional characteristics of Xaraes grass inoculated with diazotrophic associative bacteria in the first cultivation in the Cerrado Oxisol. The experiment was conducted in the greenhouse. The experimental design was completely randomized factorial 6x3 consisting of: three strains of diazotrophic associative bacteria (MTAz8, MTH2 and Y2), a combination of strains MTAz8 and MTH2, nitrogen fertilization and absolute control, and three cuts (30, 60 and 90 days) in five replicates. The inoculation was performed by inserting an aliquot of 5ml of the bacterial broth containing 108 cells ml-1 in the soil near the root zone of each plant. The variables evaluated were: dry weight of shoot, crude protein, accumulation and nitrogen concentration in the shoot and determining the number of nitrogen-fixing bacteria in the soil. The fertilized soil dry matter production increased over the cuts. Among the strains Y2 showed higher accumulation of nitrogen and largest population of bacteria in the middle of the LGI culture. The nutritional characteristics of Xaraes grass declined as the cuts were made.

Green corn grown in succession to pigeon pea fertilized with phosphorus sources and lime

The practice of using green manure provides for the better utilization of chemical fertilizers and a lower cost of mineral fertilizers, and it promotes an increase in the soil’s biological activity. Green house experiment was conducted to evaluate the effect of different phosphorus sources and lime on pigeon pea growth and their effects as green manures on the dry matter production of green corn. The experiment was conducted in a greenhouse of the Federal University of Mato Grosso, Rondonopolis campus, from May 2011 to May 2012. Two sources of phosphorus (rock phosphate and triple superphosphate) were used with and without liming. The treatments were assigned in completele randomised design (CRD) with twelve replicates, the treatments (contro), rock phoshate and triple super phoshate with and without liming formed the bases of the experiment. The phosphorus was incorporated into the soil with 200 mg dm-3 of phosphorus (P2O5) based on the availability of phosphate in the sources, that is, triple superphosphate (44% P2O5) and rock phosphate Bayovar (29% P2O5) and the method of lifting the base saturation of 60%. The experiment was conducted in two phases: pigeon pea variety cv. BRS Mandarim was cultured in the first one, and the corn was variety cv. AG1051 grown in the soil under the residual effect of the first culture. Liming and rock phosphate provide a greater dry mass of pigeon pea leaves. In the presence of lime, triple superphosphate increased pigeon pea shoot and root dry weight. The cultivation of corn after pigeon pea fertilized with triple superphosphate and rock phosphate in the presence of lime, induced the dry matter production of corn. n n xa0 n n Key words: Greeno fertilization, Cajanus cajan, rock phosphate, Triple superphosphate, Cerrado Oxisol.

The inoculation of cowpea culture with rhizobial lineage in Brazilian Cerrado Region

Cowpea culture is spreading in the Brazilian Cerrado Region and specifically in Mato Grosso State. To evaluate the productive characteristics of cowpea inoculated with rhizobia lineages and grown in the Cerrado of Mato Grosso State, we conducted an experiment in a randomized block design with seven treatments, which consisted of five rhizobia lineages. Four lineages were previously isolated from cowpea (MT08, MT15, MT16 and MT23); one was a recommended lineage for cowpea in Brazil (BR3267). Two controls were included: one was equivalent to 75 kg N ha-1 nitrogen and another was without nitrogen fertilization and without inoculation of rhizobia lineage. They were arranged in six blocks totaling 42 parts of 12.5 m² each. At 40 days after sowing (d.a.s.), six plants of u200bu200beach part of floor area were collected to determine the variables plant height, dry mass of shoots and roots, total dry mass, number of nodules, dry mass of nodules, SPAD reading and relative efficiency of each lineage. Data were subjected to analysis of variance using the statistical analysis program SISVAR. To compare the means, it was evaluated with Tukey test at 5% probability and contrast analysis. Regarding the lineage used, the most satisfactory result for plant height was BR3267 lineage; however, there were statistical differences between treatments with nitrogen fertilization. There were significant differences between dry weight of shoots, total dry weight and dry weight of nodules. The BR3267 lineage presented better results in the dry mass of roots and for relative efficiency. The most satisfactory results for SPAD readings and number of nodules were observed in MT15 lineage. The BR3267 and MT15 lineages tested and analyzed had high symbiotic effectiveness for inoculation in cowpea. n n Key words: Vigna unguiculata, rhizobium, nitrogen fixation.