Adriano Mitio Inagaki

Produção e resistência ao pendoamento de alfaces tipo lisa cultivadas sob diferentes ambientes

This work was developed during the period of February to April, 2011, with the objective of indicating which environment, greenhouse or open field, provides better conditions for production, and greater resistance to bolting of different cultivars of loose-leaf lettuce, for the climatic conditions of Caceres, Mato Grosso, Brazil, Twenty treatments were evaluated, using a randomized block experimental design in a 5 x 4 factorial of five environmental conditions (shading screens of 30 and 50%, heat-reflective screens of 30 and 50%, and open field) and four cultivars of loose-leaf lettuce (Elisa, Elizabeth, Regiane and Regina), with four replications. Harvesting was carried out 30 days after transplanting. The most productive lettuce cultivars were Regiane, which obtained the greatest number of leaves, and Regina with the smallest stem length. The environmental conditions that increased resistance to bolting in the lettuce were the shading and 50% heat-reflective screens. The cultivars themselves showed no significant differences for resistance to bolting.This work was developed during the period of February to April, 2011, with the objective of indicating which environment, greenhouse or open field, provides better conditions for production, and greater resistance to bolting of different cultivars of loose-leaf lettuce, for the climatic conditions of Caceres, Mato Grosso, Brazil, Twenty treatments were evaluated, using a randomized block experimental design in a 5 x 4 factorial of five environmental conditions (shading screens of 30 and 50%, heat-reflective screens of 30 and 50%, and open field) and four cultivars of loose-leaf lettuce (Elisa, Elizabeth, Regiane and Regina), with four replications. Harvesting was carried out 30 days after transplanting. The most productive lettuce cultivars were Regiane, which obtained the greatest number of leaves, and Regina with the smallest stem length. The environmental conditions that increased resistance to bolting in the lettuce were the shading and 50% heat-reflective screens. The cultivars themselves showed no significant differences for resistance to bolting.

Physiological responses of Urochloa ruziziensis inoculated with Azospirillum brasilense to severe drought and rehydration conditions

This study evaluated the tolerance of U. ruziziensis under severe water stress conditions and its recovery when rehydrated, based in responses of relative leaf water content and gas exchange of the crop. The experiment was conducted in green house in Oxisol. The experimental design was a randomized block design, totaling five treatments, was represented by inoculation of A. brasilense strains AbV5 + AbV6, as follow: seed inoculation, foliar spray application, seed inoculation + foliar spray application, a non-inoculated control with water deficit treatment and a irrigated control without inoculation. Drought was imposed 45 days after sowing, after the vessel was irrigated until saturation of the substrate, by total removal of irrigation for six days, and evaluated three days after the resumption of water, evaluating gravimetric soil moisture, relative leaf water content and gas exchange. Soil moisture showed non variation to treatments non irrigated, but the relative leaf water content was lower in the control without water. The control and the treatment inoculated with A. brasilense in seeds exhibited lower rates of gas exchange. Recovery full of photosynthetic activity occurred three days after rehydration in all treatments. A. brasilense foliar sprayed is efficient to increase the tolerance of U. ruziziensis to water deficit and presented higher photosynthetic rates even under conditions of severe water deficit.

Synergistic action of Azospirillum brasilense combined with thiamethoxam on the physiological quality of maize seedlings

Plant growth promoting substances, either from biological or chemical origin, are widely used in modern agriculture. In this context, this study evaluated the physiological quality of maize seed treated with thiamethoxam and inoculated with Azospirillum brasilense . Initially, we tested bacterial growth on medium with increasing concentrations of thiamethoxam. We also evaluated the physiological quality of seeds through morphometric measurements, emergence speed index and chlorophyll content by SPAD through a 2x3 factorial arrangement with seed inoculation with A. brasilense (100 mL per 25 kg of seed) and three doses of thiamethoxam (0, 80 and 120 ml per 60,000 seeds). Bacterial population showed a linear reduction according to increasing doses of thiamethoxam. The dose of 120 ml thiamethoxam (42 mg active ingredient) caused a decrease in several variables, while, the inoculation proved a positive activity in seedlings physiological quality. Thus, the inoculation combined with 80 ml thiamethoxam (28 mg active ingredient) show synergistic action in early development in maize seedlings. Keywords: Thiamethoxam, inoculant, plant growth promoting bacteria African Journal of Biotechnology , Vol 13(49) 4501-4507

Phosphorus and potassium fertilization in culture of soybean plants in the Oxisol

It is recommended to use phosphorus and potassium fertilization on soybean; however it has been common to verify the absence of effect on crop productivity, especially in no-tillage system. Thus, the study aimed to evaluate the effect of doses of superphosphate and potassium chloride in the leaf tissue nutrient content and yield of soybean growing in Oxisol. The experiment was installed in October 2011 in a randomized block design in split-bands with two factors (4x4), with four replications, totaling 64 plots, being Factor 1 with doses of superphosphate (0, 136, 331 and 700 kg ha-1) at sowing and Factor 2 with doses of potassium chloride (0, 160, 320 and 800 kg ha-1) released with cultivar Vmax RR (SYN 7059RR). In the experiment, the variables evaluated were Ca, Mg, K, P, S, Cu, Zn, Mn and Fe in leaf tissue and grain yield. The fertilization with superphosphate and potassium chloride do not interfere in leaf nutrient content and yield of soybean cultivar Vmax RR (SYN 7059RR) grown on an Oxisol of clayey with levels of P and K classified as high. In these cases, it is advisable to keep only the maintenance fertilization according to the values ​​of P and K exported by grain. Key words: Chemical fertilizer, tillage systems, organic mineral fertilizer, superphosphate, potassium chloride.