The effects of diazotrophic bacteria inoculation associated to phosphate fertilization on plant growth and leaf gas exchange parameters in maize plants (Zea mays L.) were investigated in the present study. Maize plants were grown in 13-L pots filled with clayey Rhodic Hapludox in a greenhouse. Treatments were arranged in a randomized block design in a 4 × 2 factorial: four seed inoculation treatments [control (non-inoculated); inoculation with Azospirillum brasilense strain AbV5; inoculation with Herbaspirillum seropedicae strain SmR1; and inoculation with two bacteria strains (A. brasiliense + H. seropedicae)] and two phosphate fertilization levels [no fertilized or fertilized with phosphorus (300 mg dm-3 of P 2 O 5)]. Phosphorus fertilization resulted in higher plant height, stem diameter, number of leaves per plant, leaf area, dry matter yield of leaves, stems and sheaths of maize plants, regardless of seed inoculation with diazotrophic bacteria. Seed inoculation with A. brasilense and H. seropedicae increased in 42% of the volume root, in 52% of the root dry matter and 25% of the plant height of maize, indicating an increase in the phosphorus solubilization or higher phosphorus use provided by the maize root system. Seed inoculation with A. brasilense associated to phosphorus fertilization increased in 23% of the relative chlorophyll content, resulting in higher metabolic structure to the photosynthetic activity of maize plants. The leaf CO 2 assimilation rate was not affected by the phosphorus fertilization and maize seed inoculation with A. brasilense and H. seropedicae.

), glyphosate + metsulfuron-methyl (720 + 2,4 g ha -1 ), além de uma testemunha sem aplicação. Avaliou-se a porcentagem de fitointoxicação, altura de planta, produtividade de raízes e o teor de fécula da mandioca. Os herbicidas aplicados isolados e em mistura não causaram sintomas de fitointoxicação nas plantas de mandioca após a aplicação. Os herbicidas aplicados isolados e em mistura não reduziram a altura de planta, produtividade de raízes e o teor de fécula da mandioca em relação à testemunha sem aplicação. Conclui-se que a aplicação isolada dos herbicidas residuais e da mistura com glyphosate apresentaram-se seletivos, quando aplicados após a poda das plantas de mandioca 'Fécula Branca'. Palavras-chaves: Manihot esculenta L. Crantz, mistura em tanque, planta daninha Abstract -Cassava varieties (Manihot esculenta L. Crantz) intended for industrial starch manufacturers are usually pruned during the period of physiological rest of the plants, requiring the adoption of management practices to prevent weed competition in the second cycle of crop development. The objective was to evaluate the selectivity of pre-emergent herbicides applied 1 Recebido para publicação em 15/01

The objective of this work was to evaluate the effects of control action (natural ripening, without ripeners) and of glyphosate, paraquat, fluazi-p-butil, ethephon, etyl-trinexapac, sulfometuron methyl and KNO 3 on the number of stalks per area, diameter of the median third of stalks and productivity (tons of canesstalks per hectare), and brix, pol of the sugarcane and extractable sugar. It was used a randomized block design with four replicates in a sub-split plots. KNO 3 contributes to improve agronomic quality by increasing productivity of stalks and the most favorable harvest period to the variable was from 60 to 120 days after ripener application (DAA). Etyl-trinexapac, sulfometuron methyl and KNO 3 increased technological variables and the most adequate harvest period for ratoon sugar cane was 120 days after application (DAA) of ripeners and control, because they provided gains for variables ATR, Brix and PC in comparison to the respective initial reference times.

No abstract

Proper handling of the wheat crop is crucial to obtain the full expression of the genotype potential. Among the various management techniques, the spatial distribution of plants and the disposal of the same plant in agriculture deserve attention. It is known that the distribution may alter the productivity; however, it is uncertain, the technological changes it might entails. With this in view, the aim of this study was to evaluate in two wheat cultivars, characteristics of agronomic interest and the technological quality of flour depending on the spacing. The experimental design was a randomized block with four replications in a factorial 4 × 2. The first factor refers to the spacing: 20, 28, 36 and 40 cm and the second factor refers to the cultivars:CD 150 and BRS Tarumã. The experiment was carried out in Santa Tereza do Oeste, western region of Parana state, in May 2011. The yield and grain moisture were reduced with increased spacing of 3.98 and 26.18%. The hectolitre weight, thousand grain weight, the moisture of the flour, ash content dry basis, the falling number, and flour color were not affected by increasing spacing. Cultivar CD 150 presented lighter color, higher weight hectolitre, lower ash content and fewer drop from the BRS Tarumã.