ABSTRACT Nitrogen (N) fertilization effectiveness in onion depends on N source, as well as on soil type and management system. The aim of the study is to investigate the effect of N sources and doses applied as top-dressing on bulb yield, leaf N contents and on the postharvest conservation of onion bulbs grown under no-tillage (NTS) and conventional tillage (CTS) systems. Three experiments were carried out: two in Lebon Régis County-SC, under NTS; and one in Caçador County-SC, under CTS. The herein tested N sources comprised urea, ammonium nitrate, calcium nitrate and ammonium sulfate, in combination to N doses applied as top-dressing (70, 140, 210, 280 and 350 kg N ha-1) in addition to the control, without N. The N sources did not affect yield parameters, leaf N content and post-harvest onion losses. The maximum technical efficiency in bulb yield was observed at N doses of 195.8 and 258.4 kg ha-1 in the no-tillage system (NTS) and at 270.7 kg N ha-1 in the CTS. The NTS enabled maximum yield at N dose 47% lower than the officially recommended one. Maximum relative commercial yield was associated with 31.1 g kg-1 of leaf N.

ABSTRACT The aim of this study was to evaluate the effect of new Ca sources sprayed on ‘Fuji Suprema’ and ‘Maxi Gala’ apple trees on nutrient levels in leaves and fruit, as well as on fruit ripening features and quality at harvest time and after cold storage. Experiments were carried out in a commercial orchard planted with ‘Fuji Suprema’ and ‘Maxi Gala’ apple trees in Caçador, Santa Catarina state, Brazil. Application of different Ca sources and untreated trees were evaluated in each experiment. Fruit were harvested at two different ripening stages and analyzed based on the following variables: fruit ripening at harvest time, as well as fruit quality and incidence of physiological disorders after 210-day storage at 1 °C. Calcium applications did not change Ca levels in the leaves and of the whole fruit. Calcium levels in fruit peel increased in cultivars Maxi Gala and Fuji Suprema due to leaf Ca applications. ‘Maxi Gala’ apples recorded higher postharvest incidence of physiological disorders, such as greater loss of fruit firmness than ‘Fuji Suprema’ apples (Due to 1-methylcyclopropene [1-MCP] application on ‘Fuji Suprema’ apples). Calcium applications did not change fruit maturation (starch index and pulp firmness) or apple pulp firmness preservation in both cultivars, although they reduced the incidence of bitter pit disorder in ‘Maxi Gala’ apples. The new sources of Ca tested did not increase Ca contents, nor did they reduced the risk for physiological disorder compared to the standard CaCl2 treatment that has been commercially used for decades as the main Ca fertilizer.

ABSTRACT The recommendations of nitrogen (N) fertilization in garlic are still based on different varieties of the current types that are infected with phytopathogenic virus. There are several methods for recommendation of nitrogen (N) fertilization in garlic, but there are no enough methods for N diagnosis in garlic obtained by meristem culture. The objective of this work was to evaluate methods for diagnosing the nutritional status of virus-free garlic subjected to N doses through the use of a specific NO3- meter in soil solution and foliar sap, portable chlorophyll meter, N content in the leaf, and its relationship with yield and quality of the bulbs. The experiments were conducted with the use of virus-free seed bulbs from the meristem culture from three sites in the 2015 growing season and two locations in the 2016 growing season in South Brazil. The treatments consisted of the application of five nitrogen doses (0, 100, 200, 300, and 400 kg ha-1) distributed in three applications during the crop cycle: 1/3 in planting, 1/3 between 30 and 40 days after planting, and 1/3 after visual bulb differentiation. The highest commercial yield was associated with doses between 269 and 307 kg ha-1 of N and the content of 26 g kg-1 of N, in the diagnostic leaf. The relative chlorophyll content was the only diagnostic technology that showed a significant correlation with commercial yield in all experimental conditions. The evaluation of the N status in the virus-free garlic crop by a portable chlorophyll meter can be a quick strategy for recommending N fertilization and ensuring high yields.

Resumen Rizobios son capaces de influir en el rendimiento de las especies no leguminosas través de la producción de sustancias fitoestimulantes. El objetivo de este estudio fue el de estudiar el efecto de la inoculación de rizobios UFRGS Lc348 y VP16 sobre la germinación y el rendimiento de millo y pasto Sudán, así como verificar si el enriquecimiento del medio de cultivo con triptófano interfiere en la interacción rizobio/planta. Para este fin se llevaron a cabo experimentos in vitro y bajo condiciones de invernadero. En el experimento con millo en condiciones in vitro, la inoculación con VP16 cultivado en medio enriquecido o no enriquecido con triptófano induce una mayor extensión de hipocótilo y epicótilo. El tratamiento UFRGS Lc348 induce una mayor extensión de hipocótilo en plantas de millo. En plantas adultas de millo no hubo efecto de la inoculación. En pasto Sudán, la inoculación de VP16 enriquecida con triptófano aumentó la masa seca de las plantas adultas. Los aumentos de elongación de plántulas de millo en condiciones in vitro pueden representar una ventaja adaptativa en la búsqueda de agua y nutrientes en el ambiente rizosférico durante el crecimiento inicial del millo. De manera similar, si se verifica en condiciones de campo, el incremento de pasto Sudán observado en condiciones de invernadero con la inoculación de VP16 enriquecido con triptófano, esto puede significar una ganancia significativa en el rendimiento del cultivo. Por lo tanto, estas relaciones entre VP16 enriquecido con triptófano y pasto Sudán deben ser verificadas en estudios posteriores en condiciones de campo.

Abstract Rhizobia are able to increase yield of non-leguminous species through production of phyto-stimulating substances. This study aimed to evaluate the inoculation effect of rhizobia UFRGS Lc348 and VP16 on millet and Sudan grass yield and germination, and verify the enrichment effect of culture medium with tryptophan, which leads on the rhizobium/plant interaction. Experiments in vitro and greenhouse conditions were conducted. In millet, the inoculation with VP16 grown in culture medium with or without tryptophan induces greater length of hypocotyl and epicotyl under in vitro conditions. UFRGS Lc348 treatment induces longer hypocotyls of millet under in vitro conditions. No effects were observed with the millet inoculation in greenhouse. In Sudan grass, inoculation with VP16 enriched with tryptophan increased dry matter in shoots of adult plants. In millet seedlings had achieved an increasing in elongation in vitro conditions, which could represent an adaptive advantage in the search for water and nutrients in the rhizospheric environment during the initial growth of millet. Similarly, if verified in field conditions, Sudan grass had achieved an increasing in greenhouse conditions with the inoculation of tryptophan-enriched VP16, which could be correlated with a significant gain in crop yield. Therefore, these relationships between tryptophan-enriched VP16 and Sudan grass should be verified in subsequent studies under field conditions.

RESUMO O objetivo do presente estudo foi determinar a melhor densidade e arranjo do tomateiro tutorado verticalmente para a pulverização mecanizada. Foram realizados dois experimentos nas safras 2013/14 e 2014/15 em Calmon-SC. Na safra 2013/14, o delineamento experimental foi em blocos ao acaso com arranjo fatorial 4x2, sendo combinados quatro densidades de plantas (10.753, 12.903, 16.129 e 21.505 plantas/ha) e dois arranjos de plantas tutoradas verticalmente (fila simples e fila dupla). Na safra 2014/15, o delineamento experimental foi em blocos ao acaso com arranjo fatorial 5x2, representado pela combinação de cinco densidades de plantas (10.753, 12.903, 16.129, 21.505 e 32.258 plantas/ha) e de dois arranjos de plantas tutoradas verticalmente (fila simples e fila dupla). Avaliou-se a produtividade total, comercial (extra AA e extra A) e descarte, a massa média de frutos comerciais (extra AA e extra A), a severidade de doenças foliares e procedeu-se a análise econômica dos tratamentos. O arranjo de plantas em fila dupla, para a pulverização mecanizada do tomateiro, proporcionou maior produtividade de frutos comerciais e com maior porcentagem de frutos de melhor classificação, em comparação ao arranjo de plantas em fila simples. A máxima produtividade de frutos foi obtida na densidade de aproximadamente 34.000 plantas/ha, embora a densidade em que se obtém o maior retorno econômico é estimada em 23.000 plantas/ha. As maiores severidades de mancha bacteriana e septoriose foram observadas no arranjo de plantas em fila dupla, em relação ao arranjo de plantas em fila simples. O aumento da densidade de plantas aumentou a severidade de mancha bacteriana e de pinta preta.

ABSTRACT We aimed to determine an adequate planting density and arrangement for the mechanized spraying of vertically staked tomatoes. Two experiments were carried out in the 2013/14 and 2014/15 harvests in the city of Calmon, state of Santa Catarina, Brazil, both in randomized block design. In 2013/14, treatments were arranged in a 4x2 factorial, corresponding to four planting densities (10,753, 12,903, 16,129 and 21,505 plants/ha) and two planting arrangements (single and double rows). In 2014/15, treatments were arranged in a 5x2 factorial, corresponding to five plant densities (the same planting densities of the previous harvest beyond 32,258 plants/ha) and the same planting arrangements. Total, marketable (considering extra AA and extra A fruits as marketable) and unmarketable yield, the average mass of marketable fruits and severity of leaf diseases were evaluated. Economic analysis was also performed. For tomatoes grown under mechanized spraying, double row plantings resulted in higher yield of marketable fruits and a higher percentage of top grade fruits compared to single row plantings. Maximum fruit yield was reached at approximately 34,000 plants/ha, although maximum revenue was estimated for 23,000 plants/ha. Bacterial spot and Septoria leaf spot severity were higher in double rows than in single rows. Increases in planting density resulted also in increases in bacterial spot and early blight severity.

Resumo Este estudo investigou a dieta de quatro caracídeos [Hyphessobrycon eques (Steindachner, 1882), Odontostilbe pequira (Steindachner, 1882), Psellogrammus kennedyi (Eigenmann, 1903) e Serrapinnus calliurus (Boulenger, 1900) ], que coexistem em duas lagoas, e verificaram-se possíveis diferenças espaciais no fitness dessas populações. O objetivo principal foi analisar se essas espécies demonstram melhor fitness de acordo com o valor nutricional do recurso consumido. Desta forma, espera-se que as espécies demonstrem melhores condições nutricionais (demonstrado pelo fator de condição relativo) durante o forrageamento de itens de origem animal, assim como o contrario é esperado ao consumir itens de origem vegetal e detritos. A amostragem foi realizada em agosto de 2011. A dieta foi avaliada através da análise do conteúdo estomacal e o fator de condição relativo foi calculado para cada indivíduo amostrado, obtendo-se um valor médio para cada população. As espécies exibiram elevada plasticidade alimentar; H. eques e P. kennedyi alteraram a maioria dos itens alimentares de suas dietas entre as lagoas estudadas. Apesar destas variações, o fator de condição não variou espacialmente para qualquer espécie. Os resultados indicam que estas espécies possuem adaptações fisiológicas que lhes permitem obter o máximo de energia a partir do alimento, mesmo que tenha baixo valor nutricional, ou que o peixe pode compensar o consumo de alimentos com baixo valor nutricional, aumentando a taxa de consumo. Assim, independentemente do tipo de recursos consumidos, estes recursos cumpriram as necessidades metabólicas dos peixes nas lagoas estudadas.

Abstract This study investigated the diet of four characids [Hyphessobrycon eques (Steindachner, 1882), Odontostilbe pequira (Steindachner, 1882), Psellogrammus kennedyi (Eigenmann, 1903) and Serrapinnus calliurus (Boulenger, 1900) ] coexisting in two lagoons and checked for possible spatial differences and the influence on population fitness. The main goal was check if these species show better fitness according to the nutritional value of the food resource consumed. In this way, it is expected that the species show improved nutritional conditions (evidenced by the relative condition factor) when foraging for items of animal origin, and the reverse is expected when consuming items of plant origin and detritus. Sampling was conducted in August 2011. The diet was evaluated by analyzing contents and calculating the relative condition factor for each sampled individual, obtaining a mean value for each population. Species exhibited high food plasticity; H. eques and P. kennedyi altered most their diets from a lagoon to another. Despite these variations, the condition factor showed no significant spatial variation for any species. The results indicated that these species have physiological adaptations that allow them to obtain the maximum energy from food, even if it has low nutritional value, or that fish can compensate for the consumption of low nutritional food by increasing the consumption rate. Thus, regardless of the type of resources consumed, these have met the metabolic needs of the fish in the studied lagoons.

ABSTRACT Rhizobia and associative bacteria promote growth in rice plants (Oryza sativa L.) through a series of mechanisms, but most studies on inoculation have been performed based on inoculation with these bacteria in a separate or singular manner. The objective of this study was to assess the efficiency of single/isolated inoculation and inoculation combined with symbiotic rhizobia from forage legume and with Azospirillum brasilense on promoting growth and the root colonization process in wetland rice. Two rhizobia among four isolates from a greenhouse and a laboratory experiment were selected that efficiently promoted seed germination and rice plant growth in a sterilized substrate and in soil. The two most efficient isolates (UFRGS Vp16 and UFRGS Lc348) were inoculated alone or in combination with a commercial product containing A. brasilense in two field experiments using two wetland rice cultivars over two growing seasons. In the field experiments, these isolates coinoculated with A. brasilense promoted larger increases in the agronomic variables of wetland rice compared to the control without inoculation. Confocal laser microscopy confirmed the presence of inoculated bacteria tagged with gfp (UFRGS Vp16, UFRGS Lc348, and A. brasilense) colonizing the root surface of the rice seedlings, mainly in the root hairs and lateral roots.