ABSTRACT Growth analysis (GA) is used to quantify plant development based on morphophysiological changes. GA is a practical tool to evaluate nursery techniques to make them more efficient. The objective of this essay was to quantity measure morphophysiological growth variables of Eucalyptus grandis x Eucalyptus urophylla and Hymenaea courbaril (jatoba) container seedlings to characterize growth stages. The essay was conducted in a shade house located in the western state of Paraná. GA analyses were performed at 10-day intervals on seedlings of both species. When evaluating Hymenaea courbaril seedlings results indicated increased values of height, diameter, root and shoot dry biomass up to 130 days after emergence (DAE). Seedling growth stage-based GA were 70, 100 and 130 DAE for the Eucalyptus hybrid and 50, 80, and 110 DAE for jatoba which presented accelerated, intermediate and reduced seedling growth.

Abstract Exogenous application of stress inductors can facilitate and accelerate some biological responses that promote plant defense. The objective of the experiment was to quantify some compounds linked to nitrogen metabolism as a function of the application of salicylic acid in Schinus terebinthifolius seedlings submitted to water deficit. The experiment was constituted of four doses of salicylic acid and three periods of water deficit. Quantifications included levels of nitrate, free ammonium, total soluble amino acids, proteins, proline, glycine-betaine and relative water content. When evaluating the relative water content in seedlings of Schinus terebinthifolius at 8 days, it was observed that the dose of 200 mg L-1. Seedlings showed physiological responses when subjected to doses of salicylic acid of 200 and 300 mg L-1. The increase in concentration of proline and glycine are advantageous, because these substances act as osmoregulators and cell protectors against deficit hydrical.

ABSTRACT Background: During de-pulping of açai (Euterpe oleracea) for juice production in the Amazonia, large amounts of fibrous waste are daily discarded, a promising substrate for production of high-value cellulose nanofibrils. Therefore, this study sought to evaluate the modifications of açai surface fibers submitted to chemical pretreatment steps and compare the quality of nanostructured films produced with different cycles of mechanical nanofibrillation. Results: A 2-hour pretreatment (at 5% of NaOH) followed by two NaOH/H2O2 bleaching steps resulted in fibers with increased length and reduced diameter compared to raw fibers while preserving fiber integrity and cellulose I structure. The increase of fibers’ grinding cycles from 3 (minimum to gel point) to 21 (maximum suspension thickness) resulted in nanofibril films with higher crystallinity properties, uniform thickness, compacted morphology, and smoother surface. Nanofibril films formed after different numbers of passages exhibited similar mechanical strength, but distinct barrier properties. Conclusion: Açaí waste films produced with fibers submitted to 3 grinding cycles can be recommended for packaging applications that demand easily dissolving, such as instantaneous food. Oppositely, açaí fibers subjected to 21 cycles in grinder provide films suitable for water-resistant packaging, ideal for secondary coatings of papers and paperboards.

RESUMO Thielaviopsis paradoxa é fungo do solo, patógeno amplamente distribuído em todo o mundo e capaz de infectar uma ampla gama de hospedeiros. Em palma de óleo é o agente etiológico da podridão basal, uma importante doença que pode causar sérios prejuízos devido à sua severidade e à rápida dispersão do patógeno. O trabalho teve como objetivo avaliar a patogenicidade e caracterizar um isolado de Thielaviopsis sp. em palma de óleo. O isolado de Thielaviopsis sp. foi obtido do estipe de plantas de palma de óleo, com aparentes sintomas de podridão. A patogenicidade foi avaliada em duas cultivares de palma de óleo, o híbrido interespecífico Manicoré e o híbrido intraespecífico Tenera. As mudas foram inoculadas por suspensão de conídios na concentração de 1x107 conídios por mililitro e discos de micélios, com e sem ferimentos na ráquis de folhas. O isolado foi cultivado em meio de cultura BDA para a caracterização morfológica. A análise filogenética foi realizada com base em comparação de sequências das regiões EF-1? e ITS com sequências disponíveis no GenBank-NCBI e analisadas no Mega 6.0. O isolado foi patogênico nas duas cultivares da palma de óleo em mudas previamente feridas, causando sintomas de podridão de coloração marrom, com formação de um halo amarelado na ráquis. Com o progresso da doença, as folhas apresentaram coloração amarelo progredindo para seca até a quebra da ráquis. O isolado de Thielaviopsis sp. apresentou crescimento rápido com velocidade de crescimento micelial de 50,76 mm dia-1 e com dois dias ocupou totalmente a placa de Petri de 90 mm. A colônia, de coloração inicialmente branca, tornou-se negra com a esporulação e produção de dois tipos de conídios: os endoconídios e aleuroconídios. Após as análises filogenéticas, foi possível comprovar a espécie Thielaviopsis ethacetica como agente etiológico da podridão basal da palma de óleo, distinguindo-a da espécie T. paradoxa.

ABSTRACT Thielaviopsis paradoxa is a soilborne fungal pathogen widely distributed worldwide and capable of infecting a wide range of hosts. In oil palm, it is the etiological agent of basal rot, an important disease that can cause serious damage due to its severity and the rapid dispersion of the pathogen. This study evaluated the pathogenicity and characterized an isolate of Thielaviopsis sp. in oil palm. The isolate was obtained from the stem of an oil palm plant with apparent rot symptoms. Pathogenicity was evaluated in two oil palm cultivars, the interspecific hybrid Manicoré and the intraspecific hybrid Tenera. Seedlings were inoculated by conidial suspension at 1x107 conidia per milliliter e mycelial disks, with and without injuries in the leaf rachis. The isolate was grown in PDA culture medium for morphological characterization. Phylogenetic analysis was performed based on comparison of sequences from the EF-1? and ITS regions with sequences available from GenBank-NCBI and analyzed in Mega 6.0. The isolate was pathogenic to the two oil palm cultivars in previously injured seedlings, causing symptoms of brown rot and formation of a yellowish halo in the rachis. As the disease progressed, the leaves showed yellow coloration and dried, resulting in broken rachis. The isolate of Thielaviopsis sp. showed rapid growth with mycelial growth rate of 50.76 mm day-1, covering the 90-mm Petri plate within two days. The colony, initially white, became black with sporulation and produced two types of conidia: endoconidia and aleuroconidia. After phylogenetic analyses, the species Thielaviopsis ethacetica could be proven as the etiological agent of the dry basal rot of oil palm and could be distinguished from T. paradoxa.