RESUMO A rustificação surge como uma estratégia interessante a fim de melhorar a qualidade das mudas nos viveiros florestais, melhorando a sobrevivência a campo. Assim, o objetivo da pesquisa foi evidenciar alterações fisiológicas resultantes da aplicação de metil jasmonato e flexões caulinares nos três estádios de crescimento em mudas de Eucalyptus urograndis. O experimento foi conduzido em Marechal Cândido Rondon, no Estado do Paraná, e foram utilizadas mudas de Eucalyptus urograndis. Os tratamentos foram constituídos de aplicações semanais de metil jasmonato (MeJA) e imposição diária de flexões caulinares, além do tratamento controle. As análises consistiram na quantificação da rigidez flexural, lignina nos caules e raízes, compostos fenólicos nas folhas e raízes, perda de eletrólitos nas raízes e sobrevivência a campo. Em Eucalyptus urograndis com 100 dias após a emergência (DAE) e nas 3 distâncias utilizadas para avaliação da rigidez flexural, as maiores médias foram observadas em mudas submetidas aos tratamentos químico e mecânico coincidindo com o aumento do teor de lignina no caule. Nas raízes, após a quantificação da perda de eletrólitos, no estádio I, houve redução das médias com a aplicação dos tratamentos. Na fase de campo, não houve diferença significativa estatística entre as avaliações morfométricas a campo e a sobrevivência de mudas, quantificadas a cada 15 dias, até completarem 180 dias do plantio. Ainda, as mudas pertencentes ao estádio I foram perdidas, visto que estas eram muitos jovens e não toleraram as condições estressantes. florestais Assim Rondon Paraná MeJA (MeJA controle flexural 10 DAE (DAE caule 1 18 plantio Ainda perdidas estressantes

ABSTRACT Hardening appears as an interesting strategy to improve the quality of seedlings in forest nurseries, favoring their survival in the field. Thus, the objective of this research was to show the physiological alterations resulting from the application of methyl jasmonate and stem flexion in three stages of growth in Eucalyptus urograndis seedlings. The experiment was carried out in Marechal Cândido Rondon, Paraná, and Eucalyptus urograndis seedlings were used. Treatments consisted of weekly applications of methyl jasmonate (MeJA), daily imposition of stem flexion and a control treatment. Analyzes included quantification of flexural stiffness, lignin content in stems and roots, phenolic compounds in leaves and roots, electrolyte leakage in roots and field survival. In seedlings of Eucalyptus urograndis at 100 days after emergence (DAE) and at the three distances used to evaluate flexural rigidity, the highest averages were observed in seedlings submitted to chemical and mechanical treatments, coinciding with the increase in lignin content in the stem. In the roots, after quantifying the extravasation of electrolytes in Stage I, the means decreased with the application of treatments. In the field phase, there were no statistically significant differences between seedling survival assessments, quantified every 15 days, for a period of 90 days after planting. However, seedlings in Stage I were lost because they were too young and could not tolerate the stressful conditions observed in the field. nurseries Thus Rondon Paraná MeJA, MeJA , (MeJA) treatment stiffness 10 DAE (DAE rigidity treatments phase assessments 1 9 planting However (MeJA

ABSTRACT Hardening is the process of exposing seedlings gradually to field conditions. It improves seedling quality through several strategies, including stem bending and the use of plant regulators. Thus, the objective of the experiment was to quantify the physiological changes resulting from mechanical and chemical hardening in Hymenaea courbaril L. seedlings as a function of seedling growth stages. The experiment was conducted at Marechal Cândido Rondon, PR, in a shade house. The design used was a completely randomized, consisting of three treatments (control, methyl jasmonate and stem bending), with seven replications of 16 seedlings. At the end of the hardening treatments we quantified stem bending stiffness, lignin, phenolic compounds, loss of electrolytes and chlorophyll. The phenolic compounds quantified in the leaves increased with the application of both treatments in seedlings of stages I and II. Furthermore, mechanical hardening favored an increase in chlorophyll at all stages. H. courbaril seedlings from stages II and III would be the most recommended for hardening treatments. Mechanical hardening was the most suitable for Hymenaea courbaril L. seedlings. conditions strategies regulators Thus L Rondon PR house randomized control, control (control bending, , bending) 1 stiffness lignin Furthermore H

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 The forestry production sector uses several strategies to minimize post-planting seedling losses. Some practices can modulate characteristics of interest for plant growth and defense, including changes in the light exposure, reduced watering, fertilization, and chemical or mechanical stimulus. This work quantified morphophysiological changes on Schinus terebinthifolius and Cedrela fissilis seedlings resulting from the application of salicylic acid for eight weeks. The experimental design was completely randomized, composed of four treatments (0, 100, 200, and 300 mg L-1 of salicylic acid). The quantified variables included height, diameter, and dry matter mass of the root and aerial parts. Additionally, leaf area, root-cell electrolyte loss, lignin content in roots, and stem plus phenolic compounds were quantified. On aroeira seedlings, the height, aerial, and radicular dry matter masses and leaf area were reduced while the diameter and the lignin content increased directly as a function of salicylic acid doses. In cedro seedlings the dose of 100 mg L-1, however, resulted in a better balance of plant biomass and would, therefore, be the most indicated dose for the species. The application of salicylic acid for 8 weeks on seedlings of both species resulted in the most relevant morphophysiological modifications correlated with quality characteristics of seedlings of woody species.

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.