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A B S T R A C TThis study assessed the effect of different substrates and addition of nutrient solution on the production of Pochota fendleri seedlings, leaf contents of macro and micronutrients and chlorophyll a and b. The experimental design was completely randomized, in a 3 x 2 factorial scheme, with four replicates. The factors were three substrates, with or without addition of nutrient solution, composing six treatments: (T1) = sand; (T2) = soil; (T3) = sand + soil (1:1); (T4) = sand + nutrient solution; (T5) = soil + nutrient solution; (T6) = sand + soil + nutrient solution. Growth characteristics (height, collar diameter, shoot dry matter, root dry matter, root/shoot ratio and total dry matter) and contents of macro-and micronutrients and chlorophyll a and b were evaluated. The use of nutrient solution reduces the time to obtain seedlings of Pochota fendleri, and it is important for proper growth and quality of seedlings. The sequence of nutritional requirement presented by Pochota fendleri seedlings in three substrates with addition of nutrient solution follows the descending order: macronutrients (N > Ca > K > Mg > P > S) and micronutrients (Fe > Mn > B > Zn > Cu).Solução nutritiva e substratos para produção de mudas de cedro doce (Pochota fendleri) R E S U M OObjetivou-se, neste trabalho, verificar o efeito da adição de solução nutritiva em diferentes substratos na produção de mudas de Pochota fendleri, e seu efeito nos teores de macro e micronutrientes e de clorofilas a e b nas folhas. O delineamento experimental utilizado foi inteiramente casualizado em esquema fatorial 3 x 2, com quatro repetições. Os fatores foram três substratos e adição ou não de solução nutritiva, compondo seis tratamentos: (T1) = areia; (T2) = solo; (T3) = solo + areia (1:1); (T4) = areia + solução nutritiva; (T5) = solo + solução nutritiva; (T6) = solo + areia + solução nutritiva. Foram avaliadas características de crescimento (altura, diâmetro do colo e massa seca da parte aérea e radicular, relação raiz/ parte aérea e massa seca total), além dos teores de macro e micronutrientes e de clorofilas a e b. A utilização de solução nutritiva reduz o tempo para obtenção de mudas de Pochota fendleri e é importante para o crescimento e qualidade das mudas. A sequência de exigência nutricional das mudas nos três substratos com adição de solução nutritiva segue em ordem decrescente: macronutrientes (N > Ca > K > Mg > P > S ) e micronutrientes (Fe > Mn > B > Zn > Cu).

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Plants can be attacked by a wide variety of herbivores. Thus, developing protective mechanisms for resistance against these agents is an advantage for survival and reproduction. Over the course of evolution, many resistance mechanisms against herbivory have been developed by the plants. Induced direct and indirect resistance mechanisms can manifest in plants after herbivore attack. The two-spotted spider mite Tetranychus urticae is not a pest of maize crops (Zea mays), despite being reported infesting plants that may have resistances against this herbivore. We tested the hypothesis that maize plants would be able to induce direct resistance against T. urticae after, evaluating the effect of T. urticae infestation in maize plants on the development and reproduction of conspecifics. We tested induced direct resistance performing infestation and measuring biological parameters upon a second infestation. Maize plants, 40 days after sowing, were divided into two groups: 30 not infested by T. urticae (clean plants clean) and, 30 infested by the spider mite. Infestation of maize plants by T. urticae reduced the conspecific female adult survival. However, no change in the survival of immature or reproduction was observed. These results suggest the induction of induced direct resistances in maize by T. urticae. This is first report of direct resistance induction in Z. mays by the two-spotted spider mite T. urticae.

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