ResumoO objetivo deste trabalho foi avaliar diferentes métodos de extração da mucilagem e também substratos na emergência e no desenvolvimento de plântulas de maracujazeiro-amarelo, em câmara de nebulização. Foram utilizados cinco métodos de extração da mucilagem das sementes (água; água + areia; água + cal virgem; liquidificador com lâminas protegidas e fermentação em água) e três tipos de substratos (casca de arroz carbonizada, vermiculita e fibra de coco). O delineamento experimental foi inteiramente casualizado, com cinco repetições, em arranjo fatorial 5 x 3, sendo que cada parcela foi constituída por 25 sementes. Os parâmetros avaliados foram porcentagem de plântulas emergidas, índice de velocidade de emergência, número de folhas, comprimento do caule, comprimento da maior raiz, peso de massa seca das raízes e da parte aérea. Os métodos de extração de mucilagem mais indicados na emergência e desenvolvimento de plântulas de maracujazeiro amarelo são a lavagem das sementes em água e fermentação em água, enquanto que para os substratos, casca de arroz carbonizada e fibra de coco. Palavras-chave: Passiflora edulis, maracujá, sementes AbstractThe object of this work was to evaluate different methods of mucilage extraction and substrates on passion fruit seedling emergence and development, in a mist chamber. Five methods of mucilage extraction were used: water, water + sand, water + virgin whitewash; blender with protected blades and fermentation in water, and three different types of substrates: rice hull, vermiculite and coconut fiber. The experiment had a completely randomized design with five replications in a factorial 5 x 3 scheme (5 extraction methods of seed mucilage and 3 substrates) being each parcel composed of 25 seeds. The parameters evaluated were: seedling emergence, speed of emergence index, leaf number, stem length, longest root length, weight of dry matter of roots and shoots. Water and fermentation in water are the best method for mucilage extraction and rice hull and coconut fiber are the best substrate for passionfruit seedling emergence and development.

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RESUMO -A adubação nitrogenada, além de aumentar a produtividade, pode favorecer a qualidade fisiológica de sementes. O objetivo do trabalho foi avaliar o efeito de doses de adubação nitrogenada em cobertura e de diferentes formas de ureia na qualidade fisiológica de sementes de genótipos de trigo. Foram avaliadas sementes de três genótipos (BRS 208, BRS Pardela e IWT 04008) cultivados sob quatro doses de nitrogênio em cobertura (0, 40, 80 e 120 kg.ha -1 ), provenientes de três formas de ureia (ureia convencional, ureia com inibidor de urease e ureia protegida). A adubação nitrogenada de cobertura foi realizada durante o estádio de perfilhamento, aos 20 dias após a emergência. Avaliaram-se: o teor de nitrogênio nas sementes, massa de 1000 sementes, germinação e vigor (primeira contagem de germinação, teste de frio, emergência de plântulas no campo, massa seca de plântulas, envelhecimento acelerado e condutividade elétrica). A linhagem IWT 04008 e a cultivar BRS Pardela apresentam sementes com qualidade fisiológica superior à cultivar BRS 208. As formas de ureia e as doses de nitrogênio em cobertura não alteram a qualidade fisiológica das sementes de diferentes genótipos de trigo.Termos de indexação: Triticum aestivum L., ureia protegida, inibidor de urease, germinação, vigor de sementes.Forms of urea and nitrogen levels in topdressing on the physiological quality of wheat seeds ABSTRACT -Besides increasing productivity, nitrogen fertilization may have positives effects on seed physiological quality. The objective of this study was to evaluate the effect of different forms and levels of urea in top dressing fertilization on the physiological quality of wheat seed genotypes. Seeds of three wheat genotypes (BRS 208, BRS Pardela and IWT 04008) were evaluated for four levels of nitrogen fertilization (0, 40, 80 and 120 kg.ha -1 ) in three forms of urea (conventional urea, urea with urease inhibitor and protected urea). The nitrogen fertilization was applied during tillering, 20 days after emergence. The seed nitrogen content, 1000 seed mass, germination and vigor (germination first count, cold test, seedling emergence in the field, dry weight of seedlings, accelerated aging and electrical conductivity) were evaluated. The IWT 04008 line and the cultivar BRS Pardela had seeds with a higher physiological quality than those of the cultivar BRS 208. The forms of urea and levels of nitrogen in topdressing did not affect seed physiological quality of the different wheat genotypes.

A study was conducted in the laboratory to test the suitability of soybean [Glycine max (L.) Merrill] pods at different phenological stages of development (R3-R8) on the performance of nymphs and adults of the small green stink bug

Pigeonpea, Cajanus cajan (L.) Millsp. (Leguminosae) was found as a novel food plant of the neotropical brown stink bug, Euschistus heros (F.), in Paraná State, Brazil. Laboratory studies indicated nymphs performing better when fed on immature pods of soybean, Glycine max (L.) Merrill (Leguminosae), than on immature pods of pigeonpea. Female nymphs required 1.7 d less to complete development and tended to have a lower mortality on soybean (17.5%) than on pigeonpea (25.0%). At emergence, fresh body weight was greater on soybean than on pigeonpea. Adult E. heros performed better on soybean than on pigeonpea. After 120 d, ≈35% of adults were alive on soybean and 30% on pigeonpea; 93.3% of females oviposited on soybean, and 73.3% on pigeonpea, with an oviposition delay of ≈17 days on pigeonpea compared to soybean. Fecundity was ≈63% greater on soybean than on pigeonpea, and adult body weight gain for females and males at different ages was ≈6–36% greater on soybean than on pigeonpea. E. heros colonized soybean during January–March, from the pod‐setting and filling stages (R3–R6) to maturity (R7–R8), and pigeonpea during April–June. These results indicate that E. heros has expanded its host range to pigeonpea in Brazil; pods of this plant are suitable food, and can support the insect during autumn‐early winter, after soybean harvest, and before it enters into partial hibernation.