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Micronutrients are used in small amounts by plants and changes in metabolic processes of seeds can improve germination and vigor; however, little is known about the effects of the combination of Zn, Co, and Mo on corn seeds. Thus, the objective of this study was to evaluate the effects of the application of Zn, Co, and Mo on the physiological potential of corn seeds of different sizes and levels of vigor. A randomized 2×2×3 factorial design was adopted, with two levels of vigor (high and low), two seed sizes (18 and 22 mm), and three doses of liquid fertilizer containing micronutrients (0, 2, and 4 mL kg-1). The physiological potential of the seeds was evaluated based on germination and vigor tests. High vigor corn seeds had greater physiological potential compared to low vigor seeds. Regarding size, small seeds (18 mm) had higher percentages of germination and vigor than the large seeds (22 mm). Seed treatment with micronutrients (Co, Mn, and Zn) resulted in improved emergence in the field, shoot length, and dry mass of large and small seeds with the application dose of 2 mL kg-1, and the application dose of 4 mL kg-1 enhanced emergence in the field of large seeds and germination after the cold test of low vigor seeds of both sizes.

Resumo A Physalis peruviana L. é uma pequena fruta reconhecida por apresentar grande importância farmacológica, uma vez que seus frutos apresentam altos teores de vitamina A, C, ferro e fósforo. Práticas culturais, como tutoramento e poda, podem influenciar a arquitetura da planta, de modo que ela obtenha frutos de melhor qualidade. Portanto, o objetivo deste trabalho foi avaliar a qualidade de frutos de Physalis peruviana L. produzidos em diferentes sistemas de tutoramento e poda. O trabalho foi realizado em Londrina-PR utilizando delineamento inteiramente casualizado, em esquema fatorial 4 × 2, contendo quatro tipos de tutoramento (tutoramento UEL, tutoramento “V” invertido adaptado, sem tutoramento e tutoramento vertical) e duas poda (com e sem desbrota), com quatro repetições. As variáveis analisadas foram: largura e altura dos frutos, massa fresca com e sem capulho, coloração (L*, C* e h°), número de frutos por planta, sólidos solúveis, pH e acidez. Os dados foram submetidos à análise de normalidade e homogeneidade e, se atendidos os padrões, foram comparados pelo teste de Tukey, com nível de 5% de probabilidade pelo programa Sisvar, e correlacionados pelo teste de Pearson utilizando o programa estatístico R. Foi possível concluir que plantas conduzidas livremente tiveram os maiores valores de massa fresca de frutos com capulho e que os sistemas de condução proporcionaram maior penetração da radiação solar no dossel, o que favoreceu o acúmulo de açúcares e a intensidade das colorações dos capulhos. Plantas conduzidas nos sistemas de tutoramento UEL – Universidade Estadual de Londrina e “V” invertido adaptado (ambos sem desbrota) obtiveram maiores quantidades de frutos. A desbrota provocou redução no volume de frutos, menores valores de sólidos solúveis, capulhos mais escuros e com maior tendência à coloração amarelada.

-The use of herbicides must be made in a rational way, giving priority to reduce possible adverse effects on subsequent crops. The objective was to evaluate the residual effect of pre-emergent herbicides on growth and initial development as well as the biochemical composition of snap bean seedlings. The experimental design used was the completely randomized, with four replications in factorial scheme 3x4, three snap bean cultivars (Macarrão Favorito, Macarrão Preferido e Macarrão Trepador) and three pre-emergent herbicides, plus a control (without herbicide). Was use the residual doses of pre-emergent herbicides sulfentrazone in 0.3 g ha -1 , diclosulam in the concentrations of 0.126 g ha -1 and imazethapyr in 0.05 g ha -1 . The work was developed in a seeds analyze laboratory with the purpose of minimizing possible adverse effects of the environment. The seeds were sowing on germitest paper moistened with solutions containing the herbicides, with each respective treatment. The following characteristics were evaluated: germination (GER), germination speed index (GSI), seedling length (SL) and seedling dry mass (SDM) and soluble protein content (PROT) in addition to the enzymatic activity of catalase (CAT), peroxidase (PER) and phenylalanine ammonia-lyase (PAL). The phytometric variables SL, SDM, GER and GSI reduced in the presence of herbicides, and for the levels of PROT and enzymatic activity of CAT, PER and PAL there was observed a variation according to the genotype. The sulfentrazone showed up as the product of higher toxicity, as well as the Macarrão Trepador as the genotype with lower tolerance.

Salinity and water deficiency are factors that limit the initial development of crops, directly interfering with the efficiency of food production. Studies on the behavior of cultivable species under stress are important to determine management actions; therefore, the mechanisms involved in post-stress recovery should be investigated. The objective of this study was to evaluate the effect of water and salt stress on enzymatic activity in azuki bean seedlings. The experimental design was a completely randomized, 4 × 6 factorial arrangement (four reagents: CaCl2, KCl, NaCl, and polyethylene glycol 6000 (PEG 6000) × six osmotic potentials: 0.0, -0.2, -0.4, -0.8, -1.2, and -1.6 MPa). The quantification of protein content and analysis of enzyme (catalase, peroxidase, and phenylalanine ammonia-lyase) activity in seedlings were performed on the 10th day after sowing. NaCl is toxic and recovery of azuki bean seedlings was less likely under salt stress owing to reduced enzymatic activity. In contrast, seedlings subjected to KCl treatment showed increased production of antioxidant enzymes.

Snap beans (Phaseolus vulgaris L.) belong to the same species as common beans and require similar management practices. Studies aimed at nitrogen fertilization in pod beans are scarce, but necessary, considering the demand from farmers for greater productivity of these beans. The objective of this study was to evaluate the effects of nitrogen fertilization in various doses and times of application on the snap beans production. The experimental design was completely randomized in a factorial scheme (2×7) + 1, represented by two doses of nitrogen (30 and 60 kg ha-1) and seven fertilization strategies (100% of the dose provided at sowing or phenological stages V3, V4, or R6; split, with 50% at sowing and 50% at V3, 50% at sowing and 50% at V4, or 50% at sowing and 50% at R6), plus a control (no added N). We analyzed stem length, stem basal diameter, number of trefoils, number and mass of commercially viable pods, and number and mass of total pods. Nitrogen fertilization with 30 kg ha-1 N divided 50% at sowing and 50% at V4 or 50% at sowing and 50% at R6 yielded larger and more numerous pods from plants with greater stem diameters.

Physalis peruviana L. is a plant that produces small sweet berries of great nutritional and medicinal importance. This plant is propagated mainly through seeds, which requires information on germination response to temperature and light changes. Thus, the present study aimed to evaluate the use of different temperatures and light wavelengths on the physiological potential of P. peruviana seed batches. The experiment was conducted with seeds from plants cultivated in 2015/15 and 2016/16. The treatments applied were the following: two germination temperatures (constant temperature of 25 °C and alternated between 20/30 °C), two seed batches (2015/15 and 2016/16), and four forms of light exposure during germination (blue, red, white, and dark). The data were analyzed by principal component analysis using the correlation matrix obtained through the standardized mean equal to zero and variance 1 of the parameters evaluated for each treatment. The eigenvalues and eigenvectors of the matrix were obtained using the SAS University Edition® statistical software. The analyzed variables were: Germination test performed on the 7th and 28th day considering root protrusion, normal seedlings, shoot length, root length, and total dry matter mass. The data showed that the seed germination test of Physalis peruviana L. should be performed under a constant temperature of 25 °C, in the presence of light (white, blue, or red). When the option is the application of the test in the dark, it is necessary to use a thermoperiod of 20–30 °C to provide the expression of maximum physiological potential.

Physalis peruviana L., a small fruit belonging to the Solanaceae family, is known for the high vitamins A and C, iron, and phosphorus content. As it presents numerous opportunities for adding value to family producers, it has been gaining space in the consumer market. Characteristics such as fruit size and seed extraction methods can interfere with the physiological potential of the seeds. Thus, the objectives of this study were to evaluate the relationship between fruit size and physiological quality of Physalis seeds and to establish an effective method for the extraction of its seeds. The experiment was conducted at the Phytotechnics Laboratory of the State University of Londrina, using a completely randomized design in a 3×2 factorial scheme, with 4 replications of 50 seeds. The factors consisted of three fruit sizes (small, medium, and large) and two extraction methods (manual and mechanical). The averages obtained were compared using the Tukey test (p ≤ 0.05). After 28 days of germination, the following evaluations were made: percentage of germination, first germination count, germination speed index, length, and dry mass of seedlings. The physiological potential of the seeds was influenced by the size of the fruits. The method of manual seed extraction proved to be superior and more efficient than the mechanical method.