A B S T R A C TWater stress is a condition that causes physiological changes in different species and even genotypes of the same species. One of the osmotic agents most used to simulate this condition is polyethylene glycol 6000. The aim of this study was to evaluate the effects of water stress on the physiological quality of seeds and performance of seedlings of crambe genotypes. A completely randomized design was used, in a factorial scheme with two genotypes (one cultivar and one line) and five osmotic potentials simulated with aqueous solutions of polyethylene glycol 6000 (control = 0, -0.25, -0.50, -1.0, -1.50 MPa), with four replicates of 50 seeds per treatment. The effects of the treatments were evaluated by means of germination, first count, germination speed index and fresh and dry matter of seedlings. The physiological quality of seeds and the performance of crambe seedlings are negatively affected under water stress from -0.25 MPa on. Seeds of the genotype FMSCR 1101 have greater tolerance to drought stress, regardless of the osmotic potential used.Qualidade fisiológica de sementes e desempenho de plântulas de genótipos de crambe sob estresse hídrico R E S U M O O estresse hídrico é uma condição que provoca alterações fisiológicas em diversas espécies e até mesmo em genótipos de uma mesma espécie. Um dos agentes osmóticos mais utilizados para simular esta condição é o polietilenoglicol 6000. Objetivou-se, com este trabalho avaliar os efeitos do estresse hídrico na qualidade fisiológica de sementes e no desempenho de plântulas de genótipos de crambe. Utilizou-se o delineamento experimental inteiramente casualizado em esquema fatorial com dois genótipos (uma cultivar e uma linhagem) e cinco potenciais osmóticos simulados com soluções aquosas de polietilenoglicol 6000 (testemunha = 0; -0,25; -0,50; -1,0; -1,50 MPa), em quatro repetições de 50 sementes por tratamento. Os efeitos dos tratamentos foram avaliados por meio dos testes de germinação, primeira contagem de germinação, índice de velocidade de germinação, matéria fresca e matéria seca de plântulas. A qualidade fisiológica das sementes e o desempenho das plântulas de crambe são afetados negativamente sob estresse hídrico a partir de -0,25 MPa. Sementes do genótipo FMSCR 1101 apresentam maior tolerância ao estresse hídrico, independente do potencial osmótico utilizado.

Storage is a fundamental practice in the control of the physiological quality of seeds, as it is a method that can preserve their viability and vigor for a longer period. Thus, the objective of the present study was to evaluate the storage of chickpea seeds in different packagings, environments, and periods. The completely randomized design was used in a 2 × 2 × 4 factorial scheme, corresponding to two types of packaging (hermetic and Kraft® paper), two storage environments (cold chamber environment and conventional environment), and four storage periods (0, 45, 90, and 135 days), with four replicates. The seeds were placed in Kraft® paper bags and hermetic packagings and stored for 135 days in the environments: cold chamber (14.5 °C and relative air humidity of 65%) and conventional environment (no temperature and relative air humidity control). Every 45 days, seeds were subjected to the following evaluations: determination of water content, germination, first germination count and accelerated aging. In general, the maintenance of the physiological quality of chickpea seeds was verified in Kraft® paper packagings and the cold chamber environment. Storage of chickpea seeds in hermetic packaging must be carried out with seeds with 7% moisture, regardless of the storage environment. The packagings maintained the physiological quality of chickpea seeds for up to 45 days, regardless of the storage environment.

To obtain seeds of high physiological quality, it is of paramount importance to define the ideal harvest moment, which oftentimes corresponds to the period when the physiological maturity is reached. This experiment aimed to study the maturation process and determine the best harvest season of maroon cucumber fruits (Liso Gibão cultivar), in order to reach the maximum physiological seed quality. The flowers were labeled during the anthesis and the fruits harvested at 14, 21, 28, 35, 42, 49 and 56 days after the anthesis (DAA). The fruits had their visual aspects registered by photography analysis and, later, the seeds were extracted for physical (water and dry matter contents) and physiological (germination, seedling emergence, emergence speed index, accelerated aging and electrical conductivity) analyses. It was observed that the seeds reach the maximum dry mass (8.08 mg seed-1) between 47 and 49 DAA. However, the seed physiological maturity, characterized by a maximum germination (70 %) and vigor, occurs at 56 DDA. The best season to harvest seeds with a higher physiological quality takes place from 49 to 56 DDA, when the fruits present a yellowish color.

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Resumo: A determinação da maturidade e do momento adequado de colheita são aspectos importantes a serem considerados na produção de sementes de alta qualidade. Objetivo deste trabalho foi estudar o processo de maturação de sementes de pimenta, variedade Dedo-de-moça, com a finalidade de determinar a época de maturidade fisiológica das sementes, bem como a tolerância das mesmas ao retardamento de colheita. A partir de 50% dos botões florais em antese, as flores foram etiquetadas e os frutos foram colhidos aos 30, 45, 60, 75, e 90 dias após a antese (DAA), sendo avaliados quanto à coloração. A qualidade fisiológica das sementes foram avaliadas quanto ao teor de água, massa de matéria seca, germinação, primeira contagem de germinação, índice de velocidade de emergência e envelhecimento acelerado. As sementes atingem o máximo acúmulo de matéria seca (maturidade de massa) aos 74 dias após antese, sendo que a maturidade fisiológica das sementes (máximo de germinação e vigor) ocorre no período de 71 a 81 dias após a antese, que representa uma soma térmica de 1064,28 a 1128,53 graus dias.Palavras-chave -antese, Capsicum baccatum var. pendulum, época de colheita.Abstract -The determination of physiological maturity and the appropriate harvest time are important aspects to be considered in the production of high quality seeds. The objective of this research was to study the process of maturation of pepper seeds, young finger variety, in order to determine the physiological maturity time of the seeds, as well as the tolerance of the seeds to the harvest delay. From 50% of the floral buds in anthesis, flowers were labeled daily and fruits were harvested at 30, 45, 60, 75, and 90 days post anthesis (DAA). At each harvest season, fruits were evaluated for weight and diameter. To determine the physiological quality, seeds were evaluated for water content, dry matter mass, germination, first germination count, rate of emergence and accelerated aging. The seeds reached the maximum accumulation of dry matter (mass maturity) at 74 days after anthesis, and the physiological maturity of the seeds (maximum germination and vigor) occurs in the period from 71 to 81 days after anthesis, which represents a sum Temperatures from 1064.28 to 1128.53 degrees days.Keywords -before and, Capsicum baccatum var. pendulum; harvest season INTRODUÇÃOA pimenta Dedo-de-moça (Capsicum baccatum var. pendulum) pertence à família Solanaceae e ao gênero botânico Capsicum, que envolve as pimentas, pimentões, berinjelas e tomates. É conhecida popularmente como pimenta calabresa sendo bastante consumida no Brasil, dominando assim o comércio das especiarias picantes sendo considerado símbolo da culinária mundial. (CONFORTI et al.,

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Crop strategies focused on the rational use of water are required in semiarid regions. Thus, the objective of this work was to evaluate the physiological quality of maize seeds produced under soil water deficit conditions. Five irrigation water depth were established, based on the field capacity (100, 85, 70, 55 and 40%), to control the available water for two maize hybrids (2B-587 and DKB-390). A randomized block design was used, with a split-plot arrangement and four repetitions. The plots consisted of irrigation water depths, and the subplots consisted of maize hybrids. The seed water concentration, germination, and vigor were determined after the harvest, using data from first germination counting, seedling emergence, germination speed index, seedling length, and accelerated aging, electrical conductivity, and modified cold tests. The maize hybrid DKB-390 showed better physiological potential under the soil water deficit conditions evaluated. The irrigation water depths lower than 70% of field capacity resulted in decreases in soil water contents and affected negatively the physiological quality of the maize seeds produced.