Seed Quality and Vigor of Germination of Moringa oleífera Lam. in Saline Stress

Abstract Moringa oleifera Lam., is a tree species that has several purposes of use, standing out in the recovery of degraded areas and the use of seeds as biodsorbents in water clarification. However, ony a little is known about the behavior of seed germination under saline conditions, common in soils and water in the Brazilian Northeast. Thus, the objective was to evaluate the increment of water during the soaking and seed germination of M. oleífera that were submitted to different electrical conductivity of the irrigation water. The work was developed following a completely randomized design, with stress simulation employing saline solutions at the concentrations of 0.0; 3.0; 6.0 and 9.0 dS m-1. To determine the soaking curve, the water increment of the soaked seeds in the different saline solutions was monitored at regular intervals with four replications per treatment. To characterize the physiological quality of the seeds, the percentage, first count, speed index, average time and average germination speed were evaluated. The M. oleífera is tolerant to the effect of salinity during the germination phase, however seed vigor is reduced as a function of increased salinity. Soaking the seeds makes begin the phase II of the germination process around 10 hours and extends for up to 50 hours, when phase III begins, they absorb approximately 0.2 g of water and require 86 hours for germination. Salinity reduces the absorption and increase of water in the seeds.

Tolerance to irrigation water salinity in physalis plants: productive aspects / Tolerância à salinidade da água de irrigação em plantas de fisális: aspectos produtivos

The cultivation of non-traditional fruits has gained ground in the horticulture sector, but which, in certain situations, are plants that require previous studies related to soil adaptability, climate, and irrigation water quality. In this sense, this work aimed to evaluate the effects of irrigation water salinity on Physalis peruviana L. (fisális) plants in the different growth phases. The experimental area was installed on the premises of the Federal University of Campina Grande, adopting a casualized block design, with four saline levels of irrigation water (0.3; 1.2; 2.1 and 3.0 dS m-1) and five repetitions per treatment. The variables analyzed were: stem diameter, plant height and number of leaves every 15 days, leaf area at 55 days after transplanting, number of side branches, number of flower buds, number of flowers, average fruit weight, polar diameter, and equatorial diameter of fruits, number of fruits per plant and productivity. According to the results, the plants were tolerant to saline levels of irrigation water of up to 3.0 dS m-1, without prejudice to the phenological and productive characteristics of the crop. The unitary increase in the salinity of the irrigation water did not result in damage to the physiological characteristics of the plants until the 60 days of transplanting. (AU)

O cultivo de frutas não tradicionais tem ganhado espaço no setor de hortifrútis, mas que, em determinadas situações, são plantas que requerem estudos prévios relacionados a adaptabilidade de solo, clima e qualidade da água de irrigação. Neste sentido, este trabalho teve como objetivo avaliar os efeitos da salinidade da água de irrigação em plantas de Physalis peruviana L. (fisális) nas distintas fases de crescimento. A área experimental foi instalada nas dependências da Universidade Federal de Campina Grande, adotando o delineamento em blocos casualizados, com quatro níveis salinos da água de irrigação (0,3; 1,2; 2,1 e 3,0 dS m-1) e cinco repetições por tratamento. As variáveis analisadas foram: diâmetro do caule, altura das plantas e número de folhas a cada 15 dias, área foliar aos 55 dias após o transplantio, número de ramos laterais, número de botões florais, número de flores, peso médio dos frutos, diâmetro polar e diâmetro equatorial dos frutos, número de frutos por planta e produtividade. Conforme os resultados, as plantas se mostraram tolerantes a níveis salinos da água de irrigação de até 3,0 dS m-1, sem prejuízos nas características fenológicas da cultura e produtivas. O aumento unitário da salinidade da água de irrigação não resultou em danos nas características fisiológicas das plantas até os 60 dias de transplantio. (AU)

Effects of irrigation water salinity and salicylic acid on germination and vigor of Mesosphaerum suaveolens (L. ) Kuntze / Efeitos da salinidade da água de irrigação e do ácido salicílico na germinação e no vigor de Mesosphaerum suaveolens (L. ) Kuntze

Salinity is one of the factors that negatively impact plant growth and productivity; therefore, it is necessary to seek solutions that help mitigate the degenerative action of saline stress on crops. The objective of this study was to evaluate the effects of salicylic acid (SA) on the germination and vigor of Mesosphaerum suaveolens (L.) Kuntze seeds subjected to salinity. The experiment was carried out using a completely randomized design, in an incomplete 5 × 5 factorial scheme, with five levels of electrical conductivity of irrigation water (ECw - 0.0, 1.45, 5.00, 8.55, and 10.00 dS m-1) and five doses of SA (0.0, 0.29, 1.00, 1.71, and 2.00 mM), with four replications of 50 seeds, totaling nine combinations generated via a central composite design. The germination percentage, first germination count, germination speed index, average germination time, percentage of abnormal seedlings, shoot, root, and seedling lengths, and total seedling dry mass were evaluated. Salicylic acid attenuated the effect of saline stress on initial growth, mitigating damage to root and shoot lengths. Seed priming with salicylic acid improved germination and seed vigor.(AU)

A salinidade é um dos fatores que promove a inibição no crescimento e produtividade vegetal, sendo necessária a busca por alternativas que auxiliem na mitigação da ação degenerativa do estresse salino às culturas. Objetivou-se com este trabalho avaliar doses de ácido salicílico na germinação e vigor de sementes de Mesosphaerum suaveolens (L.) Kuntze submetidas à salinidade. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial incompleto 5 x 5, com cinco níveis de condutividade elétrica da água de irrigação (CEa de 0,0; 1,45; 5,00; 8,55 e 10,00 dS m-1) e cinco doses de AS de (0,0; 0,29; 1,00; 1,71 e 2,00 mM L-1), com quatro repetições de 50 sementes, totalizando nove combinações geradas via matriz Composto Central de Box. As variáveis avaliadas foram: porcentagem de germinação, primeira contagem de germinação, índice de velocidade de germinação, tempo médio de germinação, porcentagem de plântulas anormais, comprimento da parte aérea, radícula e plântula e massa seca total de plântulas. O ácido salicílico atenua o efeito do estresse salino sobre o crescimento inicial, mitigando os danos sobre o comprimento de radícula e da parte aérea. O tratamento das sementes com ácido salicílico melhora a germinação e o vigor das sementes.(AU)