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RESUMO -O teste de condutividade elétrica pode proporcionar informações importantes e complementares sobre o potencial fisiológico de sementes em período de tempo relativamente curto, visto que o teste de germinação se completa aos 28 dias para sementes de maracujá. Dessa forma, o objetivo deste trabalho foi avaliar a eficiência do teste de condutividade elétrica na avaliação do potencial fisiológico e padronizar a metodologia para sementes de maracujá-amarelo. Quatro lotes de sementes foram submetidos aos testes de germinação e vigor (primeira contagem, envelhecimento acelerado, índice de velocidade de germinação e emergência de plântulas em casa de vegetação), incluindo o teste de condutividade elétrica, conduzido com 25 e 50 sementes imersas em 50 e 75 mL de água desionizada,e as leituras realizadas após três, seis, nove, 12 e 24 h de embebição. Somente o lote 2 apresentou comportamento de baixo vigor apontado pelos testes de primeira contagem, emergência de plântulas e condutividade elétrica. A determinação do vigor de sementes de maracujá-amarelo por meio do teste de condutividade elétrica pode ser realizada utilizando 50 sementes e 75 mL após 24 h de embebição. Termos para Indexação: Passiflora edulis Sims f. flavicarpa Deg., testes de vigor, germinação, lixiviação, padronização. ELETRICAL CONDUCTIVITY TEST FOR YELLOW PASSION FRUIT SEEDSABSTRACT -The electrical conductivity test can provide important and complementary information on the physiological potential of seeds in a relatively short period of time, unlike the germination test which is completed in 28 days for yellow passion fruit seeds. Thus, the objective of this study was to evaluate the efficiency of the electrical conductivity test and to standardize the methodology to be for seeds of yellow passion fruit. Four seed lots were tested for germination and vigor (first count, accelerated aging, speed germination index and seedling emergence in green-house) including the electrical conductivity test, conducted with 25 and 50 seeds immersed in 50 and 75 mL of dionized water and the readings taken after 3, 6, 9, 12 and 24 hours of soaking. Only lot 2 showed reduced vigor appointed by the first count test, seedling emergence and electrical conductivity test. The vigor determination of yellow passion fruit through the electrical conductivity test can be performed using 50 seeds in 75 mL of dionized water, with 24 hours of soaking.

The importance of biotechnology involved in the availability of nutrients to plants in different production systems is well known. In the search for agricultural sustainability, biological nitrogen fixation process stands out, especially in tropical regions where soil organic matter can be rapidly mineralized. In this aspect, researches have pointed out the potentialities of the use of diazotrophic bacteria, as well as other growth-promoting bacteria in Poaceae. Maize crop, especially, stands out in the international scenario, requiring a deepening of the research aiming to raise the contribution potential of microorganisms including Azospirillum spp. in reducing the consumption of fertilizers from nonrenewable sources while promoting an increase in agricultural productivity and mitigating environmental impacts.

Lettuce (Lactuca sativa) is among the most widely cultivated leafy vegetables. Its production is in continuous expansion, with an increase of 491,000 tonnes, on average, in recent years (FAOSTAT, 2020). However, Bremia lactucae, the causal agent of lettuce downy mildew (LDM), considered one of the main leaf diseases of lettuce in the world, can infect any stage of plant development and cause extensive production losses (Spring et al., 2018;Van Hese et al., 2016).In Brazil, losses due LDM can reach up to 70% under conducive weather (author's unpublished observations). Disease symptoms include development of light green to yellow areas on the upper side