Maize seeds submitted to thermotherapy and analyzed by dynamic speckle

The quality of the seeds used for sowing is fundamental for a high productivity and quality of the crop. Therefore, eradicating pathogens is essential for the plant to develop in the best possible way. The eradication of those pathogens can be accomplished by means of treatments that consist of the application of substances to the seeds or by performing physical procedures. Thermotherapy is a physical treatment, in which the seed is exposed to a given thermal energy, such as heated air or steam, and can be highly efficient for controlling those pathogens, in addition to reducing environmental damage and costs. The present work aimed to evaluate the efficiency of thermotherapy in two ways: wet heat (water) and dry heat (water vapor), both at 60 °C, alternating the exposure time to the thermal sources. The treatment with humid heat with a time of exposure of 5 min was the most efficient, since it presented higher germination percentages (83%) and less occurrence of Fusarium sp. (33%). It was observed that the most efficient thermotherapy is in the control of Fusarium, the most aggressive is for the quality of the seed. The quality of the treatments was evaluated through standard methodologies, according to the rules for seed analysis, such as germination and sanitation tests. Biospeckle laser was used to identify the microbial activity in these seeds, through activity maps generated by laser speckle contrast analysis (LASCA) processing. In this way, the research involving thermotherapy can be done by varying the temperature and the time of exposure to obtain values that considerably reduce the pathogenic agents and preserve the quality, in order to maintain the values of germination and vigor acceptable for commercialization.811512

The International Natural Product Sciences Taskforce (INPST) and the power of Twitter networking exemplified through #INPST hashtag analysis

Background: The development of digital technologies and the evolution of open innovation approaches have enabled the creation of diverse virtual organizations and enterprises coordinating their activities primarily online. The open innovation platform titled "International Natural Product Sciences Taskforce" (INPST) was established in 2018, to bring together in collaborative environment individuals and organizations interested in natural product scientific research, and to empower their interactions by using digital communication tools. Methods: In this work, we present a general overview of INPST activities and showcase the specific use of Twitter as a powerful networking tool that was used to host a one-week "2021 INPST Twitter Networking Event" (spanning from 31st May 2021 to 6th June 2021) based on the application of the Twitter hashtag #INPST. Results and Conclusion: The use of this hashtag during the networking event period was analyzed with Symplur Signals (https://www.symplur.com/), revealing a total of 6,036 tweets, shared by 686 users, which generated a total of 65,004,773 impressions (views of the respective tweets). This networking event's achieved high visibility and participation rate showcases a convincing example of how this social media platform can be used as a highly effective tool to host virtual Twitter-based international biomedical research events

In vitro sensibility of Phomopsis sojae and Phomopsis phaseoli f. sp. meridianalis to fungicides and effect in soybean (Glycine max) seed treatments inoculated with both pathogens

O presente trabalho teve como objetivo avaliar a eficiência de produtos para o controle de Phomopsis sojae e Phomopsis phaseoli f. sp. meridionalis através de testes de fungitoxicidade in vitro e in vivo. No teste in vitro foram utilizados 4 isolados de P. sojae e 4 isolados de P. phaseoli f. sp. meridionalis. Foram comparados 14 fungicidas quanto à eficiência na porcentagem de inibição do crescimento micelial (PIC), com 0, 1, 10 e 100 ppm do ingrediente ativo. Através do cálculo da ED50 ( dose necessária para inibir em 50 % crescimento micelial), foram considerados altamente eficientes (ED50 < 1 ppm), para ambos os patógenos, os produtos benomyl, carbendazin, thiabendazole e difenoconazole; além desses, o quintozene também se destacou, apesar de sua eficiência ter variado conforme o isolado. Observou-se, de uma maneira geral, uma menor sensibilidade dos isolados de P. sojae, concluindo-se que os produtos adequados para esse patógeno o são também para P. phaseoli f. sp. meridianalis. Para a realização dos testes in vivo foi escolhido um isolado de cada patógeno, usando-se como critério o que apresentou maior ED50 (mais tolerante) para todos os produtos químicos comparados in vitro. As sementes do cultivar IAC 14, altamente suscetível a P. phaseoli f. sp. meridianalis, foram inoculadas artificialmente pelo método do contato, com os dois patógenos, sendo depois tratadas com os seguintes fungicidas e doses (g i.a./100 kg sementes): benomyl (50), carbendazin (50), thiabendazole (20), difenoconazole (5) e quintozene (225). O teste de sanidade (pelo método do papel de filtro) foi avaliado aos 7, 10 e 13 dias, contando-se o número de picnídios e picnídios + micélio típico. Os melhores tratamentos, que não diferiram entre si, foram benomyl, carbendazin e thiabendazole. Na testemunha, a incidência foi de 98 % para ambos os patógenos, considerando-se picnídios + micélio típico, aos 1 O ou 13 dias de incubação. No teste de germinação, somente sementes inoculadas com P. sojae mostraram diferença significativa em relação as sementes não inoculadas e não tratadas. Os demais tratamentos não diferiram entre si para ambos os patógenos. A emergência não foi afetada por nenhum tratamento, para ambos os patógenos. Esses resultados indicam que a importância do tratamento químico de sementes, principalmente para o agente causal do cancro da haste, está relacionada com a não introdução desse patógeno em áreas livres do mesmo. Dentre os fungicidas e doses comparadas, deve-se recomendar o tratamento de sementes de soja portadoras de P. sojae e P. phaseoli f. sp. meridianalis com benomyl, carbendazin ou thiabendazole.The present study was carried out to evaluate different fungicides for the control of Phomopsis sojae and Phomopsis phaseoli f. sp. meridianalis through in vitro and in vivo fungitoxicity tests. In the in vitro test, 4 isolates of P. sojae and 4 isolates of P. phaseoli f. sp. meridionalis were used. Fourteen fungicides were compared for their efficiency in inhibiting the micelial growth of the pathogens on PDA containing 0, 1, 10 and 100 ppm of the active ingredients. By calculating the ED50 (dose required for inhibiting 50 % of the micelial growth), benomyl, carbendazin, thiabendazole and difenoconazole were considered highly efficient (ED50 < 1 ppm). Although its efficiency was variable among the isolates, quintozene showed superior among others fungicidess. P. sojae was, in general, less sensible to the fungicides than P. phaseoli f. sp. meridionalis, although both pathogens showed similar pattems of responses to the fungicides. One isolate of each pathogen was chosen for in vivo tests, according to the higher ED50 values obtained for all products tested. Seeds of the cultivar IAC 14, which is highly susceptible, were inoculated with both pathogens through the contact method and subsequently treated with the following fungicides and doses (g a.i./100 kg of seeds): benomyl (50), carbendazin (50), thiabendazole (20), difenoconazole (5) and quintozene (225). The health test performed through the blotter method was evaluated at 7, 10 and 13 days of incubation, by counting the number of pycnidia and pycnidia + typical mycelium. The best treatments, which were not different among themselves, were benomyl, carbendazin and thiabendazole. No treated seeds showed an incidence of 98 % for both pathogens, considering pycnidia + typical mycelium, at 10 or 13 days of incubation. ln the germination test only inoculated seeds with P. sojae showed diferences in relation to the seeds not inoculated and not treated with fungicides. Others treatments did not show differences in relation to both pathogens. Emergency was not affected by both pathogens or fungicide treatments. Results indicate that importance of the chemical treatment of the seeds is related with the non introduction of the pathogen to areas free of the pathogen. According to the results obtained, seeds containing P. sojae and P. phaseoli f. sp. meridianalis should be treated with benomyl, carbendazin or thiabendazole

Association of fungi and viability of seeds of Inga vera subsp. affinis (DC.) T.D. Penn. during storage

Orientadores: João Domingos Biagi, Claudio José BarbedoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia AgrícolaResumo: O elevado metabolismo dificulta a manutenção da viabilidade de sementes de Inga vera. As principais estratégias para a conservação dessas sementes durante o armazenamento consistem na desidratação parcial, na adição de ácido abscísico, no uso de solução de polietileno glicol e de baixas temperaturas. Contudo, tais condições ainda podem conduzir à deterioração, tanto pela atividade do seu próprio metabolismo, como pelo desenvolvimento de micro-organismos favorecidos pela umidade. Desta forma, o presente trabalho teve como objetivo analisar o grau de interferência dos fungos no metabolismo respiratório dos embriões de Inga vera com diferentes níveis de hidratação e a eficiência do tratamento com fungicidas, visando à manutenção da viabilidade durante o armazenamento. Para tanto, os embriões foram obtidos em três anos, sendo em 2009 colhidos em duas fases distintas de maturação (imaturos e maduros), submetidos a dois níveis de secagem, tratados ou não com carboxin + thiram e armazenados sob 7 e 25 oC por até 65 dias. Em 2010, foram colhidos maduros, submetidos a quatro níveis de secagem, tratados ou não com carbendazin + thiram e armazenados a 7 ºC por 120 dias. Nos experimentos de avaliação da respiração, os embriões obtidos em 2010 foram tratados ou não com carbendazin + thiram, mortos ou não por congelamento e inoculados ou não com Aspergillus flavus. Os colhidos em 2011 foram mantidos sem secagem e tratados ou não com carbendazin + thiram e a respiração foi avaliada a 7 e a 25 ºC. Constatou-se que a incidência de fungos, principalmente Fusarium oxysporum, juntamente com o teor de água e a temperatura influenciam nas taxas respiratórias dos embriões de I. vera maduros e que o tratamento com carbendazin + thiram, na dose de 80 mL do produto comercial para 100 kg de embriões, é eficiente na manutenção da viabilidade de embriões maduros e sem secagem, a 7 ºC por 120 dias. Pestalotiopis sp., Phoma sp., Phomopsis diachenii e Colletotrichum gloeosporioides aparecem durante o armazenamento, simultaneamente à deterioração dos embriões de I. vera. O desenvolvimento de fungos em embriões de I. vera difere do padrão clássico definido com base em sementes ortodoxasAbstract: The high metabolism hinders the maintenance of Inga vera seeds viability. The main strategies for the conservation of these seeds during storage consist of the partial dehydration, addition of abscisic acid, use of polietileno glicol solution and of low temperatures. However, such storage conditions can lead to further deterioration of the seed, either by the activity of its own metabolism, as the development of microorganisms favored by moisture. This study aimed to analyze the degree of interference of fungi on the respiratory metabolism of Inga vera embryos with different levels of hydration and the efficiency of fungicide treatment, as maintaining these embryos viability during storage. The embryos were obtained in three years. In 2009 they were collected in two distinct stages of maturation (immature and mature), subjected to two drying levels, treated or not treated with carboxin + thiram and stored at 7 and 25 º C for up to 65 days. In 2010 the embryos were collected mature, subjected to four drying levels, treated or not treated with carbendazin + thiram and stored at 7 º C for 120 days. In the experiments carried out to evaluate the respiration, the embryos obtained in 2010, were treated or not treated with carbendazin + thiram, killed or not by freezing and inoculated or not with Aspergillus flavus. The embryos collected in 2011 were kept without drying, treated or not treated with carbendazin + thiram and respiration was evaluated at 7 and 25 ° C. It was found that the incidence of fungi, primarily Fusarium oxysporum, together with the water content and temperature influence respiration rates of mature embryos of I. vera and that the treatment with carbendazin + thiram at the dose of 80 mL of the commercial product to 100 kg of embryos is effective for maintaining the viability of mature embryos without drying at 7 ° C for 120 days. Pestalotiopis sp., Phoma sp., Phomopsis diachenii and Colletotrichum gloeosporioides are detected during the storage time, along with the deterioration of the embryos of I. vera. The development of fungi on embryos of I. vera differs from the classic pattern verified for orthodox seedsDoutoradoTecnologia Pós-ColheitaDoutor em Engenharia Agrícol

Fungicide and drying effects on the viability of recalcitrant seeds of Inga vera subsp. affinis

Studies on the health and quality of seeds from native tree species are scarce in the tropics, which is the case of Inga vera, a recalcitrant-seeded Brazilian species used in reforestation. In this study a series of experiments were conducted to analyze the effects of fungicides and hydration levels on the suppression of seed borne fungi and seed physiology. Firstly, three commercially available fungicide formulations (thiram, carbendazim + thiram and carboxin + thiram) for seed treatment were evaluated. Secondly, embryos were subjected to a combination of four drying levels (62, 52, 44 e 34 % water content) with or without fungicide (carbendazim + thiram). All three preliminary screened fungicide formulations were not phytotoxic, with carbendazim + thiram performing best. Seed deterioration was associated with a high incidence of fungi at any level of drying. Fungicide treatment reduced the incidence of the most common fungi (Acremonium curvulum and Phomopsis diachenii) and extended the lifespan of non-dried embryos from 90 to 120 days.4117718

Viability of Inga vera Willd. subsp. affinis (DC.) T. D. Penn. embryos according to the maturation stage, fungal incidence, chemical treatment and storage

The main strategies for conserving Inga vera seeds during storage consist of their partial dehydration and low temperatures. However, such storage conditions can lead to further deterioration of the seed, either from its own metabolism or the development of microorganisms favored by moisture. In this study, the relationship between fungi and the conservation of I. vera embryos with different levels of hydration and maturity was studied, together with the efficiency of treating with carboxin + thiram (300 mL / 100 kg of embryos) for fungus control. Embryos were collected at two stages (immature and mature) and subjected to two drying levels. A sample of embryos from each stage and drying level was treated with carboxin + thiram. Embryos were then stored at 7 or 25 °C for up to 65 days. It was found that undried, mature embryos have a higher physiological quality than the immature ones after storage at 7 °C for 65 days. The carboxin + thiram treatment is phytotoxic for dried embryos. "Field" fungi develop according to the degree of embryo deterioration, differing from the classic pattern defined for orthodox seeds

Health aspects and ideal temperature for germination of peanut seeds

This study was performed to identify the best temperatures for germinating peanut seeds with fungi on a paper substrate. Eleven seed lots from the cultivars IAC-886 and IAC-503 were selected with different levels of fungi. Two of these seed lots with a high rate of Aspergillus spp., Penicillium sp., and Rhizopus sp., as detected by the blotter test method, were used for selecting a fungicide for seed treatment. Considering the active ingredients evaluated, thiram, at the rate of 300 g of commercial product per 100 kg of seeds, was most efficient in controlling fungi, preventing their interference in germination. All the seed lots, treated with this product or not, were subjected to the germination test on rolls of paper at the temperatures of 25 °C, 30 °C, 35 °C, 20-30 °C, 20-35 °C, 25-30 °C, and 25-35 °C. Alternating temperatures of 20-35 °C, 20-30 °C, and 25- 30 °C led to higher germination of peanut seeds, treated with fungicides or not. Constant temperatures are not recommended, because they are more favorable to the development of fungi associated with these seeds than to the germination process, thus underestimating the germination potential of the seeds subjected to the test412233243CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQNão te