Mn foliar sobre a qualidade sanitária e lignina de sementes de soja convencional e resistente ao glifosato1

Abstract

RESUMO -O Mn pode estar associado à resistência das plantas aos fungos, por meio da lignificação ou inibição direta. Objetivou-se neste trabalho avaliar a aplicação foliar de Mn sobre a incidência de fungos, teores de Mn e de lignina nas sementes de soja oriundas de cultivares convencionais e de suas derivadas transgênicas resistentes ao glifosato (RR). O ensaio foi conduzido na Universidade Federal de Lavras, em blocos casualizados, com três repetições e esquema fatorial 4 x 4 x 2, sendo quatro cultivares de soja, duas convencionais e suas derivadas RR (BRS Celeste e BRS Baliza RR; BRSGO Jataí e BRS Silvânia RR), quatro doses de Mn via foliar (0; 200; 400 e 600 g Mn ha -1 ) e dois estádios de aplicação (R 1 ou R 3 ). Antes e após seis meses de armazenamento, as sementes foram submetidas ao teste de sanidade (Blotter test). Foram determinados os teores de Mn nas sementes e de lignina no tegumento. Verificou-se que a aplicação foliar de Mn proporciona menores incidências de Cercospora kikuchii, Fusarium spp. e Aspergillus spp. nas sementes de soja produzidas. O Mn aplicado via foliar na soja, tanto no estádio R 1 como em R 3 , transloca até as sementes, mas não afeta a produção de lignina no tegumento das mesmas. Os teores de lignina no tegumento das sementes de soja são inferiores nas cultivares convencionais, Celeste e Jataí, em relação às suas derivadas transgênicas resistentes ao glifosato, Baliza RR e Silvânia RR. ABSTRACT -Manganese may be associated with plant resistance to fungi, either through lignification or direct inhibition. The aim of this study was to evaluate the foliar application of Mn on the incidence of fungi and the levels of Mn and lignin in soybean seeds from conventional cultivars and their transgenic glyphosate-resistant derivatives (RR). The test was conducted at the Federal University of Lavras, in the state of Minas Gerais, Brazil, using a randomized block design with three replications in a 4 x 4 x 2 factorial scheme, comprising four soybean cultivars, two conventional and their RR derivatives (BRS Celeste and BRS Baliza RR; BRSGO Jataí and BRS Silvânia RR), four foliar dosages of Mn (0, 200, 400 and 600 g Mn ha -1 ) and two application stages (R 1 and R 3 ). Prior to, and after six months of storage, the seeds were subjected to a health test (Blotter test). The levels of Mn in the seeds and lignin in the seed coat were determined. It was found that foliar application of manganese affords a lower incidence of Cercospora kikuchii, Fusarium spp. and Aspergillus spp. in the soybean seeds produced. Foliar applications of Mn in the soybean, both at the R 1 and R 3 stages, translocates to the seeds, but does not affect lignin production in the seed coat. Levels of lignin in the seed coat of the soybean are lower in the conventional cultivars, Celeste and Jataí, in relation to their transgenic glyphosate-resistant derivatives, Baliza RR and Silvânia RR. Palavras

Sulfur-Induced Resistance against Pseudomonas syringae pv. actinidiae via Triggering Salicylic Acid Signaling Pathway in Kiwifruit

“…Therefore, the results of this experiment may be due to the significant increase in the AcPAL gene in the kiwifruit stem after sulfur application, which is involved in lignin synthesis and significantly increases the cell wall strength, thus hindering the invasion of Psa and disease. This is similar to the results obtained in the previous studies related to the control of pear fruit diseases by calcium [61], the improvement of rice sheath blight resistance by silicon [62], and the significant reduction in the incidence of soybean wilt, Fusarium, and Aspergillus by manganese [63]. Moreover, another mechanism by highlighted bacteria could spread in the plants was through the reproduction and secretion of bacterial fluid in the xylem, thereby blocking the ducts of plants to cause the disease [57,64].…”

Quality and chemical composition of soybean seeds with different lignin contents in the pod and seed coat subjected to weathering deterioration in pre-harvest

“…According to Dantas et al (2012), there is no interference of the lignin content of the seed coat on the resistance to infection by the fungus Aspergillus flavus. Carvalho et al (2015) evaluated the effect of lignin and Mn leaf application on the incidence of fungi and found that the cultivar BRS Celeste had the lowest lignin content and was among those with the lowest incidence of Aspergillus flavus, inferring that the highest lignin content in the seed coat of soybean seeds do not result in increased resistance to infection.…”

Production, fermentation profile, and nutritional quality of silage from corn and soybean intercropping

“…No significant interaction was found between tested factors for lignin content, but soybean addition in single-row treatments (trial 1) increased such levels compared to standard corn silage (Table 3). The soybean seed coat is lignin-rich, which might have increased this polymer content in silages (CARVALHO et al, 2015), as soybean participation in ensiled mass was higher in trial 1 than was in trial 2 (Table 2).…”