Sanity of rice seed, biocontrol, characterization and transmission of Curvularia lunata on rice seed-seedlingsThis study evaluates the sanitary quality of rice seeds cultivar Bonança, quantifies the transmission of Curvularia lunata associated with seeds -seedling and evaluates the efficiency of Bacillus spp. isolates for the control of leaf spot. The samples were disinfected and plated, and seed health was evaluated after seven days. After confirmation of pathogenicity, the seedlings inoculated by the spraying method and the occurrence of disease was assessed after seven days. For characterization of the C. lunata isolate, width and length measurements and number of septa of 100 conidia were taken. We assessed transmission rate of C. lunata in 12 trays, each with 100 seeds, and conducted evaluations at 7, 14, 21 days after infection. From each of the 100 seedlings we separated the primary root, the stem and glumes and plated them on PDA for evaluation after seven days. The inoculation of Bacillus isolates was carried out throughaerial spraying of the suspension on the plants. After one week, C. lunata was inoculated and after 15 days

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RESUMOPalavras-chave adicionais: adubação verde, controle alternativo, Fusarium oxysporum f. sp. lycopersici.A utilização de materiais orgânicos que melhoram as características físicas, químicas e biológicas do solo vem sendo estudada como indutor da supressividade a fitopatógenos. Objetivou -se ava lia r o efeito da incorporação da parte aérea de leguminosas no controle da fu sariose do toma teiro. Os resídu os frescos da s legu minosas leu cena, feijã o gua ndu, amendoim forrageiro e feijã o de porco fora m incorpora dos a o solo nas concentrações 0 ; 2 0 ; 4 0 ; 6 0 e 80 g L -1 . Sementes de tomateiro da varieda de Sa nta Cru z Ka da Giga nte fora m semea da s em bandeja s contendo terra a u toclava do e húmu s de minhoca . As muda s foram tra nspla nta da s para va sos, contendo su bstra to (terra a utoclava da + resíduo fresco), 1 5 dia s a pós a semeadura . Aos 1 5 di a s a pós o t ra n sp la nti o re a li zo u -se a ino cu la çã o , po r m ei o de ferimento de ra ízes em meia lua , aplica ndo em seguida 2 0 mL da Cruz, S.M.C.; Rodrigues, A.A.C.; Candido e Silva, E.K.; Oliveira, L.J.M.G. Supressividade por incorporação de resíduo de leguminosas no controle da fusariose do tomateiro. Summa Phytopathologica, v.39, n.3, p.180-185, 2013. su sp e n sã o d e 1 x1 0 6 c on í d i o s m L -1 p o r p l a nt a . A a v a l ia ç ã o fo i re a liz a da 2 1 dia s a pós a i noc u la ç ã o a tr a vés de esc a la de not a s varia ndo de 1 a 5. O delineamento experimenta l foi inteira mente casua liza do, com qu atro repetições, sendo a u nida de experimenta l d u a s p l a nt a s po r v a so . A i n c o r po r a ç ã o d a pa r t e a é r e a d a s leguminosas leucena, feijão guandu, amendoim forrageiro e feijão de porco demonstrou eficiência no controle da fu sa riose. Ma ior percentu a l de controle foi obtido com os resídu os de a mendoim forrageiro (40 g L -1 ), feijão de porco (60 g L -1 ) e leucena (80 g L -1 ), a presenta ndo u m percentu a l de controle de 7 3 ,3 %. O a mendoim forra geiro pode ser considerado o ma is eficiente, por necessitar de uma menor concentração para atingir o mesmo percentual de controle da fusariose.Os fitopatógenos habitantes do solo são de difícil controle, pois podem sobreviver por anos no solo de áreas cultivadas por meio de estruturas de resistência como clamidósporos de Fusarium oxysporum, fazendo-se necessário a adoção de medidas de manejo integrado de doenças (3, 15). Dentre as medidas de manejo integrado para o controle de patógenos habitantes do solo, a incorporação de matéria orgânica é uma alternativa viável, (29), visto que pode ajudar a equilibrar a sua microfauna, aumentando seu potencial de controle de doenças.T he u se of orga nic materia ls that improve physica l, chemica l a n d b i o l og i c a l so i l p r o p er t i e s h a s be e n st u d i e d a s in d u c e r o f suppressiveness to pla nt pathogens. This study aimed to eva lu ate t h e e ffec t o f i n c o rp o r a ti n g le g u m e sh o ot i n th e c on t r o l o f Fu sa rium wilt affecting toma toes. Fresh residu...

Resumo -O objetivo deste trabalho foi avaliar o efeito de indutores de resistência abióticos no controle da fusariose (Fusarium guttiforme) do abacaxizeiro na fase pré-colheita, em área de ocorrência natural da doença, e verificar se promoveram alterações físico-químicas e bioquímicas nos frutos. Os produtos testados foram fosfito de potássio, fosfito de cálcio, fosfito de cobre, Agro-Mos, silicato de cálcio, Biopirol e Bion pulverizados em campo, nas dosagens recomendadas pelos fabricantes. Fosfito de potássio, Biopirol e fosfito de cobre foram os mais eficientes na redução da incidência da fusariose do abacaxizeiro em campo, com 91,67, 70,01 e 67,68% de controle, respectivamente. As análises físico-químicas mostraram que os tratamentos não promoveram alteração no pH, nos sólidos solúveis totais e na acidez total dos frutos, enquanto, nas análises bioquímicas, apenas a β-1,3-glucanase apresentou menor atividade em relação à testemunha (água destilada esterilizada), com exceção do tratamento com fosfito de potássio. Assim, a adubação foliar com fosfito de potássio e fosfito de cobre, assim como o tratamento com o Biopirol, podem auxiliar no controle da fusariose do abacaxi.Termos para indexação: Fusarium guttiforme, Agro-Mos, Bion, fosfitos, silicato. Abiotic resistance inducers for control of pineapple fusariosisAbstract -The objective of this work was to evaluate the effect of abiotic resistance inducers on the control of pineapple fusariosis (Fusarium guttiforme) in the pre-harvest period, in an area with natural occurrence of the disease in the field, and to check for any physicochemical and biochemical changes in the fruits. The products tested were potassium phosphite, calcium phosphite, copper phosphite, Agro-Mos, calcium silicate, Biopirol, and Bion sprayed on the field, at the dosages recommended by the manufacturers. Potassium phosphite, Biopirol, and copper phosphite were the most effective in reducing the incidence of pineapple fusariosis in the field, with 91.67%, 70.01%, and 67.68% of control, respectively. The physicochemical analyses showed that the treatments did not promote change in pH, total soluble solids, and total acidity of fruits, while, in biochemical analyses, only β-1,3-glucanase showed lower expression compared with the control (sterilized distilled water), except for the treatment with potassium phosphite. Therefore, foliar fertilization with potassium phosphite and copper phosphite, as well as the treatment with Biopirol, may aid in the control of pineapple fusariosis.

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Papaya target-spot, caused by fungus Corynespora cassiicola presents a wide geographic distribution, causing leaf spots in several hosts. The aim of this research was to evaluate the behavior of papaya varieties and/or selections to the natural occurrence of target spot, and test the fungi toxic effect of neem, citronella and eucalyptus extracts, and fungi static effects of Bacillus isolates on the fungus C. cassiicola in vitro. To evaluate the natural occurrence of the disease in field, symptoms on leaves of 11 papaya varieties and/or selections have been assessed. The pathogenicity of isolates was verified by inoculation of plants in greenhouse. Neem, citronella and eucalyptus extracts were prepared at concentrations of 10, 15 and 20% and poured into Petri dishes containing C. cassiicola mycelium discs. For , Bacillusnine isolates were used, and the antagonistic potential was evaluated by the pairing of pathogen and isolate colonies by the circle method. Papaya varieties and/or selections presented all leaves with injury, and Canaan Sunrise Solo and Canaan Golden selections showed the greatest number of injuries per leaf, showing that papaya varieties and/or selections respond differently to the phytopathogen. All plant extracts tested showed inhibitory effect on the mycelial growth of C. cassiicola in vitro. Bacillus isolates showed an antagonistic potential on the mycelial growth of the fungus, with B. methylotrophicus (Iso 31 and Iso 41) being the most promising as a biological control agent. The results indicate that forms of alternative control of diseases are promising in the management of papaya target-spot.

The objective of the present study was to assess the seed health quality, quantification of seed-seedling pathogen transmission and the effect of plant extracts in reducing plant pathogens in the seeds of the tomato varieties San Marzano and Ipa 6. For the seed health, the samples were disinfested, plated and assessed after seven days, according to the Brazilian Seed Analysis Rule. For the transmission rate, 12 trays were prepared with 100 seeds each and assessed at 7, 14 and 21 d.a.s. (days after seeding) using 100 seedlings. The plant (main root, stalk and leaves) tissues were plated in PDA culture medium and assessed after seven days of incubation. Aqueous extracts were prepared from cinnamon, basil, neem and eucalyptus with 0.5% concentration and the seeds were immersed in each solution for 10 minutes. Then, they plated and assessed after seven days. The health test showed that biggest incidences of Aspergillus fumigatus (26 %) and Aspergillus flavus (26 %) were occurred in the seeds of the varieties Ipa 6 and San Marzano, respectively. The fungi A. flavus, A. fumigatus, A. niger, R. stolonifer and Curvularia sp. were detected in quantification of transmission in the seeds of the two tomato varieties. The treatment with basil extract resulted in the least fungus incidence in the transmission quantification of ‘San Marzano’ tomato seeds, while on Ipa 6 seeds the eucalyptus treatment performed better. The interference of treatments was not observed in tomato seed germination. However, there was decrease in incident of pathogens in seeds treated with the plant extracts and different effects was observed based on type and species of the pathogen.

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