Avaliação da compatibilidade de _Ricinus communis_ (Mamona) com _Fusarium Incarnatum-Equiseti_ (Complexo FIESC) e o efeito sinérgico da associação sobre _Diatraea saccharalis. _

O uso de agentes biológicos para o combate de populações de insetos em desequilíbrio está sendo amplamente difundido no Brasil. É considerada uma forma de combate eficaz, quase livre de manutenções, com preços favoráveis e aplicação simples, sem envolver, na maioria das vezes, equipamentos caros e sofisticados. Esta simplicidade, combinada à eficiência, torna os agentes biológicos excelentes opções para os agricultores e plantações, além de evitar o uso indiscriminado de agrotóxicos. O presente estudo teve como objetivo avaliar o efeito fungitóxico do extrato de folhas de mamona, (Ricinus communis L.) sobre fungos do complexo FIESC (Fusarium incarnatum-equiseti) (URM6792 e URM6798), através da análise dos parâmetros biológicos: crescimento vegetativo, esporulação e germinação de conídios, para realizar o cálculo do Índice Biológico (IB). O extrato aquoso de mamona (30%) foi adicionado ao meio de cultura Batata-Dextrose-Ágar (BDA), nas concentrações de 4, 8 e 16%. As análises foram realizadas após seis dias de inoculação e os resultados submetidos à análise estatística, através do programa Sisvar. A mortalidade de D. saccharalis foi analisada através da imersão das lagartas (2º instar) em solução contendo fungo, extrato e fungo+extrato, além do grupo controle, tratado com solução Tween 80 (0,01%). A espécie Fusarium incarnatum-equiseti URM6792 teve seu crescimento vegetativo potencializado nas concentrações de 4 e 8%. A esporulação e a germinação desta linhagem não sofreram alteração significativa com a adição do extrato, com relação ao controle. A espécie Fusarium incarnatum-equiseti URM6798 apresentou redução significante no crescimento vegetativo e esporulação, nas três concentrações quando comparadas ao controle, e sua germinação sofreu redução significativa na maior concentração, 16%. O extrato de mamona apresentou IB compatível, em todas as concentrações, com a espécie FIESC URM6792, e IB tóxico, em todas as concentrações, para FIESC URM6798. Ao final dos 12 dias, não houve diferença estatística entre os tratamentos, fungo sozinho e fungo mais extrato. Foi observada diferença estatística entre as espécies fúngicas a partir dos 9 dias de observação, com destaque para a espécie FIESC URM6798 que causou maior mortalidade de brocas (14%), quando aplicada sozinha. Os resultados obtidos sugerem respostas positivas, em futuros testes no campo e sinalizam a necessidade de mais testes para confirmar a ação sobre o inseto. 

The use of biological agents to combat unbalanced insect populations is being widespread in Brazil. It is considered an effective form of combat, almost maintenance-free, with favorable prices and simple application, without involving, in most cases, expensive and sophisticated equipment. This simplicity, combined with efficiency, make biological agents excellent options for farmers and plantations, in addition to avoiding the indiscriminate use of pesticides. The present study aimed to evaluate the fungitoxic effect of castor bean (Ricinus communis L.) leaf extract on FIESC complex (Fusarium incarnatum-equiseti) fungi (URM6792 and URM6798), through the analysis of biological parameters: vegetative growth, sporulation and conidia germination to calculate the Biological Index (BI). The castor bean extract (30%) was added to the Potato-Dextrose-Agar (BDA) culture medium at concentrations of 4,8 and 16%. The analyzes were carried out after six days of inoculation and the results were submitted to statistical analysis using the Sisvar program. Mortality of D. saccharalis was analyzed by immersing the caterpillars (2nd instar) in a solution containing fungus, extract and fungus + extract, in addition to the control group, treated with Tween 80 solution (0.01%). The species Fusarium incarnatum-equiseti URM6792 had its vegetative growth potentialized at concentrations of 4 and 8%. The sporulation and germination of this strain did not change significantly with the addition of the extract, compared to the control. The species Fusarium incarnatum-equiseti URM6798 showed a significant reduction in vegetative growth and sporulation at the three concentrations when compared to the control, and its germination was significantly reduced at the highest concentration, 16%. The castor bean extract showed compatible IB, at all concentrations, with the species FIESC URM6792, and toxic IB, at all concentrations, with FIESC URM6798. At the end of 12 days, there was no statistical difference between treatments, fungus alone and fungus plus extract. Statistical difference was observed between fungal species after 9 days of observation, with emphasis on the species FIESC URM6798, which caused higher mortality of borers (14%), when applied alone. The results obtained suggest positive responses in future field tests and signal the need for more tests to confirmree, with favorable prices and simple application, without involving, in most cases, expensive and sophisticated equipment. This simplicity, combined with efficiency, make biological agents excellent options for farmers and plantations, in addition to avoiding the indiscriminate use of pesticides. The present study aimed to evaluate the fungitoxic effect of castor bean (Ricinus communis L.) leaf extract on FIESC complex (Fusarium incarnatum-equiseti) fungi (URM6792 and URM6798), through the analysis of biological parameters: vegetative growth, sporulation and conidia germination to calculate the Biological Index (BI). The castor bean extract (30%) was added to the Potato-Dextrose-Agar (BDA) culture medium at concentrations of 4,8 and 16%. The analyzes were carried out after six days of inoculation and the results were submitted to statistical analysis using the Sisvar program. Mortality of D. saccharalis was analyzed by immersing the caterpillars (2nd instar) in a solution containing fungus, extract and fungus + extract, in addition to the control group, treated with Tween 80 solution (0.01%). The species Fusarium incarnatum-equiseti URM6792 had its vegetative growth potentialized at concentrations of 4 and 8%. The sporulation and germination of this strain did not change significantly with the addition of the extract, compared to the control. The species Fusarium incarnatum-equiseti URM6798 showed a significant reduction in vegetative growth and sporulation at the three concentrations when compared to the control, and its germination was significantly reduced at the highest concentration, 16%. The castor bean extract showed compatible IB, at all concentrations, with the species FIESC URM6792, and toxic IB, at all concentrations, with FIESC URM6798. At the end of 12 days, there was no statistical difference between treatments, fungus alone and fungus plus extract. Statistical difference was observed between fungal species after 9 days of observation, with emphasis on the species FIESC URM6798, which caused higher mortality of borers (14%), when applied alone. The results obtained suggest positive responses in future field tests and signal the need for more tests to confirm the action on the insect.