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.

This study aimed to estimate genetic parameters of Turiaçu pineapple clones using mixed models; and estimate genetic correlation coefficient between traits, to provide important information to breeding programs. For this, 19 pineapple plants were visually selected and its slips were collected and planted in a single environment and nine traits were evaluated. The genetic parameters of most evaluated traits presented significant differences between the 19 clones. Some traits, such as Fusarium wilt resistance, showed high magnitudes of heritability. Clones did not differ in relation to total titratable acidity (TTA) and total soluble solids (TSS). However, these traits, which have implications to fruit quality, showed to be negatively correlated to fruit mass (−0.46 and −0.67). The results indicate that the population of Turiaçu pineapple is suitable for selection, especially for Fusarium wilt resistance. Also, Turiaçu clones can be used in breeding programs of pineapple.

The objective of this work was to evaluate the effectiveness of seed treatment with fresh suspensions and powder formulations with Bacillus methylotrophicus to promote plant growth and induction of resistance against fusarium wilt (Fusarium oxysporum f. sp. lycopersici) in tomato plants under greenhouse conditions, verifying the occurrence of morphological and biochemical changes in the evaluated plants. Powder formulations based on Cassava (Manihot esculenta), Arrowroot (Maranta arundinacea) and sodium alginate containing Bacillus, in addition to the commercial product Quartz®, were used to microbiolize the tomato seeds of the cultivar Santa Cruz. The formulations promoted plant growth, with a seedling vigor index greater than 50% for all treatments containing B. mthylotrophicus, in addition to a significant increase in total dry matter. The treatments induced systemic resistance, controlling the fusarium wilt with a 75% reduction of the disease and activation of enzymes such as peroxidase and polyphenoloxidase, only β-1,3-glucanase presented less activity than controls (treatments without B. mthylotrophicus). Thus, the use of formulations containing Bacillus are efficient in promoting plant growth of tomato plants and in inducing resistance to the control of fusarium wilt.

The objective of the present study was to assess the anti-fungal activity of medicinal plant extracts on inhibition of Colletotrichum gloesporioides mycelial growth, sporulation and germination and on anthracnose control in Heliconia psitacorum cv. Golden Torch and Heliconia rostrata. Extracts of garlic, lemon grass, cinnamon, lemon balm, eucalyptus, ginger, mint, bitter melon and black pepper were used. The, mycelial were assessed in vitro by measuring their growth in Petri dishes. Sporulation was assessed by counting spores in a Neubauer chamber. Germination was observed based on germination tube emission. In the in vitro tests, the inflorescences were treated with the plant extracts and inoculated with the pathogen 24 h later. The results showed that all the extracts presented anti-fungal activity, in greater or lesser intensity, compared to the control. The garlic extract resulted in the highest mycelial growth inhibition rate. Regarding sporulation, the bitter melon, ginger, mint, popcorn eucalyptus and bitter melon extracts were more efficacious, interfering in spore formation; while the ginger extract most reduced spore germination inhibiting germination tube emission. For the in vivo tests, it was observed that all the plant extracts tested were efficient in reducing lesion severity in the inflorescence, showing that the use of plant extracts may be a promising alternative for managing the diseases that affect helconia post-harvest.

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