Anthracnose, caused by fungi of the genus Colletotrichum, is present in the main areas where rubber trees (Hevea brasiliensis) are planted. Thus, considering that biological agents can be an alternative for disease control, the present study aimed to carry out initial studies to investigate the response of rubber tree seedlings inoculated with Colletotrichum and treated with saprobes fungi from the semiarid region of Northeast Brazil (Curvularia eragrostidis, Memnoniella levispora, Myrothecium roridum and Phialomyces macrosporus). Seedlings of the rubber tree clone RRIM600 were sprayed with biocontrol agents as preventive and curative treatments seven days before and after C. tamarilloi inoculation, respectively. Assessments included plant response to disease expression based on percentage of symptomatic area on treated leaves, percentage of graft death, and percentage of apical death in seedlings 30 days after inoculation with C. tamarilloi. In addition, the enzymes peroxidase and phenylalanine ammonia lyase (PAL) had their activity quantified by their association with plant resistance to pathogens. The fungus C. eragrostidis had the best result in controlling anthracnose when applied as a preventive treatment, showing 10% less disease than the untreated plant. The same was observed for the fungus P. macrosporus when used in the curative form. These fungi also reduced the graft death. In these cases, PAL activity was higher and may be linked to the induction of resistance against the pathogen. The peroxidase activity was not expressive for treatments with saprobic fungi in the periods studied. Therefore, among the tested fungi, C. eragrostidis and P. macrosporus are promising for the control of anthracnose, deserving further studies.

With a great concern for health and a preservation of the environment, the search for alternative sources of disease control and growth in agriculture. This is because agrochemicals are being used indiscriminately, putting human health and the environment at risk. As recent research shows which have efficient bioactive substances in the control of pathogens. For this reason, the objective of this work was to evaluate the effect of propolis extract and

There are researches with calcium to produce the cauliflower inflorescence, but for seeds production no studies were found, this element is fundamental for the fixation of the floral buds and in the production and quality of seeds. The objective was to evaluate the effect of foliar application of calcium on different phenological stages of cauliflower plants in seed production and quality. Eleven treatments were evaluated, varying the number (1 to 4) of calcium (6 g L-1 of calcium chloride) applications and the phenological stages (E1 = floral stem with 30 cm length, E2 = opening of the first flowers; E3 = formation of first siliques; E4 = 50% of silique formed), resulting: T1 = control without application of Ca; T2 = E1; T3 = E1 + E2; T4 = E1 + E2 + E3; T5 = E1 + E2 + E3 + E4; T6 = E2; T7 = E2 + E3; T8 = E2 + E3 + E4; T9 = E3; T10 = E3 + E4; T11 = E4. The results showed a higher seed production per plant in treatments T10 (E3 + E4) and T11 (E4) with 42 and 48 g per plant, and a higher number of seeds per plant, with 12,379 and 12,978, respectively, compared to the control (T1): 23 g and 5,725 seeds per plant. Calcium applications in different phenological stages did not influence the physiological quality (germination and vigor) of cauliflower seeds of cultivar 'Piracicaba Precoce'. Application of these treatments in other cultivars is promising for further studies.

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Studies on the effect of foliar fertilization on the production and quality of vegetable seeds are still scarce. There is a lack of information regarding recommendations that provide an increase in the production of seeds with high physiological potential. Thus, the objective was to evaluate the effect of boron application via leaf at different phenological stages of cauliflower on the production and phenological quality of seeds. The experiment was carried out from January 2017 to March 2018. The studied species was the cauliflower cultivar Piracicaba Precoce with 16 treatments, resulting from the combination of number of applications (1, 2, 3, 4, 5) of boron leaf pathway at 1.0 g L-¹ in five phenological stages: 30 cm floral stem; opening of the first flowers; formation of the first silicas; 50% of silica formed and 100% of silica formed, in addition to control without application of boron. The experimental design was in randomized blocks with four replications. According to the results, it was observed that the application of boron via leaf at different phenological stages of 'Piracicaba Precoce' cauliflower did not differ from the control (without boron) for seed production. Perform an application of boron via leaf to produce cauliflower seeds in the stages: opening of the first flowers (average: 96%); in the formation of the first silicas (average: 94%), and at the moment when there are 100% of silicas formed (still green) (average: 93%), there is an increase in vigor on average of 16% more when compared to plants with 30 cm of floral stem (younger stage, average: 78% vigor).