Evaluation of incidence and alternative control of pathogens on Cereus jamacaru DC (Cactaceae) seeds

Abstract

Cereus jamacaru, xerofilous plant used as eatable and ornamental farraginous, show higher distribution among plants in Brazilian Northeast. Considering hard studies with sanity and seeds treatment with alternative products in native species, the objective of this work was to determine pathogens incidence and control of those using essentials oils with fungistatic potential, besides the observation of the effect of those products about the germination of the seeds. Seeds of C. jamacaru (mandacaru) were collected in Areia, in the Brejo Paraibano. Pathogens incidence were evaluated by “Blotter test”, accomplished without previous disinfection of the seeds, to the ambient temperature, for seven days (control), which was compared with the seeds submitted to different concentrations of anise oil (Pimpinella anisum) and of citronela (Cymbopogon winterianus), composing the following treatments: 1% (T1), 1,5% (T2), 2,0% (T3) and 2,5% (T4).  It was used experimental design random entirely, with five treatments and ten repetitions. In the control treatment the fungus incidence: Aspergillus sp. (0,5%), Penicillium sp. (0,5%), Cladosporium sp. (13,5%), Curvularia sp. (3%), Nigrospora sp. (1%) and Rhizophus sp. (1,5%). The results showed that the growth of Cladosporium sp., Curvularia sp. and Nigrospora sp. were controlled with P. anisum oil in all the used concentrations, however, the essential oil of C. winterianus just controlled Cladosporium sp. and Nigrospora sp. Inside of the tested conditions, larger efficiency of the P. anisum oil was verified when compared with the one of C. winterianus in the control of the fungus mentioned. The essential oils products increased the germination of the seeds, when compared to the control.