A quality substrate is essential to ensure the proper conditions for the emergence and early development of seedlings. The aim of the present study was to evaluate different proportions of termite mound substrate in the emergence and early development of tomato seedlings. The experiment was performed in a completely randomized design, with five treatments constituted by the substrates, with four replications: T 1 : Washed sand (100%); T 2 : Washed sand (75%) + termite mound material (25%); T 3 : Washed sand (50%) + termite mound material (50%); T 4 : Washed sand (25%) + termite mound material (75%) and T 5 : termite mound material (100%). The Santa Clara cultivar (tomato) of Topseed ® was used. The seeds were distributed in gerbox boxes. Emergence, emergence speed index, shoot height, number of leaves, shoot dry mass, root length and root dry mass of tomato seedlings development were evaluated after 25 days. The use of termite mound substrates is a viable alternative to the emergence and development of tomato seedlings. In general, the substrate of termite mound material (100%) was the most promising in the increment of all variables.

RESUMO-na pós-colheita do abacaxizeiro, a podridão-negra é considerada como um dos principais problemas na comercialização dos frutos. a doença é causada pelo fungo Chalara paradoxa (De Seynes) Sacc.. apesar da importância deste patógeno para a cultura, são poucas as informações relacionadas ao estudo do mesmo, com base em características fisiológicas in vitro. assim, o objetivo do trabalho foi avaliar o crescimento micelial, a esporulação e a germinação de C. paradoxa, em diferentes condições de cultivo. a partir de placas contendo colônias puras do isolado de C. paradoxa, foram retirados individualmente discos para inoculação em diferentes meios. a incubação das placas foi feita em três diferentes regimes de luminosidade e em três diferentes temperaturas. Para o crescimento micelial, esporulação e germinação, as melhores condições de cultivo in vitro de C. paradoxa foram os meios aveia (Oa) e batata (PDa) em alternância luminosa a 25°C, os meios batata (PDa) e abacaxi (PJa) no escuro contínuo, na mesma temperatura. Termos para indexaçaõ: Ananas comosus l., crescimento micelial, esporulação, germinação. BEhAVIOR IN VITRO OF ChalaRa paRadOxa, CAUSAL AGENT OF PINEAPPLE BLACk ROT IN DIFFERENT GROwTh CONDITIONSABSTRACT -in pineapple postharvest, black rot disease is considered as the main problem of fruits trade. the disease is caused by the fungus Chalara paradoxa (De Seynes) Sacc.. Despite the importance of this pathogen to pineapple, there is little information related to it, based on physiological characteristics in vitro. the objective of the study was to evaluate the mycelial growth, sporulation and germination of C. paradoxa in different growing conditions. mycelial discs were removed from pure cultures and placed for growing on petri plates containing the medias: potato-dextrose-agar (PDa), oat-agar (Oa), coconut milk-agar (Cma), and pineapple juice agar (PJa).incubation of the plates was done at three different light regimes and three different temperatures. For mycelial growth, sporulation and germination the best conditions of in vitro cultivation of C. paradoxa were Oa and PDa medias in alternating light at 25 ° C, the PDa and PJa medias in continuous darkness at the same temperature

The root lesion nematode (Pratylenchus brachyurus) is one of the main phytosanitary problems of cotton plants in Brazil. Searching for alternatives that minimize the damages in the crop, several methods are performed aiming to manage these damages. Among them, is the use of vegetal extracts. In this sense, the aim of this study was to evaluate the potential of black angico extract (Anadenanthera macrocarpa) in the management of P. brachyurus in cotton crop. The experiment was conducted in a greenhouse at the Phytopathology Laboratory of the Federal University of Piauí in Bom Jesus-PI. The experimental design was completely randomized, in a factorial scheme (2×6), composed of two sources of extracts (leaf and bark) of black angico under six concentrations (0, 20, 40, 60, 80 and 100 g L-1), with five replications per treatment. The plants were inoculated with 1900 specimen/juveniles and eggs, 96 h after the transplanting. Sixty days after the application of extracts, some agronomic variables of the cotton and P. brachyurus were evaluated. The volume and fresh root mass showed considerable gains for all concentrations with the leaf extract. The plant height was negatively influenced by concentrations above 60.83 g L-1 for both extracts. Regarding the parasitism, all the extract concentrations, regardless of the source (leaf or bark), showed suppressiveness to P. brachyurus. Therefore, the aqueous extracts of black angico present nematicidal action and favor the development of cotton plants.

Identification of resistant germplasms is crucial for crop breeding. The aim of this study was to determine the reaction of accessions of watermelon plants to Meloidogine enterolobii using two experiments. In the first experiment, 20 accessions were evaluated, and in the second, the four most promising accessions were selected in the first experiment and two controls. Both experiments were implemented under a completely randomized design with ten replications. Each parcel consisted of a plastic pot containing autoclaved soil inoculated with 2,200 eggs of M. enterolobii. Among the variables studied, the egg number and reproduction factor showed a high positive correlation. The subsamples indicated a wide variation among and within each accession (p < 0.01). At the end, variation in the response among and within the accessions was observed regarding the reproduction factor. Of the accessions evaluated, accessions 9 and 10 exhibited potential for the implementation of breeding programs.

No abstract