Ananas species (Bromeliaceae) are herbaceous monocotyledonous perennial tropical plants. Some of them are grown as ornamental, mainly because of their beautiful, exotic and long-lasting inflorescence and foliage. Some hybrids of Ananas comosus var. bracteatus × A. comosus var. erectifolius are being selected for use as potted plant, landscaping and even as cut flower. The objective of this study was to characterize the development of two ornamental pineapple hybrids as potted plant. Two accessions ('A' and 'D') of ornamental pineapple from the Pineapple Germplasm Bank of Embrapa Cassava & Tropical Fruits were used. The acclimatization of micropropagated plants lasted 60 days and afterwards plantlets were transferred to 1-L plastic pots containing commercial substrate. Plants were kept under protected environment (50% shading) and were fertilized monthly. Evaluations were made on the morphological plant characteristics (plant height, number of leaves and dry matter content) and response to floral induction. Accession 'A' (with predominantly purple-green leaves, green at the leaf base and apex area) had a greater development (higher leaf length, number of leaves and dry matter accumulation) compared to accession 'D' which had light green leaves. Accession 'A' had also more persistent old leaves and needed pruning. Both accessions were small-sized plants and had no spines on the leaf margins. Slow growth was noticed during the first 90 days of cultivation. The highest need for fertilization was between 90 and 150 days. Plants became responsive to floral induction at 10 months. We concluded that both accessions are suitable for pot cultivation.

During a survey in 2018 for plant nematodes associated with roots and soil in cactus cultivation areas in Ceará State (3°44'48"S, 38°34'29"W), cysts were found on roots of mandacaru, Cereus jamacaru DC. This cactus is native to Brazil, can grow to 6-10 meters in height, and is widely distributed in the Northeast region (Romeiro-Brito et al. 2016) where it is used in construction, in disease remedies, as forage, and as an ornamental (Sales et al. 2014). Several cysts, second-stage juveniles (J2) and eggs extracted from the soil and roots, using sucrose centrifugation, were examined by scanning electron microscopy (SEM) and light microscopy (LM) to determine morphological and morphometric characteristics. Molecular characteristics were determined by DNA extraction from J2 and embryonated eggs using a protocol specific for Heteroderidae (Subbotin et al., 2018). The internal transcribed spacer sequence (ITS) region of the rDNA and D2-D3 regions of the 28S rDNA were amplified using the universal primers TW81 (5′-GTTTCCGTAGGTGAACCTGC-3′) and AB28 (5′-ATATGCTTAAGTTCAGCGGGT-3′), D2A(5′-ACAAGTACCGTGAGGGAAAGTTG-3′) and D3B(5′-TCGGAAGGAACCAGCTACTA-3′), respectively. To confirm that mandacaru is a host for C. cacti, six plantlets of mandacaru were inoculated with 1,800 eggs of the nematode, and kept in a greenhouse at 31 ± 3 ºC and irrigated daily. Six non inoculated mandacaru plantlets served as control treatment. Morphometric characteristics of cysts (n=35) were body length, excluding neck, 555.8 ± 87.8 (354,9 - 727,6) μm, body width 392.1 ± 63.4 (297.9 - 553.7) μm, neck length 63.5 ± 25.8 (49.8-105.0) μm, length to width ratio 1.4 ± 0.2 (1.0-1.8) μm and vulval cone length 48.4 ± 15.2 (40.7 –53.6) μm. Cysts had a rough surface, were lemon-shaped to rounded and had a zigzag cuticular pattern with a protruding vulval cone. They were circumfenestrate without underbridge and bullae, but with the presence of vulval denticles. Measurements of second-stage juveniles (n = 13) included the body length 511.2 ± 33.7 (452.7 - 551.5) μm, stylet length 28.0 ± 2.8 (25.4 - 34.0) μm, tail length 50.7 ± 5.1 (40.6 - 57.4) μm, tail hyaline region 22.7 ± 2.2 (18.9 – 27.1), with a = 20.9 ± 2.2 (17.7-24.3) μm, b = 5.4 ± 0.4 (5.1-5.8) μm, b'= 3.4 ± 0.4 (3.1-3.9) μm, c = 10.2 ± 1.3 (8.9-13.3) μm and c' = 3.8 ± 0.4 (3.0-4.5) μm. The observations of essential morphological characteristics for identification indicated that the species found on C. jamacaru was Cactodera cacti (Filipjev & Schuurmans-Stekhoven, 1941) Krall & Krall, 1978. The sequences of the studied rDNA regions were submitted to GenBank (ITS: MW562829 and D2–D3 regions of 28S: MW562830). The samples used for molecular analysis showed a high degree of sequence identity (99.59%) with C. cacti, from China, Iran and USA for the ITS region. The identity of the D2-D3 regions of 28S sequence was 99.54% with C. cacti isolates from Germany and 99.41% with isolates from USA. Phylogenetic analyses were performed using Maximum likelihood (ML) method for both individual loci, confirming the species as Cactodera cacti. All inoculated mandacaru plantlets showed C. cacti cysts on the roots after 60 days, confirming that mandacaru is a host for C. cacti. This species was reported in São Paulo State, in 2001, associated with ornamental cactus cultivated in pots, but plant species were not identified (Santos et al., 2001). The second report in Brazil was to Schlumbergera sp., an ornamental plant (Oliveira et al. 2007). In both studies, the nematode was not morphologically nor molecularly characterized. Cactodera cacti has been commonly associated with cactus worldwide (Esser, 1992). It has been reported in association with C. jamacaru was first reported in 2011 in China (Duan et al. 2012). This is the first report of the occurrence of C. cacti on C. jamacaru in field conditions in Brazil, and its presence in cactus cultivation areas with agricultural importance represents a threat to cactus production in the country.

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Cowpea, Vigna unguiculata (L.) Walp, is a very important Fabaceae in the diet of families in the northeast region of Brazil. This plant species is among the different cultures affected by the root-knot nematode. In this region, in addition to phytonematodes, another condition that affects cowpea productivity is salinity, one of the main abiotic limiting factors. The cultivar Pitiúba, however, has good adaptability to salt stress conditions. However, information on the behavior of root-knot nematodes in an environment with high levels of salinity for this crop is still scarce. Based on the above, the objective of this work was: 1) to evaluate the hatchability of J2 of Meloidogyne enterolobii in 100mM NaCl solution; 2) evaluate the motility and infectivity of J2 of M. enterolobii in saline solution at the levels of 0, 25, 50, 75, 100, 125, 150, 175, 200, 300, and 400mM; 3) to investigate the impairment of the development of M. enterolobii in cowpea Pitiúba under irrigation with NaCl solution at 100mM. It was found that J2 hatching, motility, and infectivity of juveniles of M. enterolobii were not affected by the levels of salinity tested in vitro. In Pitiúba, irrigation with 100 mM saline solution considerably affected the development of juveniles of the pathogen in the roots.