First Report of Colletotrichum tropicale Causing Anthracnose on Pitaya (Hylocereus costaricensis) in Brazil.

Pitaya, Hylocereus costaricensis, is a species of the Cactaceae family and originated in the Americas (Ortiz & Livera, 1995). It has been cultivated in Brazil and has shown a great potential for fruit production and is currently present in several markets (Faleiro et al. 2021). In July 2018, infected plants of pitaya with symptoms of anthracnose were obtained from an orchard in Fortaleza, Ceará Brazil, (3°44'24.5"S 38°34'30.8"W), with 50% disease incidence. The symptoms observed consisted of well-defined and depressed stains, that initially appeared as reddish-orange spots and were surrounded by a border of dark-brown color. As the lesion progressed, the center became light brown or whitish in color, with black dots appearing later. Four cladodes were collected with anthracnose symptoms. The pathogen was isolated from symptomatic cladodes, which were surface disinfected with 1% v/v NaClO and 70% v/v ethanol, rinsed with sterile distilled water, transferred onto potato dextrose agar (PDA) medium and incubated under a light/dark (12h/12h) photoperiod. Two isolates were recovered from the lesions on cladodes. Pure cultures were obtained from single conidia produced on colonies grown on PDA medium, using an inoculation needle under a microscope. Colonies on PDA exhibited white aerial mycelia with an orange conidial mass. The colonies were light grey in the front and light orange in the reverse of the plate. Morphological features suggested that the isolates had the same characteristics as previously described for Colletotrichum spp. (Weir et al., 2012). In order to identify the species of the isolates, the genomic DNA of UFCM 0684 and UFCM 0685 isolates was extracted using the CTAB method and the ITS region, TUB2, ACT, GS, GAPDH gene fragments were amplified. PCR products were sequenced and the resulting sequences were submitted to phylogenetic analyses based on maximum likelihood for the combination of the genes. The isolates grouped within Colletotrichum tropicale with 99% bootstrap support. The sequences obtained in this study were deposited in GenBank as ACT (accession no. OL799311, OL799312), TUB2 (OL799313; OL799314), GAPDH (OL799315, OL799316), GS (OL799317; OL799318) and ITS (OL799319; OL799320). After that, the UFCM 0685 isolate was selected to study for further characterization. Conidia (n = 50) were 13.7 (length) × 4.7 µm (width) in average, hyaline, aseptate and cylindrical. To complete Koch's postulates, pathogenicity tests were performed in moist chamber for one week at 25°C with 80% relative humidity on a 12 h fluorescent light/dark photoperiod. The cladodes were wounded using a sterilized needle and inoculated with 10 µl of a conidial suspension (1 × 106 conidia/ml) on three cladodes with five wounds each. The same number of uninoculated cladode was used as control. The experiment was performed twice. Two weeks later, all inoculated cladodes showed necrotic symptoms, which were similar to the symptoms previously observed in the field. The uninoculated cladode remained symptomless. The fungus was reisolated from the inoculated cladode and its morphological characteristics were similar to the original isolate. Colletotrichum tropicale has been reported to cause anthracnose on H. costaricensis in Mexico (Nunez-Garcia et al. 2023), H. undatus, H. monocanthus and H. megalanthus (Evallo et al. 2022). For the best of our knowledge, this is the first report of anthracnose caused by C. tropicale in H. costaricensis in Brazil.

First report of stem gray blight on Hylocereus megalanthus and Hylocereus polyrhizus caused by Diaporthe arecae in Brazil.

In November 2021, stem gray blight symptoms were seen on two dragon fruit (pitaya) species (Hylocereus megalanthus and H. polyrhizus) in an orchard with 100% disease incidence in Fortaleza, Ceará, Brazil (3°44'24.5"S 38°34'30.8"W). The symptoms were initially yellowish to dark brown lesions, and as the symptoms progressed, the lesions turned grayish with small black pycnidia in the center. Isolation was carried out by disinfecting small pieces of the symptomatic stems in 70% ethanol for 1 min, followed by 1% NaOCl for 1 min, and then rinsed three times with sterile distilled water. Excess water was removed using sterile filter paper. Then the stem fragments were placed on PDA media. Colonies produced small black pycnidia with conidia and some were sterile after 68 days of incubation. Two monosporic isolates were obtained from the colonies: UFCM 0708 from H. megalanthus and the UFCM 0710 from H. polyrhizus, which were used for pathogenicity test, morphological and molecular identification. The colony on PDA was smoke gray with aerial mycelium and the reverse was smoke grey to dark grey. The α-conidia from UFCM 0708 and UFCM 0710 were hyaline, aseptate and fusiform and measured 6.4 to 9.7 (8.0) x 1.2 to 2.4 (1.7) µm and 6 to 13.1 (8.2) x 1.7 to 2.4 (2.0) µm, respectively. The ß-conidia from UFCM 0708 and UFCM 0710 were hyaline, aseptate and filiform and measured 15 to 22.5 (18.8) x 0.6 to 1.7 (1.0) µm, and 17.2 to 27.5 (22.3) x 0.5 to 1.0 (0.8) µm (n=30), respectively. This morphology placed the isolates as Diaporthe sp. (Udayanga et al. 2012). For further confirmation, genomic DNA was extracted from the isolates (UFCM 0708 and UFCM 0710), and beta-tubulin (TUB2) and translation elongation factor 1-alpha (TEF1) gene fragments were amplified. BLASTn search results with isolates TEF1 and TUB2 sequences varied from 98.58% to 99.52% identity to the ex-type sequence of Diaporthe arecae (CBS 161.64). Phylogenetic analysis of concatenated sequences alignment carried out using the Maxinum-likelihood and Bayesian Inference analysis placed the isolates within D. arecae clade with 86% bootstrap and 0.99 posterior probabilities support. The sequences obtained in this study were deposited in GenBank (TEF1: OP534720 and OP534722; TUB2: OP534717 and OP534719). The isolates were confirmed as D. arecae based on molecular analysis and morphological characteristics (Gomes et al. 2013). Koch's postulates were completed as described by Karim et al. (2019) through the inoculation of six stems of each dragon fruit (pitaya) species. The stems were wounded by removing a 5 mm diameter disc and after that they were inoculated with a 5 mm diameter mycelial plug from 5 days old PDA plates. PDA plugs were used as control. Each stem was covered with a plastic bag and sterilized water was added into the sterilized filter paper to maintain humidity. The bags were kept in a room at day and night temperature of 25 ± 2 °C. The same symptoms seen in the field appeared on the stems 21 days after inoculation. The control stems remained symptomless. Diaporthe arecae have been reported on H. polyrhizus in Malaysia (Huda-Shakirah et al. 2021). To our knowledge, this is the first report of D. arecae on H. megalanthus and H. polyrhizus in Brazil.

Balance design for robust foliar nutrient diagnosis of "Prata" banana (Musa spp.).

The "Cavendish" and "Prata" subgroups represent respectively 47% and 24% of the world banana production. Compared to world average progressing from 10.6 to 20.6 t ha-1 between 1961 and 2016, and despite sustained domestic demand and the introduction of new cultivars, banana yield in Brazil has stagnated around 14.5 t ha-1 mainly due to nutrient and water mismanagement. "Prata" is now the dominant subgroup in N-E Brazil and is fertigated at high costs. Nutrient balances computed as isometric log-ratios (ilr) provide a comprehensive understanding of nutrient relationships in the diagnostic leaf at high yield level by combining raw concentration data. Although the most appropriate method for multivariate analysis of compositional balances may be less efficient due to non-normal data distribution and limited nutrient mobility in the plant, robustness of the nutrient balance approach could be improved using Box-Cox exponents assigned to raw foliar concentrations. Our objective was to evaluate the accuracy of nutrient balances to diagnose fertigated "Prata" orchards. The dataset comprised 609 observations on fruit yields and leaf tissue compositions collected from 2010 to 2016 in Ceará state, N-E Brazil. Raw nutrient concentration ranges were ineffective as diagnostic tool due to considerable overlapping of concentration ranges for low- and high-yielding subpopulations at cutoff yield of 40 Mg ha-1. Nutrient concentrations were combined into isometric log-ratios (ilr) and normalized by Box-Cox corrections between 0 and 1 which may also account for restricted nutrient transfer from leaf to fruit. Despite reduced ilr skewness, Box-Cox coefficients did not improve model robustness measured as the accuracy of the Cate-Nelson partition between yield and the multivariate distance across ilr values. Sensitivity was 94%, indicating that low yields are attributable primarily to nutrient imbalance. There were 148 false-positive specimens (high yield despite nutrient imbalance) likely due to suboptimal nutrition, contamination, or luxury consumption. The profitability of "Prata" orchards could be enhanced by rebalancing nutrients using ilr standards with no need for Box-Cox correction.

Seleção de clones de cajueiro comum pelo método em "tandem" e índice de classificação / Selection of common cashew clones by tandem method and rank index

Com o objetivo de selecionar clones de cajueiro comum e avaliar a eficiência da metodologia do índice da soma de classificação no melhoramento da cultura foi instalado, em 1999, um experimento em área de produtor, no município de Beberibe, CE, no delineamento de blocos ao acaso com 40 clones, três repetições e cinco plantas por parcela, no espaçamento de 10 m x 10 m. Os clones foram avaliados, durante cinco anos, para altura de planta (m) e diâmetro da copa (m). A avaliação da produção de castanha (kg/planta/safra) foi feita em três safras. A maior produtividade de castanha foi para o clone Comum 30, com 885 kg.ha-1 e 1.117 kg.ha-1, respectivamente na primeira e segunda safra, enquanto que o clone Comum 21 se destacou no terceiro ano de produção com 1.299 kg.ha-1. Pela avaliação conjunta do porte das plantas, produção de castanha, performance fenotípica do clone e características tecnológicas da amêndoa, os clones Comum 18, Comum 21, Comum 28, Comum 30, Comum 31 e Comum 36 foram selecionados para teste em larga escala. A seleção de clones de cajueiro comum através do índice da soma de classificação revelou-se inapropriada quando comparada ao método em "tandem".

The objective of this work was to select clones of common cashew and to evaluate the efficiency of the rank index in the cashew improvement. The trial was set up in May 1999 using a randomized complete block design with 40 clones, 3 replications and 5 plants per plot, spaced in 10m x 10m. Plant height (m) and canopy diameter (m) were measured for five years. Nut yield control (kg/plant/year) was done for three years. The Common clone 30 showed the largest nut yield, 885 kg.ha-1 and 1.117 kg.ha-1 for the first and second year of evaluation, respectively. Considering the caracteristics plant vigour, nut yield and kernel quality used together as reference of population average, the clones Common 18, Common 21, Common 28, Common 30, Common 31 and Common 36 were selected as the most promising for test in wide scale and local commercial plantation. The selection of common cashew clones by rank index was inefficient in relation to the "tandem" method.

Liming and postharvest quality of carambola fruits

Tendo como objetivo avaliar os efeitos da aplicação de doses crescentes de calcário ao solo, na qualidade de frutos de caramboleira pela avaliação das alterações físico-químicas dos frutos após a colheita, foi instalado um experimento em Bebedouro-SP,Brasil, sobre um Latossolo Vermelho distrófico, ácido. Os tratamentos foram doses crescentes de calcário, em pré-plantio, como segue: D0 = zero; D1 = metade da dose; D2 = a dose; D3 = 1,5 vez a dose; e D4 = 2 vezes a dose para elevar V= 70%. No florescimento da caramboleira, avaliou-se o teor de cálcio na folha. Após a colheita dos frutos, determinou-se o teor de cálcio na polpa, o peso dos frutos, diâmetro transversal, comprimento, peso da polpa, % de polpa, ºBrix, acidez titulável e Ratio dos frutos. Diariamente, durante sete dias de armazenamento em condições ambiente, determinou-se a perda de massa fresca e a firmeza dos frutos. A calagem proporcionou um aumentou linear de cálcio nas folhas e nos frutos da caramboleira. A nutrição adequada da planta com cálcio melhorou a qualidade dos frutos pós-colheita, permitindo um período de armazenamento mais longo ( 2 days), em condições ambiente.