First report of Colletotrichum siamense causing anthracnose in Oenocarpus bacaba in Brazil.

Bacaba (Oenocarpus bacaba Mart.) is a native palm tree from Brazilian Amazon and Cerrado biomes. This tree produces a small, rounded fruit with dark skin and approximately 1.5 mm thick pulp, extensively utilized for palm heart extraction, juices, and jellies (De Cól et al. 2021). However, several diseases can adversely impact fruit yield and quality. During the 2021 growing season, anthracnose symptoms were observed in Bacaba fruits, with a disease incidence of 58% in fruits collected from the Abreulândia (9°37'15″ S, 49°9'3″ W) and Gurupi (12°25'46" S; 49°16'42" W) municipalities in Tocantins state, Brazil. A total of 198 fruits exhibiting anthracnose symptoms, characterized by deep necrotic spots, were collected. In the laboratory, symptomatic fruits had their external surfaces sterilized for 30 seconds in 70% ethanol, 1 min in 1.5% NaOCl, and then rinsed with sterile distilled water. Sterilized pieces of the fruit tissue were transferred to PDA medium and incubated for 7 days at 28 ºC with a 12 h photoperiod. After this period, two isolates were obtained from the colonies and were identified both macroscopically and microscopically as Colletotrichum sp. The colonies grown at PDA showed a white to grey cottony mycelia, with straight and fusiform conidia, ranging from 14.0 to 21.0 (mean value of 15.8 ± 1.8) µm in length and 4.0 to 7.0 (mean value of 5.5 ± 0.7) µm in width, (n = 50). For species identification, the intergenic spacer between DNA lyase, mating-type locus MAT1-2-1 (APN2/MAT-IGS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), glutamine synthetase (GS), and ß-tubulin (TUB) loci were amplified and sequenced. Resulting sequences were deposited in GenBank (OR333843, OR333844, OR333845 and OR333846). BLAST analysis of the partial APN2/MAT-IGS (99%), GAPDH (99,48%), GS (99,32%) and TUB (99,48%) sequences showed highly similarity to C. siamense isolates (IIFT223 and CBS130147). Maximum likelihood multilocus analysis placed the isolate UFTC16 within the C. siamense clade with 98% bootstrap support, clearly assigning the isolate to this species. Morphological features were consistent with the description of C. siamense (Prihastuti et al., 2009). Inoculation of Bacaba fruits and seedlings was conducted to confirm pathogenicity. The surface of uninjured Bacaba fruits was inoculated with two drops (20 µL) of conidial suspension (106 conidia mL-1). The same methodology was adopted to placed healthy leaves of 35-day-old seedlings grown in plastic tubes. Two drops of sterile distilled water were inoculated on nonwounded healthy fruits and seedlings as a negative control. The fruits and seedlings were incubated for five days in a controlled chamber at 28 °C, 70-80% humidity and a "12-h photoperiod". The experiment was conducted with five replicates (five fruits and five seedlings inoculated per isolate) and repeated once. Typical symptoms of anthracnose were observed in the fruits and leaves of Bacaba seedlings five days after inoculation. No symptoms were observed in the negative control. The pathogen was reisolated from symptomatic fruits and leaves, showing similar morphological characteristics as the original isolate, fulfilling Koch's postulates. The identification of C. siamense as the causal agent of Bacaba anthracnose helps in the diagnosis and disease control strategies of the disease. Colletotrichum siamense is a cosmopolitan species and easily found in cultivated and non-cultivated species (Batista et al. 2023). However, to the best of our knowledge, this is the first report of C. siamense causing anthracnose on Bacaba.

Genomic-proteomic analysis of a novel Bacillus thuringiensis strain: toxicity against two lepidopteran pests, abundance of Cry1Ac5 toxin, and presence of InhA1 virulence factor.

Bacillus thuringiensis (Bt) is a biological alternative to the indiscriminate use of chemical insecticides in agriculture. Due to resistance development on insect pests to Bt crops, isolating novel Bt strains is a strategy for screening new pesticidal proteins or strains containing toxin profile variety that can delay resistance. Besides, the combined genomic and proteomic approaches allow identifying pesticidal proteins and virulence factors accurately. Here, the genome of a novel Bt strain (Bt TOL651) was sequenced, and the proteins from the spore-crystal mixture were identified by proteomic analysis. Toxicity bioassays with the spore-crystal mixture against larvae of Diatraea saccharalis and Anticarsia gemmatalis, key pests of sugarcane and soybean, respectively, were performed. The toxicity of Bt TOL651 varies with the insect; A. gemmatalis (LC50 = 1.45 ng cm-2) is more susceptible than D. saccharalis (LC50 = 73.77 ng cm-2). Phylogenetic analysis of the gyrB gene indicates that TOL651 is related to Bt kenyae strains. The genomic analysis revealed the presence of cry1Aa18, cry1Ac5, cry1Ia44, and cry2Aa9 pesticidal genes. Virulence factor genes such as phospholipases (plcA, piplc), metalloproteases (inhA), hemolysins (cytK, hlyIII, hblA, hblC, hblD), and enterotoxins (nheA, nheB, nheC) were also identified. The combined use of the genomic and proteomic data indicated the expression of Cry1Aa18, Cry1Ac5, and Cry2Aa9 proteins, with Cry1Ac5 being the most abundant. InhA1 also was expressed and may contribute to Bt TOL651 pathogenicity. These results provide Bt TOL651 as a new tool for the biocontrol of lepidopteran pests.

Agronomic characterization and resistance of banana genotypes to Colletotrichum musae / Caracterização agronômica e resistência genótipos de banana a Colletotrichum Musae

Banana is the most consumed fruit in the world as it is a delicious and aromatic fruit. However, its production is limited mainly due post-harvest problems such as diseases, especially anthracnose, which accelerates senescence and causes early fall. The aim of this work was to evaluate the agronomic traits and the resistance of banana genotypes (Fhia 18, Fhia 01, Thap Mae, Caipira, Prata (control) and Maçã (control)) to the fungus Colletotrichum musae. The weight of bunch (Wb), fruit length (Fl), fruit diameter (Fd), the number of fruits per bunch (Nfc), number of hands per bunch (Nhb), yield (Yd), pH, total sugars (Brix) and finger detachment were evaluated. The AUDPC (area under the disease progress curve) showed that the genotypes Fhia 01, Maçã and Prata (15.77, 15.55 and 11.60 respectively) are more susceptible to the fungus C. musae than Caipira, Fhia 18 and Thap maeo (6.66, 7.29 and 8.76 respectively). The experiment with Fhias 18 and Thap Maeo genotypes showed lower finger detachment of 18 and 15%, and Thap maeo, Fhia18 and Caipira were resistant to C musae and presented the best agronomic characteristics.

A banana é fruta mais consumida no mundo, tradicionalmente exploradas em várias regiões do mundo, pois é uma fruta de muito saborosa e aromática. Contudo sua produção é limitada principalmente por problemas pós-colheita que mais acometem o fruto, dentre elas aparecimento de doenças principalmente a antracnose que acelera a senescência e o despencamento precoce. O objetivo desde trabalho foram avaliadas as características agronômicas e a resistência dos genótipos de banana Fhia 18, Fhia 01, Thap Mae, Caipira, Prata (controle) e Maçã (Controle), ao fungo Colletotrichum musae. A avaliação das características agronômicas como; peso do cacho (PC), comprimento dos frutos (CF), diâmetro do fruto (DF), número de frutos por cacho (NFC), número de pencas por cacho (NPC), Produtividade (Pd), pH, açúcares totais (Brix) e despencamento. A AACPD Área abaixo da curva da progressão da doença nos genótipos Fhia 01, Maçã e Prata (15,77, 15,55 e 11,60 respectivamente) mostraram se mais suscetível ao fungo C. musae que os demais genótipos Caipira, Fhia 18 e Thap maeo (6,66, 7,29 e 8,76 respectivamente), enquanto que para o experimento de despencamento genótipos Fhias 18 e Thap Maeo foram os que tiveram menor despencamento 18 e 15%, e a Os genótipos Thap maeo Fhia18 e Caipira foram resistentes a C musae e tiveram as melhores características agronômicas.

Susceptibility assessment of watermelon and pumpkin cultivars to potyvirus in Tocantins / Avaliação da susceptibilidade de cultivares de melancia e abóbora a potyvirus obtidos do estado de Tocantins

Cucurbits cultivation has great importance in the food industry. However, in the main producing regions of curcubits, the increase of cultivation areas has been limited by viral infections. Among the most prevalent viruses there is the Watermelon Mosaic Virus (WMV), Papaya Ringspot Virus (PRSV-W) and Zucchini Yellow Mosaic Virus (ZYMV). The aim of this study was to evaluate the reaction of watermelon genotypes (Crimson sweet and Charleston Gray) and pumpkin (Jacarezinho and Caserta) to isolate watermelon strains in the following cities: Palmas (PYP-12), Gurupi (PYG-14 and PYG-19), Formoso do Araguaia (PYF-6), and Porto Nacional (PyPn-36 and PyPn-39). The experiment was performed in a greenhouse, in a completely randomized design, with 5 testing plants for each repetition to measure the response of these strains to cucurbit genotypes. The inoculated strains were obtained from leaves of watermelon cv Crinson sweet with symptoms The plants were rated by severity of viral symptoms in intervals of four days during 32 days. It was verified that the cucurbit genotypes showed different susceptibility to the viral strains. However, Caserta and Charleston gray were the ones which had greater sensitivity due to their high severity variation among the tested strains. Thus, it can be observed that the reaction among strains depends on the host and this reaction can be antagonistic or synergistic, depending on the mixed infection. Charleston gray watermelon was the most susceptible to most of the viral strains. Thus, this cultivar should be avoided in these regions.

O cultivo de cucurbitáceas tem grande importância no que diz respeito à alimentação, mas o aumento das áreas de plantio tem sido limitado por infecções virais nos principais pólos produtores de cucurbitáceas. Entre os mais prevalentes destacam-se o vírus do mosaico da melancia (WMV), o vírus da mancha anelar do mamoeiro estirpe melancia (PRSV-W) e o vírus do mosaico amarelo da abobora (ZYMV). Este estudo teve como objetivo avaliar a reação dos genótipos de cucurbitácea Melancia Crimson sweet e Charleston gray; Abóbora: Jacarezinho e Caserta, para isolar variedades de safra de melancia nas cidades de Palmas (PYP-12), Gurupi (PYG-14 e PYG-19), Formoso do Araguaia (PYF-6) e Porto Nacional (PyPn-36 e PyPn-39). O experimento delineamento inteiramente casualizado (DIC), foi conduzido em estufa e foram utilizadas 5 plantas de teste para cada repetição para medir a resposta dessas cepas aos genótipos de cucurbitáceas. A inoculação dos vírus em plantas realizada a partir de folhas com a infecção de melancia Crimson sweet. As plantas inoculadas foram avaliadas por graus de severidade em quatro dias de intervalo durante 32 dias após a inoculação. Verificou-se que os genótipos de cucurbitaceas analisadas apresentaram susceptibilidade diferente às cepas virais testadas. No entanto, o genótipo de abóbora de Caserta e Charleston gray foram as que apresentou maior sensibilidade, devido à sua alta variação de severidade entre as cepas. Assim, podemos ver que a reação entre as estirpes depende do hospedeiro e a reação pode ser antagonista ou sinérgica dependendo da infecção mista. A melancia Charleston gray foi o mais suscetível à maioria das cepas virais. Assim, esta cultivar deve ser evitada nessas regiões.

Resistência à herbivoria contra Cerotoma arcuatus Olivier, 1791 (Coleoptera: Chrysomelidae) em genótipos de soja / Resistance against herbivory Cerotoma arcuatus Olivier, 1791 (Coleoptera: Chrysomelidae) in soybean genotypes

Objetivou-se neste trabalho avaliar níveis de herbivoria de Cerotoma arcuatus Olivier, 1791 (Coleoptera: Chrysomelidae) em genótipos de soja, comparando propriedades morfológicas como; densidade de tricomas (DT), espessura foliar (EF), número de C. arcuatus (NC) e área danificada (AD). O experimento foi realizado na Universidade Federal do Tocantins campo experimental de Gurupi-TO ano 2008/09, o delineamento experimental com 18 genótipos de soja EMGOPA-314, P98R91, P98Y51, MSOY-9988, P99R01, M8867RR, M9056RR, M8360RR, M8527RR, FTS-EsperançaRR, FTS-4188, C-M-015, CM-017, CM-136, CM-149, CM-102, A-7002 e MSOY-9350, semeadas em três épocas de plantio dia 03/12/08; 18/12/08; 02/01/09, cada parcela composta de três repetições, Sendo os genótipos de soja utilizados A parcela experimental foi composta por quatro linhas de 5,0 m de comprimento, com espaçamento entre linha de 0,45 m e 12 plantas m-1 linear. Foram analisados a herbivoria da C. arcuatus, quantificação da área foliar danificada (AD) em porcentagem foi utilizada um programa de imagem para quantificar as áreas danificadas pela C arcuatus. Na densidade de tricomas foi avaliada utilizando um microscópio estereoscópico e visualizados discos de 0,5 cm. A espessura foliar foi avaliada a massa seca pela área do disco. Numero de C arcuatus foi realizado utilizando um saco plástico 100x100 avaliando três batidas por parcela. Os dados foram submetidos à ANOVA e as médias comparadas pelo teste de Tukey a 5 % de probabilidade. A matriz dos genótipos versus variáveis mais a produtividade de grãos (PD) foi submetida à correlação, análise multivariada por agrupamento hierárquico e análise de componentes principais (PCA). Neste trabalho demonstrou que a densidade de tricoma foi um dos parâmetros essenciais na diminuição da herbivoria e influenciou na produtividade de grãos.

The objective of this study was to evaluate levels of herbivory Cerotoma arcuatus Olivier, 1791 (Coleoptera: Chrysomelidae) in soybean genotypes, comparing morphological properties such as; trichome density (TD), leaf thickness (EF), number of C.arcuatus (NC) and the damaged area (AD). The experiment was conducted at the Federal University of Tocantins experimental field Gurupi-TO 2008/09, the experimental design with 18 soybean genotypes EMGOPA-314, P98R91, P98Y51, MSOY-9988, P99R01, M8867RR, M9056RR, M8360RR, M8527RR, EsperançaRRFTS, FTS-4188, CM-015, CM-017, CM-136, CM-149, CM-102, A-7002- and MSOY 9350 on three sowing dates day 03/12/08; 18 / 12/08, 02/01/09, each plot consisted of three replicates Being soybean genotypes used the experimental plot consisted of four rows 5.0 m long with row spacing of 0.45 m 12 m-1 linear plants. Were analyzed herbivory of C. arcuatus, quantification of leaf area damaged (AD) in percentage was used a program image to quantify the areas damaged by C arcuatus. In trichome density was assessed using a stereoscopic microscope and viewed discs of 0.5 cm. The leaf thickness was measured dry mass by the area of the disc. Number of C arcuatus was performed using a plastic bag 100x100 evaluating three beats per plot. The data were submitted to ANOVA and means were compared by Tukey test at 5% probability. The array of genotypes versus more variable grain yield (PD) was subjected to correlation, multivariate hierarchical clustering and principal component analysis (PCA). This work demonstrated that the density of trichomes was one of the key parameters in reducing herbivory and influence on grain yield in soybean genotypes.

Toxicidade de óleos essenciais de eucalipto e citronela sobre Sitophilus zeamais Motschulsky (Coleoptera: curculionidae) / Toxicity of essential oils of eucalyptus and citronella on Sitophilus zeamais Motschulsky (Coleoptera: curculionidae)

As análises realizadas por cromatografia gasosa acoplada à espectrometria de massas CG/EM apresentou o citronelal como o principal fitoconstituinte dos óleos essenciais de Corymbia citriodora Hill & Johnson, e Cymbopogon nardus (L.), com 61,78 e 36,53%, respectivamente. A toxicidade dos óleos essenciais e do citronelal foi verificada para Sitophilus zeamais por meio das estimativas das curvas de concentrações resposta e tempos de exposição letais para 50 e 95% dos insetos (CL50, CL95, TL50 e TL95). A toxicidade do citronelal foi maior para S. zeamais, com CL50 e CL95 de 0,340 e 0,820µL/cm2 e TL50 e TL95 de 11,89 e 59,50h, respectivamente. A repelência de S. zeamais foi maior para os óleos essenciais de C. nardus e C. citriodora nas concentrações de 0,660; 0,881; 1,101 e 1,321µL/cm2 com 86,6 a 98,8%. O número de insetos emergidos dos grãos pulverizados com os óleos essenciais foi maior para o citronelal nas concentrações de 0,330; 0,440; 0,550, e 0,660µL/cm2 . A redução da massa de grãos foi menor para aqueles grãos tratados com C. citriodora e C. nardus. Óleos essenciais de C. citriodora e C. nardus podem proteger produtos armazenados pelo dano causado por S. zeamais.

Analysis of GC / MS showed citronellal as the main phytochemicals of the essential oils of Corymbia citriodora and Cymbopogon nardus, with 61.78% and 36.53%, respectively. The toxicity of essential oils and citronellal was verified for maize weevils, through the estimates of the concentration response curves and lethal exposure times, for 50% and 95% of the adults insect (LC50, LC95, LT50 and TL95). The toxicity of citronellal was higher for Sitophilus zeamais, with LC50 and LC95 of 0.340 at 0.820 µL/cm2, TL50 and TL95 of 11.89 and 59.50h, respectively. The repellency of S. zeamais was higher for the essential oils of C. nardus and C. citriodora, at concentrations of 1.321, 1.101, 0.881 and 0.660 µL/cm2, ranging from 86.6 to 98.8%. The number of insects emerged from grain sprayed with essential oils was lower for the citronellal, at concentrations of 0.330, 0.440, 0.550, and 0.660 µL/cm2. The reduction in grain weight was lower for those grains, treated with C. citriodora and C. nardus. Essential oils of E. citriodora and C. nardus can protect stored products from damage caused by S. zeamais.