Ceratocystis wilt on cultivars mango trees exposed to water deficit

A mangueira (Mangifera indica) é uma frutífera de importância comercial no Brasil e no mundo. É cultivada em diversas regiões, incluindo o semiárido e árido irrigados, tais como no Vale do São Francisco, no Brasil, e países como Omã e Paquistão. Nesses locais o déficit hídrico é considerado um dos principais fatores que limitam o desenvolvimento vegetal. Além disso, a murcha-de-ceratocystis, causada por Ceratocystis fimbriata, é uma das principais doenças da mangicultura do Brasil e em Omã e Paquistão. Não há fungicidas eficientes, sendo o método de controle mais eficiente é o uso de variedades resistentes. Levanta-se a hipótese de que o déficit hídrico possa causar da predisposição de infecção de C. fimbriata em variedades de mangueira resistentes. No entanto, até o momento não há estudos sobre a interação entre C. fimbriata e mangueiras submetidas a déficit hídrico. O objetivo deste estudo foi avaliar o efeito do déficit hídrico na incidência e severidade da doença em variedades de mangueiras consideradas resistente à C. fimbriata. Para isso, três variedades de mangueira, „Ubá‟, „Dura‟ e „Manila‟, foram avaliadas quanto à resistência em diferentes condições de déficit hídrico. As mudas de mangueira conduzidas em vaso com substrato comercial a base de pinus foram submetidas a quatro níveis de déficit hídrico e inoculadas com C. fimbriata (CEBS15). Plantas não inoculadas e submetidas aos mesmos regimes hídricos serviram de testemunha. As mudas das variedades „Ubá‟ e „Dura‟ foram conduzidas na mesma época, enquanto que „Manila‟ foi conduzida posteriormente. Cada vaso contendo uma planta foi considerado como uma unidade experimental. Os vasos foram preenchidos com a mesma quantidade (6,8 kg) de substrato. Avaliou-se a mortalidade de mudas mortas, número médio de dias da inoculação até a morte das plantas; potencial hídrico foliar (Ψw), diâmetro de caule (DC), comprimentos das lesões no sentido longitudinal ao caule, área da lesão no sentido radial do caule, severidades das lesões nos sentidos longitudinal e radial, trocas gasosas e na „Manila‟ também se avaliou a fluorescência da clorofila a. Os resultados foram submetidos à análise estatística descritiva. Não houve morte de plantas não inoculadas. A mortalidade foi baixa na „Ubá‟ e alta na „Dura‟, mesmo em condições consideradas sem déficit hídrico. Já na „Manila‟ a viii mortalidade foi alta em déficit hídrico severo apresentando o maior número de dias entre a inoculação e morte. De forma geral, a „Ubá‟ apresentou os menores valores de severidade e comprimento de lesão, sendo que o déficit hídrico influenciou no aumento da lesão. A „Dura‟ apresentou maior severidade e comprimento de lesão, não influenciados pelo nível de déficit hídrico. A „Manila‟ apresentou a maior severidade e o maior comprimento de lesão em 15% da Cp. Houve redução do Ψw e DC das plantas que morreram. As trocas gasosas foram comprometidas nas plantas inoculadas, principalmente nas plantas mantidas sob déficit hídrico severo. Os valores das variáveis de fluorescência da clorofila a apresentaram reduções severas em plantas da variedade „Manila‟ inoculadas e mantidas a 15% da Cp. Concluiu-se que a variedade „Ubá‟ permaneceu resistente, mesmo em condições de déficit hídrico; a „Dura‟ não foi resistente ao isolado CEBS15, mesmo em condições ótimas de irrigação; e a „Manila‟ foi suscetível em condições de déficit hídrico severo.The mango tree (Mangifera indica) is a fruitful of commercial importance in Brazil and worldwide. It is cultivated in several regions, including the semi-arid and arid irrigated, as São Francisco Valley in Brazil, and countries like Pakistan and Oman. In these places the water deficit is considered one of the main factors that limit plant growth. Moreover, Ceratocystis wilt, caused by Ceratocystis fimbriata, is a major disease of mango in Brazil and Oman and Pakistan. There are no effective fungicides, and then the most efficient method of control is the use of resistant varieties. Raises the hypothesis that water deficit may cause predisposition to infection of C. fimbriata on varieties of mango trees resistant. However, until now there are no studies on the interaction between C. fimbriata and mango trees exposed to water deficit. The aim of this study was to evaluate the effect of drought on the incidence and severity of disease in mango varieties considered resistant C. fimbriata. For this, three varieties of mango, 'Ubá', 'Dura' and 'Manila', were evaluated for resistance in different conditions of water deficit. Seedlings potted mango conducted with commercial substrate base pine were treated with four levels of water deficit and inoculated with C. fimbriata (CEBS15). Plants not inoculated and subjected to the same water regimes served as witness. The seedlings of the varieties 'Ubá' and 'Dura' were conducted at the same time, while 'Manila' was conducted later. Each pot contains a plant and was regarded as an experimental unit. The pots were filled with the same amount (6.8 kg) of substrate. Were evaluated the mortality, average number of days from inoculation to death of plants, leaf water potential (Ψw), trunk diameter (DC), lengths of lesions in the longitudinal direction to the stem, the lesion area in the radial direction of the stem, severity of lesions in longitudinal and radial directions, gas exchange and in the 'Manila' also evaluating the fluorescence of chlorophyll a. The results were submitted to descriptive statistical analysis. No deaths of non-inoculated plants. The mortality was low in 'Ubá' and high in 'Dura', even in conditions considered without water deficit. In the 'Manila' mortality was high in severe water deficit presenting the highest number of days between inoculation and death. In general, the 'Ubá' showed the lowest values of severity and lesion length, and water deficit influenced the increase in lesion size. x The 'Dura' showed greater severity and length of lesion and were not influenced by the level of water deficit. The 'Manila' had the highest severity and lesion length at 15% of Cp. Decreased in the Ψw and DC of plants that died. Gas exchanges were compromised in the inoculated plants, especially in plants grown under severe drought. The parameters of chlorophyll a fluorescence showed severe reductions in inoculated plants of the variety 'Manila' and maintained at 15% of Cp. It was concluded that the variety 'Ubá' remained resilient, even in conditions of water deficit; the 'Dura' was not resistant to the isolated CEBS15, even under optimal irrigation conditions; and the 'Manila' was susceptible in severe water deficit conditions

CERATOCYSTIS WILT IN ‘UBÁ’ AND ‘DURA’ MANGO TREES UNDER WATER DEFICIT

<div><p>ABSTRACT The occurrence of water stress in mango trees grown in orchards located in semi-arid climates in Brazil is frequent. Water stress caused to plants may predispose them to the incidence of fungal diseases. The aim of this study was to evaluate the effect of water deficit on the incidence and severity of Ceratocystis wilt in mango trees considered resistant. Seedlings of ‘Ubá’ and ‘Dura’ were kept in pots and submitted to different water stress levels and inoculated with Ceratocystis fimbriata isolate (CEBS15). Mortality was low in ‘Ubá’ plants and high in ‘Dura’ plants. ‘Ubá’ plants showed lower severity and lesion length. In ‘Ubá’ plants, water deficit influenced the increase in lesion length. ‘Dura’ plants showed greater severity and lesion length, which were not affected by increasing water stress. It was concluded that ‘Ubá’ variety is resistant to fungus Ceratocystis fimbriata, even in severe drought conditions, while ‘Dura’ variety was not resistant to CEBS15 isolate, even under optimum irrigation conditions.</p></div

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data