Almond Anthracnose: Current Knowledge and Future Perspectives

Almond anthracnose caused by Colletotrichum spp. has been described as one of the most important diseases of this nut crop in the main almond-growing regions worldwide, including California, Australia and Spain. Currently, almond anthracnose is considered a re-emerging disease in the countries across the Mediterranean Basin due to the shift of plantations from the original crop areas to others with climatic, edaphic and orographic conditions favoring crop growing and yield. The pathogen mainly affects fruit at the youngest maturity stages, causing depressed, round and orange or brown lesions with abundant gum. The affected fruits can fall prematurely and lead to the drying of branches, causing significant economic losses in years of epidemics. This review aims to compile the current knowledge on the etiology, epidemiology and management of this disease

Inoculum and infection dynamics of Polystigma amygdalinum in almond orchards in Spain

Red leaf blotch (RLB) disease of almond, caused by Polystigma amygdalinum, is an important foliar disease in most production regions of the Mediterranean basin and the Middle East because severe infections may cause a premature defoliation of the tree. Some key aspects on the epidemiology of P. amygdalinum were studied in multiyear trials in two almond-growing regions in Spain, which included the seasonal development of perithecia and production and germination of ascospores along with the disease incubation and plant infectivity periods. Our results showed that primary inoculum was available in extended periods (January to August). Significant differences in ascospore amounts among regions, higher in the southern Andalusia and lower in the northern Catalonia, and years of study were detected. The factors geographical location, sampling period, and evaluation year were found significant on the development of P. amygdalinum perithecia. Variable ascospore germination rates were observed from April to July: >15% but rarely exceeding 30%. The RLB infectivity period in Catalonia extended from March to mid-June, whereas in Andalusia it was from March to May. The incubation period was mainly in a range of 5 to 10 weeks in Catalonia. The environmental conditions of October to January influence the available ascospore amounts in the next season. RLB infection occurs in spring to summer when mean temperatures are in the range 10 to 20°C. These results represent the first step in developing a prediction model of the disease that might serve as a tool for the control of RLB.info:eu-repo/semantics/acceptedVersio

Evaluation of Phenolic Profile and Antioxidant Activity of Eleven Pistachio Cultivars (Pistacia vera L.) Cultivated in Andalusia

Pistachio (Pistacia vera L.) is a nut with a good adaptability to the Mediterranean conditions of cultivation, specifically in the Andalusian region, becoming an emerging crop. Moreover, it has been getting attention in the past years for the great content of bioactive compounds such as polyphenols. Although some studies have reported the polyphenolic profile of pistachios, most of them have analyzed the hull part, considered as a residue, and not the kernel which is the edible part. Therefore, characterization of eleven varieties of pistachios kernels cultivated in Andalusia and harvested in 2019 and 2020 was carried out by UHPLC-MS (ultra-high-performance liquid chromatography high-resolution mass spectrometry). The identification and quantification of 56 polyphenolic compounds was performed, being the hydroxybenzoic acids group the most abundant with a 71–86% of the total amount followed by flavan-3-ols group that accounted for 8–24%. Moreover, 3,4-dihydroxybenzoic acid was the main compound in most of the varieties, followed by vanillic acid hexoside. Larnaka, Avdat, Aegina, and Mateur presented the highest amount of total polyphenols, while Kalehghouchi, Joley, Lost Hills, Kerman, and Golden Hills were the varieties with the lowest content. Regarding the harvest season, no significant differences (p < 0.01) were found in the total amount of polyphenols between 2019 and 2020. In addition, the antioxidant activity was measured by DPPH (1,1-diphenyl-2-picryl-hydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), and ORAC (oxygen radical absorbance capacity) assays, showing a similar trend as that of the polyphenols

Distribución y diagnóstico de nematodos fitoparásitos en especies frutales de hueso en España

Trabajo presentado en el XVI Congreso Nacional Ciencias Hortícolas, celebrado en Córdoba (España) del 17 al 22 de octubre de 2021.Los patrones de las especies frutales de hueso, especies del género Prunus e híbridos entre ellas, constituyen una herramienta fundamental para el cultivo en condiciones edáficas o climáticas adversas y la presencia de agentes fitopatógenos residentes en el suelo. Entre estos últimos, los nematodos fitoparásitos son en la actualidad un factor limitante para el desarrollo de estos cultivos, y en especial, algunas especies de nematodos noduladores de raíces (Meloidogyne spp.) así como lesionadores de raíces (Pratylenchus spp.). Algunos de los patrones de Prunus más utilizados son inmunes y/o resistentes a la presencia de algunas especies de nematodos noduladores de las raíces. Sin embargo, la presencia de especies de Meloidogyne a las que no presentan resistencia o la presencia de altos niveles de otros nematodos fitoparásitos pueden suponer un elevado riesgo para el establecimiento y mantenimiento de plantaciones rentables. En este trabajo se han prospectado las principales zonas productoras de especies frutales de hueso en España, incluyendo los valles del Guadalquivir, Ebro y Júcar-Segura. El diagnóstico nematológico reveló la presencia de las principales especies de nematodos noduladores tales como M. incognita, M. javanica y M. arenaria. Además, se ha confirmado la presencia de Pratylenchus vulnus y P. penetrans, ambos patogénicos en plantaciones de Prunus. Asimismo, se han detectado elevados niveles de otros nematodos fitoparásitos como Criconemoides xenoplax, Helicotylenchus digonicus, H. microlobus, Paratylenchus hamatus, P. tenuicaudatus y Xiphinema pachtaicum .Proyecto RTI2018-095925-A-I00 del Ministerio de Ciencia, Innovación y Universidade