Influencia de las coberturas en cultivos de cítricos sobre los hongos formadores de micorrizas arbusculares en Oxisoles del piedemonte llanero colombiano

Abstract

RESUMENSe identificaron morfológicamente hongos formadores de micorrizas arbusculares nativos asociados a coberturas de gramíneas y leguminosas, establecidas en suelos Oxisoles del piedemonte llanero (Meta, Colombia) y se evaluó su capacidad de colonización. El área experimental se estableció en las calles de un cultivo de naranja Valencia donde se sembraron especies de Arachis pintoi (CIAT 18744), Brachiaria brizantha cv. Toledo, B. dictyoneura cv. Llanero, Desmodium ovalifolium cv. Maquenque, Panicum maximum (CIAT 36000), Paspalum notatum, un testigo químico (glifosato) y un testigo mecánico con guadaña. Se utilizó un diseño de bloques completos al azar con ocho tratamientos y tres repeticiones, que se evaluaron en la época húmeda y en la seca. Se tomaron muestras de suelo rizosférico y raíces de las gramíneas y leguminosas para identificar morfológicamente hongos formadores de micorrizas arbusculares y cuantificar el número de esporas y el porcentaje de colonización. Se identificaron 26 morfotipos de dichos hongos, incluyendo Scutellospora heterogama, Acaulospora scrobiculata y A. morrowiae que representaron 65% de la población presente en las dos épocas. La colonización radical osciló entre 47% y 94% con un contenido de esporas entre 63 y 300/100 g de suelo seco. Las coberturas con mayor porcentaje de colonización y diversidad de hongos formadores de micorrizas arbusculares fueron B. brizantha, B. dictyoneura y P. notatum; el control mecánico y los tratamientos con glifosato presentaron una influencia negativa sobre el contenido de esporas y colonización radical de dichos hongos.Palabras claves: biodiversidad, cítricos, morfotipos, suelo ácido, trópico bajo. ABSTRACTNative arbuscular mycorrhizal fungi associated with grass and legume cover crops established on Oxisol soils in the Colombian piedmont (Meta) were identified morphologically and the ability to colonize was evaluated. The experimental area consisted of cover crops Arachis pintoi (CIAT 18744), Brachiaria brizantha cv. Toledo, B. dictyoneura cv. Llanero, Desmodium ovalifolium cv. Maquenque, Panicum maximum (CIAT 36000), Paspalum notatum, and a chemical control (Glyphosate and mechanical control) established in the rows in a Valencia orange grove. The experiment followed a complete randomized block design (8 cover crops) and three replications, evaluated during the wet and dry seasons. Rhizosphere soil and grass and legumes roots were sampled in order to identified AMF and quantify the number of spores and the percentage of colonization. A total of 26 species were identified, including Acaulospora scrobiculata, A. morrowiae and, Scutellospora heterogama, which accounted for over 65% of the population. The percentage of root colonization ranged between 47% and 94% with spore counts between 63 and 300/100 g of dry soil. Cover crops with the highest colonization percentage and AMF diversity were B. brizantha, B. dictyoneura and P. notatum in their respective order. Glyphosate and mechanical control had a negative influence on the sporulation and coloniz...

NATIVE MICROBIOTA AND ARBUSCULAR MYCORRHIZAL FUNGI ON GROWTH OF Paspalum millegrana SCHRAD

“…The presence of vesicles in the control in the native inoculant and in the native + UFLA05 (G. albida) indicates that the colonization of P. millegrana was mainly by isolates belonging to the genus Glomus and/or Paraglomus, because this structure is unique to the Glomaceae family, which comprises these two genera and not in the genus Gigaspora (MONROY et al, 2013), as was the UFLA05 isolate.…”

“…The AMF-Paspalum interaction has been described only for P. natatu species in China (CUI et al, 2015), P. maximum and P. notatum in Colombia (MONROY et al, 2013), P. scrobiculatum in India (CHANNABASAVA; LAKSHMAN; MUTHUKUMAR, 2015) and P. dilatatum "Cousin" in Argentina (CAVAGNARO et al, 2014). However, no reports were found on the mycorrhizal interaction with P. millegrana, as well as the association of this grass with the native microbiota.…”

Soil Microfungi of the Colombian Natural Regions

“…Serralde and Ramírez [ 65 ] studied the populations of arbuscular mycorrhizal fungi associated with two corn varieties in acid soils of the piedmont llanero, during five consecutive years. In the same area, arbuscular mycorrhizal fungi associated with grass and leguminous coverages in oxisols soils were identified, and their colonization capacity was evaluated [ 66 ]. Other two studies focused on functional ligninolytic and cellulolytic fungi.…”

Diversity of arbuscular mycorrhizal fungi in the rhizosphere of saffron (Crocus sativus) plants along with age of plantation in Taliouine region in Morocco

“…Microscopic observations of spores were made in a few drops of polyvinyl-lactic acid-glycerol (PVLG) and checked at magnifications of 100x and 400x. A preliminary identification at the genus level was made based on the criteria proposed by Ferrer and Herrera (1981), Berch and Koske (1986), Schenck and Smith (1982), Hall (1987), Schenck and Perez (1987), Morton and Benny (1990), Walker et al (1982), Dalpé (1995), Pérez and Peroza (2013), Pérez et al (2012), Monroy et al (2013), Rodríguez-Morelos et al (2014, Rajeshkumar et al (2015), Błaszkowski et al (2018), and information available in different databases.…”