Epidemiology of Fusarium agave wilt in Agave tequilana Weber var. azul

Abstract

Ramírez-Ramírez M.J., Mancilla-Margalli N.A., Meza-Álvarez L., Turincio-Tadeo R., Guzmán-de Pena D., AvilaMiranda M.E. (2017) Fusarium oxysporum is reported as the principal causal agent limiting production of Agave tequilana Weber var. azul, but frequent isolation of F. solani, and symptoms typical of F. solani as a pathogen like severe reddish coloured root rot and loss of soil anchorage are frequently associated with diseased agaves. Inoculations of agave plantlets with F. solani induced typical agave root rot symptoms in greenhouse trials. The incidence of both pathogens was determined molecularly with specific primers in the ITS2 sequence. Dispersion patterns of agave wilt, determined in plantations of different age, indicated a tendency to produce aggregated patterns over time as the disease spread from the initial symptomatic plant to adjacent plants. Although both fungi were isolated from agave diseased plants, and in spite of the higher percentage of detection and root rot symptoms, it is concluded that F. solani may have a greater impact in agave wilt.

Genomic analysis unveils reduced genetic variability but increased proportion of heterozygotic genotypes of the intensively managed mezcal agave, Agave angustifolia

“…In the short term, the production of mezcal benefits from the control over genetic variability and homogeneous phenotypes that vegetative propagation offers. Nevertheless, clonal propagation has also discouraged the breeding of new varieties and may increase the susceptibility of the cultivated plants to different diseases and pests, as previously noted in agaves (Fucikovsky, 2001; Dalton, 2005; Ramírez‐Ramírez et al, 2017; Rubio‐Ríos et al, 2019).…”

Spatial and temporal dynamics of blue agave (Agavetequilana Weber var. azul) wilt in Jalisco Mexico

“…With the increase in the cultivated area, due to the greater world demand for tequila, wilting has increased its importance, particularly in the warmer zones of the TDO (Flores-López, Chávez-Durán, Mora-Orozco, & C, Rodríguez-Moreno VM., 2016). Agave wilt is attributed mainly to Fusarium oxysporum, although the occurrence of Fusarium solani has also been reported (Ávila-Miranda et al, 2010;Ramírez-Ramírez et al, 2017).…”

“…Little is known about the spatial dynamics of blue agave wilt (Ávila-Miranda et al, 2010;Ramírez-Ramírez et al, 2017). Apparently, no reports have been published in the international literature about its temporal dynamics.…”

“…Agave wilt severity class 2. d Agave wilt severity class 3. e Total wilt incidence. As time passes, they form aggregates of diseased plants due to the transmission from plant to plant and to the occurrence of primary infections; however, contagion from plant to plant by Fusarium spp., it is generally slow(Raaijmakers et al, 2009;Ramírez-Ramírez et al, 2017). It can be modulated by changes in the soil moisture regime(CRT, 2005), by the increase or decrease in temperature…”

BACTERIAL DIVERSITY WITH PLANT GROWTH-PROMOTING POTENTIAL ISOLATED FROM Agave americana RHIZOSPHERE

“…Local farmers have established plantations of A. americana to obtain sufficient raw materials for agroindustrial use. However, the water and soil nutrient scarcity, and some diseases caused by fungi, primarily Fusarium species (Ramírez-Ramírez et al, 2017), limit plant growth, consequently, plants reach maturity only after 5 to 7 years instead of instead of a few years. An alternative for obtaining mature plants for industrial use is the application of plant growth-promoting bacteria, but it is necessary to assess the possible effects of PGPB on A. americana to increase the survival and growth of plantlets.…”