Impacts of Early‐ and Late‐seral Mycorrhizae During Restoration in Seasonal Tropical Forest, Mexico

Abstract

Disturbance of vegetation and soil may change the species composition of arbuscular mycorrhizal fungi (AMF), which may in turn affect plant species responses to AMF. Seasonal tropical forest in Mexico is undergoing rapid conversion to early-successional forest because of increased wildfire and may require restoration. The responses of six early-and late-successional tree species were tested using early-and late-successional AMF inoculum. The plants were germinated in the shadehouse and received three inoculum treatments: (1) soil from a two-year-old burned site, (2) soil from a mature forest site, or (3) uninoculated controls. They were transplanted as seedlings to a site prepared by burning, and their growth was measured from September 1997 to November 2000. All six species had the greatest growth response to early-seral inoculum, but the response to late-seral inoculum varied. Two tree species, Ceiba pentandra and Guazuma ulmifolia, were smallest with late-seral inoculum, even smaller than the uninoculated plants, and the other species, Brosimum alicastrum, Havardia albicans, Acacia pennatula, and Leucaena leucocephala, had intermediate growth with late-seral inoculum. Of these, Brosimum, Havardia, and Ceiba occur in late-successional forest, and the others are early seral. Of the several growth measurements (height, cover, biomass, stem diameter), stem-diameter responses to inoculum were still significantly different into the third year for four of the species. The uninoculated plants became infected by residual inoculum in the burned experimental site within three months of transplanting, yet mycorrhizal responses persisted. The treatment size differences may be due to different species composition of the inocula. The early-seral inoculum was dominated by small-spored Glomus spp., while the late-seral inoculum had a higher density of large-spored Gigasporaceae. The latter are known from greenhouse experiments to promote a smaller plant-growth response than Glomus. Mature forest trees may withstand the carbon drain from Gigasporaceae better than establishing seedlings, so the growth patterns we observed with inoculum source are consistent with a rapidly growing successional forest, followed by slower-growing mature forest. The results suggest that early-seral AMF should be used when seedlings are inoculated for restoration, even for late-seral tree species.

Respuesta de Cedrela odorata L. a diversos inoculantes micorrízicos procedentes de dos ecosistemas tropicales

“…Además, estas fuentes pueden ser utilizadas en el futuro para la producción de plántulas con fines de reforestación o plantaciones forestales comerciales en áreas deforestadas del trópico mexicano, lo que puede propiciar una pronta recuperación de estas áreas y, por ende, una mayor adaptación, tal y como lo sugiere Allen et al (2003) en sus resultados con algunas especies tropicales.…”

“…El manejo de los HMA, integrado a la producción de plántula en vivero, es indispensable para asegurar el éxito de adaptación de las repoblaciones bajo condiciones naturales (Allen et al, 2003); por tal motivo, es importante integrar paquetes tecnológicos de diferentes especies forestales de importancia económica que se encuentran distribuidas en los tró-picos.…”

Effectiveness of native arbuscular mycorrhiza on the growth of four tree forest species from the Santa Marta Mountain, Veracruz (Mexico)

“…Studies on mycorrhizal plant dependency in rainforest have shown that most plant species are colonized by AMF (Zangaro et al, 2000;Kiers et al, 2000;Allen et al, 2003;Hernández & Salas, 2009). Poor nutrient availability in tropical soils constitutes an adequate environment for the development of AMF.…”

“…However, several authors agree on the advantages that the AMF inoculation provides on improving root growth, increasing plant survival, reducing the time plants spend in nursery, reducing cost production due to reduction of fertilizer applications, as well as increasing plant quality (Gehring & Connell, 2005;Allen et al, 2003;Hernández & Salas, 2009). Other advantages of AMF inoculation are related to the increase of photosynthetic rate during acclimatization and development of micro-propagated plants, the induction of drought resistance, and the protection of roots against pathogen attack (Ferrera-Cerrato & Alarcón, 2004;Gavito et al, 2008;Shukla et al, 2008).…”

Moving carbon between spheres, the potential oxalate-carbonate pathway of Brosimum alicastrum Sw.; Moraceae

“…The EOK analyses indicated that B. alicastrum root tissue contains a significant concentration of CaOx, which, when coupled with the Cairns et al (1997) root / shoot ratio (0.26) and Gill and Jackson (2000) root turnover rate (0.1 yr −1 ), predict that B. alicastrum deposits significant quantities of CaOx directly into its rhizosphere through the continuous decomposition and regeneration of root OM. Furthermore, investigations have demonstrated that B. alicastrum roots have strong associations with mycorrhizal fungi (Allen et al 2003;Allen et al 2005) that, Bravo et al (2013) (Table 2) even though the subjects are still very young (0.5-2 yrs). This was contrary to our hypothesis that the trees would be too young to have affected their local edaphic ecosystem; but, at the time of sampling, the Ma Rouge trees had already grown to 1.4-1.8 m in height and were producing significant quantities of CaOx, which was also detectable in the soils adjacent to them (5-25 g kg −1 ).…”