6 research outputs found
Nodulation, arbuscular mycorrhizal colonization and growth of some legumes native from Brazil
Nodulation, arbuscular mycorrhizal colonization and growth of some legumes native from Brazil
The effects of rhizobial and mycorrhizal inoculation, nitrogen and phosphorus fertilization on nodulation, mycorrhizal colonization and initial growth were examined in Brazilian native plants, Enterolobium contortisiliquum (Vell. Conc.) Morong, Inga laurina (Sw.) Willd., Lonchocarpus muehlbergianus Hassl and Platypodium elegans Vogel. The experiment was carried out in a glasshouse using plastic bags filled with a mixture of sandy soil from riparian forest and vermiculite (2:1) amended with basal nutrients including NP, P and N and infected with rhizobia (r), mycorrhiza (m) or both (rm), amounting seven treatments: NP, P, P+r, P+rm, N, N+m and N+rm, with ten replications each. The plants were analyzed at 120 and 255 days after sowing. P deficiency negatively affected growth and nodulation of all species. Autochton arbuscular mycorrhizal fungi (AMF) colonized host roots and fungal inoculations did not enhance mycorrhizal colonization, which was also favored by added P. Nodulation was relatively higher in E. contortisiliquum and L. muehlbergianus, mainly in treatments containing P, and with rhizobial inoculation (P+r). Plants from these treatments developed better than others and, despite the rhizobia inoculated had no synergistic relationship with inoculated AMF, they also showed the best percentages of mycorrhizal colonization. Moreover, these two species showed highest rates of acetylene reduction and highest leghemoglobin content. These results suggest that E. contortisiliquum and L. muehlbergianus can have advantages for establishment in soils with low nitrogen levels
High-resolution melting analysis for testing the authenticity of fresh and canned heart of palm, an economically important non-timber forest product from the Neotropics
Analysis of the arabidopsis REM gene family predicts functions during flower development
Photosynthetic and metabolic acclimation to repeated drought events play key roles in drought tolerance in coffee
Over the last decades, most information on the mechanisms underlying tolerance to drought has been gained by
considering this stress as a single event that happens just once in the life of a plant, in contrast to what occurs under
natural conditions where recurrent drought episodes are the rule. Here we explored mechanisms of drought toler-
ance in coffee (Coffea canephora) plants from a broader perspective, integrating key aspects of plant physiology and
biochemistry. We show that plants exposed to multiple drought events displayed higher photosynthetic rates, which
were largely accounted for by biochemical rather than diffusive or hydraulic factors, than those submitted to drought
for the first time. Indeed, these plants displayed higher activities of RuBisCO and other enzymes associated with car-
bon and antioxidant metabolism. Acclimation to multiple drought events involved the expression of trainable genes
related to drought tolerance and was also associated with a deep metabolite reprogramming with concordant altera-
tions in central metabolic processes such as respiration and photorespiration. Our results demonstrate that plants
exposed to multiple drought cycles can develop a differential acclimation that potentiates their defence mechanisms,
allowing them to be kept in an ‘alert state’ to successfully cope with further drought events