No abstract

In the present study, the following was investigated: (a) The effect of ulvan on in vivo and in vitro biocontrol of Debaryomyces hansenii and Stenotrophomonas rhizophila against Fusarium proliferaum and (b) the effect of ulvan on in vivo and in vitro growth of D. hansenii and S. rhizophila and muskmelon quality parameters. The results showed that the biocontrol activity of D. hansenii and S. rhizophila could be enhanced by ulvan (5 g/L). The combination of ulvan and S. rhizophila resulted in a more effective control of fruit rot in comparison to fungicide benomyl. On in vitro growth of F. proliferatum, individual treatments of D. hansenii and S. rhizophila inhibited spore germination and mycelial growth with no statistical difference with the combined treatments. Ulvan does not have a direct effect on the in vivo and in vitro growth of D. hansenii and S. rhizophila. Furthermore, the combined treatments improve the natural disease incidence and quality parameters like weight, firmness, total soluble solids (TSS), and pH. These results suggest that the use of ulvan may be an effective method to improve the biological activity of D. hansenii and S. rhizophila.

Postharvest diseases of fruits caused by phytopathogens cause losses up to 50% of global production. Phytopathogens control is performed with synthetic fungicides, but the application causes environmental contamination problems and human and animal health in addition to generating resistance. Yeasts are antagonist microorganisms that have been used in the last years as biocontrol agents and in sustainable postharvest disease management in fruits. Yeast application for biocontrol of phytopathogens has been an effective action worldwide. This review explores the sustainable use of yeasts in each continent, the main antagonistic mechanisms towards phytopathogens, their relationship with OMIC sciences, and patents at the world level that involve yeast-based-products for their biocontrol.

Since the introduction of glyphosate (N-(phosphomethyl) glycine) in 1974, it has been the most used nonselective and broad-spectrum herbicide around the world. The widespread use of glyphosate and glyphosate-based herbicides is due to their low-cost efficiency in killing weeds, their rapid absorption by plants, and the general mistaken perception of their low toxicity to the environment and living organisms. As a consequence of the intensive use and accumulation of glyphosate and its derivatives on environmental sources, major concerns about the harmful side effects of glyphosate and its metabolites on human, plant, and animal health, and for water and soil quality, are emerging. Glyphosate can reach water bodies by soil leaching, runoff, and sometimes by the direct application of some approved formulations. Moreover, glyphosate can reach nontarget plants by different mechanisms, such as spray application, release through the tissue of treated plants, and dead tissue from weeds. As a consequence of this nontarget exposure, glyphosate residues are being detected in the food chains of diverse products, such as bread, cereal products, wheat, vegetable oil, fruit juice, beer, wine, honey, eggs, and others. The World Health Organization reclassified glyphosate as probably carcinogenic to humans in 2015 by the IARC. Thus, many review articles concerning different glyphosate-related aspects have been published recently. The risks, disagreements, and concerns regarding glyphosate usage have led to a general controversy about whether glyphosate should be banned, restricted, or promoted. Thus, this review article makes an overview of the basis for scientists, regulatory agencies, and the public in general, with consideration to the facts on and recommendations for the future of glyphosate usage.

Se estima que en el futuro la producción mundial de cacao (Theobroma cacao L.) será insuficiente para su demanda, debido a factores como: pérdida por plagas y enfermedades, árboles envejecidos, rendimientos limitados y efectos del cambio climático. El bioestimulante Quitomax®, cuyo ingrediente bioactivo principal es el quitosano, es un inductor de crecimiento y resistencia, y un antimicrobiano con resultados promisorios en cultivos agrícolas. Sin embargo, debido a que no se ha investigado su efecto sobre el enraizamiento, establecimiento y crecimiento de cacao, el objetivo de este trabajo fue evaluar el efecto del Quitomax® sobre dos variedades comerciales de cacao, en comparación con el producto comercial Raizyner GNS. El diseño experimental fue un arreglo factorial con los dos clones de cacao (A) y tres concentraciones de quitosano (100, 500 y 1000 mg L-1) (B) con tres repeticiones por tratamiento. Como controles se utilizaron plantas no tratadas y plantas tratadas con Raizyner GNS (5000 mg L-1). El bioestimulante Quitomax® promovió un aumento significativo de las variables de crecimiento vegetativo evaluadas de los clones de cacao en comparación con los controles. En relación con la regeneración de las plantas, Quitomax® disminuyó entre un 18% y un 50% los niveles de los esquejes no enraizados. Además, el Quitomax®, favoreció la promoción de crecimiento y bioestimulación de plantas de cacao durante la reproducción clonal por esquejes con resultados incluso mejores que los de algunos otros productos comerciales como Raizyner GNS.