ACTINOBACTERIA AND ORGANIC FERTILIZERS FOR MANAGEMENT OF THE NEMATODE Scutellonema bradys IN YAM PLANTS

Abstract

This study aimed to evaluate the in vitro nematicidal effect of metabolites produced by actinobacteria strains, aqueous extracts from fresh and dry biomass of leguminous plants (sunn hemp, pigeon pea and Gliricidia sepium), liquid residue from sisal (Agave sisalana Perrine ex Engelm) and cassava (Manihot esculenta) to control Scutellonema bradys. Strains of actinobacteria and leguminous plants (sunn hemp, pigeon pea and gliricidia) were evaluated against S. bradys in yam plants. Strains AC-92, AC-12, AC-50 and AC-52 showed nematicidal effect against S. bradys under in vitro conditions. The aqueous extracts from the fresh biomass of sunn hemp, gliricidia and pigeon pea are more efficient than the aqueous extracts of the dry biomass of these plants for control of S. bradys under in vitro conditions. The liquid residues from sisal and cassava, in concentrations above 20 %, also have nematicidal effect against S. bradys under in vitro conditions. The green manures (sunn hemp, pigeon pea and gliricídia) and actinobacteria strains, singly or in combination, are effective for the management of S. bradys in yam crop.

Hunting Bioactive Molecules from the Agave Genus: An Update on Extraction and Biological Potential

“…Conversely, fermented juice caused the inhibition of beneficial soil organisms. Likewise, Dos Santos Fernandes et al [104] confirmed the nematicide activity of the liquid agro-waste of A. sisalana Perrine (20% v/v) against Scutellomena bradys with a 100% mortality rate after 24 h.…”

Síntesis de nuevos antifúngicos de origen natural para su uso en agricultura

“…S. spororaveus CKS2, S. microflavus CKS6 and S. fulvissimus CKS 7). P r e -p r i n t In sustainable agriculture, the potential of Streptomyces to produce antibiotics and other secondary metabolites can be used to control phytopathogenic fungi and bacteria (Schrey and Tarkka 2008) and even to act as nematicidals (Santos et al 2016). Moreover, the use of Streptomyces as agro-antibiotics (Demain 2009) and as biocontrol agents against numerous fungal and viral pathogens is becoming increasingly popular and is reaching the commercialization stage in many countries ( Trejo-Estrada et al 1998 A selection of very promising Streptomyces spp.…”

“…Lytic enzymes such as chitinase and lipase that bacteria from the Streptomyces genus produce (Santos et al 2016) allowed their use as biocontrol agents against nematodes (Scutellonema bradys in yam plants). The production of chitinase enzymes caused the destruction of the nematode cuticle, in which chitin is an important constituent .…”