Effect of different organic amendments on lettuce fusarium wilt and on selected soilborne microorganisms

Abstract

This study evaluated the effect of different organic amendments on lettuce fusarium wilt caused by Fusarium oxysporum f. sp. lactucae in pots under controlled conditions. Their effects on the density of the pathogen, on the total fungi and on fluorescent Pseudomonas spp. were also evaluated after two subsequent lettuce crops. A significant reduction in the severity of the symptoms of F. oxysporum f. sp. lactucae was found after the use of Brassica carinata pellets (52–79% reduction) and compost (49–67% reduction), while Brassica green manure and cattle and chicken manure only provided partial control of fusarium wilt. However, variations in effectiveness were observed for the same treatment in repeated trials. In general, an increase was observed in Pseudomonas and a decrease in fungal populations in the growing medium, which was obtained by mixing a blonde sphagnum peat and a sandy loam soil with B. carinata pellets and compost after two consecutive cropping cycles. Prolonging the Brassica and compost treatments from 30 to 60 days did not significantly affect disease severity, plant growth or the microbial population of the total fungi or Pseudomonas. The largest lettuce biomass was obtained in the non‐inoculated growing medium amended with brassica flour, chicken manure, B. carinata pellets and compost, as a consequence of fertilization. The treatment with B. juncea green manure, B. carinata (pellets and flour) and compost applied 30 days before planting led to promising results and merits further investigation for use under field conditions.

Influence of different biological control agents and compost on total and nitrification-driven microbial communities at rhizosphere and soil level in a lettuce -Fusarium oxysporumf. sp.lactucaepathosystem

“…; Gilardi et al . ). However, the seed transmission of this pathogen and the capacity of inoculums to survive in the soil for years, makes soil disinfection only partially effective (Garibaldi et al .…”

Effect of management of organic wastes on inactivation of Brassica nigra and Fusarium oxysporum f.sp. lactucae using soil biosolarization

“…The fungal pathogen FOL causes a disease of lettuce known as Fusarium wilt or Fusarium root rot, and affects lettuce production throughout the world . This pathogen is seed‐transmitted and now it is established in soils where lettuce is grown and causes serious economic losses . Soil solarization and SBS using dried pellets of Brassica carinata A. Braun as amendment have significantly reduced Fusarium wilt in soils .…”

Application of organic waste material overgrown with Trichoderma atroviride as a control strategy for Sclerotinia sclerotiorum and Chalara thielavioides in soil

“…Pseudomonas, Bacillus, Streptomyces is well known (Scotti et al 2015). These microorganisms increase the soil suppressiveness and often decrease the development of pathogens (Gamliel et al 2000;Gilardi et al 2016).…”