Effect of Compost Particle Size on Suppression of Plant Diseases

Abstract

Predictability of compost-induced suppression of soil-borne plant diseases is poor. Part of the variability in disease suppression could be due to the heterogeneity of a given compost. Therefore, the disease suppressive properties of different wet-sieved fractions of two composts against three soil-borne plant pathogens were studied. The ability of a green waste and a yard waste compost to suppress the soil-borne plant pathogens Fusarium oxysporum f.sp. lini (host: flax), Phytophthora cinnamomi (host: lupin), and Meloidogyne hapla (host: tomato) was determined. The following compost fractions were prepared: 2-4 mm (40% v/v with peat-based substrate), 1-2 mm (35 or 45% v/v; comparable number of particles and comparable organic matter content as the 2-4 mm fraction amendment respectively), and 1-2 mm (35% v/v) obtained from the 2-4 mm fraction by a series of dry-sieving, crushing, and wet-sieving. The 2-4 mm compost fraction of both composts showed significantly higher disease suppression for the three pathosystems, except for P. cinnamomi with one compost, in which there was no effect. For both composts, oxygen uptake rate showed a significant positive correlation with disease suppression of all pathogens except for P. cinnamomi. For the composts studied, substrate quality as expressed by oxygen uptake rate, seems to be of greater importance for disease suppression than compost particle size per se.

Bioconversion of waste paper into soil conditioner and its effect on plants growth and microbial population of the soil

“…Micrococcus sp and Pseudomonas sp have been reported as soil bacteria [18,19,22,23].The results obtained also showed that the presence of these pathogens in the soil could in turn affect the soil fertility by reducing plant nutrient uptake which in turn will affect plant growth. The increase in the microbial population with time agrees with the work of Lozana et al, [24] who reported that changes in microbial activity and community structure after compost application can lead to the increased of soil -borne plant pathogens. The presence of these fungal isolates in the soil samples was not a surprise as there are all soil fungi [25].…”

Organic amendments and their influences on plant-parasitic and free-living nematodes: a promising method for nematode management?

“…Interestingly, adding more of the same amendment did not necessarily induce better results (e.g., Lozano et al, 2009). Different kinds of compost (e.g., made from animal manures, garden or household wastes, or other waste products) were the most common form of organic amendments investigated (26 studies).…”

Pudrición basal causada por Phytophthora capcisi en plantas de chile tratadas con vermicompost

“…El grado de supresión que se ha observado es muchas veces impredecible y varía de acuerdo a factores como el tipo de biomasa de origen, el proceso de compostaje, la estabilidad del producto, el tipo de aplicación y la dosis empleada (Hoitink et al, 2006;Rijn et al, 2007;Lozano et al, 2009;Artavia et al, 2010). Al respecto, Bonanomi et al (2010) al analizar 1964 experimentos observaron supresión en el 45% de los casos, ningún efecto en el 35% e incremento en la incidencia de la enfermedad en el 20% restante.…”