Organic fertilizers alter the composition of pathogens and arbuscular mycorrhizal fungi in maize roots

Abstract

Roots of agricultural crops, including maize, are hosts of different microorganisms, many beneficial, like plant growth and health‐promoting arbuscular mycorrhizal fungi (AMF), as well as pathogens including Pythium, Polymyxa and Microdochium. To improve crop nutrition and health, profound knowledge is required regarding how agricultural practices affect field populations of root‐associated microorganisms. Hence, the objective of this work was to evaluate the effect of crop genotype and organic fertilizers on the plant growth performance of maize and their root‐associated microorganisms. The experiment was conducted as a fully factorial greenhouse pot experiment with maize cultivars (two land races and two hybrids) and organic fertilizers (green manure, cow manure and compost) as the two main factors. Plants were harvested 8 weeks after sowing. In general, the different maize cultivars responded similarly to the applications of the organic fertilizers. Cow manure and compost increased plant growth, whereas green manure had limited effect on plant growth. Root colonization with AMF was reduced by green manure with rape. Infection with the root pathogens Pythium and Polymyxa was reduced by all organic fertilizers, whereas in contrast, infection with Microdochium increased with the majority of the organic fertilizers applied. In conclusion, both maize genotype and organic fertilizers affect the abundance of AMF and root pathogens in maize, which should be considered when developing management strategies of these root‐inhabiting microorganisms.

Field inoculation by arbuscular mycorrhizal fungi with contrasting life-history strategies differently affects tomato nutrient uptake and residue decomposition dynamics

“…The values are consistent with the low MIP recorded in agricultural soils located in the same area (Bedini et al 2013;Di Bene et al 2013;Pellegrino et al 2011). This supports AM fungal inoculation and confirms how agricultural practices (such as type and dose of organic fertilizer; Aguilar et al 2017) can damage soil AM fungal inoculum potential and impair native AM fungal community, with putatively adverse effects on growth and yield of crops (Gosling et al 2006;Johnson 1993;Plenchette et al 2005). On the other side, the AM fungal species utilised as inocula in our study showed values of MIP similar among each other and higher than the field experimental soil.…”

Application of Manure Rather Than Plant-Origin Organic Fertilizers Alters the Fungal Community in Continuous Cropping Tobacco Soil

“…Additionally, the fungal community in the soil is tightly regulated by the nutrient contents. Previous reports indicated that the boost of fungal pathogens in the continuous cropping field was likely due to the depletion of organic C and the increase in N content, which was reversed by organic fertilization ( Aguilar et al, 2017 ). Despite these findings, the effect of organic fertilization on the fungal community in continuously cultivated tobacco soil has never been investigated to our best knowledge.…”

Effects of different organic amendments on soil pore structure acquired by three‐dimensional investigation

“…Our study reveals that under continuous cultivation, although the application of organic materials did not change the porosity of the tillage layer, it apparently adjusted the proportion of pores of various sizes in the whole pore structure, reducing the number of micropores and increasing the number of medium and large pores (Figure 3). In some studies, small pores are regarded as pores between soil aggregates and particles that facilitate water and gas migration (Glab, 2007;Wang et al, 2019), while large pores are produced by biological factors such as crop roots and earthworms Therefore, we believe that organic management measures in farmland can promote the growth of crop roots, this effect has been shown in many studies (Aguilar et al, 2017;Glab et al, 2020;Xu, Pang, et al, 2018;Zhang et al, 2020Zhang et al, , 2021.…”