Assessing the impact of successive soil cultivation onMeloidogyne enterolobiiinfection and on soil bacterial assemblages

Abstract

Soil cultivation may change the soil microbiome and alter interactions between plants and parasites. The objective of this work was to evaluate temporal changes in plant health, microbiome abundance, bacterial diversity and the plant-parasitic nematode, Meloidogyne enterolobii incidence in two soil fields with different agricultural uses. Soil samples were collected from a commercial tomato production field (agricultural soil) and a single-cultivation strawberry field (native soil). Samples for the second experiment were collected from the same fields the following year. Tomato plants cv. Yearly Girl were grown in a greenhouse and inoculated with M. enterolobii. After 45 days, plants were evaluated for the plant growth parameters, nematode reproduction, and soil bacterial assemblages were assessed using cultivation-independent sequencing methods (V3/V4 region of the rRNA 16S). Overall the average of fruit fresh weight in the second experiment was 2.4-fold to 14-fold higher than the first experiment. Moreover, there was a 80.5% decrease in eggs present per root system from the first experiment to the second. The relative abundance of bacterial assemblages from Experiment 1 to Experiment 2 changed for most of the top phyla (eg. Actinobacteria, Bacteroidetes, and Chloroflexi) and genera (eg. Bacillus, Streptomyces, and Flavisolibacter) and there was no change in microbial diversity between the two experiments. This study suggests that soil management can lead to an overall decrease in nematode reproduction and better crop yield, as well as a shift in the overall bacterial assemblages.

Underground Guardians: How Collagen and Chitin Amendments Shape Soil Microbiome Structure and Function forMeloidogyne enterolobiiControl

“…These findings indicate that the efficacy of collagen and chitin in reducing nematode populations may vary depending on soil type, and therefore different soil microbiome, suggesting the indirect effect of the amendments in controlling the plant-parasitic nematode. Prior research has suggested that alterations in soil cultivation practices can impact soil suppressiveness and alter the microbial community to favor defense against M. enterolobii (Pasche et al, 2023). Thus, the soil microbes present in different soil types may differ in their use of collagen and chitin, impacting their efficacy against M. enterolobii infection.…”

“…In standard inoculation conditions, the native soil exhibited reduced metabolic activity. This difference may be due to the soil having a lower baseline metabolic activity due to inherent limitations in nutrient availability or microbial diversity due to less anthropogenic influence (Pasche et al, 2023). However, under high inoculum pressure, native soil demonstrated a notable increase in metabolic activity, suggesting a possible adaptive response to stress that aligns its metabolic profile more closely with that of agricultural soil.…”

“…Beneficial microbes have also been shown to be effective specifically in controlling infection by Meloidogyne spp. ( Microbes can lead to an antagonistic effect against nematodes, and soil amendments may be used to favor beneficial microbes over others (Pasche et al, 2023). Approximately 80% of the nematode cuticle is composed of collagen, and with addition of collagen to the soil, bacteria that produce collagenases are likely to accumulate (Page et al, 2014;Raina et al, 2019).…”

“…Beneficial microbes have also been shown to be effective specifically in controlling infection by Meloidogyne spp. (Pasche et al, 2023; Rashidifard et al, 2022; Vieira de Carvalho Júnior et al, 2022).…”

The underground world of plant disease: Rhizosphere dysbiosis reduces above‐ground plant resistance to bacterial leaf spot and alters plant transcriptome

“…The impact of soil and rhizosphere microbiome on soil‐borne diseases in plants is well‐established (Lee et al, 2021; Pasche et al, 2023), demonstrating the significant role of below‐ground microbial communities in plant health and disease resistance. However, our understanding of how these soil–root microbiome dynamics influence above‐ground diseases, particularly foliar diseases, is still underexplored (Trivedi et al, 2020).…”