Dynamics of Soil Nematode Communities Revealed Significant Variation in Greenhouse with Different Continuous Cropping Years

Abstract

22 Continuous cropping usually resulted in a series of soil problems, especially root knot nematode 23 disaster in greenhouse because of imbalance in soil nematode community. However, the dynamic 24 change in soil nematode community in greenhouse with various continuous cropping years during 25 plant growing season is unclear. Here, soil nematode communities in greenhouse after 2 and 10 26 years of continuous cropping were comparatively analyzed using 18S rDNA high-throughput 27 sequencing to reveal the changing processes in soil nematode communities. Compared to the 28 2-year greenhouse, soil in the 10-year greenhouse showed soil acidification, nutrients 29 accumulation, salinization. In term of α-diversity, Bacterial-feeding nematodes (BF) were 30 dominant in the 2-year greenhouse over the whole growing season, but plant-parasitic nematodes 31 (PP) became the dominant group in the 10-year greenhouse in the late growing season. 32 Meloidogyne gradually became the dominant group (Relative abundance 70.9%) in the 10-year 33 greenhouse, while Rhabditidae (Relative abundance from 99.8% to 26.8%) was the predominant 34 members in the 2-year greenhouse. For β-diversity, hierarchical clustering analysis, unWeighted 35 UniFrac principal component analysis (PCA) and principal co-ordinates analysis (PCoA) all 36 revealed that soil nematode communities in the two types of greenhouses exhibited significant 37 differences. Redundancy analysis (RDA) showed that soil nematode communities in the 10-year 38 greenhouse were related to high soil organic material, total nitrogen, electrical conductivity and 39 disease index of root knot nematode. Fisher' exact test and Pearson correlation coefficients 40 revealed that Meloidogyne caused main differences in soil nematode communities between the 41 two types of greenhouses. Meanwhile, population dynamics of Meloidogyne were divided into 42 dormant phase, low-level increasing phase and exponential phase during the whole season. In total, 43 the significant variation led different dynamics of soil nematode communities in the 2-year and 44 10-year greenhouse.45

Continuous Cropping Alters Multiple Biotic and Abiotic Indicators of Soil Health

“…Similarly, the β-diversity of soil nematodes also differed after the 10-year and 2-year CC. Some soil properties such as organic matter, N, and other biotic conditions also influenced the composition of soil nematodes under CC [150]. These examples suggest that CC may alter the diversity and composition of soil nematodes, while these effects may be driven by both top-down (plants and predator derived effects) and bottom-up effects under changing soil conditions.…”

“…In another study, Tian et al (2019) investigated the relative abundance of bacterial-feeding and plant-parasitic nematodes after 2 and 10 years of CC under greenhouse conditions. Regarding α-diversity, the bacterial eating nematodes were dominant in the two years across the whole growing season, whereas the plant-parasitic nematodes were dominant after 10 years in the late growing season [150]. Moreover, the meloidogyne and rhabditidae became dominant after 10-and 2-year cropping.…”

Recirculation, circular fertilizers and resilience: the potential of growing media systems for circular production

“…With the successes in insect control in horticulture, with integrated pest management (IPM) in mind, similar successes are sought after in growing media. The focus is on the control of plant pathogenic organisms such as bacteria, fungi and nematodes (Antoniou et al, 2017;Debode et al, 2018;Tian et al, 2019;Gerrewey et al, 2020). Various ideas on how to bring this about exist.…”

Literatuuronderzoek chrysantenteelt zonder stomen : Kan een monocultuur in een stabiel microbieel evenwicht blijven?

“…Een andere belangrijke factor die Meloidogyne spp infectie veroorzaakt, is het niet goed reinigen en desinfecteren van apparatuur en het verspreiden van haarden in de grond door de grondbewerkingsapparatuur. De voortdurend monocultuur van chrysanten is ook een belangrijke bijdrage aan de aanhoudende Meloidogyne spp ophoping in de bodem (Tian et. al., 2019).…”