Soil abiotic factors associated with Meloidogyne spp. and Pratylenchus spp. populations in sugarcane

Abstract

Summary Meloidogyne spp. and Pratylenchus spp. are the most damaging plant-parasitic nematodes to sugarcane and the knowledge of soil characteristics that influence the occurrence of these pathogens can be useful in their management. With the objective to investigate the relationships between soil variables and populations of Meloidogyne spp. and Pratylenchus spp. in sugarcane fields, root-zone soil and root samples were collected from 20 farms located in 16 municipalities in Alagoas state, Brazil. The multivariate regression tree technique was used to model the population density’s response variables for Meloidogyne spp. and Pratylenchus spp. in the root-zone soil and the roots according to sugarcane cultivars, soil organic matter, and soil chemical and physical variables. The results showed the existence of associations between soil factors, sugarcane cultivars and populations of nematodes. Root samples from soils with K > 37.79 mmolc dm−3, Al < 5.93 mmolc dm−3 and sugarcane ‘RB92579’, ‘SP753046’, ‘SP813250’ and ‘SP921631’ showed the lowest Pratylenchus spp. population densities. However, the lowest densities in the root-zone were found in soils with sum of bases > 1.91 mmolc dm−3, Ca:Mg ratio < 1:2 and soil organic matter < 10.7 g dm−3. The lowest population densities of Meloidogyne spp. in roots were associated with sugarcane ‘RB92579’, ‘RB93509’, ‘RB98710’, ‘SP791011’ and ‘SP921631’ and soil aggregate mean diam. > 0.48 mm, while root-zone densities were minimum in soils with P > 28.59 mg dm−3. This information should support further studies to investigate the effect of each variable on populations of Pratylenchus and Meloidogyne.

Correlations Between Pratylenchus and Meloidogyne Populations, Soil Chemical Properties, Soil Texture, and Nutritional Status of Soybean Crops in Paraguay

“…The contrasting results indicate that sand content is not necessarily the determining factor for nematode prevalence and that adequate soil management may help maintain nematode population levels below the threshold of economic damage. Different from our findings, the literature has numerous reports of positive correlations between root-knot nematodes and sandy soils (Guzmán et al, 2008;Galbieri et al, 2016;Noronha et al, 2020). However, as previously mentioned, other factors might have exerted a greater effect on nematode population, mitigating the influence of soil texture.…”

“…Findings regarding organic matter and soil pH are not conclusive, with reports of negative (Leiva et al, 2020;Dias-Arieira et al, 2021) and positive correlations between Pratylenchus and organic matter (Franchini et al, 2018;Noronha et al, 2020) as well as negative (Osseni et al, 1997) and positive correlations between the nematode and soil pH (Noronha et al, 2020). Meloidogyne is consistently associated with sandy soils (Guzmán et al, 2008;Galbieri et al, 2016;Noronha et al, 2020). The species M. incognita, M. javanica, M. arenaria, and M. hapla show a negative correlation with soil organic matter (Guzmán et al, 2008).…”

“…Research suggests that nematode genus is not significantly correlated with soil pH (Guzmán et al, 2008). Furthermore, soil pH does not seem to interfere with nematode development or penetration in host roots (Melakeberhan et al, 2004), although a recent study found a positive relationship (Noronha et al, 2020).…”

“…Assessment of nutrient levels in soybean leaf tissues serves to gain insight into the crop's productive potential (Oliveira Junior et al, 2020). Previous studies investigated associations of Pratylenchus and Meloidogyne with soil physical (Galbieri et al, 2016;Noronha et al, 2020;Leiva et al, 2020;Dias-Arieira et al, 2021) and chemical properties (Guzmán, 2008;Leiva et al, 2020;Noronha et al, 2020;Dias-Arieira et al, 2021). Pratylenchus is reported to correlate positively with sandy (Leiva et al, 2020;Dias-Arieira et al, 2021) and clay sandy soils (Gallardo et al, 2015).…”

“…Pratylenchus is reported to correlate positively with sandy (Leiva et al, 2020;Dias-Arieira et al, 2021) and clay sandy soils (Gallardo et al, 2015). Findings regarding organic matter and soil pH are not conclusive, with reports of negative (Leiva et al, 2020;Dias-Arieira et al, 2021) and positive correlations between Pratylenchus and organic matter (Franchini et al, 2018;Noronha et al, 2020) as well as negative (Osseni et al, 1997) and positive correlations between the nematode and soil pH (Noronha et al, 2020). Meloidogyne is consistently associated with sandy soils (Guzmán et al, 2008;Galbieri et al, 2016;Noronha et al, 2020).…”