terclim by ICS banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2023 9 Preplant fumigation only temporarily reduces Northern root-knot nematode

Preplant fumigation only temporarily reduces Northern root-knot nematode


Context and purpose of the study – Management of plant-parasitic nematodes is typically focused on preplant fumigation, especially in a vineyard replant scenario. While the data are clear that this practice reduces nematodes immediately after application, which is useful in annually-cropped systems, does it have staying power in perennial cropping systems? The northern root-knot nematode Meloidogyne hapla reduces the overall lifespan and productivity of vineyards, but it does so over a long time period (slow, chronic decline). In two different commercial own-rooted V. vinifera vineyards, both undergoing vineyard replanting, we explored whether preplant fumigation reduced M. hapla densities in soils immediately after application. At one of these locations, we have explored the long-term effect of fumigation by monitoring the site for seven years post fumigation.

Material and methods – This trial was conducted at two commercial vineyards in eastern Washington State (USA). Both sites were previously planted to own-rooted V. vinifera, and were being replanted (in part) to own-rooted V. vinifera. Vineyard 1Old vines were removed in fall 2018, and the site was fumigated with 1,3-dichloropropene (1, 3-D) soil injection in spring 2019; nonfumigated areas were also included in the trial. The site was replanted in August 2019. Vineyard 2 – Older vines were treated with foliar glyphosate, and the soil fumigated with drip-applied metam sodium in fall 2014; nonfumigated areas were also included in the trial. Vines were removed over the winter, and the site was replanted in spring 2015. At both locations, soil samples for M. hapla enumeration were collected prior to fumigation, and every spring and fall post-fumigation. Nematode densities and nematode dosage were used to evaluate the effects of fumigation on subsequent nematode development on own-rooted V. vinifera vines.

Results – The fumigation with either 1,3-D or metam sodium had varying levels of efficacy at reducing M. hapla densities within 6 months of treatment (p = 0.31 Vineyard 1; p = 0.04 Vineyard 2) relative to non-fumigated plots. At both locations, in fumigated plots, total M. hapla densities reached preplant fumigation levels in own-rooted vines within 18 months post-fumigation (p = 0.94, Vineyard 1; p = 0.10 Vineyard 2). In Vineyard 2, after 7 years post-fumigation, there was no difference in nematode densities between fumigated and non-fumigated plots, and own-rooted vines showed equivalent levels of decline relative to vines planted on nematode-tolerant rootstocks that were also included in these trials. These results suggest that preplant fumigation alone is not a long-term control option for the management of M. hapla, and the adoption of resistant or tolerant rootstocks, along with other cultural control methods, will be needed for successful vineyard replanting.


Publication date: June 22, 2023

Issue: GiESCO 2023

Type: Article


Michelle M. MOYER*1, Maria MIRELES1, Bernadette GAGNIER1, Katherine E. EAST2, and Inga A. ZASADA3

1WSU Prosser IAREC, 24106 North Bunn Road, Prosser, WA, 99350, USA
2USDA-Horticultural Crops Production and Genetic Improvement Research Unit, 24106 North Bunn Road, Prosser, WA 99350, USA
3USDA-Horticultural Crops Disease and Pest Management Research Unit, 3420 NW Orchard Ave, Corvallis, OR 97330, USA

Contact the author*


rootknot nematode, fumigation, rootstocks, own-rooted, integrated pest management


GiESCO | GIESCO 2023 | IVES Conference Series


Related articles…


Climate change has brought several impacts that are becoming increasingly intense during the last few years and put at risk the quality of the berries or even the plant’s sustainability. Such extreme climatic events impact the composition of the wine while modulating its quality and the consumer preferences (Tempère et al., 2019). The three most important changes that take place in the must are: 1) decrease acidity, 2) increase of the concentration of sugar, hence increase of alcohol in the wine, and 3) modification
of the sensory balance and the development for example of cooked fruit aromas.


In Italy, in the past two decades, the rate of temperature increases (0.0369 °C per year) was slightly higher compared to the world average (0.0313 °C per year). It has also been indicated that the number and intensity of heat waves have increased considerably in the last decades. (IEA, 2022). Viticultural zones can be classified with climatic indexes. Huglin’s index (HI) considers the temperature in a definite area and has been considered as reliable to evaluate the thermal suitability for winegrape production (Zhang et al., 2023).

A synthesis approach on the impact of elevated CO2 on berry physiology and yield of Vitis vinifera

Besides the increase in global mean temperature the second main challenge of a changing climate is the increase in atmospheric carbon dioxide (CO2) in relation to physiology and yield performance of grapevines. The benefits of increasing CO2 levels under greenhouse environment or open field studies have been well investigated for various annual crops. Research under free carbon dioxide enrichment on field-grown perennial plants such as grapevines is limited to a few studies. Further, chamber and greenhouse experiments have been conducted mostly on potted vines under eCO2 conditions.

Microbial ecosystems in wineries – molecular interactions between species and modelling of population dynamics

Microbial ecosystems are primary drivers of viticultural, oenological and other cellar-related processes
such as wastewater treatment. Metagenomic datasets have broadly mapped the vast microbial species
diversity of many of the relevant ecological niches within the broader wine environment, from vineyard
soils to plants and grapes to fermentation. The data highlight that species identities and diversity
significantly impact agronomic performance of vineyards as well as wine quality, but the complexity
of these systems and of microbial growth dynamics has defeated attempts to offer actionable
tools to guide or predict specific outcomes of ecosystem-based interventions.

Searching for the sweet spot: a focus on wine dealcoholization

It is well known that the vinification of grapes at full maturation can produce rich, full-bodied wines,
with intense and complex flavour profiles. However, the juice obtained from such grapes may have very
high sugar concentration, resulting in wines with an excessive concentration of ethanol. In addition, the decoupling between technological maturity and phenolic/aromatic one due to global warming, exacerbates this problem in some wine-growing regions. In parallel with the increase of the mean alcohol content of wines on the market, also the demand for reduced alcohol beverages has increased in recent years, mainly as a result of health and social concerns about the risks related to the consumption of alcohol.