Integrated management of damping-off diseases. A review

Abstract

Damping-off is a disease that leads to the decay of germinating seeds and young seedlings, which represents for farmers one of the most important yield constraints both in nurseries and fields. As for other biotic stresses, conventional fungicides are widely used to manage this disease, with two major consequences. On the one hand, fungicide overuse threatens the human health and causes ecological concerns. On the other hand, this practice has led to the emergence of pesticide-resistant microorganisms in the environment. Thus, there are increasing concerns to develop sustainable and durable damping-off management strategies that are less reliant on conventional pesticides. Achieving such a goal requires a better knowledge of pathogen biology and disease epidemiology in order to facilitate the decision-making process. It also demands using all available non-chemical tools that can be adapted to regional and specific production situations. However, this still is not the case and major knowledge gaps must be filled. Here, we review up to 300 articles of the damping-off literature in order to highlight major knowledge gaps and identify future research priorities. The major findings are (i) damping-off is an emerging disease worldwide, which affects all agricultural and forestry crops, both in nurseries and fields; (ii) over a dozen of soil-borne fungi and fungus-like organisms are a cause of damping-off but only a few of them are frequently associated with the disease; (iii) damping-off may affect from 5 to 80% of the seedlings, thereby inducing heavy economic consequences for farmers; (iv) a lot of research efforts have been made in recent years to develop biocontrol solutions for damping-off and there are interesting future perspectives; and (v) damping-off management requires an integrated pest management (IPM) approach combining both preventive and curative tactics and strategies. Given the complex nature of damping-off and the numerous factors involved in its occurrence, we recommend further research on critical niches of complexity, such as seeds, seedbed, associated microbes and their interfaces, using novel and robust experimental and modeling approaches based on five research priorities described in this paper.

Will climate change affect sugar beet establishment of the 21st century? Insights from a simulation study using a crop emergence model

“…Secondly, sugar beet crop is often rotated with other crops including wheat, to reduce pest inocula sensu lato , although some of the crops introduced into the rotation scheme may also be affected by the same soil-borne pathogens affecting sugar beet (Motisi et al 2009). This is due to a wide host range of most soil-borne pathogens affecting the crop establishment phase (Lamichhane et al 2017). Therefore, risks related to biotic stresses may be a limiting factor to sugar beet crop establishment under two conditions: i) when seeds are not treated with conventional pesticides and when farmers plan to anticipate sowing, especially under climate change.…”

Efficiency of Marine Bacteria and Yeasts on the Biocontrol Activity of Pythium ultimum in Ancho-Type Pepper Seedlings

“…Pre-and post-emergence damping-off disease is caused by Pythium spp. in pepper; this species is economically very important worldwide [5,6]. The rapid sporangia germination of Pythium followed…”

Effects of oak root pruning in forest nurseries on potential pathogen infections

“…These pathogens cause damping-off disease in seedlings, but some are also associated with root diseases of older seedlings and trees in forest stands. Infection rates of seedlings in nurseries can range from 5% to 80%, and potentially result in substantial economic losses (Augspurger & Wilkinson, 2007;Gorzkowska, Pszczółkowska, Okorski, Nowakowska, & Oszako, 2016;Kozanitas, Osmundson, Linzer, & Garbelotto, 2017;Lamichhane et al, 2017;Montecchio, 2005;Scattolin & Montecchio, 2007;Stępniewska-Jarosz, Mańka, & Asiegbu, 2006;Stewart, Abdo, Dumroese, Klopfenstein, & Kim, 2012;Veijalainen, Lilja, & Juntunen, 2005). Weakened seedlings are more susceptible to fungal pathogens and insect pests and this initial susceptibility may remain throughout the life of the tree.…”