Arbuscular mycorrhiza fungi increased the susceptibility ofAstragalus adsurgensto powdery mildew caused byErysiphe pisi

Abstract

Powdery mildew caused by Erysiphe pisi is a major factor that affects the growth of standing milkvetch (Astragalus adsurgens). As arbuscular mycorrhizal fungi (AMF) have shown to be enhancing the resistance of plants to biotrophic pathogens such as powdery mildew, a study was carried out to look at the effects of three AMF, either singularly or in combination, on the growth of standing milkvetch and susceptibility to E. pisi. The results showed that the presence of AMF enhanced the growth of standing milkvetch even though their presence in the roots increased susceptibility to this foliage pathogen compared with plants having no AMF. This increase in growth of plants with severe infection of powdery mildew was especially surprising as leaves contained lower levels of chlorophyll than plants without AMF and had a greater concentration of malondialdehyde, an indicator of the damage of cell membrane. The effects on the extent of growth and powdery mildew enhancement differed inconsistently with the type of AMF in roots. The effects on growth and powdery mildew were not related to intensity of AMF colonisation. The peroxidase (POD) was consistently higher activity (15% to 72%) in plants with AMF than plants without them.

The Mycorrizal Status in Vineyards Affected by Esca

“…In addition, some research pointed out a higher protector effect of F. mosseae in comparison to other AMF species [ 61 , 62 ]. However, some studies reported higher severity of symptoms caused by viruses [ 35 , 63 ] or fungi disease [ 64 ], on leaves of mycorrhizal plants compared to non-mycorrhizal control plants.…”

War and Peas: Molecular Bases of Resistance to Powdery Mildew in Pea (Pisum sativum L.) and Other Legumes

“…did not demonstrate an increased resistance to powdery mildew [ 97 ], and standing milkvetch ( Astragalus adsurgens Torr.) became even more susceptible to the disease when mycorrhized [ 98 ]. Taking all of the above into account, mycorrhiza undoubtedly benefits the plant, but it cannot be considered as the main and universal method of protection against powdery mildew.…”

Reproductive biology, ecological life history/demography and genetic diversity of the megagenus Astragalus (Fabaceae, Papilionoideae)

“…The herbaceous species of Astragalus are annuals or perennials, and the shrubs are perennials. Astragalus species have been reported to be mycorrhizal (Rose, 1981;Zhao et al, 1997;Barroetavena et al, 1998;Shi et al, 2006;Tian et al, 2006;Bai et al, 2009;Liu et al, 2018) and to fix nitrogen (Wilson & Chin, 1947;Looman, 1974;Shearer et al, 1983;Baskin & Baskin, 1989b;Faria et al, 1989;Murooka et al, 1993;Evans and Ehleringer, 1994;Gibson et al, 1998;Gao et al, 2001;Meinke et al, 2013).…”