Improving the use of rye (Secale cereale) for nematode management: potential to select cultivars based on Meloidogyne incognita host status and benzoxazinoid content

Abstract

Six geographically diverse cultivars of rye (Secale cereale), a wheat (Triticum aestivum) cultivar and hairy vetch (Vicia villosa) cultivar unstated were screened for Meloidogyne incognita host suitability. Chemical constituents of rye can suppress M. incognita, so the rye cultivars and wheat were also tested for benzoxazinoid content to determine if rye cultivar selection could be based upon plant chemistry. There was variation in M. incognita host status among the rye cultivars. Cultivars Aroostook, Elbon, Oklon and Wrens Abruzzi were the most resistant rye cultivars, with low numbers of M. incognita eggs/g dry root. Cultivar Wheeler had somewhat more eggs/g root than these cultivars, while cv. Merced supported nearly three times more eggs/g root than cv. Wheeler. Most of the rye cultivars were similar to each other in total benzoxazinoid content, although cv. Aroostook had the lowest amount of total benzoxazinoids. When data from roots and shoots were combined, more than 79% of the total benzoxazinoids in all six of the rye cultivars were comprised of the non-methoxy-substituted forms: i)

ScBx gene based association analysis of hydroxamate content in rye (Secale cereale L.)

“…It is well known that in rye DIBOA and GDIBOA are predominant in aerial parts, whereas DIMBOA and MBOA are predominant in roots (Frey et al 2009; Zasada et al 2007; Meyer et al 2009). For DIBOA and GDIBOA, compounds dominant in above-ground parts, our results are consistent with the previous study performed in the Institute of Soil Science and Plant Cultivation which reported their content in the aerial parts to be, respectively, five and two times higher than in the roots (Krzyżanowska et al 2006).…”

“…Rye HX have been mainly studied in the context of their role in allelopathy (Barnes and Putnam 1987; Tabaglio et al 2008; Gavazzi et al 2010) and their toxic impact on nematodes (Zasada et al 2005, 2007; Meyer et al 2009). Makleit (2005) reported a positive correlation between DIBOA content in two Secale species ( S. cereale and S. cereanum ) and their reaction with soil salinity.…”

Invasion, development, and reproduction of 3 Meloidogyne species on oat cultivar Tachiibuki, a nematode-suppressive fall crop

“…This includes a detailed examination of the giant nurse cells induced by nematodes invading the roots. Furthermore, as it appears improbable that the reduction in nematode damage in the field after fall cropping of Tachiibuki (Tateishi et al, 2008) is explained exclusively by the reduced reproduction rate of the nematodes in the oats, some reports suggest that Meloidogyne species are suppressed in an indirect way by the production of plant derivatives during cropping of gramineous nematode hosts (Sipes and Arakaki, 1997;Zasada et al, 2007). Therefore, it is important to characterize in detail the nematode-suppressive factors involved in the cultivation of sweet potato in combination with fall cropping of Tachiibuki under field conditions.…”

Impacts of Root Metabolites on Soil Nematodes

“…Rye cultivars with higher root concentrations of methoxy-substituted benzoxazinoids had the lowest numbers of M. incognita eggs. These cultivars were therefore suggested for soil incorporation as green manure to protect against root-knot nematodes (Zasada et al, 2007). In a greenhouse trial, soil infested with the root-knot nematode Meloidogyne incognita was treated with DIBOA (2,4-Dihydroxy-2H-1,4-benzoxazin-3(4H)-one) at concentrations ranging from 1.1 to 18 µg/g dry soil, and M. incognita egg production in cucumber roots decreased significantly at the highest concentration (Meyer et al, 2009).…”