Impacts of Constitutive and Induced Benzoxazinoids Levels on Wheat Resistance to the Grain Aphid (Sitobion avenae)

Abstract

Benzoxazinoids are important secondary metabolites in gramineae plants and have inhibitory and toxic effects against a wide range of herbivore pests. However, the relationship between benzoxazinoid level and plant resistance to aphids remains controversial. In this study, we investigated the relationship between benzoxazinoids composition and concentration in wheat leaves and the resistance to the grain aphid Sitobion avenae. Overall, six benzoxazinoids were detected and identified by mass spectrometry based metabolites profiling, including three lactams, two hydroxamic acids, and one methyl derivative. The constitutive levels of these benzoxazinoids were significantly different among the wheat varieties/lines. However, none of these benzoxazinoids exhibited considerable correlation with aphid resistance. S. avenae feeding elevated the level of 2-O-β-D-glucopyranosyloxy-4,7-dimethoxy-(2H)-1,4-benzoxazin-3(4H)-one (HDMBOA-Glc) and reduced the level of 2-O-β-D-glucopyranosyloxy-4-hydroxy-7-(2H)-methoxy-1,4-benzoxazin-3(4H)-one (DIMBOA-Glc) in some of the wheat varieties/lines. Moreover, aphid-induced level of DIMBOA-Glc was positively related with callose deposition, which was closely associated with aphid resistance. Wheat leaves infiltrated with DIMBOA-Glc caused a noticeable increase of callose deposition and the effect was in a dose dependent manner. This study suggests that the constitutive level of benzoxazinoids has limited impact on S. avenae. Aphid feeding can affect the balance of benzoxazinoids metabolism and the dynamic level of benzoxazinoids can act as a signal of callose deposition for S. avenae resistance. This study will extend our understanding of aphid–wheat interaction and provides new insights in aphid-resistance wheat breeding.

Two New Alkaloids from Roots of Zea mays and Their Cytotoxic Activity against Hep3B and SW480 Cells

“…1 H-NMR (600 MHz, CD 3 OD) spectrum of compound 1 (Table 1 2); [9] The HMBC correlations of δ ). [10] By comparing with the data in the literature, the 13 C-NMR data of compound 1 exhibited C-2 (δ 98.34) and C-1' (δ 105.58), allowing the determination of the absolute configuration of 1 as 2 S. Accordingly, the structure of 1 was determined and named zealisnge A.…”

Effects of Crop Resistance on the Tritrophic Interactions between Wheat Lines, Schizaphis graminum (Hemitera: Aphididae), and Propylaea japonica (Coleoptera: Coccinellidae)

“…The other sister lines, ‘186Tm39’ and ‘186Tm47’, were the progeny of the hybrid of wheat T. aestivum variety 186 and T. monococcum . Accordingly, ‘98-10-30’ is a wheat line that is relatively resistant to ‘98-10-19’, and ‘186Tm47’ is more relatively resistant than ‘186Tm39’ to the English grain aphid [ 29 ]. Interestingly, the resistance of ‘98-10-19’ to S. graminum was greater than that of ‘98-10-30’, even over the entire year.…”

“…Notably, these wheat lines have different resistance to Sitobion avenae (Fab.) [ 29 ]. However, the resistance statuses of these four wheat lines to greenbugs have not been investigated.…”

Responses of Six Wheat Cultivars (Triticum aestivum) to Wheat Aphid (Sitobion avenae) Infestation

“…The wheat resistance level was identified as described by Painter [ 29 ] and previously used in other studies [ 30 , 31 ]. Aphid resistance level is categorized into 7 grades ( Table 1 ), which include: immune (I), highly resistant (HR), moderately resistant (MR), low resistant (LR), low susceptible (LS), moderately susceptible (MS), and highly susceptible (HS).…”