title: Deciphering the mechanism of β-aminobutyric acid-induced resistance in wheat to the grain aphid, Sitobion avenae.
abstract: The non-protein amino acid β-aminobutyric acid (BABA) can induce plant resistance to a broad spectrum of biotic and abiotic stresses. However, BABA-induced plant resistance to insects is less well-studied, especially its underlying mechanism. In this research, we applied BABA to wheat seedlings and tested its effects on Sitobion avenae (F.). When applied as a soil drench, BABA significantly reduced weights of S. avenae, whereas foliar spray and seed treatment had no such effects. BABA-mediated suppression of S. avenae growth was dose dependent and lasted at least for 7 days. The aminobutyric acid concentration in phloem sap of BABA-treated plants was higher and increased with BABA concentrations applied. Moreover, after 10 days of treatment, the aminobutyric acid content in BABA-treated plants was still higher than that in control treatment. Sitobion avenae could not discriminate artificial diet containing BABA from standard diet, indicating that BABA itself is not a deterrent to this aphid. Also S. avenae did not show preference for control plants or BABA-treated plants. Consistent with choice test results, S. avenae had similar feeding activities on control and BABA-treated plants, suggesting that BABA did not induce antifeedants in wheat seedlings. In addition, aminobutyric acid concentration in S. avenae feeding on BABA-treated plants was significantly higher than those feeding on control plants. Sitobion avenae growth rate was reduced on the artificial diet containing BABA, indicating that BABA had direct toxic effects on this aphid species. These results suggest that BABA application reduced S. avenae performance on wheat seedlings and the mechanism is possibly due to direct toxicity of high BABA contents in plant phloem.
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: He-He
authors.initials: HH
authors.lastname: Cao
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Xing-Xing
authors.initials: XX
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Zhan-Feng
authors.initials: ZF
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, and the Key Laboratory of Crop Pest Management on the Losses Plateau of Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Tong-Xian
authors.initials: TX
authors.lastname: Liu
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000613:Aminobutyrates / Q000633:toxicity*; D000818:Animals; D001042:Aphids / Q000187:drug effects / Q000502:physiology*; D001835:Body Weight / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects; D009195:Peroxidase / Q000378:metabolism; D052585:Phloem / Q000187:drug effects / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects; D014908:Triticum / Q000187:drug effects* / Q000201:enzymology / Q000469:parasitology*
chemical_list: D000596:Amino Acids; D000613:Aminobutyrates; C047667:3-aminobutyric acid; D009195:Peroxidase