Anatomical and Chemical Responses of Eastern White Pine (Pinus strobus L.) to Blue-Stain (Ophiostoma minus) Inoculation

Forests

Sourav Chakraborty¹  MiT. Phan¹  Kevin Blascyk¹  Joseph Barsky²  Adriana Arango-Velez²  Walid El Kayal³ 

[1] Department of Chemistry and Biochemistry, Central Connecticut State University, New Britain, CT 06050, USA;Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, New Haven, CT 06504, USA;Department of Forestry and Wood Technology, Faculty of Agriculture, Alexandria University, EL-Shatby, 21545 Alexandria, Egypt;

关键词: southern pine beetle;    Ophiostoma minus;    eastern white pine;    traumatic resin ducts;    phenolics;    monoterpenes;   

DOI  :  10.3390/f9110690

来源: DOAJ

【 摘 要 】

The increases in temperature have recently allowed the southern pine beetle (Dendroctonus frontalis Zimm.; SPB) and its associated fungi to expand its natural range to northern pine forests. In this study, vigorous eastern white pine mature trees were used to evaluate constitutive and induced response to the southern pine beetle, using O. minus as a proxy. We evaluated histological and chemical changes in P. strobus in response to the fungus at 28- and 65-days post inoculation (dpi). Inoculation with O. minus resulted in an induced defense response as evidenced by the increased production of traumatic resin duct, and lesion development surrounding the site of infection. Starch granules accumulated in the epithelial cells surrounding the resin ducts of inoculated trees. Chemical analyses showed that among phloem phenolics, epi/catechin and three unknown compounds were significantly upregulated at 28 dpi due to fungal inoculation. Several phloem terpenoids (α-pinene, β-myrcene, limonene, terpinolene and β-pinene) were significantly increased in inoculated trees compared to controls at both, 28- and 65-dpi. Continuous production of these terpenoids (up to 65 dpi) can be energetically costly for P. strobus as carbohydrate reserves fund monoterpene synthesis, reducing carbon availability necessary for tree development. Induced phenolics along with monoterpenes production and traumatic resin ducts observed in these trees, suggests that vigorous white pine may sustain endemic populations of southern pine beetle and vectored fungi.

【 授权许可】

Unknown