Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 3, 2002
Publication Date: October 1, 2003
Citation: TISSERAT, B., VAUGHN, S.F. ULTRA-HIGH CO2 LEVELS ENHANCE LOBLOLLY PINE SEEDLING GROWTH, MORPHOGENESIS, AND SECONDARY METABOLISM. HORTSCIENCE. 2003. V. 38. P. 1083-1085. Interpretive Summary: Carbon dioxide (CO2) is one of the most important elements necessary for plant growth, yet little information about how CO2 atmospheres affects pine growth exists. We studied a broad range of CO2 atmospheric environments to ascertain the influence of CO2 on immature pine tree seedling growth and secondary metabolism in order to develop a technique to improve pine growth in a nursery environment. Loblolly pine (Pinus taeda L.) of Pinaceae, an important paper tree in Southeastern United States, was employed in this study. Our results indicate that this pine grows well with a broad range of CO2 atmospheres, and an optimal level was determined. In addition, secondary metabolites, (alpha- and beta-pinene) levels increase as the CO2 levels increase. We developed a CO2 pretreatment application that enhances pine tree growth and secondary metabolism to be employed in pine tree nursery operations to hasten pine tree production substantially.
Technical Abstract: The growth (fresh weight), morphogenesis (number of needles, roots, and shoot length), and monoterpene (alpha- and beta-pinene) levels of Pinus taeda L. (loblolly pine) seedlings were determined under 350, 1,500, 3,000, 10,000, or 30,000 umol mol**-1 CO2 after 30 days incubation under greenhouse conditions. Ultra-high levels (i.e., >3,000 umol mol**-1 CO2) substantially increased fresh weight, needle number, root number, and shoot length in loblolly pine seedlings compared to seedlings grown under ambient air (350 umol mol**-1 CO2). Loblolly pine seedling fresh weights, number of roots, shoot length, and number of needles from pine seedlings supplemented with 10,000 umol mol**-1 CO2 increased 120%, 171%, 36%, and 245%, respectively, when compared to loblolly pine seedling grown without any CO2 enrichment. In addition, alpha- and beta-pinene levels in seedlings increased under ultra-high CO2 levels. The dominant monoterpene, alpha-pinene, increased 46% in loblolly pine seedlings grown under 10,000 umol mol**-1 CO2 compared to levels obtained under 350 umol mol**-1 CO2.