title: Regulation of Vapor Pressure Deficit by Greenhouse Micro-Fog Systems Improved Growth and Productivity of Tomato via Enhancing Photosynthesis during Summer Season.
abstract: The role of a proposed micro-fog system in regulating greenhouse environments and enhancing tomato (Solanum lycopersicum L.) productivity during summer season was studied. Experiments were carried out in a multi-span glass greenhouse, which was divided into two identical compartments involving different environments: (1) without environment control and (2) with a micro-fog system operating when the air vapor pressure deficit (VPD) of greenhouse was higher than 0.5 KPa. The micro-fog system effectively alleviated heat stress and evaporative demand in the greenhouse during summer season. The physiologically favourable environment maintained by micro-fog treatment significantly enhanced elongation of leaf and stem, which contributed to a substantial elevation of final leaf area and shoot biomass. These improvements in physiological and morphological traits resulted in around 12.3% increase of marketable tomato yield per plant. Relative growth rate (RGR) of micro-fog treatment was also significantly higher than control plants, which was mainly determined by the substantial elevation in net assimilation rate (NAR), and to a lesser extent caused by leaf area ratio (LAR). Measurement of leaf gas exchange parameters also demonstrated that micro-fog treatment significantly enhanced leaf photosynthesis capacity. Taken together, manipulation of VPD in greenhouses by micro-fog systems effectively enhanced tomato growth and productivity via improving photosynthesis during summer season.
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Dalong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Zhongdian
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Jianming
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Yibo
authors.initials: Y
authors.lastname: Chang
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Qingjie
authors.initials: Q
authors.lastname: Du
authors.affiliation: College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Tonghua
authors.initials: T
authors.lastname: Pan
mesh_terms: D051639:Gardening / Q000379:methods*; D018551:Solanum lycopersicum / Q000254:growth & development*; D018515:Plant Leaves / Q000254:growth & development*; D018547:Plant Stems / Q000254:growth & development*; D013227:Steam; D055548:Vapor Pressure
chemical_list: D013227:Steam