title: [Adaptability of cucumber plug seedlings to daytime temperature].
abstract: Cucumber plug seedlings were cultured in a phytotron to study their responses to different daytime temperature. The daytime temperature was controlled at 30 degrees C, 27 degrees C, 24 degrees C, 21 degrees C, 18 degrees C and 15 degrees C, and the night temperature was at 15 degrees C, with the thickness and length of hypocotyl, length and width of the first and the second leaves, dry matter accumulation of above- and underground parts, leaf moisture content, and leaf chlorophyll fluorescence parameters measured. Principal component analysis and clustering analysis were made to analyze the seedling quality under different temperature treatment. There existed significant differences in the test growth indices among different treatments, with the seedling quality decreased at the daytime temperature 24 degrees C > 21 degrees C > 27 degrees C > 30 degrees C > 18 degrees C > 15 degrees C. All the daytime/nighttime temperature treatments could be classified into three groups, i.e., optimum temperature (24 degrees C/15 degrees C), appropriate temperature (21 degrees C/15 degrees C), and inappropriate temperature, and the inappropriate temperature could be further subdivided into two groups, i.e., high-temperature inhibition (27 degrees C/15 degrees C, 30 degrees C/15 degrees C) and low-temperature inhibition (15 degrees C/15 degrees C, 18 degrees C/15 degrees C).
authors: Ministry of Education and Jiangsu Province Key Laboratory of Modern Agricultural Equipment and Technology, Institute of Agricultural Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China. zhaoqs1983@163.com
authors: Qing-song
authors: QS
authors: Zhao
authors: Ping-ping
authors: PP
authors: Li
authors: Ji-zhang
authors: JZ
authors: Wang
authors: Yong-guang
authors: YG
authors: Hu
authors: Bei
authors: B
authors: Gao
mesh_terms: D000222:Adaptation, Physiological; D000383:Agriculture / Q000379:methods*; D016000:Cluster Analysis; D018553:Cucumis sativus / Q000254:growth & development / Q000502:physiology*; D004780:Environment, Controlled; D025341:Principal Component Analysis; D036226:Seedlings / Q000254:growth & development / Q000502:physiology*; D013696:Temperature