title: [Effects of partial root excision on the growth, photosynthesis, and antioxidant enzyme activities of maize under salt stress].
abstract: A pot experiment was conducted to study the effects of partial root excision on the growth of two maize cultivars (Zhengdan 958 and Denghai 9) throughout their growth period and the photosynthesis and leaf antioxidant enzyme activities at grain-filling stage under salt stress. Four treatments were installed, i. e., control (no salt), low salt (0.2% NaCl), moderate salt (0.4% NaCl), and high salt (0.6% NaCl). Under low salt stress, the grain yield of Zhengdan 958 and Denghai 9 with partial root excision was increased by 13.1% and 31.4%, respectively, as compared with that of the cultivars with no root excision. At jointing stage, the growth of the cultivars with partial root excision was restrained, the root- and shoot dry masses under the same salt stresses being lesser than those of the cultivars with no root excision, but the growth under the conditions of no salt and low salt recovered quickly. At milk-ripe stage and under no salt and low salt conditions, the root- and shoot dry masses, leaf area, total root length, total root surface area, root activity, leaf chlorophyll content, and ear leaf net photosynthetic rate, stomatal conductance, transpiration rate, and CAT and POD activities of the cultivars with partial root excision were significantly larger than those of the cultivars with no root excision, while the shoot diameter and ear leaf MDA content were in adverse. Moderate and high salt stresses had greater effects on the cultivars with partial root excision. The root- and shoot dry masses, root morphology, and photosynthesis indices of the cultivars with partial root excision were smaller than those of the cultivars with no root excision, so did the grain yields. Throughout the growth period of the cultivars, the growth of the cultivars with partial root excision depended on the salt concentration, i. e., was promoted under no and low salt, and inhibited under moderate and high salt conditions.
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, China. zhanghong260@126.com
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Cui
authors.forename: Jia-Jia
authors.initials: JJ
authors.lastname: Meng
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Zhang
authors.forename: De-Yang
authors.initials: DY
authors.lastname: Shi
authors.forename: Shu-Ting
authors.initials: ST
authors.lastname: Dong
authors.forename: Ji-Wang
authors.initials: JW
authors.lastname: Zhang
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
mesh_terms: D000383:Agriculture / Q000379:methods; D010788:Photosynthesis / Q000502:physiology*; D018517:Plant Roots / Q000254:growth & development*; D012965:Sodium Chloride / Q000378:metabolism / Q000494:pharmacology*; D013312:Stress, Physiological / Q000502:physiology*; D013482:Superoxide Dismutase / Q000378:metabolism; D003313:Zea mays / Q000254:growth & development* / Q000502:physiology
chemical_list: D012965:Sodium Chloride; D013482:Superoxide Dismutase