摘要
以马铃薯品种"大西洋"的试管苗为材料,在5个不同镁浓度(0、188、375、750、1 500μmol·L^(-1))的MS培养基上培养,20 d后测定生理和形态指标,研究了低镁胁迫对马铃薯试管苗叶绿素含量和碳水化合物积累与分配以及根系形态建成的影响。结果表明:试管苗的总叶绿素、叶绿素a(Chla)和叶绿素b(Chlb)含量以及根冠比、总根长、根表面积、根体积和侧根数均为缺镁(0μmol·L^(-1))处理最低,分别比对照(1 500μmol·L^(-1))降低42.3%、40.8%和46.2%以及96.4%、63.9%、54.1%、82.4%和89.9%;平均根直径和Chla/Chlb值为缺镁处理最高,分别较对照增加16.7%和9%;茎叶中淀粉、蔗糖、果糖和可溶性糖含量以及根中蔗糖、果糖和可溶性糖含量均为缺镁处理最高,分别比对照增加了58.5%、54.8%、59.7%和25.9%以及22%、46.7%和54.7%,而根中淀粉含量为缺镁处理最低,较对照降低32.8%。相关性分析表明,马铃薯试管苗茎叶中淀粉、果糖和可溶性糖含量与镁浓度均呈显著负相关。说明缺镁影响马铃薯试管苗的光合作用和碳水化合物代谢,大量碳水化合物在茎叶中积累,向根部的运输量减少,侧根形成减少,根冠比降低,抑制根系的形态建成。低镁水平下(750μmol·L^(-1))试管苗的叶绿素含量增加,更多的碳水化合物向根部运输,根冠比增大,促进根系的形态建成,与正常镁水平(1 500μmol·L^(-1))下马铃薯试管苗指标变化相同,差异不显著,表明含750μmol·L^(-1)Mg^(2+)的MS培养基适宜于马铃薯试管苗的生长和发育。
Potato cultivars “Atlantic” plantlets in vitro were cultured on liquid MS medium with low-Mg 2＋ concentration（0,188,375,750,1 500 μmol·L -1 ）. Physiological and morphological indexes were determined after^20 d culture and showed that under non-Mg 2＋ treated condition, the total chlorophyll content, chlorophyll a content and chlorophyll b content, root/shoot ratio, total root length, root surface area, root volume, lateral root number of plantlet in vitro were the lowest. Compared with the control, the above indexes were decreased by 42.3%, 40.8%, 46.2%, 96.4%, 63.9%, 54.1%, 82.4% and 89.9%, respectively. The average root diameter and Chla/Chlb reached the maximum level under non-Mg 2＋ treated condition and compared with the control were increased by 16.7% and 9%, respectively. The starch content in shoots and the sucrose content, fructose content and soluble sugar content in shoots and roots were highest under non-Mg 2＋ treated condition, and compared with the control these indexes were increased by 58.5%, 54.8%, 59.7%, 25.9%, 22%, 46.7% and 54.7%, respectively. The starch content in roots was lowest under non-Mg 2＋ treated condition and compared with the control were decreased by 32.8%. The correlation analysis indicated that there existed a strong negative linear relationship between Mg 2＋ concentration and starch content, fructose content, soluble sugar content in shoots, respectively. These results indicated that under the treatment of Mg 2＋ deficiency, a large amount of carbohydrate was accumulated in shoots whereas less exported to roots. The lateral root number and root/shoot ratio were reduced, and the root system formation was totally inhibited. Under low Mg 2＋ concentration of 750 μmol·L -1 treatment, the chlorophyll content of plantlet in vitro increased and more carbohydrate was translocated to roots. The root/shoot ratio increased and the root system formation was promoted. These physiological and morphological indexes under 750 μmol·L -1 treatment of Mg 2＋ had no difference from that of normal Mg 2＋ treatment condition （control）. The MS medium containing 750 μmol·L -1 Mg 2＋ was also beneficial to growth and development of potato plantlet in vitro .
作者
袁剑龙
杨丽丽
王玉萍
王瑞新
张绍梅
周晓洁
余斌
张峰
YUAN Jian-long 1, YANG Li-li 1 , WANG Yu-ping 1,2 ,WANG Rui-xin 1 , ZHANG Shao-mei 1 ,ZHOU Xiao-jie 1 , YU Bin 1, ZHANG Feng 1(1. Gansu Key Laboratory of Crop Improvement and Germplasm Enhancement,Gansu Provincial Key Laboratory of Aridland CropScience, Lanzhou,Gansu 730070,China; 2. College of Horticulture, Gansu Agricultural University, Lanzhou, Gansu 73007)
出处
《干旱地区农业研究》
CSCD
北大核心
2018年第4期200-206,共7页
Agricultural Research in the Arid Areas
基金
国家重点研发计划(2017YFD0101905)
甘肃省高等学校科学研究创新团队项目(20BC-17)
关键词
马铃薯
试管苗
低镁胁迫
根形态
碳水化合物
potato
plantlet in vitro
lowmagnesium stress
root morphology
carbohydrates
