高温对长春花生活史型形成和生理代谢的影响

Effect of high temperature on life cycle forms and physiological metabolisms of Catharanthus roseus

长春花(Catharanthus roseus)是重要的药用植物,广泛栽植于热带和亚热带地区。高温(≥40℃)是其生活史过程中常见的胁迫因子之一。为了研究高温对植物能量在营养和繁殖上分配格局和生理代谢的影响,运用生活史型理论与方法研究高温和对照温度条件下长春花生活史型和生理代谢动态特点。主成分分析法(Principal component analysis,PCA)对营养生长(Vegetativegrowth,V)、有性生殖(Sexual reproduction,S)和无性繁殖(Clone reproduction,C)等3类15种性状进行统计,发现4周后高温与对照温度条件下长春花生活史型划分结果分别为V0.480S0.487C0.032和V0.604S0.385C0.010。对高温处理过程中可溶性糖、生物碱和抗氧化剂的代谢规律研究发现,蔗糖含量在第4周增加了约7倍,达到了(1.41±0.23)mg/g;文朵灵、长春质碱和长春碱等3种生物碱在第2周增加了2倍,峰值分别达到(6.0±0.63)mg/g、(3.8±0.63)mg/g和(35.6±2.8)μg/g;还原性谷胱甘肽(glutathione,GSH)从(153.3±11.8)nmol/g升高到(348.7±19.9)nmol/g,氧化型谷胱甘肽(GSSG)由(54.5±9.27)nmol/g增加至(149.2±10.1)nmol/g,均增加了1倍以上,GSH/GSSG比值则呈持续下降趋势。结果表明,高温使长春花能量固定总量增加了1倍以上,促进了有性繁殖和无性繁殖的投入,降低了营养生长方面的投入比例,这种能量分配格局的变化伴随着显著的生理代谢变化。

Catharanthus roseus has been widely cultivated around sub-tropic and the tropics, due to the pharmaceutical application in cancer cure. High temperature （ ≥40℃ ） is the commonest stress factor during growth and development of C. roseus, exerting marked influences on allocating patterns of energy in vegetative growth and reproduction process and physiological metabolisms. In this paper, life cycle forms and physiological metabolism dynamics under different temperature were determined. Investigation of principal component analysis （PCA） on 15 kinds of phenotypic characteristics, separately being related to vegetative growth, sexual and clone reproduction, was conducted. The results showed that the life cycle forms of C. roseus under high and control temperature were V0.480 S0.487 C0.032 and V0.604 S0.385 C0.010 . The investigations on some physiological metabolites, including soluble sugar, alkaloids and anti-oxidants affected by high temperature revealed that at the fourth week of treatment, there was about 7-fold elevation of sucrose content, arriving at （ 1.41 ± 0.23） mg/g. The concentrations of vindoline, catharatnhine and vinblastine increased to peak values of （6.0 ± 0.63） mg/g,（3.8 ± 0.63） mg/g and （35.6 ± 2.8）μg/g, 2-foht higher than the original values. The content of Glutathione （GSH） and its oxidative form GSSG were observed to be enhanced about more than 1-fold by high temperature, respectively from （153.3 ± 11.8） nmol/g to （348.7 ± 19.9） nmol/g, from （54.5 ± 9.27） nmol/g to （ 149.2 ± 10.1 ） nmol/g. While the ratio of GSH/GSSG decreased step by step during this course. These results indicated that high temperature promoted assimilation and accumulation of resources and energy allocations into sexual and clone reproductions, with repressed distributions of resources to vegetative growth. The changes of life cycle forms, at the same time, was followed with coordinated variations of primary and secondary metabolisms affected by high temperature.