【作者】 郑国琦；

【导师】 胡正海；

【作者基本信息】 西北大学 ， 植物学， 2011， 博士

【摘要】 中药枸杞子是我国大宗常用中药材之一。《中国药典》中收录的中药枸杞子的原植物为宁夏枸杞(Lycium barbarum L.),隶属于茄科(Solanaceae)枸杞属(Lycium L.),为多年生灌木,以干燥果实入药,主要的药用成分为枸杞多糖和总糖。由于果实是宁夏枸杞主要的药用部位和有效药用成分的贮藏器官,因此,果实的大小及果实内主要药用成分的含量就成为中药枸杞子质量评价的主要指标,而目前关于宁夏枸杞果实的形态发育规律、果实结构发育与果实糖分积累的关系以及环境因子对枸杞产量和品质的影响等方面尚缺乏系统研究。本文运用植物解剖学、植物生理学、组织化学和植物化学等方法,以道地药材宁夏枸杞为研究材料,对其果实的形态结构发育规律、果实结构发育与果实内初级光合产物和药用成分多糖和总糖积累的关系、果实中糖分积累与土壤环境因子的关系以及不同灌水量对果实糖分积累及其适宜灌溉量的确定进行研究,结果表明：宁夏枸杞果实的生长发育曲线特征表现为花后8d以前为其第一次快速生长期,花后8-24d为缓慢生长期,花后的24-34d是第二次快速生长期,属于典型的双“S”型。枸杞种子的生长曲线既不属于单“S”型,也不属于双“S”型,其特征表现为,果实的第一次快速生长期同样也是种子的快速生长期,但种子完成的生长比例快于果实完成的生长比例,此期种子内胚乳生长快；当果实进入缓慢生长期,种子此时也表现出缓慢生长的特性,且种子长度和宽度的增加速率均显著低于果实第一次快速生长期种子的生长速率,此期种子主要进行胚的分化；在果实的第二次快速生长期,果实体积和重量迅速增加,而种子的长度和宽度增加很少,此期种子内仅胚进一步增大,从而反映枸杞果实的发育进程与种子发育进程存在相关性。宁夏枸杞果实叶绿体内不积累淀粉,这可能与果实本身光合色素含量低,外果皮无气孔器,自身光合作用合成的光合产物较少有关,以后随果实发育成熟,叶绿体内的类囊体结构逐渐解体转变为有色体。组织化学和超微结构研究表明,在果实转色(花后24d)以前果实的造粉体内有大量淀粉粒的存在,但在果实第二次快速生长期,果实内的淀粉粒分解、消失,因此,淀粉是宁夏枸杞果实发育过程中碳水化合物的一种暂时贮存形式,淀粉的大量形成有利于造成源库间递减的糖浓度梯度的形成和加速碳水化合物从韧皮部向果实中的卸载,对维持果实早期的库强起到了重要作用,但随着第二次快速生长期果实体积的增加,库强进一步增强,淀粉体内的淀粉被淀粉酶分解转化为还原糖贮藏在果肉细胞中。成熟宁夏枸杞果实内糖的积累主要以果糖和葡萄糖为主的己糖积累型,蔗糖含量很低,且呈现出果糖含量>葡萄糖含量>蔗糖含量的变化规律。果实转化酶是调控枸杞果实己糖积累的关键酶,而且果实发育后期转化酶活性的大幅提高有利于源库间蔗糖浓度梯度的形成,进一步增强了果实的库强。果实超微结构研究表明,随果实的发育成熟,果实韧皮部筛分子筛域逐渐变宽,筛孔大而多,通过筛孔的物质运输十分活跃。伴胞属传递细胞类型。筛分子和伴胞间有胞间连丝联系,但SE/CC复合体与韧皮薄壁细胞间无胞间连丝联系,伴胞与相邻的韧皮薄壁细胞连接处的细胞界面发生质膜内突,整个筛分子／伴胞复合体与韧皮薄壁细胞之间形成共质体隔离,韧皮部糖分的卸载方式主要以质外体途径进行。韧皮薄壁细胞间的胞间连丝较多,而韧皮薄壁细胞与果肉库薄壁细胞的胞间连丝相对较少,而果肉库薄壁细胞间几乎无胞间连丝。果肉库薄壁细胞之间胞间隙较大,细胞壁和质膜内突间形成较大的质外体空间,为糖分在果肉库薄壁细胞之间的质外体运输创造了条件。囊泡参与了果实糖分的运输过程。不同发育时期枸杞果实内的枸杞多糖含量积累与葡萄糖、果糖含量均呈显著正相关,而与蔗糖含量呈显著负相关,枸杞总糖与葡萄糖和果糖含量呈极显著正相关,而与蔗糖呈不显著负相关,说明枸杞果实内的蔗糖代谢在枸杞药用成分多糖和总糖的形成过程中具有十分重要的作用。比较研究结果表明,产地为宁夏的宁夏枸杞品种宁杞1号多糖含量均高于引种到河北、内蒙古、新疆所产同品种果实内的多糖含量,同属于宁夏枸杞的宁杞1号果实内多糖含量也明显高于精杞1号,并且也表现出宁夏枸杞果实品质优于枸杞变种架杞果。果实内的葡萄糖和果糖的含量与HC03-含量呈显著正相关关系。葡萄糖含量与土壤中的Ca2+和Mg2+含量呈现极显著负相关。果实内的多糖和总糖含量与土壤全盐具有较强的正相关关系,枸杞多糖与土壤中的Ca2+和Mg2+含量呈极显著的正相关,总糖含量与土壤中的pH,Na+和Cl-含量呈显著正相关,说明土壤盐分在宁夏枸杞果实糖分积累方面具有重要的作用。土壤肥力因子中的速效钾含量对葡萄糖,果糖,蔗糖和总糖的积累有促进作用,而速效磷对多糖的积累有一定的促进作用,而过高的土壤有机质和速效氮不利于枸杞果实总糖含量的提高。因此在宁夏枸杞的栽培实践中,要加强宁夏枸杞果实产量与品质之间关系的协调,确保宁夏枸杞品质的优良。不同灌水处理的结果表明,随月灌溉定额的增加,枸杞果实内的葡萄糖、果糖和蔗糖含量呈现下降的趋势。多糖含量也表现出下降的趋势,但在0、450.0和900.0 m3hm-2处理下,枸杞多糖含量差异不显著。枸杞果实产量随灌水量的增加呈现增加的趋势,但当灌水量超过900 m3hm-2后,其产量增加不显著。枸杞根内次生木质部导管直径随灌水量的增加而逐渐增加,且两者呈极显著正相关；导管频率和导管面积比例的变化趋势一致,在灌水量为900 m3hm-2时最大,而纤维面积所占的比例在灌水量为900 m3hm-2时最小；而木薄壁细胞面积比例则与灌水量呈不显著正相关。茎内次生木质部导管直径在灌水量为900 m3hm-2时达到最大,导管频率则与灌水量呈极显著负相关；而茎次生木质部内导管面积比例在灌水量为450 m3 hm-2时最大；纤维面积所占的比例则与灌水量呈显著正相关；木薄壁细胞面积比例则与灌水量呈极显著负相关。枸杞根和茎内木射线频率随灌水量的增加而减少,且两者呈极显著负相关,即根和茎内木射线的横向运输功能随着灌水量的增加而减弱。可见,宁夏枸杞根和茎内次生木质部结构和组成分子的数量随灌水量而变化,但900 m3 hm-2灌水量可使枸杞的根茎导管直径增加,导管频率降低,有利于维持枸杞体内输水系统的有效性和安全性。月灌溉定额<900 m3hm-2时,随灌水量增加,枸杞的叶片面积、叶片厚度、栅栏组织厚度和叶片结构紧密度、叶片光合速率、瞬时水分利用效率和气孔限制值显著增加,而气孔密度和胞间CO2浓度则呈下降趋势；月灌溉定额>900 m3 hm2以后,叶片胞间C02浓度随月灌溉定额的增加呈上升趋势,而叶面积和气孔密度变化不显著,其他指标均呈相反的变化趋势。枸杞叶片蒸腾速率和气孔导度值以450 m3 hm-2处理最高,其他处理均低于对照。综合以上研究结果表明,900 m3hm-2的月灌溉定额可作为当前宁夏枸杞生产中进行合理灌溉的一个参考依据。更多还原

【Abstract】 "Gouqizi" has been used in traditional Chinese medicine. Chinese Pharmacopoeia took L. barbarum as only original plant of "gouqizi", which belong to the genus Lycium in the family Solanaceae is a perennial shrubs, and dry fruits is the main medical parts, which was rich in Lycium barbarum polysaccharide(LBP) and total sugar. Due to dry fruits is not only the main medical parts but also is the organ in which the major components accumulate, the indexes of fruit size and major components contents were very important to evaluate the quality of the fruit of Chinese wolfberry, while the studies, which were the morphology, structure and development of fruits, the relationship between structure and sugar accumulation in fruit and the effects of soil microenvironments on the yield and quality of fruit, were not been studied at present. Anatomical, physiological, histological and phytochemial methods were used to investigate the structural features and the development of fruit of L. barbarum, the relationship between structure and primary photosynthesis production and medical components accumulation in fruit and the effects of soil factors on sugar accumulation, and different irrigation amounts on sugar accumulation and its suitable irrigation amounts. The main results showed that:The fruit growth curve of L. barbarum belongs to double "S" curve, and could divide into three stages. The first rapid stage spanned 8 days after blossom, then, it followed by a slow growth stage (8-24 days after blossom),and the second rapid growth stage (24-34 days after blossom). While the seed growth curve of L. barbarum was not only single "S" curve, but also double "S" curve. The first rapid stage of fruit was also the first rapid stage of seed, but the ratio of seed growth increasing was more than that of fruit, and the increasing of endosperm in seed was notable. During a slow growth stage of fruit, the increasing ratio of length and width were lower than those of seed in the first rapid stage, and embryo differentiation took place in seed during this period. During the second rapid growth stage, the volume and weight of fruit significantly increased, on the contrary, the length and width were almost not increasing, only embryo gradually grew up. These above results indicated that the morphology development of fruit was regulated and controlled by the seed development. The starch grain was not observed in chloroplast, the reason which caused were lower photosynthetic pigment content, without stomatal apparatus in pericarp and weak photosynthesis of fruit. The chloroplast converted chromoplast in ripe fruit. The amyloplast enriched much more starch grain before veraison stage(24 days after blossom), but starch grain almost disappeared during the second rapid growth stage.The starch was a transient form of carbohydrate accumulation during fruit development, which was available to form sugar concentration gradient between "source" and "sink" and accelerate sugar unloading from phloem and played an important role in maintain the sink capacity in early phase fruit. With the volume of fruit increasing, the sink capacity also became more and more stronger, and starch was degraded into reducing sugars by the action of amylase and accumulated in fruit parenchyma cell.The sugar accumulation mainly occurred in the form of hexoses, with the ordering of contents in ripe fruit:fructose> glucose> sucrose. Invertase activities were the key enzymes to control the hexoses accumulation in fruit, and the increasing of invertase was available to enhance the sink metabolism in later stage of fruit development.With the fruit growing, the sieve plate with large and much sieve pores, where active substance transport was observed in SE. Most, if not all, of the CC were transfer cells. Numerous plasmodesmata were observed between SE and CC (SE/CC), but there were almost no plasmodesmata between the SE/CC complexes and phloem parenchyma cell. Plasma membrane invagination was observed in adjacent between companion cell and phloem parenchyma cells. There was a symplasmically isolated between the SE-CC complex and its surrounding cells over the fruit development, which was available to sugar phloem unloading by apoplast pathway. Numerous plasmodesmata were also observed between the phloem parenchyma cells, On the contrary, there were almost no plasmodesmata between phloem parenchyma cell and fruit parenchyma cell and even between fruit parenchyma cell. The larger intercellular space among the fruit parenchyma cell and apoplast space caused by cell wall and plasma membrane invagination, which were in favour of sugar post-phloem transporting by apoplastic pathway. Vesicles were observed to participate in assimilates unloading and transporting.The content of LBP was positively correlated with those of total sugar, glucose and fructose, while on the contrary, negatively correlated with that of sucrose in different development stage fruits. Besides, the content of total sugars was positively correlated with those of glucose, fructose and sucrose in different development stage fruits. These results indicated that sucrose metabolism plays an important role in the formation of LBP and total sugars in the fruit of L. barbarum.The polysaccharide content of L. barbarum in Ningxia region (Ningqi No.1) was higher than not only those of the same variety in Hebei, Xinjiang and Inner Mongolia, but also those of different varieties (Jingqi No.1) in Xinjiang or species (Jiaqiguo, L. chinese) in Hebei. In terms of medicinal utility, the quality of L. barbarum in Ningxia region was superior to that of its cospecific counterparts in other regions as well as that of L. chinese. The soil HCO3- was significantly correlated with the content of glucose and fructose contents. The content of glucose was found to correlate significantly and negatively with Ca2+and with Mg2+. The content of soil total salt was non-significant and positive correlated with LBP and with total sugar. The content of LBP was significant and positive with Ca+and with Mg2+. The total sugar was significantly positive correlated with soil pH, Cl-and with Na+. These results showed that soil total salt played an important role in growth and development of L. barbarum. Meanwhile the content of total sugar was significantly and negatively correlated with soil organic matter and available nitrogen. Therefore, the contradiction between the yield and quality should be coordinate properly, so as to improve the quality of L. Barbarum.With the increasing of irrigation amount, the contents of glucose, fructose, sucrose and polysaccharide were decreased, but polysaccharide content was not existed significant difference under 0,450 and 900 m3 hm-2 irrigation amount per month. When the irrigation amount per month was less than 900 m3 hm-2, fruit yield was increasing, while irrigation amount more than 900 m3 hm-2, there was no significant effect of irrigation amount on the fruit yield.With the increasing of irrigation amount, the vessel diameter of root became more and more wider, and the more significant positive correlation existed with them. Vessel frequency and ratio of vessel area to secondary xylem area were the highest under 900 m3 hm-2. The ratio of fibre area to secondary xylem area decreased at first and then increased, and the value was the lowest under 900 m3 hm-2. The ratio of parenchyma cell area to secondary xylem was non-significant positive correlation with different irrigation amount; Vessel diameter of stem was the highest under 900 m3 hm-2. The more significant negative correlation was displayed between them. The ratio of vessel area to secondary xylem area was the highest under 450 m3 hm-2. The ratio of fibre area to secondary xylem area became more and more increased, and the significant positive correlation existed with them. However, the change of the ratio of parenchyma cell area to secondary xylem was opposite to fibre in stem; The ray frequency of root and stem were decreased with the increasing of irrigation amount, and displayed the more significantly negative correlation between ray frequency and irrigation amount, respectively. The decreasing of the ray frequency of secondary xylem indicated the weakening of horizontal transportation function in root and stem. Therefor, with the increasing of irrigation amount, the number of molecules of the structures and composition of secondary xylem of root and stem of L. barbarum changed.900 3 hm-2 irrigation quato per month could cause the increasing of vessel diameter increase, but reducing the frequency, so as to maintain suitable efficacy and safety of water system is in L. barbarum.When the irrigation amount per month was less than 900 m3 hm-2, the leaf area, leaf thickness, palisade tissue thickness, CTR, net photosynthetic rate (Pn), leaf intrinsic water use efficiency (WUE) and Ls all significantly increased with irrigation quota per month, while stoma density and Ci showed reverse trend. When the irrigation amount per month was more than 900 m3 hm-2, Ci increased with the irrigation quota per month whereas other indexes showed the contrary trend. There was no significant effect of irrigation amount on leaf area and stoma density. Highest transpiration rate and Gs were recorded under irrigation quota 450 m3 hm-2 per month. Therefore, in terms of saving water,900 m3 hm-2 was suitable irrigation quota per month for L. barbarum.更多还原