The Dynamic Changes in Cold Tolerance of Ground-cover Chrysanthemum Growing in the Open Field during the Overwintering

The ground-cover chrysanthemum （Dendranthemaxgrandiflorum Kitamura） ＇Zixunzhang＇ was used as the experimental material in this study. The physiological and biochemical indexes of leaves, emergent rhizomes and roots from ＇Zixunzhang＇ growing in the open field during the autumn and winter in Beijing area were deter- mined. These indexes showed that root activities decreased slowly with the drop in temperature. The relative water contents of leaves and emergent rhizomes, and the water content of roots decreased. The activities of SOD, CAT and POD from leaves and emergent rhizomes were affected significantly by low temperature, but their change trends were different, which suggested that these 3 enzymes might play an interacted role in the formation of the cold tolerance of ＇Zixunzhang＇ mum, while the changes of the three enzyme activities in roots were little when the tem- perature dropped. With the significant increasing of the content of soluble sugar from leaves, the contents of soluble protein and proline declined overall; and the contents of osmotic regulation substances of emergent rhizomes and roots increased at first and then decreased. The correlation analysis indicated that the cold toler- ance of ground-cover mum ＇Zixunzhang＇ was related closely to relative water con- tents, SOD enzyme activity, soluble protein, soluble sugar and root activity. The morphological observation of leaves, emergent rhizomes and roots also showed that the survival of the ground-cover mum mainly depended on the cold tolerance of roots during the overwintering.

FAST BREEDING OF GROUND-COVER CHRYSANTHEMUM

The experiment of tissue culture of ground-cover chrysanthemum with the tip of shoots as the explant was made. On MS medium, with adding BA 3.0 mg/ L and NAA 0.01mg / L, the adventitious buds had the best multip1ication result. The best result for taking roots was obtained on 1 / 2 MS medium with adding NAA 0.1 mg / L. It had good result and a high survival rate for transplanting the young test-tube plants into soil whcn they were 3-4 cm high,with 5-7 rootlets (0.5- 1.0 cm in length). 30% of edible powdered sugar was uscd to replace sucrose in order to lower thc cost and the same results were obtained.

Comparison of Cold Tolerance in Three Ground-cover Chrysanthemum Cultivars during Wintering in the Open Field

[Objectives]Among many chrysanthemum types,the ground-cover chrysanthemum cultivar group has the characteristics of dwarf plant,long flowering period,rich color and strong resistance to stress.This study aimed to screen out cultivars with strong cold tolerance in order that they can be used for planting in urban green space and economic forests in northern cold areas,so as to enrich the plant community structures of landscape in cold regions.[Methods]Three ground-cover chrysanthemum cultivars,i.e.,‘Meiaihuang’,‘Xinhong’and‘Zixunzhang’,were selected as the experimental materials.During the wintering period in the field in Beijing,they were observed and measured for the changes of the morphological manifestations and the physiological indices,and the relationship between the indices and low temperature was analyzed.The cold tolerance of the three ground-cover chrysanthemum cultivars was also comprehensively evaluated.[Results]During the open-field overwintering period,the root activity of the three ground-cover chrysanthemum cultivars increased slowly with cooling,decreased at the freezing low temperature,and then increased again in early spring.With natural cooling,the membrane injury percentages(MIPs)of the leaves and foot shoots increased significantly,and the contents of malondialdehyde(MDA)increased;the contents of soluble sugar(SS)and proline(Pro)gradually accumulated,and the contents of SS and Pro in foot shoots increased significantly in late winter;and the superoxide dismutase(SOD)activity showed a similar trend of rising slowly at first and then increasing significantly.There were correlations between MIPs in the leaves and foot shoots of the three cultivars and other physiological indices:a significant negative correlation with MDA content,and a significant positive correlation with SS content,Pro content and SOD activity.[Conclusions]Combining the morphological manifestations and physiological indices,the cold tolerance of the three ground-cover chrysanthemum cultivars was evaluated by the subordinate function method.The results showed that the cold tolerance of the three ground-cover chrysanthemum cultivars ranked as‘Meiaihuang’>‘Xinhong’>‘Zixunzhang’.The strong cold tolerance of foot shoots and roots was the main reason that the three ground-cover chrysanthemum cultivars could overwinter in the open field.

地被菊间接体细胞胚发生途径的转基因受体体系的研究

采用三步培养法建立了地被菊花品种‘玉人面’间接体细胞胚发生途径的转基因受体体系。试验以地被菊花品种‘玉人面’茎段(节间)为外植体,研究了生长调节剂、光照强度等因子对其间接体细胞胚诱导和分化的影响,同时进行了抗生素敏感性试验。结果表明:胚性愈伤组织诱导培养基为MS+KT2.0 mg.L-1+2,4-D 2.0 mg.L-1+NAA0.5 mg.L-1,诱导15 d后,将获得的黄绿色致密颗粒状胚性愈伤组织转入胚性愈伤组织分化培养基MS+KT2.0 mg.L-1+2,4-D 1.0 mg.L-1+NAA0.5 mg.L-1中,诱导15 d后再转入MS+KT2.0 mg.L-1+NAA0.5 mg.L-1的分化培养基中培养20 d,光照强度为1 000～2 000 lx,胚性愈伤组织诱导率、分化率分别为95.3%、92.7%,平均每个外植体分化的芽数为17.8个,获得的再生芽的稳定性为99.5%。抗生素敏感性试验表明:地被菊花品种‘玉人面’间接体细胞胚发生途径的转基因受体体系中,卡那霉素选择压为20 mg.L-1;头孢霉素在胚性愈伤组织诱导时的选择压为300 mg.L-1,在胚性愈伤组织分化培养时选择压为100 mg.L-1。

一种降暑凉茶的研制

以菊花等传统降暑原料配制成一种适于夏季饮用的茶饮,结果表明:混合茶香气品质较好的适宜重量配比为菊花:金银花:荷叶=95:5:3,汤色品质较好的适宜配比为菊花:金银花:荷叶=90:5:3,滋味品质较好的适宜配比为菊花:金银花:荷叶=90:5:8,综合感官品质较好的适宜配比为菊花:金银花:荷叶=95:5:3。

鱼腥草、苦丁茶、杭白菊复合保健饮料工艺研究

以鱼腥草为主料,辅以苦丁茶、杭白菊,探讨鱼腥草、苦丁茶和杭白菊清凉复合保健饮料的最佳工艺配方。结果表明:将鱼腥草切成1～2 cm小段,经0.2%盐水浸渍、护色、汽蒸,与护色液按1∶0.8打浆,每100 g鲜鱼腥草出汁率可提高达140 mL,汁液色泽呈理想的浅黄色。复合饮料最佳配方为:鱼腥草汁的用量100 mL,黄原胶0.12 g,蔗糖脂肪酸酯0.08 g,甜味剂30 g(蔗糖∶乳糖∶木糖醇=10∶3∶2),酸味剂0.94 mL(含柠檬酸2.6%、酒石酸1.0%,抗坏血酸1.0%),苦丁茶汁21 mL,菊花汁5.3 mL。苦丁茶、杭白菊能有效改善鱼腥草饮料的风味。

河北香菊总黄酮提取工艺研究

对河北香菊(Chrysanthemum morifoliu‘HebeiXiangju’)中总黄酮提取方法进行了比较研究,同时采用索氏提取和超声提取方法,利用高效液相色谱法对总黄酮进行检测和含量测定,确定了提取总黄酮的最佳工艺条件。结果表明:各因素对河北香菊中总黄酮得率的影响大小顺序为乙醇浓度>提取温度>提取时间>料液比;河北香菊中总黄酮的最佳提取工艺为:乙醇浓度为90%、提取温度为65℃、提取时间为45min和料液比为1∶80。