Studies On Flowering Habit And Accumulation Of Seed Nutrient Of Angelica

Angelica (Angelica sinensis (Oliv.) Diels) is one of commonly used Chinese herbal medicines and authentic Chinese herbal medicines in Gansu Province, and it belongs to the perennial Apiaceae Angelica herb. Currently, the problems of varietal complexity,inferior seedlings was flooded in market and early bolting seriously affected the output and quality in Angelica production process. This study adopted microscopic observation, field testing, biochemical testing and statistical analysis etc. methods and means research to flowering and fruiting characteristics, nutrients dynamic changes in seed maturity and germination of different maturity of seeds. The aim of this study was to offer theoretical basis of Angelica varietal improvement and seedling breeding. The results were as follows:1. Florescence of three-year-Angelica was the early of July to the end of August, flowering stage was about in mid-July, single florescence was 4 to 5 days. Single florescence could be divided into six periods:bud stage, early flowering, male period, sexual period, female period and wither period according to its pattern and male and female characters functional expression. Stamens of Angelica flowers was first ripe, and its stigma did not show peroxidase activity, reaction solution had not response and the stigma had no receptivity in 1 to 2 days before flowering. Stigma receptivity was the best in the fourth day. Angelica pollen viability gradually increased and reached the maximum in the third day, about 92.1%, then declined day by day. so the best time of artificial pollination was the third to fourth days after flowering.2. Measuring OCI (hybrid index) and evaluating breeding system according to the standards of Dafni. The result of flower observation showed that the hybrid index was OCI =4, some of breeding system was self-compatible, intercrossing and requiring pollinators. The results of the field testing indicated that Angelica maturing rate was the highest under natural conditions, was 81.0%, and its didn't have apomixis phenomenon. The ripening rate of mesh bag treatment was higher than paper handling showed that Angelica pollination process needed certain pollinators. Different strains and different flower artificial pollination was similar with the strains and different flowers artificial pollination showed that different strains and different flowers was compatible with strains and different flowers. Combining these two results that pollination systems of Angelica were intercrossing (different strains, different flowers) affinity and self-compatible affinity, and the main was intercrossing, and sometimes depended on pollinators. The results were consistent with hybrid index and pollen/ovule ratio tests.3. The trend of thousand fresh weight and moisture content in different maturity period were "S", and its process was slow growth-rapid growth-rapid decrease-slow down; Soluble sugar content in seeds was far lower than the starch content and protein content, and its trend was not obvious throughout the ripening process; Starch content was slowly increasing trend, and reached the maximum which was 7.45%(P<0.01)in mid-September, and then fell slowly to the end of September which was 4.77%; protein content was "down-slow up-slow down-rise slowly-slow down "wavy irregular trend. Such irregular changes might be caught by the climate, soil nutrient changes, or the sampling or testing errors, which needed to do further study.4. The change of germination rate, germination energy and germination index of Angelica seed in different maturity were higher, and its overall trend like a parabola. Germination rate of Seed gained in late August (August 24, August 29)was very low (10.33%); Germination rate of Seed collected in early September (September 5, September 9) was the highest (90.06%), and then gradually decreased. The trend of germination energy and germination index were similar with the trend of germination rates. In early September, seeds were at the flowering stage and its color was white with pink spots, and the main reason of the higher germination rate in this time was that physiological and biochemical activities could conduct in the appropriate environment where there was relatively higher moisture content, lower levels of starch, protein and other macromolecules. With the reduction of water content and accumulation of nutrients, the germination ability was decreasing. In production, seed can be direct sowing and seedling when it was in the flowering stage.