Studies On Harvesting And Storage Characteristics Of Bupleurum Chinense’s Seeds From Qingchuan County

Bupleuri Radix (Chaihu) is one of the most frequently used medicinal plants all over the world for thousands of years. Aiming at the seed dormancy of Bupleurum chinense in Qingchuan County——a high quality local germplasm resource, this study has investigated the quality and yield of its seeds of different harvesting time, maturation and gorwing position. Simultaneously, I have analyzed the changes of the contents of nutrient substance, antioxidase activities and membrane permeability of seeds treated by artificial aging method, thus to study the seeds’harvesting and storage characterics, and to reveal the deterioration mechanism, as well as to offer technologies for the cultivation of B. chinense in Qingchuan County.1. The effects of harvesting time on B. chinense’s seeds’ yield and quality from QingchuanThere are obvious differences in yield and quality between seeds of the3harvesting time. By the comparison on the yield and quality indexes of the seeds harvested in3different time, we can see that as the harvesting time deferred, the yield of single plant raises, and the shrunken seeds rate decreases, while the contents of coumarins experiences a steady increase, and the germination rate decreases. Of the3kinds of seeds, seeds harvested in the black ripe time have the highest yield (ca.449grains per plant), and the lowest shrunken seeds rate (ca.31.20%), and the1000-grain weight is as much as0.965g, and they start germinating soon. Besides, the seeds’embryo rate increase to35.2%after4weeks’storage, while the realitively contents of coumatins stays in a high level. Compared their comprehensive yield and quality with Topsis approach, the seeds which harvested in the black ripe time ranks the first place, which followed by the brown ripe time and the yellow ripe time. As the harvesting time delays, the seeds’comprehensive quality increases, therefore, we could put off the seeds’harvesting time properly for the efficient seed production.2. The effects of maturation on B. chinense’s seeds’quality from QingchuanThe seeds’quality of different maturation is also different obviously from each other. The seeds can be classified into4groups——the green, the yellow, the brown and the black. I have compared their embryo rate, contents of nutrient substance, water absorbency, germination indexes and relative contents of coumarins, and the results show that they are different in the apparent size,1000-grain weight, water absorbency, germination indexes and anatomical structure, but all seeds’embryo rate can grow to a senior level after4weeks’storage. With the increase of maturity,1000-grain weight increases, and seedling quality enhances, at the same time, relative contents of coumarins also increases, while germination speed slows down, and germination rate decreases. Of the4groups, the green has the highest quality, which followed by the yellow, the brown and the black. Therefore, during the production the seeds should be harvested in time, hereby reducing the amount of overripe seeds, which have been indicated to be inferior seeds.3. The effects of growing position on B. chinense’s seeds’ quality from QingchuanThe seeds’quality of different growing position also differs from each other. It can be seen that seeds from the top have the heaviest1000-grain weight, and its water absorption is detente, and its seedlings are the strongest, and its embryo rate is the hightest, and its relative contents of coumarins is the lowest. All the quality indexes of the top are superior to the middle and the bottom. As a result, there is a definite relationship between the seed’s position and germination quality. The higher seed’ position is, the better its quality will be.4. The effects of harvesting with stalks on B. chinense’s seeds’ yield and qualityThere are significant differences on seeds’yield and germination quality harvested by the2harvesting approach——harvesting with stalks and harvesting directly when yellow. Compared with the seeds harvested directly, the seeds harvested with stalks have a heavier1000-grain weight(ca.1.163g), a earlier germinating starting, a higher germination rate, a stronger seedling quality, and a higher yield as much as456grains per plant, as a result, they have a superior comprehensive yield and quality. Harvesting with stalks could improve the seeds’yield and quality comprehensively, and it should be recognized as an efficient seeds harvesting method in seed production.5. Study on the deterioration mechanism of B. chinense’s seeds from QingchuanFrom the changes of the contents of nutrient substance, antioxidase activities and membrane permeability of seeds treated by artificial aging method, the seeds’deterioration mechanism is revealed. While the seeds deteriorates, their antioxidase (POD, SOD and CAT) activities decrease. After2days’treatment, SOD’s activity decreases to a rather low level, while3days’treatment may cause POD and CAT to a low activity level. Moreover, the seeds’deterioration is affected accompanyly by the decrease of the contents of nutrient substance and membrane permeability. Seeds of B. chinense from Qingchuan are easy to deteriorate, as1day’s artificial aging could cause the loss of germination.Taking the harvesting and storage characterics of seeds of different harvesting time, maturation, position and harvesting method into account, I suggest that seed production should do as follow:flower thinning when the late florescence to cut off the void flowers; harvest with stalks when the top seeds trun yellow, thresh after2weeks, then storage in cool, ventilated and dry environment; sow the seeds next year, while overyear seeds should not be applied for sowing.