Effects Of Different Cultivation Conditions On Yield, Agronomic Traits And Antioxidant Enzyme Activity Of Cassia Obtusifolia L

Semen Cassiae is a small variety of Chinese traditional herbal medicine,which has rich resources in China.The mature seeds of Cassia could be used as medicinal gradients,originally recorded in "Shennong's Herbal".It is one of the substances that can be used both as food and as medicine,according to the Ministry of Health of People's Republic of China.It is rich in essential nutrients and multi-functional therapeutic factors for many diseases.In clinical practices it has been widely used in treating hyperlipemia,hypertension,constipation,mycotic vaginitis,gastrointestinal heat type acne and for eye-refreshing.In addition it is also a very good healthy food material.Baked Semen Cassiae has anintense coffee aroma with a unique flavor and with excellent emulsibility and processivity.It can be made of various forms of healthy food product.And many healthy foods and drinks,such as Bitter Gourd-Semen Cassiae Healthy Drink,Semen Cassiae-Hawthorn Leaf Healthy Soft Candy,Nutritional and Healthy Ice-cream with Semen Cassiae,Healthy Fruit-Jelly with Semen Cassia,Sour Soya-Milk with Semen Cassiae,Semen Cassiae Beer,Fruit Wine with Semen Cassiae,Semen Cassiae Drinks,Tai Chi Healthy Pillows etc.have been developed and marketed for the prevention and treatment of myopia,insomnia, various kinds of hypertension,with remarkable efficacy and significant role in health protection.All these products are welcomed by vast number of consumers.According to statistics,the number of proprietary Chinese medicines with Semen Cassiae ingredient recorded in "Chinese Pharmacopoeia" and "Ministry of Health Drug Standards" reached more than 80.At present,the resources of Semen Cassiae are mainly from cultivation.In addition to the production of medicines,Semen Cassiae cultivation is also good for soil improvement.Its excellent adaptation and great potential for development enables it to have a wide range of medicinal value.In this paper,the main agronomic traits,antioxidant enzyme activities of superoxide dismutase(SOD),peroxidase(POD) and catalase(CAT),and the main effecting anthraquinones in the seeds of Cassia obtusifolia L cultivated in different densities and in open field and greenhouse were investigated and compared,in a hope to find an economic,rational cultivation mode of Cassiae obtusifolia L in Chongqing to guide the cultivation and production of Cassia in this region.The results are as follows:1.Effects of Different Cultivating Conditions on Yield and Agronomic Traits of Cassia obtusifolia LWith the increase of planting densities,yield per Mu increased gradually,and then with the density increase,the yield began to decline.The optimum planting density of Cassia obtusifolia L was found to be about 8247 per Mu,corresponding to a maximum yield of about 265kg per Mu.Statistics analyses on the various agronomic traits at different planting densities show that the difference of the mean value of agronomic traits was not significant.The mean number of pods per plant and weight per 1000 seeds were decreased with densities increasing.The total number of pods per plant from the density of 8000 plants per Mu was increased by 23.25%over the density of 5000 plants per Mu and the weight per 1000 seeds dropped 5.43%;the total number of pods per plant from the density of 11000 plants per Mu was increased by 4.42%over the density of 8000 plants per Mu and the weight per 1000 seeds dropped 12.81%.However,the later increase in pods and in density can not compensate for the drop of yield,as regard to the total yield.This was in good accordance with the deduced yield equation versus density:y=-66.082+8.02×10^-(2)x—4.8622×10^-6x².The difference of the open field and greenhouse cultivation at the same density (8000 plants/Mu) on agronomic traits were significant.The mean height,the mean number of pods per plant,the mean length and number of pods of the first branch, pods on the main stem,and number of seeds per pod were significantly higher in open field than in greenhouse;while in greenhouse,the mean lehgth of pod,the mean weight of husk,the mean weight of the whole pod,and the weight per 1000 seeds were higher than in the open field.2.Effects of Different Cultivating Conditions on the Activity of Antioxidant EnzymesEffect of different planting densities on the activity of SOD,POD and CAT in corresponding plant parts was not significant statistically.But the activity of each enzyme between different plant parts showed extreme significance.The activity of SOD had a decreasing order of roots＞leaves＞flowers经stem; the activity of POD had a decreasing order of roots＞stern/leaves＞flowers;and the activity of CAT had a decreasing order of leaves＞roots＞flowers＞stem.There were some differences in the activity of each enzyme between the open filed and greenhouse cultivation in corresponding plant parts,but they were not significant.3.Comparison of the Main Active Ingredient(anthraquinone) content of Cassia semen between different Cultivating ConditionsAt different planting densities,the contents of free anthraquinones and total anthraquinones were different,but the difference was not significant.However,it was found that the contents of free anthraquinones and total anthraquinones from greenhouse cultivation were higher(0.756%and 0.936%respectively) than those from open field cultivation(0.5795%and 0.7585%respectively).Although in greenhouse the size of seed and the content of anthraquinnones were higher than those in the open field,Cassia obtusifolia L is not suitable for cultivation in the greenhouse duo to its poor performance in the important agronomic traits and low yield.