Effects Of Conservation Tillage And Leaves Harvesting On Yield And Quality Of Isatis Indigogitica Fort. In Dryland

Isatis indigogitica Fort growth and development dynamic,dry matter accumulation, water use efficiency,the yield and the quality was studied under conservation tillage;And also studied the effects of different harvesting period and harvesting times on the yield and the quality of Radix Isatidis and Folium Isatidis under traditional tillage. The main results were as follows:1. Under conservation tillage, dryland Isatis indigogitica Fort leaves'all indicators had the same trend,all had single-peak curve, had a peak value,and peak value of different treatments appeared in different periods;Root diameter and root length changed by the same trend, root diameter and root length of the trend increased with reproductive period,, root growth had a model that the first growed then enlarged;General trend of dry matter accumulation of the ground and the underground portion increased, dry matter accumulation of the underground portion of traditional tillage was the largerest (3.82g/ plant), next was No-tillage and straw cover (3.68g/ plant), the lowest was no-tillage (3.65g/ plant); No-tillage and straw cover in three treatment was the lowest.2. Different conservation tillage had different effects on yeild of Radix Isatidis and Folium Isatidis. Traditional tillage was both the largerest, the yeild of Radix Isatidis and Folium Isatidis were respective 3820kg·hm^-2 and 1750kg·hm^-2, no-tillage is lower , the yields were 3680 kg·hm^-2and 1570 kg·hm^-2;No-tillage and straw cover was the lowest , only respectively 3650 kg·hm^-2 and 1310 kg·hm^-2. Active ingredients of Radix Isatidis and Folium Isatidis: averaged water-soluble extract 57.03%,51.34%, ethanol-soluble extract 46.85%, 42.54%, Indirubin 0.0075%,0.0815%,Indigo0.1825% ,2.8911%. Three treatment were no significant differences, reached requirements of Chinese Pharmacopoeia.3. Under conservation tillage, Isatis indigogitica Fort'leaf water use efficiency was the highest in 8:00-10:00. The largest diurnal accumulation was No-tillage and straw cover(10.77μmolCO₂/mmolH2O). Field water use efficiency of traditional tillage was largest (11.00 kg·hm^-2·mm^-1), conventional tillage was higher than No-tillage, No-tillage and straw cover4.07%, respectively4.07% and 28.4%. 4. Different harvest period of Folium Isatidis had a significant differents on the yield and the quality of Radix Isatidis and Folium Isatidis. Harvested in August , yield of Radix Isatidis and Folium Isatidis were the highest (2130.33 kg·hm^-2, 5885.0 kg·hm^-2), increasing 32.27% , 218.4% than comparion. Harvested Folium Isatidis in different period, ethanol–soluble extract and Indirubin of Radix Isatidis and Folium Isatidis reath to Chinese Pharmacopoeia'requires,quality of Radix Isatidis and Folium Isatidis were the best in comparion treatment.5. Different harvest times of Folium Isatidis had a significant effects on the yield and the quality of Radix Isatidis and Folium Isatidis. Harvest Folium Isatidis could increase the yield of Folium Isatidis,but reduced the yield of Radix Isatidis, the quality of Radix Isatidis and Folium Isatidis.Harvest one, two or three times Folium Isatidis, the yield of Radix Isatidis was lower than comparion 18.3%, 58.6%, 67.4%, ethanol-soluble extract of Radix Isatidis was 42.50%, 42.24%, 31.77%, lower respectively 1.19%, 1.79%, 26.13% than that of comparion. Its water-soluble extract, indirubin, indigo content had reduced with increasing the times of harvesting.Yield of Folium Isatidis is harvest three times> harvest one times > harvest two times > no harvest ,respectively, 3920.4 kg·hm ^-2> 3751.7 kg·hm^-2> 3381.7 kg·hm^-2> 1810.2 kg·hm^-2, harvest one times increased 107.3% than comparion, harvest two times increased 86.3%, harvest three times increased 116.6 %. Indirubin of harvest two and three times Folium Isatidis were higher than comparion, but the content of water-soluble extract, ethanol- soluble extract, indigo of comparion were the highest.