The Effect Of Different Transmittance Of Needle Nets On The Growth And Quality Of Farmland-cultured Ginseng

As an important environmental factor,light directly affects the photosynthesis of plants and it has an important impact on the growth and development of plants.Ginseng is a shade plant but also needs ideal light conditions to obtain high yield.The regulation of light environment is very important for the farmland-cultured ginseng as a new way of ginseng cultivation.The experiment on farmland-cultured ginseng of diffrernt transmittance is carried out in this paper.The experiment is carried out at the ginseng base in Baishan City,Jilin province.We choose the 4-year-old farmland-cultured ginseng and design 7 transmittance test group of 10%,15%,20%,25%,30%,35% and 40%.The 25% transmittance as control group.The effects of different transmittance on the growth,yield,physiological and biochemical indexes and the content of effective components of ginseng were studied.The results show that:1.The experimental study showed that among the 7 treatment groups,the 20% and 30% transmittance treatment group had a more significant influence on the morphological indexes of ginseng,the highest of the 30% transmittance treatment group,the 20% transmittance of the stem height,the 20% and 30% transmittance in the treatment group,and the 30% transmittance treatment group,the main root length,the main root,the single fresh root weight and the level.M fresh root yield were the biggest and farmland ginseng fresh weight was positively correlated with light transmittance.2.The SOD,POD and CAT activities of ginseng leaves in the 7 treatment groups were the strongest in July.From June to September,they all increase firstly and then decrease;the content of MDA is the highest in September and the lowest in June,which is positively correlated with the increase of transmittance.Overall,among the 7 treatment groups,the activity of SOD,POD and CAT is the lowest in the 10% transmittance treatment group,and the difference is significant between the control group and the control group,the 40% transmittance treatment group is the highest.The MDA content is the highest in the 25% transmittance treatment group,and the 40% transmittance treatment group is the lowest,and the difference is not significant with the control group.The chlorophyll content of the 7 treatments reach the maximum in August,and the chlorophyll content decrease with the increase of transmittance.There is a positive correlation between relative chlorophyll content and transmittance.3.Among the 7 treatment groups,the content of polysaccharide in the 20% transmittance treatment group is the highest,followes by the 30% transmittance treatment group,and the 10% transmittance treatment group is the lowest.The total saponins content is the highest in the 30% transmittance treatment group and the lowest in the 10% treatment group.The content of the monomer saponins Rb1 is the highest in the 40% transmittance treatment group,and the lowest in the 10% transmittance treatment group and the difference is significant between the two.The content of Rg1 is the highest in the 15% transmittance treatment group,the lowest in the 40% transmittance treatment group and the difference is significant between the two.The content of Re is the highest in the 35% transmittance treatment group,the lowest in the 10% transmittance treatment group,and the difference is significant between the two.With the increase of transmittance,the total content of Panax glycol type saponin increase,while the total content of three alcohol saponin decrease.The change of light transmittance has a certain influence on farmland-cultured ginseng.The maximum value forms of the 4-year-old farmland-cultured ginseng under the condition of 20%-30% transmittance can be reached,which can be considered to be suitable for the growth and accumulation of ginseng in farmland.Under the condition of transmittance of 30-40%,the stress resistance enzyme activity of ginseng leaves in 4-year-old farmland-cultured ginseng is high,which is suitable for physiological activities of leaves.Under the condition of certain transmittance,with the increase of transmittance,it is beneficial to the accumulation of ginseng polysaccharides.The content of ginsenosides increased first and then decreased with the increase of transmittance.It can be concluded that under the condition of 25-30% transmittance,the accumulation of effective components of ginseng in four year old farmland is beneficial.