## 1 Introduction  
_Panax ginseng_ C.A. [PERSON] is a perennial herb that grows slowly [1], and has a long history of medicinal use in traditional Chinese medicine. Ginseng has numerous pharmacological effects on humans, including acting against tumors, as an antioxidant, to inhibit fat accumulation [2; 3; 4], improving immunity, improving erectile function, and to help combat cardiovascular and cerebrovascular disease [5; 6; 7; 8; 9; 10; 11]. These benefits come with few adverse reactions or side effects. According to the skeleton of aglycones, ginensoides have been classified into two major types: dammarane and oleanane [12]. The dammarane-type ginensoides contain two groups: protopanaxadiol (PPD) and protopanaxatriol (PPT) [13]. Ginseng grows very slowly and needs at least 5-6 years cultivation to be used in a medical clinic. Thus, it is widely accepted that the longer the ginseng grows, the better quality it is, with many previous studies reporting how the amount of total accumulated ginensoides increases continuously with the duration of cultivation [14]. Analytical data on the accumulation and variation of ginensosidelevels in different tissues cultured at different growth stages, and the correlation between ecological factors and synthetic key enzyme gene expression are still missing. Environmental factors affect the distribution, growth, yield, and quality of ginseng production areas. Ginseng medicinal materials have obvious local characteristics. Different ecological factors cause differences in the quality of the genuine regional drug. Ginseng grows best under some degree of shading. Shading of 20% is beneficial to the accumulation of ginsenoside content in ginseng roots, while 15% shading has been found to be beneficial for the accumulation of ginsenosides in the leaves of _Panax ginseng_[15; 16]. A relative soil water content of 60-80% can promote the growth of ginseng; however, if the water content of the soil is too high, this can result in root decay due to lack of air in the soil pores. The relative humidity of the air affects plant growth via its effect on transpiration in the leaves [17; 18]. At 400-600 m altitude, the ginsenoside content of plants increases with elevation above sea level. Ginseng volatile oil content varies greatly at different altitudes, but also generally increases with altitude [19]. In recent years, the ginsenoside biosynthesis pathway has been gradually clarified [20]. The biosynthesis pathway of ginsenosides is divided into two parts, upstream and downstream: (1) acetyl-CoA undergoes the action of mevalonate (MVA) to form 3-isoprene pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), then IPP and DMAPP are catalyzed by various enzymes to form 2,3-oxidosqualene; (2) 2,3-oxidosqualene is cyclized, hydroxylated, and glycosylated, and structural modification is used to synthesize various monomeric ginsenosides, among which the key enzyme is the first in the MVA pathway in plants regulating ginsenoside synthesis is 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) [21]. A rate-limiting enzyme affects the production of isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP); farnesyl diphosphate synthase (FPS) [22] catalyzes the formation of farnesyl pyrophosphate (FPP) by IPP and geranyl pyrophosphate (GPP); squalene synthase (SS) [23] is involved in the catalytic synthesis of squalene; squalene epoxidase (SE) [24] catalyzes the formation of 2,3-oxidized squalene; dammarendiol synthase (DS) [25], and \(\beta\)-amyrin synthase (\(\beta\)-AS) [26] catalyze the formation of 2,3-oxidized squalene--a precursor of an alkane type, oleanane type ginsenoside--and finally, cytochrome P450 (CYP450) and glycosyl transferase (GT) undergo carbocyclic modification and glycosylation modification, and they exist in a plant in the form of a supergene family. This allows the formation of complex and diverse monomeric ginsenosides, and currently functionally verified genes such as CYP716A47 [27], CYP716A52v2 [28], and CYP716A53v2 [29].