The Differences Of Growth Characteristics,fruit Quality And Major Pest Occurrence Frequency Of Six Cultivars Of Lycium Barbarum L. Under Organic Cultivation

Lycii Fructus(goji or wolfberry)is the dried and ripe fruit of Lycium barbarum L.It is a traditional Chinese medicinal herb for both medicine and food,and has the effect of benefiting essence and brightening eyes,nourishing liver and kidney.With people keen on health and food safety awareness,consumers have higher requirements for the quality of wolfberry.Organic wolfberry as the highest standard of wolfberry production,is the direction of high-quality development of the wolfberry industry.However,the organic cultivation of L.barbarum is difficult,and there is no large-scale promotion of planting in China.The first reason is that there are many kinds of pests on L.barbarum and difficult to control.The second is that L.barbarum is a plant with a large demand for fertilizer but the organic planting land is usually barren.As a result,the cost of organic wolfberry production is high but the benefit is low.Selecting good cultivars is the premise of efficient production,so it is necessary to screen the cultivars with excellent yield,high resistance and high quality suitable for organic production,so as to promote the healthy development of organic wolfberry industry.The 6 cultivars of L.barbarum Ningqi-1,Ningqi-4,Ningqi5,Ningqi-7,L.barbarum strain 0909 and Qixin-1 were planted in Xiaoyanchi Village,Zhongning County,Ningxia province,in the same plot,and all the cultivars were planted according to Chinese organic standards and managed uniformly(GB/T 19630—2019).The phenology period,biomass,fruit traits,yield,population number and dynamics of 6 major pests of L.barbarum community,etc.were investigated,and the content of L.barbarum polysaccharide(LBP)of Lycii Fructus were measured.The main research results are as follows:1.Comparing the growth and development rules of the 6 cultivars of L.barbarum in Zhongning County,Ningxia province,the high-yielding cultivars Ningqi-1,Ningqi-4 and Ningqi-7 under organic planting conditions were screened out.In the production area of L.barbarum in Ningxia province,Ningqi-1 and Ningqi-4 had late phenological stage,not excessive vegetative growth,large flowering amount of last year’s branches,high setting rate,strong branch formation ability,high and stable yield,and it is most suitable for largescale organic planting.Ningqi-7 had early germination,strong vegetative growth,strong continuous fruiting ability,and high fruit yield in summer,and it is also suitable for organic cultivation.Ningqi-5 had the earliest phenological stage,long growth cycle,and the most vigorous vegetative growth.Due to pollen abortion,fruit set rate was often affected by weather.Therefore,the allocation of pollinating trees should be fully considered in organic planting to achieve high yield.Qixin-1 had strong vegetative growth but weak natural branch formation ability,which required pruning for several times to promote reproductive growth and achieve high yield.The vegetative and reproductive growth performance of L.barbarum strain 0909 was poor,which was not suitable for organic cultivation.2.The population number and dynamics of major pests of the 6 cultivars of L.barbarum were analyzed.the results showed that Ningqi-1 and Ningqi-4 were less infested with the pests under organic planting conditions.Pest populations on Ningqi-1 and Ningqi4 were less,while populations on Ningqi-5,Ningqi-7,L.barbarum strain 0909 and Qixin1 were more.The growth of L.barbarum were correlated with the pest’s occurrence.the leaf pests(Aceria pallida)of L.barbarum were positively correlated with vegetative growth,while the flower pests(Gephyraulus lycantha)of were positively correlated with reproductive growth.3.The basic characteristics of fruits and the content of L.barbarum polysaccharide and betaine of 6 cultivars were compared.Although the quality of different cultivar is different,it can meet the requirements of Chinese pharmacopoeia under organic planting conditions.Ningqi-5 had large fruit,high sweetness,the highest average content of LBP(13.29%),and the content of LBP changed little during the harvest period.Ningqi-7 has large fruit,higher LBP content.L.barbarum strain 0909 has highest average betaine content(0.66%).Qixin-1 had larger fruit,higher average contents of LBP and betaine,the content of LBP changed more during the harvest period.Ningqi-1 and Ningqi-4 fruits were small,low average content of LBP and betaine,and the content of LBP was stable during the harvest period.To sum up,Ningqi-1 and Ningqi-4 had the second highest yield and less pests.Ningqi7 had good plant growth,high yield and quality.Ningqi-5 grows vigorously with large fruit but has severe A.pallida and low yield.Qixin-1 had vigorous growth with large fruit,but it requires high pruning management,so it did not obtain high yield during experiment period.L.barbarum strain 0909 is weak growth,low yield,and more serious pest damage.In conclusions,for large-scale organic wolfberry production in Ningxia province,Ningqi-1,Ningqi-4 and Ningqi-7 should be given priority.