Breeding And Evaluation Of New Cultivars Of Yellow Ground-cover Chrysanthemum For Tea

Breeding and evaluation of new cultivars of yellow tea ground-cover chrysanthemum is of great significance for exerting chrysanthemum’s beautifying,ecological,economic functions and driving farmers to become rich,beautifying urban and rural areas,promoting ecological projects of returning farmland to forests and livelihood projects of poverty alleviation.Ground-cover chrysanthemum is a common ornamental plant of garden cover,which is widely known for its high ornamental value.It is a flower with many functions such as edible,medicinal and drinking.Most of the common tea chrysanthemum cultivars on the market in China are white.At present,there is no new yellow tea ground-cover chrysanthemum Cultivars.It is very necessary to breed the yellow tea ground-cover chrysanthemum cultivars with excellent morphology,color and tea quality.In this study,the ground-cover chrysanthemum cultivar‘TY51’、‘YY3’and several excellent yellow ground-cover chrysanthemum early flower cultivars were used as crossing parents to configure multiple ground-cover chrysanthemum hybrid combinations for artificial hybridization.Then through the evaluation of stress resistance,flowering period,density,plant posture and other comprehensive factors in their offspring,the cultivars of ground-cover chrysanthemum with obvious yellow,early flowering,strong stress resistance and dense flowers were screened out.Then the sensory evaluation and active ingredient content of the dried flowers were comprehensively evaluated,and the yellow tea ground-cover Chrysanthemum Cultivars with good quality were screened out.Finally,a comprehensive evaluation system of the yellow tea ground-cover Chrysanthemum Cultivars in China was established.This paper aims to enrich chrysanthemum cultivars in China and promote the development of tea chrysanthemum production and market.The results are as follows:1.In the breeding experiment of new cultivars of yellow tea ground-cover chrysanthemum,12 cross combinations were set up,1011 seeds were received,271 ground cover chrysanthemum seedlings were obtained.According to the evaluation criteria of percentage system of new cultivars of ground cover chrysanthemum and the breeding objective of this study,22 hybrid plants with the target plant trait of "yellow flower" were preliminarily screened from the plants of hybrid progeny,among which 8 plants with score greater than 75 were selected.Through NY/T5121-2002 Technical Regulations for the Production of Non-Pollution Food-Drinking Chrysanthemum,GB 2762-2017 Limit of Contaminants in Food,NY 659-2003 Limit of Chromium,Cadmium,Mercury,Arsenic and Fluoride in Tea and other standards,a new variety of material‘YZ18’ with the highest score and meeting the national standards was finally screened out.Finally.This cultivar has compact plant type,high degree of uniformity,strong petal double petals,and a large amount of flowers.2.For the selected ground-cover tea chrysanthemum cultivars,three different drying methods were used,namely steaming,shade drying and low-temperature drying,and then the contents of14 active ingredients,such as total flavonoids,chlorogenic acid,tea polyphenols and quercetin,and 10 flavor appearance indicators of tea products,such as dried flower pattern,tea taste and tea fragrance,15 metal elements,16 amino acids,were compared.It was found that eight indexes of vitamin C,organic acid,soluble sugar,soluble protein,monascoside,chlorogenic acid,astragaloside and quercetin in the yellow ground-cover chrysanthemum ’YZ18’ under three processing methods were significantly better than those of the white ground-cover chrysanthemum’TY51’,and 12 of the 16 amino acid indexes tested were significantly better than’TY51’.There are also differences in various indicators under different processing methods,among which the ground-cover chrysanthemum cultivar‘YZ18’has excellent performance,and low-temperature drying has obvious advantages.3.AHP comprehensive evaluation model of ground-cover chrysanthemum was established.Flowering period and yield per mu,sensory evaluation index and chemical composition index were taken as statistical evaluation factors of tea chrysanthemum quality,and the results of weight model were constructed for calculation and analysis.The results showed that low-temperature dried ground cover chrysanthemum’YZ18’had the best comprehensive performance,followed by low-temperature drying’TY51’ 、 shade-dried ground cover chrysanthemum’YZ18’.The comprehensive ranking of 4、5、6 is steamed ground cover chrysanthemum ’YZ18’ 、shade drying’TY51’and steamed’TY51’.Overall,the ground cover chrysanthemum cultivar’YZ18’was superior to the ground cover chrysanthemum cultivar’TY51’.By comparing the three processing methods,it is concluded that low-temperature drying is the best processing method,followed by shade drying,and finally by steaming and drying.