Ornamental Evaluation Of Daylilies Varieties And Suitability Of Landscape Application

Hemerocallis is a perennial flower that originated in our country with a cultivation history of nearly 3,000 years.Since the 19 th century,European and American countries have been introduced and cultivated Hemerocallis from China and surrounding areas.Then it has become one of the perennial flowers with rich varieties.Hemerocallis has a strong adaptability,a long flowering period,a large amount of flowers,and a variety of flower patterns and colors,with a great prospect of application in urban and rural beautification and ecological restoration.In the past 20 years,the varieties of Hemerocallis have been gradually enriched through introduction and self-cultivation in China.It is urgent to establish a scientific ornamental evaluation system and a regional landscape application suitability evaluation system.In this study,the ornamental evaluation model for daylilies varieties was established by using AHP(Analytic Hierarchy Process)based on systematic observation and summarizing the ornamental characteristics of daylilies(plant scale)firstly.In addition,60 daylilies varieties with good adaptability and excellent ornamental value were screened out based on the ornamental characteristics data of varieties collected in Shanghai over the past two years.Secondly,a landscape application suitability evaluation system for daylilies varieties was established by using GRA(Grey Relational Analysis)and AHP based on the field observation and the analysis of the landscape application characteristics for daylilies varieties(community scale).And the most suitable varieties were screened from 60 varieties for 8 different landscape application forms(ground cover,flower bed,flower cluster,flower row/flower sea,flower border foreground,flower border middle scene,flower border background and potted plant).Finally,a design for daylilies varieties garden was finished for Smart Ecological Garden in 10 th China Flower Expo through the summarization of domestic and foreign daylilies landscape application cases and field researches.The landscaping techniques and typical configuration patterns of daylilies varieties landscape application were summarized through the design practice in order to provide theoretical basis and reference for the landscape application of daylilies.The main conclusions are:(1)In the ornamental evaluation model of daylilies varieties,experts scored and evaluated 5 criterion-level indicators,and the flower and the adaptability had the largest weights,0.4215 and 0.2212 respectively;among the 17 factor indicators,the factors such as flower color,proportion of flowers above leaves,flower state,disease resistance,and flower spatial distribution have the largest weights;the comprehensive scoring results divide the ornamental quality of daylilies varieties into 4 grades,and the corresponding scores are greater than or equal to 3.5,3.25-3.5,3-3.25 and less than 3.(2)In the landscape application suitability evaluation system for daylilies varieties,experts scored and evaluated the ideal variety characteristics for 8 different landscape application forms.The most important factors for ground cover forms are green period and height,flower volume for flower bed forms,flower state and height or flower cluster forms,proportion of flowers above leaves and flower state for flower row/sea forms,flower state for flower border foreground forms,flower color for flower border middle ground forms,height for flower border background forms and flower spatial distribution for potted forms.(3)Based on the ornamental evaluation model for daylilies varieties,the 60 varieties with excellent ornamental quality in Shanghai area were screened from 117 daylilies varieties,including ’Villa Vanilla’,’Good Impression’,’Big City Eye’,’Bicolor’,’Mini Pearl’,etc.There are the most suitable varieties for different landscape application forms.(4)The landscaping techniques for daylilies varieties in garden applications include height selection,color use,shape and texture matching,and seasonal design.The combination of the most suitable varieties and typical landscaping modes is beneficial to give full play to the ornamental characteristics and garden application value of daylilies varieties.