Effects Of Exogenous Hormones On The Growth And Development Of Lily Bulbils

Lily germplasm resources in China are abundant,however,the popular varieties in the market are cultivated abroad,The bulbs rely on imports,and the breeding technology is backward.Bulbs degradation is the bottleneck that restricts the development of lily industry in China,In order to realize the domestication of bulbs,it is necessary to explore the regularity,physiology,biochemistry and related molecular mechanisms of the occurrence and propagation of lily bulbs.Reproductive method includes seed propagation,scale cutting,bulbil propagation,and tissue culture.bulbil propagation that is an excellent method for lily bulb propagation,shortens the growth cycle,has a high degree of homogenization,and the advantages of high survival rate,high yield,and low toxicity rate.In this study,the histological and morphological observations were carried out to study the development process of Lilium bulbil.In order to determine the dynamic changes of endogenous hormones during the formation of the bulbil,the endogenous hormone content was determined by ELISA.Spraying the exogenous GR-24 and Tis-108 solution,IAA and NPA solution at the leaf axil to establish a method for regulating lily bulbils.Main research results is obtained as follows:(1)The bulbils is produced in the near axial surface of the base of the young petioles,and the internal cells is relatively small.The growth rate of the outer scales of the bulbils is faster,the scales is cracked,there is a formed bulbil structure,and the developing bulbils don’t have obvious root structure differentiation.(2)The contents of ABA,iPA and JA-me decreased,and the ratios of ABA/GA3 and ABA/GA4 decreased,which promoted the sprouting of bulblets;the contents of ABA and IAA increased,and high levels of IAA/iPA,IAA/GA3 and IAA/GA4 promoted bulb bud enlargement.When the shoots are mature,the ZR content is the lowest,and high levels of ABA/IAA,ABA/ZR promote bud ripening.(3)GR-24 treatment delays the occurrence of bulbils,Tis-108 treatment promotes the growth and development of bulbils,IAA treatment promotes the development of bulbils,NPA treatment significantly inhibits the occurrence of bulbils.In view of the present situation of Chinese Lily seed industry,this study explored the physiological and biochemical mechanism of the hormonal signal response to the occurrence and morphogenesis of the bulbils,and provided a theoretical basis for the analysis of the molecular mechanism and related regulatory genes of lily bulbils,and provided support for the production of lily bulbils.