Establishment And Optimization Of Cuttings And Tissue Culture Rapid Propagation System Of Rosa Hybrida Minima

Rosa hybrida is one of the most important ornamental plants in the world.It has high ornamental value,economic value and gain the reputation as ’queen in flowers’.Rosa hybrida minima is a special type of modern rose with relatively short and compact shape,Rosa hybrida minima is rich in colors,its leaves and flowers are small and lovely.It has great market demand potential and can be used as valuable breeding resources.At present,extensive studies are needed to optimize the propagation system of cuttage and tissue culture of miniature rose,to simplify the work procedure and improve the work efficiency,and further promote the marketization of the propagation system.Based on the literatures,the establishment and optimization of cuttage propagation system and tissue culture propagation system of five miniature rose cultivars ’Flash Gem’,’Pink Musk’,’Greenland’,’Happy Balcony’ and ’Estoril’ were carried out in this study.The main results are listed as following:1.In order to explore the role of phytohormone on rooting of Rosa hybrida minima cuttage,the different proportions of IBA and NAA solutions were used for quickly dipping of the cuttings of ’joy balcony’.The result showed rapid dipping of cutting in 100 mg·L-1 NAA solution significantly promoted the survival rate of miniature Rose hybrida ’joy balcony’ cuttage,and significantly increased the rooting rate,root number and length of Rose hybrida minima shoots.2.In order to find the cutting substrate that is suitable for the growth of Rosa hybrida minima and improve the survival rate,rooting rate and other indicators of Rosa hybrida minima,different substrates were used for cutting of Rose hybrida ’esteril’ in this study.The experimental results showed that the rooting rate,germination rate,the longest root length,root number and average root length of Rosa hybrida minima cuttings could be significantly increased by the cutting substrate consisted of peat and perlite with a volume ratio of 8:3,and this substrate was also beneficial to the further growth and development of cuttings.After analyzing the physical properties of the cultivation mediums and growth status of cuttings,the results showed the mediums were optimum for cutting growth with bulk density of 1.7-2 g·cm-3,specific gravity of 1.8-2 g·cm-3,and total porosity of 90%-91%,pH value of 6.1-6.6,and electrical conductivity of 0.43-0.45 mS·cm-1.3.In order to optimize the way of large-scale production of Rosa hybrida minima through tissue culture,we designed a variety of different sterilization schemes,and used different rooting,adventitious bud induction and axillary bud germination medium with different hormone combinations to cultivate five varieties of Rosa hybrida minima,respectively.The experimental results showed that the best disinfection method for the stem segments of Rosa hybrida minima is disinfecting the stem segments of Rosa hybrida minima for 5 min with 15%sodium hypochlorite solution;The optimum medium for inducing the axillary bud germination is MS+3.00 mg·L-1 6-BA+0.05 mg·L-1 NAA+1.00mg·L-1 GA3+sucrose 30g·L-1+AGAR 8g·L-1,pH=5.8-6.0.The optimal medium for the induction of adventitious bud proliferation is MS+1.0mg·L-1 6-BA+0.1mg·L-1 NAA+sucrose 30 g·L-1+AGAR 6 g·L-1,pH=5.8-6.0.The optimum rooting medium formulation for Rosa hybrida minima is 1/2 MS+0.50 mg·L-1 IBA+30 g·L-1 sucrose+8 g·L-1 AGAR,pH=5.8-6.0.