Facilitated Cultivation,Photoperiod Mutants's Screening And Identification Of Chrysanthemum Indicum Var.aromaticum

Chrysanthemum indicum var.aromaticum is a new variety of Chrysanthemum indicum.It is a new natural aromatic plant for the strong aroma of flowers,leaves and roots.It can be used to extract essential oils or extractum for medicine,drink,cigarette,cosmetics and so on,so it has great development prospect.C.indicum var.aromaticum will face frost before its florescence is over in Heilongjiang.It is not suitable to collect seeds,and it is not conducive to the cultivation and propagation of this plant.In order to make this fine breed widely spread,it is necessary to regulate its florescence.In this experiment,C.indicum var.aromaticum is used as research material to study the effects of floral initiation in different photoperiods(day and night 8/16 h,10/14 h,12/12 h)and different temperatures(16?,20?24?,28?)while it also is used for mutation with Ethyl methane sulfonate(EMS).The results as follows:(1)The progress of floral bud differentiation of C.indicum var.aromaticum can be divided into nine stages including vegetative growth stage;inflorescence primordial differentiation stage;initial stage of involucres primordial differentiation;final stage of involucres differentiation;initial stage of ligulae flower differentiation;final stage of ligulae flower primordial differentiation;initial stage of corolla formation;final stage of corolla formation;finish stage of corolla formation.Short-day treatment could lead to early blossom.Compared with CK,the initial blossom of the three kinds short-day treatments is advanced with 46 d,35 d,30 d,respectively.With the decrease of illumination time,growth indexes such as plant height,the number of leaves,the number of flowers in plant are weakened to varying degrees,but illumination time had little effect on flower diameter.After the treatment of 10/14 h photoperiod,the blossom shows ahead of time.Meanwhile,the plant morphology is well developed and the flowers have high quality.(2)After the 8/16 h,10/14 h and 12/12 h treatment,the leaf chlorophyll contents don't have significant change as the same time the content of soluble sugar and soluble protein changed significantly.With the illumination increased,the content of soluble sugar and soluble protein increased significantly.Soluble sugar and soluble protein are the basis of flower bud differentiation,when the content of soluble sugars and proteins accumulate to a certain degree,photoperiod is one of the main factors affecting bud differentiation of C.indicum var.aromaticum.(3)When C.indicum var.aromatiocum is treated with 16??20??24??28?,its florescence is significant changed.Blossom is the earliest under 24? compared to 16?·20? and 28?.The blossom date is advanced with 7 d,4d and 9 d,respectively.Temperature affect not only the blossom date but also the form growth of plants including the plant height,average intemode length,visible leaf number,stem diameter,and flowers number.However it has a certain adverse effect on the flower diameter of plants.When C.indicum var.aromaticum is treated with 24?,the blossom shows ahead of time.Meanwhile,the plant morphology was well developed and the flowers have high quality.(4)When C.indicum var.aromaticum is treated with 16??20??24??28?,physiological indicators such as the leaf chlorophyll contents,net photosynthetic rate(Pn),stomatal conductance(Gs),transpiration rate(Ci),intercellularCO2 concentration(Tr)are changed significantly.With the temperature increase,each indicator shows a tend of increases first and then decreases.The numerical value of each indicator under the 24? are bigger than other treated temperature.At this treatment,the photosynthetic rate of C.indicum var.aromaticum is the best.(5)C.indicum var.aromaticum is treated with 16??20??24??28?,physiological indicators such as soluble sugar,soluble protein and malondialdehyde were changed significantly.With the temperature increased,the content of soluble sugar and soluble protein in plants increased significantly,and MDA content decreased.(6)C.indicum var.aromaticum mutant library is constructed by EMS mutagenesis.Obtain mutants of florescence,large flowers and other traits.Florescence mutant:When the lighting time is less than 4 hours,plants are not affected by photoperiod.Compared with CK,the florescence of mutants was advanced 17 d and the whole plant height and leaf size are smaller than CK.Larger flower mutant:Plants with abnormal flower diameter are mutagenized by EMS.Compared with CK,the diameter of the mutant flower increased by 28.66%.