Study On Rapid Propagation And In Vitro Flowering Of Tagetes Erecta L.

Tagetes erecta L.are annual plants of Compositae Tagetes L.with big gorgeous flowers,which have long vase life and great filed in the world.At the same time,the flowers can sedate,decrease blood pressure and expand bronchial.The volatile oil also has antibacterial,antimicrobial,antidepressants,insecticidal and other functions.In recent years,more and more researchers extract lutein from Tagetes erecta L.,which is the import raw materials of food,cosmetics,tobacco,medicine and poultry feeds.So it is worthy worldly planting this ornamental plant with great value.But now due to the natural and other condition restrictions,Tagetes erecta L.can not meet the market needs through sowing and cutting.So tissue culture for rapid propagation is necessary. Simultaneously,as living standards improve,people have more and more requests for flowers.In vitro flowers for its new,small were generally accepted.However,fewer species can not meet the needs.It is significant for study Tagetes erecta L.flower in vitro.This paper,by using tissue culture,research rapid propagation,in vitro flowering and internal variation of physiological and biochemical during flower bud differentiation of Tagetes erecta L.,build up systems of intermediate propagation and in vitro flower,decrease the juvenile phases from a vegetative growth to a reproductive growth stage,and inquiry flower bud differentiation regulation.Rapid propagation aspects:this research study the effects of different explants,culture medium,sterilization,6-BA,NAA,Agar,pH and closure film during the induction of different explants of Tagetes erecta L..The mian results were as follows: (1)Stem with axillary bud and terminal bud can easier produce a large number of multiple shoot clumps,which are the best explants.(2)Germination rate of stem with axillary bud is lower when using B5 and White culture medium,highest in using MS.The buds which use MS culture medium grows stronger,and become formations, the MS is favorable to intermediate propagation for Tagetes erecta L..(3)In the selection of sterilization methods of explants,the best effect of sterilization was to deal with HgCl₂ of 0.1%density,9 min-long stem with axillary bud.(4)The different concentration of 6-BA,NAA is very remarkable on the induction rate of stem and leaf, also the effects of different 6-BA and NAA,IAA,2,4-D concentration go together with ratio combination are very different.For the stem with axillary buds,the best medium of rapid reproduction is MS+6-BA0.2mg.L^-1+NAA0.15mg.L^-1,however,for leaf;the best medium is MS+6-BA0.2mg.L^-1+IAA0.05mg.L^-1.(5)The effect of different agar of culture medium is very remarkable on the induction of stem with axillary buds and leaf of Tagetes erecta L.As its agar is 7g.L^-1,the induction rate is highest,bud grow best and grow many leaves.The adventitious buds produced by stem with axillary buds are large 8.2 percent than leaf.(6)The effect of different closure film of culture medium is very remarkable on the induction of stem with axillary buds and leaf of Tagetes erecta L. Through using closure film,the effect on the induction of adventitious buds of Tagetes erecta L.is also significance,results shows that closure film can make bud grow rapidly and become a plant.(7)The effect of different pH of culture medium is very remarkable.No matter stem with axillary buds or leaf,as its pH is 5.8,the induction rate is highest,adventitious bud grow best and grow many leaves.In vitro flowering aspects:This article focuses on the flower bud induction effects of different 6-BA,NAA,sucrose,paclobutrazol(PP₃₃₃),chlormequat(CCC),activated carbon and switching time of Tagetes erecia L..The results show that(1)The different concentration of 6-BA and NAA is very remarkable on the induction rate of flower bud formation,When 6-BA and NAA are combined in level of 0.5mg.L^-1 and 0.1 mg.L^-1,the induction rate of flowering is highest.Add 6-BA alone will inhibit flower formation.The higher the concentration,the stronger the inhibition,and even affect the flower color. (2)When the concentration of activated carbon is 0.3mg.L^-1,the plant don't grow root but induce flower bud.As the concentration reach to 0.Smg.L^-1,there is no flower bud form,but grow roots.(3)When the concentration of sucrose is 40g.L^-1,the induction rate of flower bud is highest.However,with the concentration increase to 50g.L^-1,vitrified shoots were caused slightly.(4)There is diffenence between different switching time.When switching on 15 days,the induction rate of flower bud is highest,30 days reached 32.4 percent and 60 days 58.6 percent.(5)Paclobutrazol can inhibit vegetative growth and promote reproductive gowth of Tagetes erecta L.It also can increase the induction rate of flower bud.When paclobutrazol concentration is 0.4 mg.L^-1,the induction rate of flower bud reach 30.9 percent in 60 days.(6)The appropriate concentration of chlormequat(CCC) for inducing flower bud is 0.5 mg.L^-1,there is 19.7 percent in 60 days.During the flower bud induction,many corresponding physiological and biochemical changes have take place.The results show that(1)In dealing with the early(0～20d),the content of soluble protein increase from 3.390mg.g^-1.FW to 5.718 mg.g^-1.FW,which is 1.308mg.g^-1.FW higher than the content of it in contrast group. (2)In comparision,soluble sugar content was significantly higher than that of soluble protein content.It up to 15.252 mg.g^-1.FW in 30 days,and decrease after.(3)Whether the treatment group or the contrast groups,the content of lutein both increase as time collective.It is highest in 30 days.(4)Regarding to endogenous hormones,IAA content is significantly higher than that of endogenous ABA,and the endogenous IAA content in treatment group is significantly higher than it in contrast group.In 21 days,endogenous IAA content of treatment group reach 17.556nmol.g^-1.FW,7.585 nmol.g^-1.FW higher than that of contrast group.(5)ABA inhibit the seedling growth,the content is significant lower in treatment group,especially in early tissure culture.As the time collection and nutrient gradually consumption,growth rate gradually slow down and flower bud start to differentiat,ABA content gradually increase to reach the largest in 21 days.In all,the contention of soluble proteins,soluble sugar and incretion were higher in control group of high flower bud induction than in treatment group of low flower bud induction. Soluble protein,soluble sugar and the accumulation of lutein provide the necessary material for the flower bud differentiation,endogenous hormones IAA and ABA content show a positive correlation with the flower bud differentiation.