Study On The Breeding Potential Of Chinese Dendrobium

The research on genetic information of crossbreeding parents plays a guiding role in crossbreeding.This dissertion intends to find out more inheritance rules of Dendrobium by combining with pedigree analysis.79 Chinese Dendrobium native species and 33 excellent Dendrobium hybrids from TOGA are used as experimental materials.Firstly,all the genetic background of materials are clarified through pedigree retrieval.Secondly,on the basis of first part,11 ornamental plants of Dendrobium were chosen in the pollination experiment,which belong to sects.Callista and Latouria.There are 36 hybridized combinations’ seed setting rates being evaluated throgh the experiment.The main results are shown as follows:1.Section is used as a taxa.Among 79 Chinese Dendrobium native species which belong to 12 sections,there are 47 species from 12 secions existing hybrid login record.It is easier for sect.Dendrobium and sect.Formosae to produce offsprings by hybridization in sections.Conversely,it is easier for sect.Breviflores,sect.Callista,sect.Distichophyllum,sects.Holochrysa and Pedilonum to produce offsprings by hybridization between sections.Sect.Breviflores can crossbreeded with sect.Calcarifera.Sect.Callista can crossbreeded with sects.Calcarifera,Dendrobium,Formosae,Holochrysa,Latouria,Phalaenanthe and Spatulata.Sect.Dendrobium can crossbreeded with sects.Breviflores,Callista,Calcarifera,Calyptrochilus,Formosae,Holochrysa,Latouria,Phalaenanthe and Spatulata.Sect.Distichophyllum can crossbreeded with sect.Formosae.Sect.Formosae can crossbreeded with sects.Calcarifera,Dendrobium,Latouria,Phalaenanthe and Spatulata.Sect.Holochrysa can crossbreeded with sects.Calcarifera,Dendrobium,Formosae,Latouria,Phalaenanthe and Spatulata.Sect.Pedilonum can crossbreeded with sects.Calcarifera,Calyptrochilus and Cuthbertsonia.Sect.Stachyobium can crossbreeded with sects.Phalaenanthe and Spatulata.Sects.Callista,Formosae,Dendrobium and Holochrysa are the main breeding material,and the breeding potential of sects.Distichophyllum,Pedilonum and Stachyobium are getting more and more attention.2.Based on the order of ranking and grade of TOGA from 2003 to 2015,33 rewarded Dendrobium hybrids are chosen to be experimental materials.The study shows that the breeding histories of 33 excellent hybrids involve 60 native species,respectively belongs to sect.Pedilonum,sect.Calyptrochilus,sect.Formosae,sect.Dendrobium,sect.Phalaenanthe,sect.Spatulata,sect.Latouria and sect.Dendrocoryne.The quantity of excellent in-section crossed Dendrobium hybrids is as much as the quantity of excellent between-section crossed ones.Sect.Formosae holds the biggest share between in-section crossed hybrids,and sects.Phalaenanthe and Spatulata hold the biggest share in between-section crossed hybrids.With the increasing of hybridization times of Dendrobium or more excellent native species involved in the history of hybridization,genetic diversity will be reduced.3.Taking advantage of academic greenhouse,11 ornamental plants of Dendrobium are used as hybridized materials,which from sects.Callista and Latouria.Interrelated analyses conclude that the seed setting rate of hybridization between sects.Callista and Latouria is as low as 6.6%.Den.chrysotoxum and Den.lindleyi lead to low seed setting rates when they used as female parents in hybridization.The seed setting rates of Den.Frank Thall × Den.lindleyi,Den.Misty Rose × Den.lindleyi,Den.Frank Thall × Den.chrysotoxum,Den.Misty Rose × Den.chrysotoxum are significantly higher than other hybrid combinations.It is speculated that the ancestry of sect.Phalaenanthe enhance the seed setting rates of sects.Callista and Latouria.