Relationship Between The Abortion Of Zingiber Zerumbet And Pollen Germination And Pollen Tube Growth

Zingiber zerumbet is perennial herb in Zingiberaceae,distributed in the global tropical and subtropical regions.Its exotic inflorescence makes it have a high ornamental value.In addition,it can also be used as medicine,food and other effects.Under the natural conditions,It is self-sterility and hybrid sterility so through the massive rhizome for asexual reproduction,and its genetic improvement difficult.C urrently,the study of Z.zerumbet is mainly focused on medical applications,morphological cytology and ecology,and it lacks research in reproductive biology.This study was based on infertile(Z.zerumbet,Z.zerumbet f.variegated)and fertile(Z.nudicarpum)materials were used as materialsv and using pollen in situ germination,pollen in vitro germination,Q uantitative Realtime-PCR and other methods.In order to study the differences between the germination of infertile and fertile materials in pollen in situ germination,pollen in vitro germination and pollen germination and pollen tube growth related genes in Z.zerumbet and Z.nudicarpum.The abortion mechanism of the Z.zerumbet was discussed,which laid the theoretical foundation for the future hybrid breeding of the Z.zerumbet.The main findings are as follows:(1)To study the inoculation of pollen in situ germination and the grows pollen tubes in style and ovary of Z.zerumbet,Z.zerumbet f.variegated and Z.nudicarpum,found that in the Z.zerumbet and Z.zerumbet f.variegated,a small amount of pollen germination on the stigma,only a small amount of pollen tube in the column,and no pollen tube into the ovary.On the contrary,in the Z.nudicarpum,a large number of pollen germination on the stigma,the column also has a large number of normal growth of pollen tube,ovary also has a large number of pollen tubes exist.(2)The Z.zerumbet,Z.zerumbet f.variegated and Z.nudicarpum pollen in vitro germination rate and pollen abnormal rupture rate were determined by sucrose,fructose,glucose,xylose and galactose as sugar sources.The in vitro germination rate of Z.nudicarpum pollen was the highest in sucrose as sugar source,followed by fructose.The Z.zerumbet and Z.zerumbet f.variegated pollen is more germination in glucose,followed by sucrose,other sugar source rarely germination.The abnormal rupture rate of pollen tube in Z.nudicarpum was lower in various sugar sources,and the rupture rate in fructose was the highest,only 2.85%.While the sterile Z.zerumbet and Z.zerumbet f.variegated leaves variant pollen tube abnormal rupture rate is very high,and the rupture rate of Z.zerumbet was 28.5% in fructose and 22.3% in xylose.(3)Sequence analysis shows that the ORF cDN A of MGP2,MGP4 and BUP containned 1422 bp,1092bp and 3036 bp,and encoded 473,363 and 1011 amino acids respectively,and found that MGP2 belongs to the glycosyltransferase 29 superfamily(si-ialyltransferase)members,and MGP4 belongs to the N ucleotide-diphospho-sugar transferase family.The phylogenetic analysis revealed that BUP in Z.zerumbet and UDP-glucuronide transferase in Medicago truncatula to the same subfamily.(4)The temporal and spatial expression patterns of MGP2,MGP4 and BUP in Z.zerumbet and Z.nudicarpum were studied by RT-qPCR.The results showed that MGP2,MGP4 and BUP were expressed in bracts,pollen,leaves,column,germination pollen and petals of Z.zerumbet and Z.nudicarpum.But their expression in the pollen of Z.nudicarpum was 36 times,350 times and 14 times that of Z.zerumbet.MGP2,MGP4 and BUP decreased significantly in Z.nudicarpum,and decreased by 98.3%,97.4% and 80.2% respectively after 2 hours of pollen germination.Indicating that these genes may play an important role in the normal growth of pollen tubes before pollen germination.