The Influence Of EMS Treatment On The Rapeseed And The Cloning And Sequence Analysis Of Fad2 Gene

It is very effective way to pormote the producing of the geneticvariaton and creat new plant germplasm by using the physical and chemicalmethod to induce plant gene mutation .This experiment explore the effectsof EMS on period of duration, yield characters and quality characters ofM₁ and M₂ generation by using 0.5%, 1% and 1.5% of EMS to treat the rapeseed(xiang you 15), and mark to the M₂ generation by using SRAP and clonethe high oleic acid mutant Fad2 gene and sequence it. Main results areas follows:1. When the amount of EMS achieves 1.5% and treating time is 6 hours,seed's germination percentage is about 60ï¼…, which is nearly the half fataldose. this amount may be the referenceamount by using EMS to mutate theBrassica napus.2. For M₁ generation, 1% treatment and 1.5% treatment have made changethe characters of the Brassica napus in the M₁ generation, the period ofduration is earlier than the Check, The yeild factor comes under theserious influence, which leads to the decrease of the yeild; As for theentire treatment, the influence is not very abvious about the fatty acidquality in the M₁ generation, but the content of oliec acid of some plantsare higher than 70%, the various characters of 0.5% treatment level arenot obvious difference with the CK. In M₂ generation, the variouscharacters of 0.5% treatment level are not obvious difference with theCK; 1% and 1.5% treatment level also receive the influence in the periodof duration and the yeild character.3. SRAP mark analysis indicated that, the materiales through thetreating of EMS all have the different degree DNA sequence change in threetreatments, comparing with the CK, 1% and 1.5% treatment level has thechange degree to be biggest.4. according to the Fad2 gene (AY577313) sequence of the Brassica napus(Brassica napus AACC=38) in Genebank to design the primers for cloningthe Fad2 of the high oliec acid meterial(oliec acid content 71.5%) thatobtain from the treatment of EMS and the CK(oliec acid content 60ï¼…).Aftersequencing discovered, regardless of the high oleic acid material and theCK, all including two Fad2 genes (label Fad2A and Fad2B). comparing theresults of suqencing by using software DNAstar discovered that thehomology between the Fad2B and the cabbage rape (Brassica campestrisAA=20) is 98.4%, but the homology between the Fad2A and the cabbage rapeis 91.6%. The Fad2 gene turn to 383 through the DNAman sotfware, theresults show that,comparing with the CK, the 614th G basic group turnedC, which causes 205thamino acid D to turn G, namely aspartic acid (Asp)turned glycine (Gly) in the Fad2A of the high oliec acid meterial. In the Fad2B of the high oliec acid meterial, the 59th A basic group turned C,which causes 20th amino acid N to change T, namely asparagus amide (Snp)turned threonine (Thr), and 732th C basic group turned T, which causes241st amino acid Y to change F, namely threonine (Thr) turned cysteine(Cys).