Pest-Resistance Evaluation And New Variety Screening Of Transgenic Bt Gene Sea Island Cotton (Gossypium Barbadense L.)

Sea Island cotton, as a specific resource of Xinjiang, is more important for the excellent fiber quality and irreplaceable commercial value. In this work, by using the Agrobacterium tumefaciens mediated transformation methord, the Bt gene was introduced into K222, XH25 and XH30. Through PCR detection^ Southern blottug?Bt-CrylAb/lAc strip test and pest-resistance evaluation, it was proved that the Bt gene was integrated and expressed in Sea Island cotton. Then, investigating the agronomic traits, yield traits and fiber quality based on the molecular test. The main results are:(1) The results of PCR showed that nine transgenic cottons all have the target Bt gene and positive rate were above 90%. The results of southern blotting showed that seven transgenic cotton have hybridize stripes; among them three have single copy, three have double copy, one has three copy. Those results indicate that the Bt gene was successfully integrated in Sea-island cottons.(2) Using Bt-Cry 1 Ab/1 Ac strip test to detect transgenic Bt cotton and the contrast, the results showed that transgenic Bt cotton have two amaranth stripes, while the contrast only has one stripe, the positive rate of the K2-ZKC66 achieved 90%.(3) The pest-resistance evaluation showed that the blade of transgenic Bt varieties were lightly damaged and the blade of control was damaged seriously and not full, corrected mortality of seven transgenic Bt cotton was above 60%.(4) The Bt Gene has different impact on the agronomic traits, yield traits and fiber quality the nine Sea Island cottons strains. When using the K222 as recipient, the plant height, start high, initial segment numbers, effective branches, bolls and effective bolls were extremely significant compared with the contrast (P<0.01); there were no significant difference between transgenic and non-transgenic when use the XH25 and XH30 as receptors.(5) The plant height, beginning section height, beginning section number and bolls of the nine transgenic cottons were extremely significant (P<0.01); the effective branches and effective bolls were significant (P<0.05).(6) There were no significant between transgenic and non-transgenic on yield traits; the agronomic traits and yield were significant related.(7) Considering all aspects performance of the 9 transgenic Bt cotton, we screened out three new excellent performance varieties:K2-ZKC66, K2-ZKC31, K2-ZKC70.