JGG 2002, 29(11): 1005-1011 DOI:   ISSN: 1673-8527 CN: 11-5450/R           

Current Issue | Archive | Search in JGG                                                            [Print]   [Close]
Article  

Studies on the Distorted Segregation of Foreign Genes in Transgenic Rice Progenies

XIE Xiao-Bo; CUI Hai-Rui;SHEN Sheng-Quan; WU Dian-Xing; XIA Ying-Wu; SHU Qing-Yao

Laboratroy of Mutation Genetics and Plant Molecular Improvement,Institute of Nuclear Agricultural Science, Zhejiang University,Hangzhou 310029,China

Abstract

The segregation mode of transgenes was investigated in the transgenic progenies of three rice varieties (lines) produced by Agrobacterium-mediated transformation. The transgenic lines all contained the Bacillus thuringiensis cry1Ab gene, under the control of a maize ubiquitin promoter, and linked in tandem with gusA and hpt genes. PCR analysis showed the transgenes cry1Ab and gusA co-segregated in all selfed and crossed progenies tested. Therefore, GUS bio-assay of leaf or endosperm tissues was used to monitor transgene segregation in the experiment. It was found that the ratio of positive to negative plants was significantly smaller than 3:1 in all heterozygous plants derived progenies, which implied the segregation biased from typical Mendelian mode for a single dominant gene. Less GUS positive plants, and consequently less homozygous transgenic lines than expected were recovered from the selfed progenies. Transgenic heterozygous plants (+ / -) were crossed as female or male parent to conventional rice varieties (-/-), and the ratio of gusA positive (+ / -) to negative (- / -) plants was investigated in test F1 population. When used as female parent, the segregation fit ro 1:1, but significantly smaller than 1:1 when used as male parent. The used-set of transgenic Nipponbare progeny was investigated individually for GUS positive and negative plants. It was found that the positive plants had an average seed-set of 64.5%, significantly lower than that of negative plants (77.9%). The biological and genetic basis of distorted segregation of transgenes was discussed and deduced on the basis of above results, and the anthors are inclind to ascribe these phenomena to the poor competitive ability of pollens carrying transgenes.

Keywords transgenes   distorted segregation   pollen   rice  
Received 1900-01-01 Revised 1900-01-01 Online 2002-11-10 
DOI:
Fund:
Corresponding Authors:
Email:
About author:

References:
Similar articles

Copyright by JGG