Usually the more unlike the parents are the more hybrid vigor is released, but the effect diminishes in subsequent generations as more recessive homozygotes reappear 通常,亲本越不相似,产生的杂种优势越强,但这种优势使下一代的隐性纯合子的出现机率更多。
Their frequencies of gus expression in pollens were 97.755 % 0.800 % and 96.556 % 0.600 % respectively . to verify these results, the self-pollinated progenies of these two putative homozygotes were examined in t2 by histochenmical gus staining of vegetative tissues and pcr analysis using specific primers (2)通过对转基因t1代的花粉gus基因表达检测,快速鉴定和筛选得到了番茄纯合植株,加速了纯合体筛选的进程,证明此方法可靠,而且不会造成大量宝贵材料的浪费。
The characteristics of tm-22 expression presented in transgenic tobacco : 1 ) . virus specificity in either homozygote or heterozygote; 2 ) tm-22 gene integrated in tobacco genomic dna with single copy and in inheritance and segregation to progenies on the mendel role; 3 ) . transgenic line with tm-22 promoter ( ptm47 ) showed infected symptoms with cell death distinguished to one with 35s promoter ( ptm49 ) after inoculation with tomv-2a 其次,通过氨基酸序列和结构的比较,确定tm-2~2基因的编码蛋白与tomv病毒在抗病反应中相互识别的特异氨基酸及其功能;然后,应用重组dna技术,互换tm-2~2基因和tm-2基因的对应结构域,构建嵌合基因,获得嵌合蛋白表达的转化体,验证tm-2~2编码蛋白中变异氨基酸的作用。