中国农业科学2018，Vol.51Issue(1)：105-118,14.DOI:10.3864/j.issn.0578-1752.2018.01.010
抗除草剂转基因油菜与野芥菜的抗性回交3代子3代的适合度
Fitness of Herbicide-Resistant BC3F4 Between Two Herbicide-Resistant Transgenic Brassica napus and Wild Brassica juncea
摘要
Abstract
[Objective] If herbicide-resistant transgenes escape from transgenic oilseed rape (Brassica napus,AACC,2n=38) to their weedy relatives through pollen flow,weeds with the herbicide-resistant trait might produce new problems for weed control.Wild B.juncea (AABB,2n=36),relative weed of transgenic B.napus,has become a major weed of crop systems across western China,and extended eastward along the Yangtze River valley.In order to provide experimental data for whether the transgene could successfully escape to wild B.juncea,it is necessary to evaluate the fitness of backcross generation between herbicide-resistant transgenic B.napus and wild B.juncea before it is released.[Method] Wild B.juncea and herbicide-resistant BC3mF4R,BC3pF4R and BC3mF4L,BC3pF4L (R and L denote glyphosate-and glufosinate-resistant backcross progeny obtained with glyphosate-and glufosinate-resistant transgenic B.napus,respectively,m and p denote backcross progeny obtained with wild B.juncea as maternal plants and patemal plants,respectively) were planted at low (15 plants per plot) and high density (30 plants per plot) in pure and mixed stands (wild B.juncea:backcross generation were 4 ∶ 1,3 ∶ 2 and 1 ∶ 1).The vegetative components (plant height,stem diameter,the first branch number/plant,above-ground dry biomass/plant) and reproductive components (silique number/plant,total seed weight/plant,silique length,seed number/silique) of these backcross generations were measured.The differences of the composite fitness between BC3F4 and wild B.juncea were analyzed.[Result] Under pure stands,there was no significant difference in the fitness components and composite fitness of BC3F4R with that of wild B.juncea.The composite fitness of BC3F4L was also similar to wild B.juncea although the stem diameter,above-ground dry biomass/plant,and silique number/plant of BC3F4L at high density were significantly lower than that of wild B.juncea.Therefore,either glyphosate-or glufosinate-resistant BC3F4 was as fit as wild B.juncea regardless of density under pure stands.Under mixed stands,at low density,there was no significant difference in composite fitness of glyphosate-or glufosinate-resistant BC3F4 with that of wild B.juncea.At high density,there was no significant difference in fitness components and composite fitness of BC3F4R with that of wild B.juncea regardless planting proportions.However,the plant height,stem diameter,the first branch number/plant,above-ground dry biomass/plant,silique number/plant,total seed weight/plant and composite fitness of BC3F4L were significantly lower than that of wild B.juncea.The correlation analysis showed that the fitness components of BC3F4 were only related to the planting density.[Conclusion] Glyphosate-or glufosinateresistant BC3F4 between glyphosate-or glufosinate-resistant transgenic B.napus and wild B.juncea have a strong survival ability and potential possibility of establishing populations in the field.Moreover,the ecological risk of gene flow is higher from glyphosate-resistant transgenic B.napus than glufosinate-resistant transgenic B.napus.Therefore,preventing gene escape from herbicide-resistant B.napus to wild B.juncea should not only prevent their initial hybrids,but also should prevent the backcross between wild B.juncea and F1 or subsequent generations,so as not to produce higher fitness backcross generation.关键词
抗草甘膦转基因油菜/抗草丁膦转基因油菜/野芥菜/回交后代/适合度Key words
glyphosate-resistant transgenic oilseed rape (Brassica napus)/glufosinate-resistant transgenic oilseed rape (Brassica napus)/wild Brassica juncea/backcross generations/fitness引用本文复制引用
闫静,王晓蕾,张玉池,张庆玲,王建,强胜,宋小玲..抗除草剂转基因油菜与野芥菜的抗性回交3代子3代的适合度[J].中国农业科学,2018,51(1):105-118,14.基金项目
国家转基因生物新品种培育科技重大专项(2016ZX08012005-006)、国家自然科学基金(31270579) （2016ZX08012005-006）
