Transformation of upland rice with the bar gene and selection for resistance to the herbicide Basta

Abstract

In this study, Chinese upland rice cultivars including Handao297 and Handao502 were transformed with the anti-herbicide bar gene in order to achieve efficient weed control. PCR amplification, Southern blot analysis and field Basta resistance identification in early T 0 , T 1 , and late generation T 6 and T 11 -T 13 illustrated that the exogenous bar gene had been integrated into the genome of the upland rice varieties with stable expression in successive generations. Different transformants had a different gene copy numbers, which was not related to Basta resistance. Some of the transgenic lines showed gene silencing, whereas multiple copies of the bar gene were observed in other late generation transgenic lines. Basta resistance can thus be inherited stably among generations, and an optimal Basta concentration and selective pressure are suitable for resistance segregation and breeding of homozygous progenies with high resistance. After three generations of successive Basta resistance selection in 207 T 0 plants, we obtained 555 T 3 lines. Comprehensive identification and selection for Basta resistance, drought resistance, yield, and other agronomic traits in nine generations yielded two promising transgenic lines, HD297T-31 and HD297T-523. Although both varieties were resistant to 0.1 % Basta, HD297T-31 possessed high (100 %) resistance to Basta while HD297T-523 showed moderate (95 %) resistance. Moreover, during the reproductive stage, the stems, sheaths, leaves, and panicles of HD297T-31 were immune-highly resistant to highly-moderately resistant to 0.5 % Basta, whereas, they were highly resistantmoderately resistant to 1 % Basta. HD297T-523 was immune-highly resistant and immune-highly resistant to 0.5 and 1 % Basta respectively. The plant and stem percentage sensitive to 0.5 % Basta was lower than 1 and 3 % respectively. Since HD297T-31 showed isozygosity, it could be used as a new variety in production.

Application of a novel phosphinothricin N-acetyltransferase (RePAT) gene in developing glufosinate-resistant rice

“…Unfortunately, none of them was verified or applied to the development of transgenic crops. bar has been extensively adopted in developing glufosinate-resistant rice 11 12 13 14 . But it was found that different rice varieties expressing bar showed different levels of glufosinate resistance 11 , which was also reported in transgenic barley with bar 15 .…”

Novel recombinant binary vectors harbouring Basta (bar) gene as a plant selectable marker for genetic transformation of plants

“…This concentration may differ from lab to another according to growth conditions (e.g. Tian et al 2015;Wang et al 2006). Resistant seedlings that were able to produce the second leaf ( Fig.…”

Identification and integrated analysis of glyphosate stress-responsive microRNAs, lncRNAs, and mRNAs in rice using genome-wide high-throughput sequencing

“…The glyphosate stress-responsive genes used for the development of genetically modified crops include EPSPS, glyphosate acetyltransferase (GAT), and glyphosate oxidoreductase (GOX) [8], of which EPSPS is widely used in glyphosate-tolerant rice. Although successful transformation of several glyphosate stress-responsive genes such as OsEPSPS [9], MdEPSPS [10], VvEPSPS [11], G2-aroA [8], G6 [7], AroAJ.sp [12], and I. variabilis-EPSPS [13], have been reported in rice, these transgenic offspring carry exogenous genes. Commercialization of transgenic varieties is greatly hindered, particularly, given the heightened biosafety concerns of transgenic breeding.…”