ICAR-National Research Centre on Plant Biotechnology, Pusa Campus, New Delhi, India.
Department of Bioscience and Biotechnology, Banasthali Vidyapith, Rajasthan, India.
Plant Cell Rep. 2017 Nov;36(11):1747-1755. doi: 10.1007/s00299-017-2189-x. Epub 2017 Sep 13.
This is the first report of stacking two major blast resistance genes in blast susceptible rice variety using co-transformation method to widen the resistance spectrum against different isolates of Magnaporthe oryzae. Single resistance (R-) gene mediated approach for the management of rice blast disease has met with frequent breakdown in resistance response. Besides providing the durable resistance, gene pyramiding or stacking also imparts broad spectrum resistance against plant pathogens, including rice blast. In the present study, we stacked two R-genes; Pi54 and Pi54rh having broad spectrum resistance against multiple isolates of Magnaporthe oryzae (M. oryzae). Both Pi54 and Pi54rh expressed under independent promoters were transferred into the blast susceptible japonica rice Taipei 309 (TP309) using particle gun bombardment method. Functional complementation analysis of stacked transgenic rice lines showed higher level of resistance to a set of highly virulent M. oryzae isolates collected from different rice growing regions. qRT-PCR analysis has shown M. oryzae induced expression of both the R-genes in stacked transgenic lines. The present study also demonstrated the effectiveness of the strategy for rapid single step gene stacking using co-transformation approach to engineer durable resistance against rice blast disease and also this is the first report in which two blast R-genes are stacked together using co-transformation approach. The two-gene-stacked transgenic line developed in this study can be used further to understand the molecular aspects of defense-related pathways vis-a-vis single R-gene containing transgenic lines.
这是首次报道利用共转化方法将两个主要的抗稻瘟病基因堆叠到对稻瘟病敏感的水稻品种中，以拓宽对不同稻瘟病菌分离物的抗性谱。单一抗性（R-）基因介导的方法已被用于管理稻瘟病，但在抗性反应中经常失效。除了提供持久抗性外，基因累加或堆叠还赋予了对植物病原体（包括稻瘟病）的广谱抗性。在本研究中，我们将两个具有广谱抗性的 R 基因 Pi54 和 Pi54rh 转入对多个稻瘟病菌（M. oryzae）分离物具有抗性的感病粳稻品种 Taipei 309（TP309）中。利用粒子枪轰击法将分别在独立启动子下表达的 Pi54 和 Pi54rh 转入到感病的粳稻品种 Taipei 309（TP309）中。对堆叠转基因水稻系的功能互补分析表明，它们对来自不同水稻种植区的一组高毒力稻瘟病菌分离物表现出更高水平的抗性。qRT-PCR 分析表明，这两个 R 基因在堆叠的转基因系中均被稻瘟病菌诱导表达。本研究还证明了使用共转化方法快速进行单步基因累加的策略的有效性，该策略可用于工程持久抗性以对抗稻瘟病，并且这是首次使用共转化方法将两个稻瘟病 R 基因一起进行堆叠的报道。本研究中开发的两基因堆叠的转基因系可进一步用于研究与单 R 基因含有的转基因系相比，防御相关途径的分子方面。
