Fermin Gustavo, Inglessis Valentina, Garboza Cesar, Rangel Sairo, Dagert Manuel, Gonsalves Dennis
Department of Biology, Universidad de Los Andes, Mérida, Venezuela.
USDA - Pacific West Area, Pacific Basin Agricultural Research Center, Hilo, HI 96720.
Plant Dis. 2004 May;88(5):516-522. doi: 10.1094/PDIS.2004.88.5.516.
Local varieties of papaya grown in the Andean foothills of Mérida, Venezuela, were transformed independently with the coat protein (CP) gene from two different geographical Papaya ringspot virus (PRSV) isolates, designated VE and LA, via Agrobacterium tumefaciens. The CP genes of both PRSV isolates show 92 and 96% nucleotide and amino acid sequence similarity, respectively. Four PRSV-resistant R0 plants were intercrossed or selfed, and the progenies were tested for resistance against the homologous isolates VE and LA, and the heterologous isolates HA (Hawaii) and TH (Thailand) in greenhouse conditions. Resistance was affected by sequence similarity between the transgenes and the challenge viruses: resistance values were higher for plants challenged with the homologous isolates (92 to 100% similarity) than with the Hawaiian (94% similarity) and, lastly, Thailand isolates (88 to 89% similarity). Our results show that PRSV CP gene effectively protects local varieties of papaya against homologous and heterologous isolates of PRSV.
委内瑞拉梅里达州安第斯山麓种植的当地木瓜品种，通过根癌农杆菌分别用来自两种不同地理来源的番木瓜环斑病毒（PRSV）分离株（命名为VE和LA）的外壳蛋白（CP）基因进行转化。两种PRSV分离株的CP基因分别显示出92%和96%的核苷酸和氨基酸序列相似性。对四株抗PRSV的R0植株进行杂交或自交，并在温室条件下检测其后代对同源分离株VE和LA以及异源分离株HA（夏威夷）和TH（泰国）的抗性。抗性受转基因与挑战病毒之间序列相似性的影响：用同源分离株（92%至100%相似性）挑战的植株的抗性值高于用夏威夷分离株（94%相似性）挑战的植株，最后是泰国分离株（88%至89%相似性）。我们的结果表明，PRSV CP基因能有效保护当地木瓜品种免受PRSV同源和异源分离株的侵害。
