GREENHOUSE AND FIELD EVALUATIONS OF COAT-PROTEIN TRANSGENIC PAPAYA RESISTANT TO PAPAYA RINGSPOT VIRUS

1998 ◽  
pp. 321-328 ◽  
Author(s):  
S. Yeh ◽  
H. Bau ◽  
Y. Cheng ◽  
T. Yu ◽  
J. Yang
Keyword(s):  
Coat Protein ◽  
Ringspot Virus ◽  
Papaya Ringspot Virus ◽  
Transgenic Papaya

scholarly journals Field Evaluation of Transgenic Papaya Lines Carrying the Coat Protein Gene of Papaya ringspot virus in Taiwan

Plant Disease ◽  
2004 ◽  
Vol 88 (6) ◽  
pp. 594-599 ◽  
Author(s):  
Huey-Jiunn Bau ◽  
Ying-Huey Cheng ◽  
Tsong-Ann Yu ◽  
Jiu-Sherng Yang ◽  
Pan-Chi Liou ◽  
...  
Keyword(s):  
Coat Protein ◽  
Transgenic Plants ◽  
Rainy Season ◽  
Field Evaluation ◽  
Weather Conditions ◽  
Fruit Production ◽  
Ringspot Virus ◽  
Papaya Ringspot Virus ◽  
Transgenic Papaya ◽  
Transgenic Lines

Four transgenic papaya lines expressing the coat protein (CP) gene of Papaya ringspot virus (PRSV) were evaluated under field conditions for their reaction to PRSV infection and fruit production in 1996 to 1999. Plants were exposed to natural virus inoculation by aphids in two adjacent fields in four different plantings at the same sites. None of the transgenic lines showed severe symptoms of PRSV whereas control nontransgenic plants were 100% severely infected 3 to 5 months after planting. In the first and second trials, 20 to 30% of the transgenic plants showed mild symptoms consisting of confined mottling or chlorotic spots on leaves. The number of transgenic plants with mild symptoms fluctuated according to the season and weather conditions, with a tendency to increase in the winter or rainy season and decrease in the summer. Also, the incidence of the mild symptoms in the third trial increased significantly due to infection by root rot fungi during the rainy season. Interestingly, there was no apparent adverse effect on fruit yield and quality in transgenic plants with mild symptoms. In the first and second experiments, transgenic lines yielded 10.8 to 11.6 and 54.3 to 56.7 times more marketable fruit, respectively, than controls. All transgenic plants produced fruit of marketable quality with no ringspots or distortion.

scholarly journals Sequences of the coat protein gene from brazilian isolates of Papaya ringspot virus

2002 ◽  
Vol 27 (2) ◽  
pp. 174-180 ◽  
Author(s):  
ROBERTO C. A. LIMA ◽  
MANOEL T. SOUZA JR. ◽  
GILVAN PIO-RIBEIRO ◽  
J. ALBERSIO A. LIMA
Keyword(s):  
Coat Protein ◽  
Carica Papaya ◽  
Protein Gene ◽  
Average Degree ◽  
Ringspot Virus ◽  
Plant Genome ◽  
Papaya Ringspot Virus ◽  
Transgenic Papaya ◽  
Cp Gene ◽  
Worldwide Production

Papaya ringspot virus (PRSV) is the causal agent of the main papaya (Carica papaya) disease in the world. Brazil is currently the world's main papaya grower, responsible for about 40% of the worldwide production. Resistance to PRSV on transgenic plants expressing the PRSV coat protein (cp) gene was shown to be dependent on the sequence homology between the cp transgene expressed in the plant genome and the cp gene from the incoming virus, in an isolate-specific fashion. Therefore, knowledge of the degree of homology among the cp genes from distinct PRSV isolates which are present in a given area is important to guide the development of transgenic papaya for the control of PRSV in that area. The objective of the present study was to assess the degree of homology among the PRSV cp genes of several Brazilian isolates of this virus. Papaya and PRSV are present in many different ecosystems within Brazil. Twelve PRSV isolates, collected in eight different states from four different geographic regions, were used in this study. The sequences of the cp gene from these isolates were compared among themselves and to the gene used to generate transgenic papaya for Brazil. An average degree of homology of 97.3% at the nucleotide sequence was found among the Brazilian isolates. When compared to 27 isolates from outside Brazil in a homology tree, the Brazilian isolates were clustered with Australian, Hawaiian, and Central and North American isolates, with an average degree of homology of 90.7% among them.

Transgene-specific and event-specific molecular markers for characterization of transgenic papaya lines resistant to Papaya ringspot virus

2009 ◽  
Vol 18 (6) ◽  
pp. 971-986 ◽  
Author(s):  
Ming-Jen Fan ◽  
Shu Chen ◽  
Yi-Jung Kung ◽  
Ying-Huey Cheng ◽  
Huey-Jiunn Bau ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Ringspot Virus ◽  
Papaya Ringspot Virus ◽  
Transgenic Papaya

scholarly journals Comparative reactions of recombinant papaya ringspot viruses with chimeric coat protein (CP) genes and wild-type viruses on CP-transgenic papaya

2001 ◽  
Vol 82 (11) ◽  
pp. 2827-2836 ◽  
Author(s):  
Chu-Hui Chiang ◽  
Ju-Jung Wang ◽  
Fuh-Jyh Jan ◽  
Shyi-Dong Yeh ◽  
Dennis Gonsalves
Keyword(s):  
Coat Protein ◽  
Sequence Similarity ◽  
Transcriptional Gene Silencing ◽  
Papaya Ringspot Virus ◽  
Wild Type ◽  
Coding Region ◽  
Transgenic Papaya ◽  
Cp Gene ◽  
Post Transcriptional Gene Silencing

Transgenic papaya cultivars SunUp and Rainbow express the coat protein (CP) gene of the mild mutant of papaya ringspot virus (PRSV) HA. Both cultivars are resistant to PRSV HA and other Hawaii isolates through homology-dependent resistance via post-transcriptional gene silencing. However, Rainbow, which is hemizygous for the CP gene, is susceptible to PRSV isolates from outside Hawaii, while the CP-homozygous SunUp is resistant to most isolates but susceptible to the YK isolate from Taiwan. To investigate the role of CP sequence similarity in overcoming the resistance of Rainbow, PRSV HA recombinants with various CP segments of the YK isolate were constructed and evaluated on Rainbow, SunUp and non-transgenic papaya. Non-transgenic papaya were severely infected by all recombinants, but Rainbow plants developed a variety of symptoms. On Rainbow, a recombinant with the entire CP gene of YK caused severe symptoms, while recombinants with only partial YK CP sequences produced a range of milder symptoms. Interestingly, a recombinant with a YK segment from the 5′ region of the CP gene caused very mild, transient symptoms, whereas recombinants with YK segments from the middle and 3′ parts of the CP gene caused prominent and lasting symptoms. SunUp was resistant to all but two recombinants, which contained the entire CP gene or the central and 3′-end regions of the CP gene and the 3′ non-coding region of YK, and the resulting symptoms were mild. It is concluded that the position of the heterologous sequences in the recombinants influences their pathogenicity on Rainbow.

scholarly journals Engineered Resistance Against Papaya ringspot virus in Venezuelan Transgenic Papayas

Plant Disease ◽  
2004 ◽  
Vol 88 (5) ◽  
pp. 516-522 ◽  
Author(s):  
Gustavo Fermin ◽  
Valentina Inglessis ◽  
Cesar Garboza ◽  
Sairo Rangel ◽  
Manuel Dagert ◽  
...  
Keyword(s):  
Amino Acid ◽  
Agrobacterium Tumefaciens ◽  
Coat Protein ◽  
Amino Acid Sequence ◽  
Sequence Similarity ◽  
Ringspot Virus ◽  
Amino Acid Sequence Similarity ◽  
Papaya Ringspot Virus ◽  
Local Varieties ◽  
Cp Gene

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.

Sign in / Sign up

Export Citation Format

Share Document