Evaluation of selected transgenic papaya (Carica papaya L.) lines for inheritance of resistance to papaya ringspot virus and horticultural traits

Abstract

Three selected transgenic papaya lines 124-3, 132-2 and 142-3 across the T 1 and T 2 generations were preliminarily evaluated under Biological Containment Level 2 (BL2) greenhouse approved by the National Committee on Biosafety of the Philippines (NCBP) to determine the partial stability of expression of resistance to papaya ringspot virus (PRSV) and selected phenotypic traits. e PRSV reaction of the three transgenic lines using mechanical inoculation test and enzyme-linked immunosorbent assay was assessed. e qualitative and quantitative horticultural traits at owering and ripe fruit stages of the transgenic lines were also evaluated. Based from preliminary results, the percentages of resistant progenies to PRSV in the T 1 generation were 83% for 124-3, 74% for 132-2, and 70% for 142-3. However, in the same generation, no di erence between the transgenic and non-transgenic were observed for stem, leaf and petiole color, fruit shape, peel, esh and seed color, stem diameter, number of days to rst ower, and fruit edible portion, indicating that the transgenic is seemingly stable. e percentage of resistant progenies to PRSV in the T 1 generation decreased in the T 2 generation, indicating that the inherited resistance of the three transgenic lines was unstable, and a continuous evaluation of the transgene could be done in later generations. In contrast, the light green (RHS 141B) stem color, dark green (RHS 141A) leaves and petioles and creamy white owers (RHS 155A) were stably expressed in both the T 1 and T 2 generations. e plant height for lines 124-3 and 142-3, internode length for line 142-3 and number of nodes to rst ower for lines 132-2 and 142-3 were also stable in both T 1 and T 2 generations. In addition, the pyriform fruit shape for hermaphrodite sex form and rounded fruit shape for the female sex form, light yellow orange (RHS 17A) peel color, bright yellow orange (RHS 23A) esh color and black (RHS 202A) seeds of the three transgenic lines were stably expressed in both generations. e fruit weight, total soluble solids and fruit edible portion for lines 124-3 and 142-3 was stably expressed in both generations.

Gene Technology for Papaya Ringspot Virus Disease Management

“…The “green” or unripe fruits can be used as vegetables. Papaya is also utilized in the pharmaceutical and cosmetics industries [ 5 ].…”

Research status of the development of genetically modified papaya (Carica papaya L.) and its biosafety assessment

“…전세계 파파야 산업에서 가장 문제가 되는 것은 papaya ring spot virus (PRSV)이다. 이 바이러스는 진딧물이나 감염 된 종자에 의해 전이되며 과실에 둥근 반점이 나타나고 잎에 도 영향을 미쳐서 생산량과 품질을 크게 떨어뜨리는 것으로 알려져 있다 (Purcifull et al 1984;Tomas and Dodaman 1993;Tennant et al 2007;Retuta et al 2012). 이 바이러스는 파파야에 서 아직까지도 효과적인 방제방법이 없기 때문에 파파야를 재배하는 국가에서는 형질전환기술을 이용한 저항성 품종 개발 등 다양한 연구가 이루어지고 있다 (Gonsalves 1998;Teixeia da Silva et al 2007;Fermin et al 2010 (Litz and Conover 1982;Fitch and Manshardt 1990), 이를 바탕으로 한 형질전환 체계의 확립을 통해 PRSV에 저항성을 갖는 GM 파파야 품종 ('SunUp', 'Rainbow' 등)의 상업화가 가능하게 되었다 (Gonsalves 1998 Mahon et al 1996).…”