Evaluating the Success of 3 R-Gene Late Blight Resistant Potatoes in the Diverse Agricultural Landscapes of Asia and Africa (P-29)

Tuesday, July 29, 2025

2:15 PM - 4:00 PM CDT

Location: Ballroom C

Presenting Author(s)

PW

Phillip S. Wharton, PhD

Associate Professor
University of Idaho
Aberdeen, Idaho

Author(s)

EM

Eric Magembe

Researcher
International Potato Center
Nairobi, Nairobi Area, Kenya
IM

Immaculate Makoko

Research Associate
International Potato Center
Nairobi, Nairobi Area, Kenya
MN

Moses Nyongesa

Research Officer
Kenya Agricultural and Livestock Research Organization
Limuru, Nairobi Area, Kenya
MM

Mirium Mbiyu

Research Officer
Kenya Agricultural and Livestock Research Organization
Limuru, Nairobi Area, Kenya
MK

Mahmuda Khatun

Senior Scientific Officer
Bangladesh Agricultural Research Institute
Gazipur, Dhaka, Bangladesh
MG

Marc Ghislain

Research Scientist
International Potato Center
Nairobi, Nairobi Area, Kenya
DD

David S. Douches

Michigan State University
East Lansing, Michigan

The USAID Feed the Future Biotechnology Global Potato Partnership developed bio-engineered potatoes with 3 R-gene late blight resistance. In Asia, the Simplot construct (Rpi-blb2, Rpi-vnt1, and Rpi-mcq1) was inserted into farmer-preferred varieties Granola and Diamant. In Africa, CIP's construct (RB, Rpi-blb2, and Rpi-vnt1) was inserted into Shangi, Tigoni, and Victoria. In 2020 and 2021, confined field trials in Indonesia demonstrated complete late blight resistance in Simplot's Granola and Diamant 3 R-gene lines. The current studies, conducted in Kenya and Bangladesh, assessed the efficacy of these constructs in naturally infected randomized complete block trials late blight trials. In Kenya, 3 R-gene lines (Shangi, Tigoni, and Victoria) were compared to non-transgenic lines at three locations, Muguga, Njabini and Molo. In Bangladesh, Diamant 3 R-gene lines were compared to non-transgenic Diamant at four locations, Gazipur, Rangpur, Chittagong and Munshiganj. Late blight ratings began upon symptom appearance in non-sprayed control plots, continuing weekly until harvest. No late blight was observed in 3 R-gene plots, indicating complete resistance to P. infestans strains in both countries. This data, combined with regulatory information, will be used for the development of dossiers to be submitted to the national biosafety authorities of each country for commercial release of the 3 R-gene potato.