Efficacy of Event MON 87460 in drought-tolerant maize hybrids under optimal and managed drought-stress in eastern and southern africa

Caleb O Obunyali; Kiru Pillay; Barbara Meisel; Eric N Ndou; Kingstone Mashingaidze; Julius Pyton Sserumaga; Godfrey Asea; Murenga Mwimali; Regina Tende; Yoseph Beyene; Stephen Mugo; Emmanuel Okogbenin; Sylvester O Oikeh

doi:10.1016/j.jgeb.2024.100352

Efficacy of Event MON 87460 in drought-tolerant maize hybrids under optimal and managed drought-stress in eastern and southern africa

J Genet Eng Biotechnol. 2024 Mar;22(1):100352. doi: 10.1016/j.jgeb.2024.100352. Epub 2024 Feb 1.

Authors

Affiliations

¹ African Agricultural Technology Foundation (AATF), P.O Box 30709, 00100 Nairobi Kenya. Electronic address: C.Obunyali@aatf-africa.org.
² Bayer Crop Science. 27 Wrench Rd, Isando, Johannesburg 1600, South Africa. Electronic address: kiru.pillay@bayer.com.
³ Bayer Crop Science. 27 Wrench Rd, Isando, Johannesburg 1600, South Africa. Electronic address: barbara.meisel@bayer.com.
⁴ Agricultural Research Council (ARC)-Grain Crops Institute Private Bag X1251, Potchefstroom 2520, South Africa; Present address: Bayer Crop Science. 27 Wrench Rd, Isando, Johannesburg, 1600, South Africa. Electronic address: eric.ndou@bayer.com.
⁵ Agricultural Research Council (ARC)-Grain Crops Institute Private Bag X1251, Potchefstroom 2520, South Africa. Electronic address: drkingstone@gmail.com.
⁶ National Agricultural Research Organization, National Livestock Resources Research Institute (NaLIRRI), P.O. Box 5704, Kampala, Uganda. Electronic address: j.serumaga@gmail.com.
⁷ National Agricultural Research Organization, National Crops Resources Research Institute, P.O Box 7084, Kampala, Uganda. Electronic address: grasea9@gmail.com.
⁸ Kenya Agricultural and Livestock Research Organization (KALRO) Agricultural Mechanization Research Institute, P.O. Box 340-90100 Machakos, Kenya. Electronic address: mwimali@yahoo.co.uk.
⁹ Kenya Agricultural and Livestock Research Organization (KALRO) Agricultural Mechanization Research Institute, P.O. Box 340-90100 Machakos, Kenya. Electronic address: itstende@gmail.com.
¹⁰ International Maize and Wheat Improvement Center (CIMMYT), P. O. Box 1041, Village Market, 00621, Nairobi, Kenya. Electronic address: Y.Beyene@cgiar.org.
¹¹ International Maize and Wheat Improvement Center (CIMMYT), P. O. Box 1041, Village Market, 00621, Nairobi, Kenya; Present Address: Center for Resilient Agriculture for Africa (CRA-Africa), PO Box 286-00206 Kiserian, Kenya. Electronic address: mugosn58@gmail.com.
¹² African Agricultural Technology Foundation (AATF), P.O Box 30709, 00100 Nairobi Kenya. Electronic address: E.Okogbenin@aatf-africa.org.
¹³ African Agricultural Technology Foundation (AATF), P.O Box 30709, 00100 Nairobi Kenya. Electronic address: S.Oikeh@aatf-africa.org.

Abstract

Background: Frequent drought events due to climate change have become a major threat to maize (Zea mays L.) production and food security in Africa. Genetic engineering is one of the ways of improving drought tolerance through gene introgression to reduce the impact of drought stress in maize production. This study aimed to evaluate the efficacy of Event MON 87460 (CspB; DroughtGard®) gene in more than 120 conventional drought-tolerant maize hybrids in Kenya, South Africa, and Uganda for 3-6 years under managed drought-stress and optimal conditions and establish any additional yield contribution or yield penalties of the gene in traited hybrids relative to their non-traited isohybrids. Germplasm used in the study were either MON 87460 traited un-adapted (2008-2010), adapted traited DroughtTEGO® (2011-2013) or a mix of both under confined field trials.

Results: Results showed significant yield differences (p < 0.001) among MON 87460 traited and non-traited hybrids across well-watered and managed drought-stress treatments. The gene had positive and significant effect on yield by 36-62% in three hybrids (CML312/CML445; WMA8101/CML445; and CML312/S0125Z) relative to non-traited hybrids under drought, and without significant yield penalty under optimum-moisture conditions in Lutzville, South Africa. Five traited hybrids (WMA2003/WMB4401; CML442/WMB4401; CML489/WMB4401; CML511/CML445; and CML395/WMB4401) had 7-13% significantly higher yield than the non-traited isohybrids out of 34 adapted DroughtTEGO® hybrids with same background genetics in the three countries for ≥ 3 years. The positive effect of MON 87460 was mostly observed under high drought-stress relative to low, moderate, or severe stress levels.

Conclusion: This study showed that MON 87460 transgenic drought tolerant maize hybrids could effectively tolerate drought and shield farmers against severe yield loss due to drought stress. The study signified that development and adoption of transgenic drought tolerant maize hybrids can cushion against farm yield losses due to drought stress as part of an integrated approach in adaptation to climate change effects.

Keywords: CspB gene; DroughtGard®; DroughtTEGO® hybrids; Gene efficacy; MON 87460 Event; Managed drought-stress; Optimum-moisture; Traited transgenic hybrids; Yield penalty; Zea mays.