AMMI, GGE, and multi-trait stability analyses identify peanut genotypes combining yield stability and reduced aflatoxin B1 accumulation under terminal drought in Cameroon

Abstract

Peanut (Arachis hypogaea L.) yield stability and aflatoxin B1 (AFB1) contamination are critical determinants of food and nutritional security in sub-Saharan Africa, where the crop is widely grown under marginal, drought-prone conditions. This study evaluated genotype × environment (G×E) interactions for yield-related traits and AFB1 accumulation in eight peanut genotypes (55–437, 57–313, 73 − 33, Manipintar, Fleur 11, Grimari, Peau lisse, Siksa) across four environments in Cameroon, combining two locations (Bafia and Dschang) with two moisture regimes (normal rainfall and terminal drought stress) in a randomized complete block design. Total biomass, pod number, hundred-seed weight, dry matter, dry yield, and AFB1 concentration were analyzed using combined ANOVA, the AMMI and GGE models, Best Linear Unbiased Prediction (BLUP), and the Multi-Trait Stability Index (MTSI). Combined ANOVA revealed significant (p < 0.05) genotype, environment, and G×E effects for all traits, with environment explaining the largest share of variation for AFB1 content (43.6% of the sum of squares) and genotype explaining the largest share for hundred-seed weight (52.4%). Based on weighted average of absolute BLUP scores (WAASB), genotypes Grimari, 55–437, Fleur 11, and Peau-lisse combined the lowest and most stable AFB1 contamination, while Grimari, 57–313, and Siksa combined high and stable dry yield. The MTSI identified Grimari as the ideal multi-trait genotype, combining acceptable yield potential (2.5 t.ha− 1) with the lowest, most stable AFB1 levels, and is proposed as a promising candidate for further multi-year, multi-location validation toward climate-resilient, safer peanut varieties for Cameroonian smallholders. However, all genotypes exceeded the EU regulatory limit for aflatoxin B1 in groundnuts intended for direct human consumption (2 µg.kg− 1; Regulation (EC) No 1881/2006, as amended by Regulation (EU) No 165/2010), indicating that genetic selection alone is insufficient and must be combined with integrated pre- and post-harvest aflatoxin management in smallholder systems across sub-Saharan Africa.