AGRONOMIC TRAITS, GINNING APTITUDE AND JASSID (Amrasca biguttula) TOLERANCE OF COTTON (Gossypium hirsutum. L) VARIETIES IN CAMEROON
Authors: Amma Talba, Abakar Abba Said, Sobda Gonne, Palai Oumarou & Djoulde Darman Roger
Amma Talba: National Advanced School of Engineering. The University of Maroua P. O. Box 46 Maroua, Cameroon.
Abakar Abba Said: The Université of Garoua P. O. Box 346 Garoua, Cameroon.
Sobda Gonne: Agricultural Research Institute for Development, P. O. Box 415 Garoua, Cameroon.
Palai Oumarou: Cotton Development Company, P. O Box 302 Garoua, Cameroon.
Djoulde Darman Roger: National Advanced School of Engineering. The University of Maroua P. O. Box 46 Maroua, Cameroon & The Université of Garoua P. O. Box 346 Garoua, Cameroon.
ABSTRACT
Increasing rainfall variability, growing pest pressure, and strong global market competition highlight the need for high-yielding, resilient, and locally adapted cotton varieties in Cameroon. This study evaluated the agronomic and ginning performance as well as jassid (Amrasca biguttula) tolerance of four newly developed Gossypium hirsutum L. varieties (IRMA L2026, L2033, L2146, L2168) in the Sudano-Sahelian zone. These genotypes were compared with two reference varieties, IRMA Q302 and IRMA A2249, during the 2023/2024 and 2024/2025 rainy seasons across four sites (Sanguéré, Pitoa, Mouda, Kodek) using a Fisher block design with six replications. Agronomic, phenological, and pest-tolerance traits were recorded. The new varieties exhibited good emergence (70%) and plant stand (84.5%) and were generally earlier than the controls, with flowering occurring 56–61 days after sowing and boll opening 107–119 days after sowing. They displayed reduced plant height compared with Q302. Yield performance was encouraging: in 2023, L2146, L2033, and L2026 produced 1.0–2.3 t/ha, while in 2024 all varieties achieved high yields, with A2249 slightly superior (2 t/ha). The new genotypes produced competitive boll weights (4.5 g) and high lint percentages (43–45%), with L2026 showing the highest ginning outturn (45%). Seed indices were similar across genotypes (8 g). Jassid infestation peaked at flowering; L2026 showed the greatest tolerance, yielding 1.2 t/ha without insecticide, whereas L2146 recorded the lowest performance (519 kg/ha). Overall, the four new varieties demonstrated promising productivity, fiber potential, and pest tolerance. L2033 and L2026 appear best suited to the Far North, L2168 to the North, while L2146 shows broader but variable adaptability. Further multilocation trials under semi-operational conditions are recommended to confirm their suitability and refine fiber and seed quality assessments.
Keywords: Cotton variety, Jassids, Agronomic performance, Varietal tolerance, Cameroon’s cotton-growing zone.