Evaluation of Seven Phenoxyacetic Acid Drifts on Morphological Parameters of Three Rice (Oryza sativa L.) Varieties under Controlled Sowing Conditions in Côte d'Ivoire

Rice, the main food of the population in Côte d'Ivoire, has a low yield. This study aimed to evaluate the ability of phenoxyacetic acid derivatives to boost the vegetative parameters of rice was conducted in Azaguié using a split-plot design. The rice varieties WA638-1, C26, Nérica 2 and seven phenoxyacetic acid derivatives were used. Three rice seeds of each variety were sown in pots. One seedling per variety was de-mated at 7 DAS. Volumes of 150, 180, and 225 ml concentrated at 10-5 M, 10-7 M, and 10-9 M were applied to the leaves on 15, 20, and 25 DAS, respectively. Height, number of tillers, girth and vigor index were determined. The results showed that treatment T7 improved the height of WAB638-1 to 6.75% and tillering to 366.6%. The vigor index was increased to 9.52% by T8 treatment and girth to 80.37% by T20. The formation of C26 tillers was favored at 171% by the T7 treatment, the girth at 83.17% by T21, the vigor index at 10 % by T21 and at 7.50% by the T14 and T8 treatments. In Nérica 2, vigor index and girth were positively induced at 15.15% and 34.83 % by T19 respectively. The vigor index was also promoted at 12.12% by treatments T20 and T21 and the number of tillers was improved at 150% by T13 and T19. As for height, it was stimulated to 22.39 % by the T14 treatment. The height of C26 was reduced except for T12, the vigor index was decreased to 2.50% by treatments T15, T17 and T3, the tillering to 66.70% by T4. The height of WAB638-1 was inhibited to 2.56% with T1 treatments. Treatments T13, T14, T7, T8, T19 and T20 were those that improved the observed parameters.