Influence of the Beneficial Microorganisms Bioformulations on the Soil Physicochemical Parameters and the Nutritional Profile of Abelmoschus Esculentus Cultivated in Cameroon

Abstract
Abelmoschus esculentus, a plant cultivated in tropical and temperate regions throughout the world, is highly appreciated for its various uses. Its culture encounters difficulties, particularly in Cameroon, due to soil infertility. In order to overcome this difficulty, the use of biological fertilizers in order to regenerate agricultural soils for more production is suggested. Three types of formulations were prepared after in vitro compatibilities tests, T1 (B. amyloliquefaciens and T. harzianum); T2 (B. velezensis and B. amyloliquefaciens) and T3 (B. velezensis and T. harzianum) with the aim of improving soil physicochemical; agromorphological and nutritional profile of okra. The plants were cultivated in 4.5 m² plots, arranged in complete randomized blocks design. ANOVA revealed significant differences between T1treatment and the other treatments and with the T0 control in plant height with the growth rate of 1.144cm/day, fruit length (11.53±0.49cm) and the average weight of fruits per treatment (1868.00±279.45g) at the significance level of P<0.05 (Tukey test). The productivity of treatment T1 per hectare (16.604±2.48t/ha) was highly significant compared to the other treatments and the control (8.53±1.49t/ha). Parameters such as disease resistance, leaf area and number of leaves were not significant between treatments but with the control. The values obtained with T1 treatment were high compared to the others. Regarding nutritional properties, the Na, K, Mg, Cu, Fe, Zn, carbohydrates and proteins contents were significantly increased compared to the control with contents values above the same okra variety. These different results may suggest the use of bioformulation with B. amyloliquefaciens and T. harzianum in order to improve soil fertility and to produce a sufficient quantity and quality of biofortified okra.