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Background: Cercospora leaf spot disease of okra whose pathogen is Cercospora malayensis causes yield losses of up to 60% in plantations. To limit productivity losses, fungicides are commonly used, but are expensive and degrade the environment. Aims: This study aims to test in vitro efficacy of Annona muricata seed extracts against Cercospora malayensis. Study Design: Four extracts were used in this study (the ethyl acetate, acetone, methanol and aqueous extract of A. muricata seeds at the concentrations C1 = 7.5 μl/ml, C2 = 15 μl/ml, C3 = 30 μl/ml and C4 = 60 μl/ml as well as the synthetic fungicide at the concentration of 3.33 g/l) in triplicate. The phytochemical screening of the extracts was performed, the radial growth of pure explants (7 mm diameter) of C. malayensis deposited in sterile Petri dishes containing the PDA medium supplemented with the different concentrations of extracts and incubated at 23 ± 1°C for 6 days were evaluated. Minimum inhibitory concentrations (MIC50, MIC90) were calculated. Results: The extracts of A. muricata seeds are rich in tannins, flavonoids, terpenoids and phenols. The ethyl acetate extract at the concentration C3 resulted in 100% total inhibition of growth of C. malayensis in the Petri dishes. The other extracts resulted in total inhibition of the growth of C. malayensis at C4. The low MIC50 values (12.9 and 21 μl/ml) were obtained with the ethyl acetate and acetone extract, respectively. The ethyl acetate and aqueous extract at the C4 concentration were found to be fungicidal. Conclusion: The extracts were found to be potential fungicide against the C. malayensis strain and might be an alternative in the fight against fungal diseases of okra as their activity was comparable to that of the synthetic fungicide Monchamp 72 WP.

African root and tuber scale (ARTS) Stictococcus vayssierei Richard is a serious constraint to the production of cassava (Manihot esculenta Crantz) in Central Africa, and the food and income security for smallholder farmers. Therefore, to improve the production of cassava it is urgent to determine the appropriate cultural practices that lower ARTS infestation pressure. This study tests the single and combined effects of stem cutting portion and crop variety on ARTS infestation levels’. A split-plot design with four cassava varieties (TMS 96/0023, Excel, Miboutou and Douma) as the main plots and three stem cuttings portions of these varieties (lower, middle and upper portions of the mother plant) as sub-plots was used. The results showed that at 12 months after planting (MAP), lower portions of the local variety Douma showed the highest fresh shoots (2.95 ± 0.13 kg) than the upper portions (2.08 ± 0.09 kg) of the Excel variety. The portions at lower of the Excel variety were the most infested (118-158.38 and 126.75 ARTS) at 3, 6 and 9 MAP respectively. The yield of local variety Douma was higher (20.00-20.11 t ha− 1) in plots planted with portions at middle and lower, followed by yields of TMS 96/0023 variety (19.00 t ha− 1) in plots planted with the lower portions. Overall, irrespective of the cassava variety, the lower portion 16.49 t ha− 1 resulted in higher yield than those the upper portion 10.81 t ha− 1.