Cocoa black pod disease caused by Phytophthora megakarya and reduced soil fertility are major constraints to cocoa production resulting in high yield losses. In the absence of effective control measures and constraints related to the use of chemical fungicides and fertilizers, there is a need to develop additional and sustainable disease and fertilization management strategies. With the lack of studies related to the use of compost in cocoa cultivation, the present study aims to evaluate the potential of cocoa pod husk (CPH)-based compost as a soil amendment to reduce the severity of cocoa black pod disease and enhance plant growth. In vitro antagonism test showed that compost water extracts (CWE) reduced mycelial growth with inhibition rate reaching 100% associated with microorganisms. Disease score of cocoa plantlets grown on compost-amended soils significantly reduced compared to plantlets grown on non-amended soil (control). All compost rates tested significantly increased populations of actinomycetes and fungi and biological activity in the soil. Compost application increased soil pH and majority of the essential elements but decreased Al content, which is toxic to cocoa growth in acidic soils. Soil application of compost at the dose of 20% (v/v) significantly increased stem length and number of leaves compared to the control. This study shows that CPH-based compost can not only improve soil fertility and cocoa growth but also reduce cocoa black pod disease severity by direct effects on inoculums level in the soil and by inducing resistance in the plant.

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Several ingredients are often introduced into rubber matrices during the production of natural rubber (NR) based articles, essentially to modify and improve upon the properties of the final products as well as to reduce their costs. In this study, composites of natural rubber and cocoa pod husk were prepared by solution casting and tested for their rheological and thermal properties in order to ascertain the suitability of the latter as a substitute for standard fillers in the NR industry. An increase in the level of substitution significantly reduced the rheological properties of the composites in the linear viscoelastic region but had no significant effects on their thermal stability, glass transition temperature and on the α‐relaxation of the NR composites except at the highest level of substitution (25%). However, α‐relaxation and rheological shift factors were always temperature‐dependent and had a direct influence on their electrical conductivity with no permanent chemical bonds formed or broken during preparation of the composites. Hence, untreated cocoa pod husk could serve as non‐reinforcing filler for raw natural rubber.

Polymers contain extraordinary qualities, such as self-healing. Research and development of this form of polymer, which regenerates after injury, is an essential asset for artificial material lifetime and environmental sustainability. These polymers produced through polar interactions, hydrogen bonds, disulfide bonds, Diels Alders reactions and other types of interactions can totally recover their original qualities (high self healing effectiveness) at the molecular scale with repeatability without the need of chemicals. Self-healing capabilities may be introduced into a wide range of different materials, including concrete, ceramics, and metals, in addition to polymers and their composites. Despite extensive research in this field, mastering the self healing mechanism (intrinsic and extrinsic), characterization (spectroscopy and microscopy such as SEM, TEM to provide evidence of healing), and finding new sources of crosslinked fillers for polymers composites with high intrinsic self healing capabilities remain a significant difficulty. Microscope in the realm of creative product development, self-healing polymers and rubber composites have produced outstanding outcomes. Because of their exceptional excellent properties, such as strength/weight ratio, these materials have achieved great outcomes as well as corrosion resistance, fatigue resistance, specific heat resistance, specific modulus, high self healing capability. This article briefly reviews some important point of the mechanism, characterization, application and recent accomplishments of great self healing ability of rubber composites.

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