The rainfall disturbances observed in the recent decades in Côte d'Ivoire constitute a constraint for sustainable cocoa production, the mainstay of the Ivorian economy. These disturbances constitute, in addition to the losses of production and those from the quality of the cocoa beans, one of the causes of the high cocoa mortality at the recovery stage in all cocoa production area. The present study, carried out in the Goh and Lôh Djiboua, post-pioneer regions, is a contribution for the searching of solutions to the continuity challenge of the Ivorian cocoa farming in front of the climate change. It aims to analyze not only the evolution and distribution of rainfall, but also to identify the rainfall constraints related to cocoa farming, and to propose possible solutions to ensure the sustainability of cocoa farming in these two regions. The analysis covered the three decades of the period from 1986 to 2015. The rainfall data were collected at the weather stations of the CNRA (Centre National de Recherche Agronomique) based both on Divo and Gagnoa. The study of the two rainfall data series using the rainfall index showed that the current climate of the two regions is characterized by a predominance of dry periods at Divo and the wet one in Gagnoa. Also, 40 to 90% of the 30-years recorded less than 700 mm of rain during the main rainy season both in the two regions. In addition the beginning of the rainy season in the two regions is between the 1st and 2nd 10 days of March in both regions, while in practice the planting of cacao is usually made in May or June. To note this variability, the technical itineraries for all regions must to be regionalized to enable cocoa to exhibit its potentialities in its new production environment.

Black pod rot is one of the most widespread diseases in the species Theobroma cacao L. In Côte d'Ivoire, it causes significant yield losses, estimated at about 10 to 60% depending on the ecological zones. This study was conducted in order to identify Phytophthora spp isolates in the cocoa orchard by the analysis of their molecular features and assess their pathogenicity on cocoa tree leaf disks having different sensitivity. Thirty-six isolates of Phytophthora spp., from 06 producing regions (Divo, Soubré, Daloa, Duékoué, Abengourou and Aboisso) were taken from immature pods naturally affected by black pod rot. Methods of molecular analysis based on PCR-RFLP techniques, sequencing the ITS1 region of ribosomal DNA and artificial inoculation tests on cocoa tree leaf disks were used to identify Phytophthora isolates and assess their aggressiveness. The results obtained enabled to identify Phytophthora palmivora and showed a difference of aggressiveness between isolates of this species with average grades of foliar sensitivity ranging from 0.90 to 3.93.

Cocoa is one of the major cash crop of Cote d'Ivoire. With 1 964 000 tons in 2018, Côte d'Ivoire is leading the world cocoa beans supply. Unfortunately, this important source of income for the country is under a severe pressure of the Cocoa Swollen Shoot Disease. This disease had been reported for the first time in 1943 in the eastern part of the country. In 2003, important infection areas were reported in the departments of Sinfra and Bouaflé in the Central-West with more than 77.000 ha destroyed. Since that period the disease is reported in several places. But we didn't have a clear idea of all the infected areas. This study aims to study somehow the spread of the disease. The main parameters studied are the incidence and prevalence. The methodological approach consisted in surveys implemented in two steps: 2008-2012 and 2013-2016 on farmer's farms. The study carried out between 2008 and 2012, shows that the CSSD prevalence was 16.37% with 19 regions infected out of 24. The disease reaches 83 departments and 40.680 farms. The second phase of the survey held from 2013 to 2016 shows that the prevalence was 19.51%. It help to highlight a strong progression of the disease in the orchard with 7.734 new farms infected in 111 localities divided into 24 regions. Globally the study shows that the incidence of the CSSD in the orchard ranked from 0% to 76.67 % and the national average is 4.06 %. The areas with low incidence cover 85 localities. The areas with moderate incidence are 25. Doba in San Pedro were the area of highest incidence (76.67%).

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