Cocoa Yield Development of Different Sites, Varieties, Production Systems and Years, in Alto Beni, Bolivia

One of the most essential limiting factors of cocoa (Theobroma cacao L.) productivity worldwide is pests and diseases. Each of the major production regions has its specific pests and diseases. Reported yield losses range from minor to almost 100 per cent. In Alto Beni, located in the Amazonian watershed of the department La Paz, Bolivia, the Research Institute of Organic Agriculture (FiBL) and its local partners are addressing several problems of cocoa producers using a participatory technology development approach. Problems were identified in a participatory way and are, in order of priority, i) to reduce the incidence of pests and diseases, mainly the cocoa mirid (Monalonion dissimulatum) and Frosty Pod Rot (Moniliophthora roreri); ii) to evaluate the productivity of different cocoa varieties (local selections, introduced clones), and iii) to document the management practices and plantation layouts of high yielding cocoa farmers. In order to develop novel biological pest control measures, both the knowledge of cocoa yield development in the course of the harvest period, as well as the dynamics of pests and diseases are of great interest. Data from three different research activities of the mentioned project are analysed for yield development, the appearance, and the incidence of pests and diseases, where available. The research data are from: a) On-farm trials in multiple locations which were established in 2004. The performance of 16 cocoa varieties has been assessed for 3 years (2010–2012). b) Four high yielding cocoa farmers’ fields (2012 only). c) A long-term field experiment assessing the sustainability of five cocoa production systems (2011 and 2012). The trial investigates the influence of monocultures and different agroforestry systems under organic and conventional management on the yield development, among other agronomic, economic and environmental parameters

Systems and Managements Related Differences in Phenology of 12 Cocoa (Theobroma cacao L.) Cultivars

Cocoa production systems can vary from a mono-cropping (MC) full sun plantation to a highly diversified successional agroforestry (SAFS). Mono-cropping is still the most common one but recently agroforestry (AF) systems have raised more interest because of their expected long term resilience. Nevertheless, information about the influence of cropping systems and management methods such as organic versus conventional in cocoa production and phenology in South America is missing. This study is based on the SysCom program’s framework located in Alto Beni (Bolivia), where three cropping system (MC, AF and SAFS) are compared. Additionally, MC and AF systems are conventionally and organically managed. A total of 12 cultivars including local clones, foreign clones (from the Imperial College Selections and Trinidad Selections) and hybrids are planted in each system. The aim of the present study is to identify differences between systems, management methods, cultivars and the respective interactions on cocoa phenology. Data on flushing and number of flowers, small, medium and big fruits and cherelles are being recorded every 15 days from March 2015. The trial was designed according to a split plot design with four replicates. Principal component analysis (PCA) and cluster analysis were performed on the cultivar level. Additionally, the collected data will be statistically analysed with a generalised mixed model (Poisson distribution) to test the effect of the different cultivars, systems and their interactions on the phenological traits. Preliminary results of the PCA and cluster analysis do not show a clear grouping pattern between the three types of genotypes analysed. This suggests that there are differences between cultivars but they are not consistent within the three groups. Preliminary descriptive results of the collected traits show differences between single cultivars and systems, but not between managements (organic vs. conventional). Some of the traits seem to be more system dependent than others. For instance, the number of cherelles seems to be higher in the SAFS than in the other systems. Additionally, interactions between systems and cultivars are expected to be present. This would be positive in terms of potentiality for selection of cultivars adapted to each different system

Comparison of Methods to Assess Dry Bean Yield of Different Cocoa Cultivars

To estimate the cocoa dry bean weight from the fresh weight a standard dry bean factor (DBF) ranging from 32% to 40% is usually applied. This factor, i.e. the relation between the dry bean weight (fermented and dried) and the fresh weight at pod opening, is used by cooperatives and factories that buy the fresh beans of the farmers. However, this factor is subjected to seasonal fluctuations and can be highly influenced by rainfall. Therefore, for instance, higher values are expected during the dry season compared with the rainy season. The objective of this study was to evaluate the accuracy of the use of a standard fix DBF value compared with the use of actual DBF values periodically collected over the season for assessing the performance of 12 cocoa cultivars (clones and hybrids). We hypothesised that using the same DBF for different cultivars that may have the production peak at different times of the season can lead to over- or underestimations of the yield performance. The study was performed in a long-term cocoa trial in Alto Beni, Bolivia, which comprises full-sun monocultures, agroforestry and successional agroforestry productions systems. In 2014, for each harvest date, cultivar and production system, a subsample of the fresh beans was collected, put in a mesh bag and weighted. After the fermentation and drying process, the subsamples were weighted again and the DBF was then calculated at 8% water content of the beans. The total performance of each cultivar at the end of the harvest season was estimated using the actual DBF for each cultivar, system and harvest date, and the results were compared with the performance estimated using the DBF values averaged across systems, harvest dates and varieties and also with the fixed DBF of 35%. The results only showed minor differences in the overall performance of each cultivar when comparing the different methods used. However, for all the cultivars, using the 35% fix value gave the poorest estimation compared with any of the other DBF tested, mainly due to underestimation of the performance of the early maturing cultivars

Cocoa Yield Development in Alto Beni, Bolivia: Influence of Sites, Varieties and Years

One of the most essential limiting factors of cocoa (Theobroma cacao L.) productivity worldwide is pests and diseases. Each of the major production regions has its specific pests and diseases. Reported yield losses range from minor to almost 100 per cent. In Alto Beni, located in the Amazonian watershed of the department La Paz, Bolivia, the Research Institute of Organic Agriculture (FiBL) and its local partners are addressing several problems of cocoa producers using a participatory technology development approach. Problems were identified in a participatory way and are, in order of priority, i) to reduce the incidence of pests and diseases, mainly the cocoa mirid (Monalonion dissimulatum) and Frosty Pod Rot (Moniliophthora roreri); ii) to evaluate the productivity of different cocoa varieties (local selections, introduced clones), and iii) to document the management practices and plantation layouts of high yielding cocoa farmers. In order to develop novel biological pest control measures, both the knowledge of cocoa yield development in the course of the harvest period, as well as the dynamics of pests and diseases are of great interest. Data from three different research activities of the mentioned project are analysed for yield development, the appearance, and the incidence of pests and diseases, where available. The research data are from: a) On-farm trials in multiple locations which were established in 2004. The performance of 16 cocoa varieties has been assessed for 3 years (2010–2012). b) Four high yielding cocoa farmers’ fields (2012 only). c) A long-term field experiment assessing the sustainability of five cocoa production systems (2011 and 2012). The trial investigates the influence of monocultures and different agroforestry systems under organic and conventional management on the yield development, among other agronomic, economic and environmental parameters

Cocoa agroforestry systems vs. monocultures under conventional and organic management - results from tropical Bolivia

Cocoa is one of the most important export commodities for many developing countries and provides income for millions of smallholders. The expansion of cocoa production has resulted in habitat destruction, biodiversity loss, and soil degradation. The prevalent cocoa production systems worldwide are conventional monoculture full sun systems. Agroforestry systems are argued to be a viable strategy for sustainable cocoa production. However, data-based information on advantages and limitations of different cocoa production systems is limited. Pairwise comparisons on the long-term performance of cocoa monocultures and agroforestry systems under conventional and organic management are inexistent. FiBL is pioneering to fill this knowledge gap with a unique long-term field trial in tropical Bolivia established in 2008. The trial consists of six treatments: two monocultures (MONO CONV/ORG) and two agroforestry system (AF CONV/ORG) under conventional and organic management, one organic successional agroforestry system (SAFS) with dynamic shade management, and a fallow of the same age serving as a reference for biodiversity and soil fertility studies. The treatments are representative for current cocoa production systems of smallholders. Parameters regularly assessed include canopy openness, cocoa stem diameter and bean yield, pests and diseases, soil fertility, carbon stocks, economic data and biodiversity. Five years after planting, results showed significantly shorter tree circumference (18% and 33%) in AF systems and SAFS, respectively, compared to MONO systems. Tree circumference correlated strongly with cocoa bean yield, and highest bean yields were recorded in MONO CONV as expected. Additional products like banana/plantain, cassava, pineapple, etc. were harvested in AF systems and SAFS, which may compensate for lower cocoa yield in the first years. First results indicate that disease incidences were higher in MONO systems compared to AF and SAFS. Future research will investigate cocoa performance after the establishment phase and thus provide indications on the long-term sustainability of the different systems

Labour Demand in Five Different Cocoa Production Systems in Bolivia

Cocoa cropping systems vary from full-sun monocrops to highly diversified agroforestry systems, which combine the cocoa production with by-crop such as bananas or plantains and trees with different functions. Additionally, these systems can be organically or conventionally managed. Although labour demand is one of the main activities contributing to the total production costs of the plantations and it may highly differ between production systems, there are still scarce data and information available. In this study we present the labour demands of five different production systems in a newly established cocoa plantation in Alto Beni, Bolivia. The trial was established in 2008 within the framework of the SysCom programme (www.systems-comparison.fibl.org) and comprises monoculture and agroforestry systems under organic and conventional management and one successional agroforestry system with organic management, each one replicated four times. From 2009 to 2013, the establishment phase of the plantation, the time spent in all the farming activities, mainly weeding, pruning, harvesting and fertilising was recorded separately for each plot. Overall, total labour demand was higher in the successional and agroforestry systems compared with the monocultures, mainly due to the time devoted to the management of the multifunctional trees and by crops. However, no significant differences were found between organic and conventional management under both agroforestry and monoculture systems. On the contrary, the time needed for pruning the cocoa trees was higher in the monocultures. Similarly, the time spent in cocoa harvesting was also higher in the monocultures, especially under conventional management, which well correspond to the yield obtained. Weeding was high time demanding the first years of the plantation but decreased with the time. However, no differences between the monoculture and agroforestry systems and between the organic and conventional management were found. An economic analysis of the gross margins for each system at plot level, including the input costs (herbicides, fertilisers, etc.) and the associated cost for their preparation (e.g. compost preparation), and the income generated from the harvested produces (cocoa, banana, plantain and other by-crops out of the highly diversified system ) is under evaluation

Cocoa in Full-sun Monocultures vs. Shaded Agroforestry Systems under Conventional and Organic Management in Bolivia

Cocoa is a crucial export commodity for many developing countries and provides income for millions of smallholders. However, cocoa cultivation has resulted in habitat destruction, biodiversity loss and soil degradation. While much of the world’s cocoa is produced in arguably unsustainable full-sun monoculture systems, shaded agroforestry systems may be an alternative for sustainable cocoa production. However, data-based information on advantages and limitations of different cocoa production systems are limited and pairwise comparisons on the long-term performance of cocoa monocultures and agroforestry systems under conventional and organic management are literally inexistent. The Research Institute of Organic Agriculture (FiBL) is pioneering to fill this knowledge gap with a unique long term field trial in tropical Bolivia. The trial was established in 2008 and consists of six systems: two monocultures (MONO CONV/ORG) and two agroforestry systems (AF CONV/ORG) under conventional and organic management, one successional agroforestry system (SAFS, organic only) with dynamic shade management, and a fallow system of the same age serving as a reference for biodiversity and soil fertility studies. The systems aim to represent current smallholder cocoa farmers’ practices. Parameters such as the tree development, yield of cocoa and by-crops, incidences of pests and diseases, soil fertility, carbon stocks, nutrient balances, economic data and biodiversity are regularly assessed. Five years after planting, results showed significantly shorter tree circumference (18% and 33 %) in AF systems and SAFS, respectively, compared to MONO systems. Tree circumference correlated strongly with cocoa dry bean yield which was, as expected, highest in MONO CONV (603 kg ha−1). By-crops such as plantain, cassava, pineapple, etc. were harvested in AF systems and SAFS, which may compensate for lower cocoa yields in the first years. Future research will investigate cocoa performance after the establishment phase and thus provide indications on the long-term sustainability of the different systems

Evaluation of organic pest management strategies to control the cocoa mirid (Monalonion dissimulatum Dist.), Alto Beni, Bolivia

The cocoa mirid (Monalonion dissimulatum) is one of the major pests in cocoa cultivation in Alto Beni, Bolivia, causing up to 50% yield losses. The most common control method is the manual removal of the nymphs sucking at the pods in the morning. This practice is very time-consuming, and farmers often do not dispose of enough time to perform these control measures. Therefore, there is an urgent need for more efficient practices to control this important pest. The present study evaluated the pathogenicity of two strains of Beauveria bassiana for the control of Monalonion dissimulatum on cocoa: a non-native, commercialized strain (Probiobass MR, Probiotec S.R.L.), and a native strain of Alto Beni, which is not yet commercialized (isolated by the local association SIEMPRE). Moreover, a silicon-based product (TECSIL PM®) was tested. In addition, the effect of different degrees of infestation with Monalonion dissimulatum on different stages of cocoa pod development was examined. In order to investigate these questions, several different field trials were carried out at the experimental station of Sapecho between June and September 2013. The foreign strain of Beauveria Bassiana was the most effective bio-pesticide, causing a mortality rate of 63.3% in adults and 49.1% in nymphs of Monalonion dissimulatum. Cocoa pods in their early stages of development were highly susceptible to attack by Monalonion dissimulatum. On the other hand, fully developed cocoa pods showed a rather strong resistance to attacks by Monalonion dissimulatum: up to about 70% of damaged tissue on the surface of the cocoa pods, no effects on cocoa wet bean yield were recorded. However, when the damage increased above 70%, it had a strong impact on yield, amounting up to 50.4% yield loss. Fully damaged pods started drying out, and if they were completely desiccated, the yield loss was total. It is concluded that the foreign strain of Beauveria Bassiana may be the most efficient to control Monalonion dissimulatum in the field. More on-farm field trials need to be conducted over longer time periods in order to elucidate whether the observed effects will be reflected in higher cocoa yields in the farmer’s context. It is recommended to perform harvesting operations at regular intervals of two weeks in order to minimize losses caused by the desiccation of damaged cocoa pods

Cocoa Yield in Bolivian On-Farm Trials 2010-2013 – Monitoring Outstanding Farmers and Comparing Clones and Sites

Cocoa (Theobroma cacao L.) trees have a lifespan of up to 100 years in their natural environment, the lower strata of tropical alluvial forests. Sustainability of global cocoa production is at stake due to the deterioration of soil fertility, high losses due to pests and diseases (P&D) and old tree stock. Producing cocoa in shaded, low input agroforestry systems offers a potential solution for achieving long-term productivity and sustainability. However, shade-tolerant cocoa clones are needed which are productive and resistant to P&D, as well as meeting the quality standards requested by the industry. In Bolivia, the cocoa mirid (Monalonion dissimulatum) and the novel disease Frosty Pod Rot (“Monilia” Moniliophthora roreri) are among the most devastating P&D. The Research Institute of Organic Agriculture (FiBL) and its local partners have been conducting cocoa production systems research in the Alto Beni region of Bolivia since 2008. A participatory rural appraisal revealed that indeed, how to reduce incidences of the cocoa mirid and Frosty Pod Rot was the top priority of cocoa farmers. Furthermore, a need for evaluating the productivity of different cocoa clones and for the documentation of best practices was expressed. In order to address these points, several research activities were carried out: 1. 16 cocoa clones have been evaluated for productivity and susceptibility to P&D for four consecutive years (2010—13) in on-farm trials at multiple locations. 2. The yield development and prevalence of P&D in the fields of four outstanding farmers was assessed for two years (2012–13) Data analysis revealed that some locally selected clones (elite tree selection program) were not only among the most productive, but also showed earliest maturation and some degree of resistance to Monilia (i.e. with lower incidences of the disease). Thus these clones hold the potential to escape attacks by P&D which occur later on in the season and may serve as a basis for further germplasm development towards clones with resistance to Monilia. However, before disseminating information to farmers and farmers’ organisations, sound scientific data from at least five years is required