Do wealthy farmers implement better agricultural practices? An assessment of implementation of Good Agricultural Practices among different types of independent oil palm smallholders in Riau, Indonesia

Palm oil has become a leading vegetable oil over the past 30 years and smallholder farmers in Indonesia, with more than 12 million hectare the world's largest producer of palm oil, have massively engaged in oil palm (Elaeis guineensis) cultivation. In Sumatra, where more than 60% of Indonesian palm oil is cultivated, smallholders currently cover roughly 50% of the oil palm area. The rapid expansion of palm oil however did not happen without controversy. In current efforts by the Indonesian government, NGO's and private sector to improve sector performance, smallholders are often characterized as the Achilles heel of the oil palm sector due to poor practices and low yields compared to companies. However, 'oil palm smallholders' is a container concept and there has been only limited research into smallholder diversity beyond the organised versus independent farmer dichotomy. This research delves into the implementation of Good Agricultural Practices (GAP) among seven types of independent smallholders in Rokan Hulu regency, Riau province. The research area consisted of a relative established agricultural area on mineral soils and a relative frontier, mostly on peat. Smallholder types ranged from small local farmers to large farmers who usually reside in urban areas far from their plantation and regard oil palm cultivation as an investment opportunity. The underlying hypothesis is that larger farmers have more capital and therefore implement better agricultural practices than small farmers, who are usually more cash constrained. A wide range of methods was applied, including farmer and farm surveys, remote sensing, tissue analysis and photo interpretation by experts. These methods provided data on fertilizer use, nutrient conditions in oil palms, planting material, planting patterns, and other management practices in the plantations. Results show that yields are poor, implementation of GAP are limited and there is much room for improvement among all farmer types. Poor planting materials, square planting patterns, and limited nutrient applications were particularly prevalent. This implies that farmers across different typologies opt for a low-input low-output system for a myriad of reasons and that under current conditions, initiatives such as improving access to finance or availability of good planting material alone are unlikely to significantly improve the productivity and sustainability of the smallholder oil palm sector

The seco-iridoid pathway from Catharanthus roseus

The (seco)iridoids and their derivatives, the monoterpenoid indole alkaloids (MIAs), form two large families of plant-derived bioactive compounds with a wide spectrum of high-value pharmacological and insect-repellent activities. Vinblastine and vincristine, MIAs used as anticancer drugs, are produced by Catharanthus roseus in extremely low levels, leading to high market prices and poor availability. Their biotechnological production is hampered by the fragmentary knowledge of their biosynthesis. Here we report the discovery of the last four missing steps of the (seco)iridoid biosynthesis pathway. Expression of the eight genes encoding this pathway, together with two genes boosting precursor formation and two downstream alkaloid biosynthesis genes, in an alternative plant host, allows the heterologous production of the complex MIA strictosidine. This confirms the functionality of all enzymes of the pathway and highlights their utility for synthetic biology programmes towards a sustainable biotechnological production of valuable (seco)iridoids and alkaloids with pharmaceutical and agricultural applications

On yield gaps and better management practices in Indonesian smallholder oil palm plantations

Palm oil is currently the most important vegetable oil in the world, and Indonesia is the world’s largest producer. Oil palm plantations are an important source of revenue, but rapid expansion has led to deforestation and loss of biodiversity. Forty per cent of the plantation area in Indonesia is owned by smallholders, whose yields are relatively poor. The objective of this thesis was to investigate the yield gaps and agronomic practices in Indonesian smallholder oil palm plantations, with a focus on fertiliser application, and to propose and test better management practices that can contribute to sustainable intensification. The research consisted of an in-depth literature review, several surveys, the collection of samples in smallholder plantations, and a three-year experiment with 14 smallholder farmers. In yield gap analysis, three yield levels are recognised: potential, limited, and actual yield. The potential yield in a plantation is determined by radiation, CO2 concentration, temperature, planting material, culling, planting density, pruning, pollination, and crop recovery (harvesting). The yield-limiting factors are rainfall, irrigation, soil, waterlogging, topography, slope, and nutrition. The yield-reducing factors are weeds, pests, and diseases. In smallholder plantations, the yield gap is mostly explained by poor planting material, poor drainage, sub-optimal planting density, poor culling (leading to large variability and the presence of unproductive palms), infrequent harvesting, soil erosion, poor nutrient management, and rat damage, but the effects of these factors on yield vary depending on local conditions. The survey data showed clear evidence of insufficient and unbalanced fertiliser applications, and visual nutrient deficiency symptoms were observed in many plantations. Leaf sample results showed that 57, 61 and 80% of the plantations in Jambi and Sintang were deficient in N, P and K, respectively. In Riau, 95, 67 and 75% of the plantations were deficient in N, P and K. The implementation of better management practices (including harvesting, weeding, pruning, and nutrient application) in 14 smallholder fields for three years resulted in palms with significantly larger leaves and heavier bunches compared with palms under farmer management, but improvements in yield were small and not statistically significant, and financial returns on better practices were negative. Possible causes of the small yield response were good starting yields, increased inter-palm competition for sunlight, and environmental constraints (particularly the 2015 El Niño event and waterlogging in Jambi). On the basis of our findings on yield gaps, nutrient limitations and better practices, we discuss how Indonesian smallholders may be supported to achieve sustainable intensification at a larger scale, and we reflect on the broader implications of our findings for a future supply of truly sustainable palm oil

Nutritional imbalance in smallholder oil palm plantations in Indonesia

In Indonesia more than 40% of the area under oil palm is owned by smallholders. The productivity in smallholder plantations is usually less than in large plantations, and limited fertiliser applications may be one of the key reasons. We investigated the use of fertilisers by > 300 smallholder farmers in Sumatra and Kalimantan, some of whom were involved in training programmes aimed at yield improvement. In our sample, the total applications of N were largest (166 kg ha−1 year−1), followed by K (122 kg) and P (56 kg). The applications of K were insufficient to compensate for the off-take with a production of 20 tonne fruit bunches ha−1 year−1, while N applications were excessive. On average, farmers applied 1130 kg fertiliser ha−1 year−1, and relied strongly on subsidised fertilisers, especially NPK Ponska (66%) and urea (39%). The average costs for fertiliser application were USD 225 ha−1 year−1. Trained farmers applied significantly more P in one research area, but for the other nutrients and research areas, there was no significant difference between trained and untrained farmers. Plantation size and nutrient application were weakly correlated in some areas, but not in the sample as a whole. Previously reported nutrient application rates were mostly less than our findings indicated, suggesting that actual nutrient limitations may be more severe. To overcome nutrient limitations and enhance nutrient use efficiency, we recommend that fertilisers are used in the correct balance; a ground cover vegetation is maintained to protect against erosion; and the application of empty fruit bunches is encouraged

Yield gaps in oil palm : A quantitative review of contributing factors

Oil palm, currently the world's main vegetable oil crop, is characterised by a large productivity and a long life span (≥25 years). Peak oil yields of 12 t ha−1 yr−1 have been achieved in small plantations, and maximum theoretical yields as calculated with simulation models are 18.5 t oil ha−1 yr−1, yet average productivity worldwide has stagnated around 3 t oil ha−1 yr−1. Considering the threat of expansion into valuable rainforests, it is important that the factors underlying these existing yield gaps are understood and, where feasible, addressed. In this review, we present an overview of the available data on yield-determining, yield-limiting, and yield-reducing factors in oil palm; the effects of these factors on yield, as measured in case studies or calculated using computer models; and the underlying plant-physiological mechanisms. We distinguish four production levels: the potential, water-limited, nutrient-limited, and the actual yield. The potential yield over a plantation lifetime is determined by incoming photosynthetically active radiation (PAR), temperature, atmospheric CO2 concentration and planting material, assuming optimum plantation establishment, planting density (120–150 palms per hectares), canopy management (30–60 leaves depending on palm age), pollination, and harvesting. Water-limited yields in environments with water deficits >400 mm year−1 can be less than one-third of the potential yield, depending on additional factors such as temperature, wind speed, soil texture, and soil depth. Nutrient-limited yields of less than 50% of the potential yield have been recorded when nitrogen or potassium were not applied. Actual yields are influenced by yield-reducing factors such as unsuitable ground vegetation, pests, and diseases, and may be close to zero in case of severe infestations. Smallholders face particular constraints such as the use of counterfeit seed and insufficient fertiliser application. Closing yield gaps in existing plantations could increase global production by 15–20 Mt oil yr−1, which would limit the drive for further area expansion at a global scale. To increase yields in existing and future plantations in a sustainable way, all production factors mentioned need to be understood and addressed

Farmers’ Perceptions as a Driver of Agricultural Practices: Understanding Soil Fertility Management Practices in Cocoa Agroforestry Systems in Cameroon

International audienceIn Africa, cocoa yields are low, partly due to soil fertility constraints and poor management. While peoples’knowledge, aspirations,and abilities are key factors explaining their behaviour, little is known about the rationales that underpin soil fertility managementpractices (SFMPs) of cocoa farmers. To address this gap, we conducted an exploratory survey in two contrasting regions in Cameroonwhere cocoa is an important crop: the humid forest and the forest-savannah transition zone. Some 30% of farmers in the transition zoneas opposed to 13% in the humid forest expressed concerns about soil fertility. The most relevant soil fertility indicators for farmerswere high cocoa yield, dark soil colour, ease of tillage, and floral composition. To enhance and maintain soil fertility, farmers usedresidues from weeding (100%), planting of trees (42%), mineral fertilisers (33%), compost (16%), and manure (13%). More farmers inthe transition zone than the humid forest implemented SFMPs. Our findings suggest that soil fertility perceptions, access to inputs,local practices, and experience influence farmers’use of SFMPs. The limited use of mineral fertilisers was explained by poor accesswhereas the use of organic fertilisers and tree planting were mostlyconstrained by lack of labour and knowledge. Farmers prioritisedpractices to increase yield and viewed SFMPs to be the least important management practices, although they believe high cocoa yieldis an important indicator of soil fertility. To foster sustainable cocoa intensification, it is necessary to enhance farmers’knowledge onSFMPs, increase access to inputs, and ensure returns on investment while considering farmers’priorities and practice