The use of date palm (Phoenix dactylifera L.) has been closely connected with the survival of people in arid areas given their fruits´ high concentration of energy, fibre, minerals, vitamins and 16 amino acids. The arid climate and sandy or clayey loam soils in many parts of Pakistan are ideal for the cultivation of date palm, which contributes to feeding the country's rapidly growing population. To fill knowledge gaps on the effects of cultivar diversity and cultivation sites on the nutritional properties of dates, the present project studied dates and related physical and chemical soil properties across six districts in four provinces of Pakistan: Jhang, Muzaffargarh and Bahawalpur in Punjab; Dera Ismail Khan (D. I. Khan) in Khyber Pakhtunkhwa (KPK); Khairpur in Sindh and Panjgur in Baluchistan. To this end, during 2012–2013, a total of 170 households (HHs) were selected using a snowball sampling approach. Thirty-nine different date palm cultivars with diverse nutritional properties are grown in the study area. In these total soluble solids (TSS) were highest in Muzawati and Koharba cultivars, while cultivars and site conditions significantly affected TSS, minerals (calcium and magnesium), acidity, and firmness of dates. Concentration of CaCO3 and bulk density (BD) of soils varied widely, while hydraulic conductivity (HC) was similar across sites (p = 0.128). Mean soil pH was highest in Panjgur (8.3) and lowest in Muzaffargarh (7.6), soil organic matter content was highest in Jhang (0.8%) and lowest in D. I. Khan (0.6%) and plant available phosphorous (P) was highest in Muzaffargarh (7.8 mg kg−1) and lowest in Panjgur (6.0 mg kg−1). As indicated by correlation analysis BD and cation exchange capacity of soils seemed to affect TSS, whereas concentration of CaCO3 and available P were correlated with calcium concentration of dates. HC and electrical conductivity, however, seemed to have little effect on dates´ nutritional properties.

The worldwide cultivation of fig (Ficus carica L.) has achieved great economic importance, mainly, due to its important role as a food supplement. This situation has generated great interest in researching its methods of production, processing and conservation. The objective of this research was to evaluate six intensive production systems of fig in hydroponic and greenhouse conditions. The experimental phase started on November 15, 2010 and was completed in September 2011. Production systems were established by varying the number of productive stems between three and eight in each plant, with densities of 1.25 plants m−2. A completely experimental – randomized design was used with five replications, with a pot and a plant as an experimental unit. The results indicate that the highest yielding of fresh fruit was presented by eight productive stems (109.5 t ha−1), this one outperformed the seven productive stems (94.8 t ha−1) in 13.3% and six productive stems (78.6 t ha−1), at 26.8%. The handling of productive stems allowed an increase in the leaf area index, harvest index and fruit yielding. These results suggest that intensive production in hydroponic and greenhouse conditions of fig is an excellent alternative production, allowing to collect up to 20 times of fresh fruit yielding in relation to the plantations in the open field.

Cocoa (Theobroma cacao L.) is produced in systems of varying complexity ranging from monoculture with temporary shade to highly diverse agroforests. Producers have to weigh high cocoa yields in the short to medium term in monocultures against higher total system yields in the short term and sustainable production systems in the long term in conjunction with ecosystem services in agroforestry systems (AFs). More long-term data on the comparative agronomic, economic and ecological performance of differently managed cocoa production systems is required to make sound recommendations to farmers. This paper describes the only long-term field trial worldwide comparing different cocoa production systems under conventional and organic management. The factors (i) crop diversity (monoculture vs. agroforestry), (ii) management practice (conventional vs. organic) and (iii) cultivar are being tested in a full-factorial, randomized complete block design with four replications. First, results showed significantly faster development of trunk circumferences in monocultures (+21%) compared to AFs. Cocoa yields were 47% lower in the organic compared to the conventional monoculture. In the AFs, however, the organic–conventional yield gap was less pronounced (−16%) and statistically insignificant. The cumulative yields of all products harvested were significantly higher in the AFs (+161%) compared to the monocultures. The productivity of cocoa by-crops in AFs may contribute to local food security and risk distribution in smallholder contexts.

Legumes have gained increased importance in smallholder farming systems of sub-Saharan Africa due to their contribution to household nutrition and health and their ability to grow in low fertility soils. With unpredictable and highly variable rainfall characteristics of the semi-arid areas, short-season grain types are seen as a promising option for drought avoidance. Knowledge of phenological development and, in particular, time to flowering is crucial information needed for estimating the possible production success of new accessions to new environments. The photoperiod-sensitivity of 10 promising short-season Lablab purpureus (L.) Sweet accessions (CPI 525313, CPI 52533, CPI 52535, CPI 52535, CPI 52552, CPI 52554, CPI 60795, CPI 81364, CQ 3620, Q 6880B) were evaluated for their response to varying temperature and daylength regimes in field trials in Limpopo province, South Africa and under controlled conditions in growth chamber experiments in Göttingen, Germany. Photoperiod sensitivity was quantified using the triple-plane rate model of flowering response with time to flowering expressed in thermal time (Tt, °Cd). Additionally, piecewise regression analysis was conducted to estimate the critical photoperiod (Pc) above which time to flowering was delayed significantly. Relatively high variation of time to flowering amongst and within accessions in days after planting (DAP) was observed, ranging from 60 to 120 DAP depending on sowing date or daylength/temperature regime. Furthermore, a clear positive effect of temperature on growth and development of the tested accessions was found and time to flowering expressed as thermal time were consistent for the tested accessions, ranging from 600 to 800 °Cd for daylength <13 h. Only at daylength of ≥13 h and temperatures above 28 °C, development towards flowering was delayed significantly for accessions CPI 52513, CPI 52535, CPI 52554 and CPI 60795 with vegetative growth continuing for >110 DAP. The tested lablab accessions are therefore considered photoperiod insensitive, or weakly photoperiod responsive and are classified as short-day plants (SDP). Since daylength does not exceed 13 h between the latitudes 30 N to 30 S, these lablab accessions are recommended for further testing as short-duration grain legumes.

Soybean yields on smallholder farmers’ fields in Malawi are constrained by poor soil fertility, limited application of external inputs and poor crop husbandry. We tested crop management practices through on-farm experimentation and participatory technology evaluation. Two agronomic soybean trials were established in 2009 and 2010 in three contrasting agro-ecologies resulting in 72 replications per trial. Treatments in the first trial included several combinations of inoculation with Bradyrhizobium japonicum, inorganic fertiliser application and compost manure. In the second trial, farmers tested an improved variety, optimal weeding regime, increased plant population and chemical pest and disease control. A combination of inoculation, inorganic fertiliser (10 N, 8 P, 20 K in kg ha−1), and 6 t ha−1 compost manure increased yields from 0.86 t ha−1 under farmers’ practice to 1.56 t ha−1 and resulted in average profits of US$222 ha−1. Increased plant populations and biocide spraying also resulted in substantial yield increases. Inoculation and increased plant population resulted in an average value to cost ratio (VCR) > 2. Low investment costs make inoculants, compost manure and increased plant populations interesting options, whereas adoption of inorganic fertiliser application in soybean may be limited due to high costs and low VCR. The farmers ranked eight technologies in descending order of preference as: (i) early planting, (ii) plant population, (iii) variety choice, (iv) compost manure, (v) weeding, (vi) inoculant, (vii) fertiliser and (viii) spraying. Our participatory research approach demonstrated that there is a wide range of technologies with different levels of human and financial investment costs that smallholder farmers can adopt to enhance their soybean yields and profits.

Most cocoa farms in Ghana are cultivated in complex agroforest systems, with plant growth and cocoa productivity being affected. The objective of this study was to investigate how shade trees affect cocoa yield, temperature and soil nutrients in low-input cocoa systems. Establishing plots on 24 farms in four locations (districts) in Ghana, we assessed the influence of varying canopy cover and fertilization on cocoa yields. Results showed no relationship between canopy cover and cocoa yields in the light crop season (February to August). For the main crop season (September to January), there was an interaction between shade and yields: Yields were higher on no-shade plots than on shaded plots in two districts, whilst there were no differences at the two other districts possibly due to differences in precipitation and soil nutrient status. On the other hand, there was a positive effect of increased canopy cover on yields within the shaded plots. Soil nutrient analyses revealed no significant differences between shaded and no-shade plots and adequate levels of N, K+, Fe2+, Cu2+ and Zn2+ were recorded. However, soil contents of P, C, Mg2+ and Ca2+ were below recommended values. Peak temperatures recorded in the cocoa canopies were above the recommended range for this species. Although shade trees had a slight modifying effect on peak temperatures, the magnitude appeared too small to have any practical effects.

Low soil pH and associated soil infertility problems are considered to be amongst the major challenges to barley production in the highlands of Ethiopia. In response to this, an experiment was conducted at low soil pH (< 5 H2O) site on the effects of different levels of lime and phosphorus (P) fertilizer on soil pH, exchangeable aluminium (Al3+), grain yield and yield components of barley during 2010 and 2011 cropping seasons. The experiment comprised factorial combinations of five lime rates (0, 0.55, 1.1, 1.65 and 2.2 t ha−1) and four P rates (0, 10, 20 and 30 kg ha−1) in a randomized complete block design in three replications. The amount of lime that was applied at each level was calculated on the basis of Al3+. Results of soil analysis after 2 years of liming showed that liming significantly (P < 0.05) increased soil pH, and markedly reduced exchangeable Al3+. Liming at the rate of 0.55, 1.1, 1.65 and 2.2 t ha−1 decreased Al3+ by 0.88, 1.11, 1.20 and 1.19 mill equivalents per 100 g of soil, and increased soil pH by 0.48, 0.71, 0.85 and 1.1 units, respectively. Amongst the liming treatments, liming at the rate of 1.65 and 2.2 t ha−1 gave significantly (P < 0.05) the highest grain yield and yield components of barley. However, grain yield obtained by applications of 1.65 and 2.2 t ha−1 lime was statistically comparable. By additions of 10, 20 and 30 kg P ha−1, grain yield of barley increased by about 29, 55 and 66% as compared to control (without P). During 2010, however, the combined applications 1.65 t ha−1 lime and 30 kg P ha−1 gave 133% more grain yields of barley relative to control (without P and lime). Therefore, sustainable barley production on acid soils in the central highlands of Ethiopia should entail combined applications of both lime and P fertilizer.

The yield gap has arisen again as a focus for agricultural research to ensure food security and economic growth for farmers around the world. To examine this renewed interest, we carried out a review of key literature in the field of yield gap analysis to identify important gaps in research and analysis. In so doing, both the complexities in yield gap studies emerged along with some significant omissions. Much of the literature and research on the yield gap has been framed by larger concerns and initiatives to raise agricultural productivity. This focus has led to an emphasis on technical solutions such as crop breeding, fertilizer application and other methods to increase production. However, this concentration on the technical usually ignores the wider social, economic and political context that shapes farmer decision-making about agricultural production. This context can either discourage or enable farmers to close their yield gap. Additionally, the impact of increased agricultural production through certain technical solutions also often overlooks the wider impact on the landscape and the ecosystem services which underpin agricultural production and livelihoods. We argue that increasing agricultural productivity, and closing the yield gap, must be addressed with this broader approach.

Numerous innovation platforms have been implemented to encourage the adoption of agricultural innovations and stakeholder interactions within a value chain. Yet little research has been undertaken on the design and implementation of innovation platforms focussing on issues other than market access and aiming to encourage agro-ecological intensification. This is the case for the development of Conservation Agriculture (CA) in West Africa, which due to its complex nature calls for technical, organizational and institutional changes at the level of both production systems and village territories. This article analyses the design and implementation process of platforms in three villages in Burkina Faso aiming to develop CA technical references with local stakeholders, and to renew rules of interaction between stakeholders within a territory. The platforms enabled farmers in the three villages to actively participate in the identification of the cropping systems that were tested and to improve their knowledge and mastery of CA. They furthermore promoted networking among producers and facilitated the development of new rules for crop residue use. The platforms thus appear to be relevant mechanisms, enabling complex innovations to be addressed. Diverse modifications and improvements are discussed that would ensure the sustainability of the platforms and the evolution of their objectives and activities beyond those of the project under which they were launched.