The establishment of leys for biomass production during the winter months could be an alternative feed resource of low cost for small ruminants in Mediterranean basin. For this purpose, an experiment was carried out with six plant species mixtures (PSM) that were cut up to seven times from seeding. The results showed that all the PSM had their highest growth at the 2nd cut with Festuca arundinacea, Lolium perenne, Dactylis glomerata, Trifolium repens (FLDT) being superior as the dry matter production concerns compared with the PSM that gave seven cuts. The crude protein and the ether extracts contents in all the PSM decreased from the 1st to the last cut, while that of NDF and ADF increased. The concentrations of myristic, palmitic, stearic, oleic and linoleic acid increased in all the PSMs from the 2nd to the 5th cut, while the opposite was observed for the α-linolenic acid content. The concentration of α-linolenic acid was higher in the FLDT PSM when compared to others during all cuts. Taking into account all the examined parameters together, the FLDT seems to be superior to the other PSMs as animal feed for small ruminants, particularly during the period where there is no available grass from natural grasslands.

In a three-year field experiment on acid peat (pH 3.47) up to 12 t/ha lime increased peat pH (0–30 cm depth) by 0.061/t. Annual guinea grass dry matter increased in quadratic relation with liming up to pH 4.20 (12 t/ha lime) but there was no difference between the cvs Sigor and Colonoa. Liming decreased the N, P and K, but increased the Ca and Mg contents of the harvested grass. Liming also increased the uptake of all five nutrients investigated, either linearly or curvilinearly.

The perennial forage peanut is a stoloniferous, perennial tropical legume with potential for use in pastures. Based on the hypothesis that under intermittent stocking herbage accumulation would follow a similar pattern to that described for tropical forage grasses, the objective of this study was to evaluate canopy characteristics and herbage accumulation of forage peanut subjected to strategies of rotational grazing management. Treatments corresponded to all possible combinations of two grazing frequencies (regrowth interrupted at 95% and maximum canopy light interception – LI95% and LIMax) and two grazing severities (post-grazing canopy heights (CHs) equivalent to 40 and 60% of the pre-grazing heights). Treatments were imposed to experimental units during an adaptation period (from November 2014 to January 2015) and the subsequent experimental period lasted from February 2015 to April 2016, comprising two consecutive pasture growing seasons with no interruption between them (summer I to summer II). The pre-grazing targets of LI95% and LIMax corresponded to CHs of 13 and 18 cm, respectively. Forage peanut showed high grazing tolerance as pre-grazing leaf area index (except during summer I and autumn/winter), total herbage, and leaflet dry matter accumulation varied only with seasons. Higher rates of herbage production were recorded during summer I and summer II, followed by those during late and early spring and autumn/winter. Since there was no difference in the pattern of herbage accumulation between LI95% and LIMax and stolons predominated at the bottom of the canopies, forage peanut may be rotationally grazed with greater flexibility than most tropical forage grasses. Recommended pre-grazing CHs are within 13 and 18 cm, and post-grazing heights between 40 and 60% of the pre-grazing height.

This experiment was conducted to study the long-term effect of soil management treatments on crop yields, sustainability yield indices (SYI) and soil fertility in rainfed semi-arid tropical Alfisol at Hayathnagar Research Farm, Hyderabad, India, during the period 1995 to 2009. The experiment was conducted in a split–split plot design with conventional tillage (CT) and minimum tillage (MT) as main factors, surface application of sorghum stover @ 2 t ha−1 (SS), fresh Gliricidia loppings @ 2 t ha−1 (GL) and ‘no’ residue (NR) as sub-factors and levels of N viz. 0 (N0), 30 (N30), 60 (N60) and 90 (N90) kg N ha−1 as sub–sub factors in a castor–sorghum two-year rotation. On an average, CT maintained 30.4 and 57.0% higher grain yields of sorghum and castor, respectively, over MT. Between two residues, GL performed well in both the crops. The highest yields of sorghum (1425 kg ha−1) and castor (876 kg ha−1) were recorded at 90 kg N ha−1. CT maintained higher SYI of 0.44 compared to MT (0.38) and higher agronomic efficiency (AE) of 13.5 and 6.76 kg grain kg−1 N for sorghum and castor crop, respectively. Use of crop residue as mulch had an advantage in increasing the yield of both the crops with increase in rainfall under CT even without N application (control), probably by making the soil more receptive to water infiltration, better moisture storage and by reducing the evaporative losses. Using response functions, the optimum fertilizer N requirement was also computed for a given set of tillage and residue combinations. The revised optimum fertilizer N doses for sorghum and castor varied from 45 to 56 kg ha−1 and 46 to 74 kg ha−1, respectively, under different tillage and residue combinations and could be recommended depending upon the soil management practices.

A uniformity trial was carried out at Banting, Selangor in West Malaysia to estimate optimal sampling rates for determining foliar nutrient contents of oil palms. The results suggest that the unit for sampling in this area is greater than 10 acres but less than 50. A comparison of the results with those obtained in Nigeria shows a large measure of agreement. Factors concerned in choosing a sampling rate are discussed. With the information available a rate of 2–3 per cent appears adequate.

The effects of planting potato tubers on four different sides of two ridge orientations was investigated. Soil temperature was coolest on the northern side, followed by the western, eastern and southern sides. Fifty percent emergence took place in 24, 42 and 49 days for tubers planted on the northern, western and eastern sides, respectively. Only 22% of tubers planted on the southern side emerged. The best yield and quality was obtained by planting on the northern side, followed successively by the eastern, western and southern sides of the ridge.

Three seasons of on-farm experimentation to develop potato production from botanical or true potato seed (TPS) under cool fertile conditions in West Java, Indonesia, are described. Twenty-three farmers experimented with two production systems: use of transplants, and use of seedling tubers produced in nursery beds. There was little yield difference between the systems, but an apparent progeny × system × season interaction was observed. All progenies were more resistant to late blight than the present cultivars grown from tubers. Appropriate matching of progeny and system gave seed of comparable quality with, but total yields slightly less than, certified imported seed of cv. Granola. Ware quality was slightly better than that of cv. Granola. Production costs were markedly less than for a tuber crop, making TPS ideal for small, resource-poor farmers.

Phosphorus, followed by potassium, were the plant nutrients that most limited yields during the third decade of a long-term fertilizer experiment on groundnut, maize and cassava conducted on an Ultisol in Ghana. Application of sulphate of ammonia significantly decreased soil pH, thus reducing crop yields. Superphosphate or mulch applied alone consistently increased the yields of all three crops. Application of potash increased the yield of cassava throughout the cropping period, but the potash × mulch interaction depressed yields in two of the three cropping seasons. Use of crop rotation, grass mulch and fertilizer, including small amounts of lime, enabled crop yields and soil fertility to be maintained at a fairly high level under continuous cropping.

The effects of plant population on the yields of four commercially important Malawian groundnut cultivars have been investigated. Pod number per plant was found to be the most variable component, bearing an inverse relationship to plant density. Kernel weight and shelling percentage were low at reduced populations, and yields and kernel size declined at very high populations. The effect of plant habit upon spacing requirement is discussed and recommendations are made.

The changes taking place in the mixed farming systems of northwest Syria were examined by re-visiting, in 1996 and 2000, five villages along a rainfall gradient. The villages had been surveyed first in 1977–79. In those villages with moderate rainfall, intensification of crop production, namely a trend towards cereal monoculture and the planting of tree crops, did not lead to specialization in cropping at the expense of sheep ownership. In contrast, households in the areas too dry for most rainfed crops except barley (Hordeum vulgare) were more likely to sell their sheep because they depended heavily on off-farm income. Increases in crop yields were found but these only benefited the families in villages in the higher rainfall zones. Conversely, with the exception of ewe fertility, there was little evidence of improvements in sheep productivity. The mixed farming systems in the five villages sampled are still passing through a period of transition, and the cropping component will undoubtedly continue to change. This is less likely to happen to the small ruminant component in the near future unless the sector is given higher priority in national policy. As a strategy to increase feed production and balance the crop rotations, the prospects for closer crop/livestock integration at the farm level are limited by the many difficulties associated with the introduction of leguminous pasture and forage crops.

The results of a survey showed that one of the most critical constraints in sesame production in southern Tanzania is sesame flea beetle (Alocypha bimaculata, Jacoby). Local methods used by farmers to control, avoid or compensate for the damage caused by flea beetles were identified. Farmers regarded resistance against the flea beetle as a very desirable objective in a sesame breeding programme, but a number of other important characteristics, such as disease and drought resistance, was also mentioned. At three locations in southern Tanzania twenty sesame varieties were screened for resistance to flea beetles by counting the number of surviving plants at the 1–2 true pairs of leaves growth stage. The results suggest that there were significant differences between varieties in terms of their susceptibility to this pest, which suggests that a resistance breeding programme may be successful.

The questions and design of pasture research in tropical Australia and the resulting technologies address problems encountered in the prevailing extensive beef-production systems. In African pastoral systems, forage resource use is more intensive and complex, and production aims are manifold. An example of applied research in central Nigeria illustrates the usefulness of certain components of Australian pasture technology but the need to adapt them, particularly with respect to pasture utilization and management, within trials deliberately designed to address the differing problems in the local pastoral system.

Increasing yields in farmer fields is a priority to address increasing food demands. The study was conducted within four wheat-growing areas in Ethiopia: Debre Birhan, Hosaina, Sinana and Maychew. The objectives were to identify (1) best-bet soil fertility management options based on agronomic performance and economic evaluation and (2) key yield-reducing factors in farmer fields based on an agronomic survey among 55 participating farmers. Two types of on-farm experiments were conducted: researcher-managed trials that tested combinations of nutrients, including micronutrients, organic resources or both over two cropping seasons and farmer-managed trials comparing ‘improved practice’ against ‘farmer’s practice’. Fertilizer treatment affected wheat productivity in Debre Birhan (p < 0.01), a site limited in sulphur. Here, full NPK increased yields over the control (p < 0.05), whereas a combination of NPK and manure was better than the application of manure as the only source of added nutrients (p < 0.05). Applying half the recommended NPK with micronutrients and manure achieved similar yields as the full fertilizer treatment. In Hosaina, treatment had no significant effect on wheat productivity, although a combination of NPK and zinc resulted in an additional 26–57% yield relative to the other treatments. In Maychew, a significant treatment effect (p < 0.05) was observed. Here, the treatment with lower rates of nitrogen and phosphorous had lower yields than the full NPK treatment. A significant effect of plant densities on on-farm productivity was also observed. We conclude that although nutrient management including use of micronutrients is important in specific cases, investments to optimize plant densities have a huge potential to increase food productivity.

Despite tremendous efforts made in agricultural sectors in sub-Saharan Africa in the last two decades, fruits production and consumption to reduce malnutrition and chronic diseases remain low and have received less attention. Moreover, our knowledge of the current production situation and options for improvement are still limited. In this study, we investigated citrus farming systems and production bottlenecks to identify leverage points for intensification of smallholder citrus farming systems in Benin. We provided a typology of citrus orchards based on 17 quantitative and qualitative variables using Factor Analysis of Mixed Data combined with Hierarchical Cluster Analysis. The typology revealed four categories of citrus farms based on biophysical resources, socioeconomic resources and system management practices. Categories 1 and 2 included farms characterised by less diversified cropping systems with non-recommended management practices. Orchard categories 3 and 4 included farms with high varietal diversity and improved management practices. However, farmers of category 4 neglected staking and digging practices. The inadequate farming practices explained some of the production bottlenecks, which were orchard-type dependent. We discussed the implications of our findings and suggested a number of policy and strategic decisions as well as research and development actions for improving citrus production in Benin.

A highly diverse range of plantain varieties are cropped in West and Central Africa, and it is essential to enhance knowledge on this diversity to support farmers in their varietal choices. This study aims at proposing a new way to describe a panel of plantain varieties, based on their agronomic and usage potential. The agronomic trait values of nine plantain varieties, including five traditional varieties (Batard, Big Ebanga, Essong, French Clair and Mbouroukou n°3) representative of the diversity of the plantain group, and four plantain-like hybrids (CRBP39, D248, D535 and FHIA21) were recorded at flowering and harvest. The findings revealed very marked inter-varietal variations, in line with the features of plantain morphotaxonomic subgroups, as well as very high intra-varietal variations, especially for the Essong variety. This extent of intra-varietal variation suggests that traditional plantain multiplication methods could favour the emergence of mutations in plantain varieties and hence of high intra-varietal variability. Finally, the monitored agronomic traits were integrated as agronomic and usage potential indicators per variety and morphotaxonomic subgroup, which could support decision-making on plantain varieties.

Optimisation of fertiliser use and site-specific nutrient management are increasingly becoming critical because of the growing need to balance agricultural productivity with the growing demand for food and environmental concerns. Trials to determine responses of crops to fertilisers have been widely conducted in sub-Saharan Africa (SSA) with increasing emphasis on the development of economically optimum rates (EORs). Computation of EORs depends on accurate estimation of both the optimum nutrient rate and the agronomic maximum yield response; however, estimation of nutrient-response parameters and EORs is beset by a number of problems. Therefore, the objectives of this paper were to (1) point out common problems in the development and use of nutrient dose-response models and (2) provide corrective measures to facilitate future trial design and data analysis. This review outlines the underlying assumptions, strengths and limitations of the various response functions in order to facilitate informed choices by practitioners. Using specific examples, it also shows that (1) the commonly used trial designs do not allow examination of interactions between two or more nutrients and (2) trial designs with ≤5 nutrient levels and wide spacing between the levels result in large uncertainty in dose-response parameters. The key recommendations emerging from the review are as follows: (1) factorial designs and response surface models should be used more widely to address interactions between nutrients; (2) a minimum of six carefully spaced nutrient levels should be used to correctly estimate dose-response parameters; and (3) when locating field trials, Reference Soil Groups and cropping history should be carefully considered to produce site-specific EORs.

Pods of vegetable cowpea Vigna unguiculata Walp. cv. Dinner were harvested at various developmental stages and their biochemical components and other characteristics analysed in two years. Pod length, percentage dry matter and starch, fresh and dry weights and total yield of sugar and starch per unit area increased with age. The percentage total yield of sugars was greatest in pods aged between 11 and 13 days. Vitamin C, total acidity, crude fibre and crude protein percentage decreased with age. Content of minerals except iron also decreased with age of pods. Magnesium, phosphorus, potassium, manganese and copper contents were greater in 1977 than in 1979 but iron and calcium contents were smaller. The vegetable cowpea pods were a rich source of calcium, magnesium, potassium and iron. Pods harvested between 7 and 10 days after flowering were crisply tasty and high in nutrients and therefore nutritionally the most acceptable for consumption.