Legumes are essential to meet nutrition need of growing population in Afghanistan but have low productivity under the farmer practices. With an aim to introduce improved varieties of chickpea (Cicer arietinum) and mung bean (Vigna radiata) along with associated cultivation practices, a number of on-farm demonstration trials were conducted in eight districts covering three provinces to assess their performance in comparison with local practices. The data or information generation from on-farm trials is routine but remains unutilized under the commonly used analysis based on frequentist approach. This study makes use of such prior information to widen the statistical inference framework using a Bayesian approach (BA) for analysing any future on-farm trials. The statistical analysis evaluated the mean performance of the improved and local production packages and risks associated with them to meet a given target. Evaluated at the two districts during 2012, the improved variety of chickpea (Madad) yielded higher than the farmer variety (2.25–2.40 vs. 1.93–1.94 Mg/ha), while that of mung bean (Mash 2008) yielded higher than the farmer variety (1.22–1.24 vs. 0.93–0.94 Mg/ha), both with high probability. The stochastic dominance analysis showed that the recommended package with improved variety Madad has 95% probability of achieving a target of 2 Mg/ha while such a target for local practice was around its one-third when cultivated in Baghlan-e-sannati district. Crossover in the risk curves helped to identify and quantify the region specific risk to meet a given target. BA is then recommended in the analysis of on-farm trials data.

The effect of managing hedgerow foliage for mulch and fodder in Leucaena leucocephala and Gliricidia sepium alley farming systems on maize grain yield and soil chemical characteristics was studied in on-station and on-farm experiments in southwestern Nigeria. Yields increased as the proportion of mulch applied increased but the extra increases obtained when more than half the foliage was applied as mulch were relatively small, suggesting that half the foliage may be removed as feed without detrimental effect. Soil organic carbon, nitrogen and available phosphorus tended to increase with increasing proportion of prunings applied as mulch.

Follaje para ‘mulch’ y forraje en la agricultura de sendero

The production of maize in every second inter-row of first and second ratoon sugar cane was studied in four locations in Mauritius in 1974, in trials based on combinations of three maize densities and three fertilizer levels. Analysis of the data showed that intercropping sugar cane with maize had no adverse effects on cane and sugar yields, and suggested that planting an early-maturing maize amongst the cane at a density of 19,000 plants, with 76 kg N, 38 kg P2O5, 62 kg K2O/ha, was the most profitable method under Mauritian conditions.

Sucrose yield in sugarcane is a complex process regulated by both environmental and endogenous factors. However, the metabolic balance driving vegetative growth and sucrose accumulation remains poorly understood. Herein, we carried out a comprehensive assessment of carbohydrate dynamics throughout the crop cycle in two sugarcane varieties varying in biomass production, evaluating the carbon metabolism in both leaves and stalks. Our data revealed that the decline in photosynthetic rates during sugarcane maturation is associated not only to accumulation of sugars in leaves but also due to stomatal and non-stomatal limitations. We found that metabolic processes in leaves and stalks were intrinsically linked. While IACSP94-2094 had higher stalk sucrose concentration than IACSP95-5000, this latter produced more biomass. Compared to IACSP95-5000, IACSP94-2094 showed higher sucrose phosphate synthase (SPS) activity in leaves and stalks, along with lower soluble acid invertase (SAI) activity in leaves during the maximum growth stage. Interestingly, IACSP94-2094 also exhibited higher stalk SPS activity and lower stalk SAI activity than IACSP95-5000 during maturation. High biomass production by IACSP95-5000 was associated with higher sucrose synthase (SuSy) and SAI activity in leaves and higher SuSy and soluble neutral invertase (SNI) activity in stalks when compared to IACSP94-2094 during the maximum growth. Despite the contrasting strategies, both varieties displayed similar total sucrose yield, a balance between sucrose concentration and biomass production. This phenomenon implies the presence of a compensatory mechanism in sugarcane, with high biomass production compensating low sucrose accumulation and vice versa.

Agricultural production on the Mahafaly Plateau in SW-Madagascar has traditionally been based on subsistence rain-fed agriculture, with yields declining as a result of low soil fertility, recurrent droughts, and erratic rainfall. Market-oriented vegetable production in this area may help households improve their nutrition and diversify their income. In field trials between the 2013 and 2016 dry cropping seasons, the feasibility of carrot (Daucus carota L.) and onion (Allium cepa L.) production was assessed by testing effects of manure and charcoal amendments, shading, and seed quality on yields. Due to damage caused by cyclones and strong winds, only data from 2013 and 2016 are reported in this paper. Additionally to the field experiments, effects of salinity on seed germination were also examined under laboratory conditions and in the field. Carrot dry matter (DM) yields were 0.24 to 2.76 t·ha−1 while those of onion were 0.15 to 0.99 t·ha−1 DM. While the combination of manure and charcoal application had only minor effects on crop growth, manure alone increased carrot yield by 26% across years. After one cropping season, manure application reduced soil pH from 9.0 to 8.6 and increased soil Corg from 0.87 to 1.76%, N from 0.08 to 0.14%, and P from 10.6 to 15.1 mg·kg−1. Shading reduced carrot yields from 0.87 to 0.58 t·ha−1 DM in 2013 and from 1.87 to 0.85 t·ha−1 DM in 2016, but increased onion yield in 2013 from 0.24 to 0.62 t·ha−1 DM. Carrot seed procured locally performed better in the field than seed imported from the capital which translated into differences in seedling emergence. Saline irrigation water (electrical conductivity = 7.03 mS·cm−1) reduced seedling emergence rate of carrot from 73 to 20% and for onion from 44 to 28% and unprimed seeds performed better than primed ones. Using shading during the dry season is not advisable for carrot and onion production, but improving seed quality and targeted use of soil amendments (time of manure application, manure quality) may enhance vegetable yields.

N-enriched biochar can increase the accumulation of carbon (C), nitrogen (N), phosphorus (P), and biomass in rice plants. On the other hand, the biomass and C, N, and P contents of plant organs are important indicators to reflect plant C, N, and P storages. We established control, 4 t ha−1, and 8 t ha−1 N-enriched biochar treatment plots in a subtropical paddy field in China to investigate the effect of these treatments on C, N, and P storages, ecological stoichiometry in various rice plant organs, and their relationships with edaphic factors. The application of N-enriched biochar increased the biomass and storages of C, N, and P in rice roots, stems, leaves, and grains, mainly at 4 t ha−1. The application of N-enriched biochar decreased the C/N and C/P ratios of rice organs, but increased their N/P ratio. Changes in C/N were mainly due to the changes in storage, while N/P was positively correlated with N storage of stems, leaves, and grains and negatively correlated with P storage in roots. Pearson’s correlation analysis revealed that pH was negatively correlated, and soil N content was positively correlated with P storage in various organs of rice. In addition, soil P content and chlorophyll were positively correlated with N storage. In conclusion, we found that the application of N-enriched biochar improved plant N and P storage and stoichiometrical relations among rice organs.

Water deficiency is one of the most severe abiotic stresses in rainfed dry lands and limits crop productivity. Exogenous applications of salicylic acid (SA) have been applied to mitigate the adverse effects of water-deficit stresses, but the relative efficacy of different derivatives of SA in enhancing water-deficit tolerance along with the underlying physio-biochemical mechanism and yield of crops is not well documented. Field experiments were conducted to ascertain the relative efficacy of exogenous application of three plant bioregulators (PBRs) [SA, thiosalicylic acid and 5-sulfosalicylic acid (SSA)], each at three concentrations (0.5, 1.0 and 1.5 mM), on the growth, physio-biochemical characteristics and yield of cluster bean under rainfed conditions. Based on a 2-year field experiment, the application of PBRs enhanced yield (from 8 to 16%). The yield enhancement with the application of PBRs was associated with elevated water content (from 9 to 17%), membrane stability (from 12 to 18%) and antioxidant enzyme activity (from 12 to 33%) and reduced lipid peroxidation (from −15 to −34%) in leaves. The effects of PBRs were conditionally type and concentration dependent. The application of SSA at a rate of 1 mM was more effective in enhancing water-deficit tolerance and improving the yield of cluster bean under water shortage conditions. This study provides empirical evidence of the potential for the application of SA and its derivatives to enhance crop yields under drought conditions. The results have direct implications for sustainable crop production for similar regions of the world facing water deficits.

The problems resulting from genotype × environment interactions are discussed, giving an example where the application of statistical techniques to maize breeding makes it possible to assess the effects of such interactions. A method of maize breeding is proposed which enables a number of objectives to be achieved from a single breeding programme.

In researcher-designed, farmer-managed experiments with cabbage and hot pepper, ground seashells (GSS) were compared with low-grade phosphate lime (LGP) at rates of 0, 2.5, 5, 7.5 or 10 t ha−1. A randomized complete block design, with replicates spread over different farms, was used. Liming with GSS or LGP at 10 t ha−1 increased cabbage yield from 0.5 t ha−1 without liming to 15.0 and 5.3 t ha−1 respectively. Hot pepper yield was increased from 2.1 t ha−1 without liming to 3.2 t ha−1 at the three highest rates of GSS and LGP. Application of GSS increased the pH, reduced exchangeable acidity and increased the extractable Ca content of the soil. Partial budget analyses revealed that cabbage and pepper growers obtained highest returns with GSS at 10 and 5 t ha−1 respectively.

The present study evaluated the pest constraints of an innovative crop management system in Cameroon involving conservation tillage and direct seeding mulch-based strategies. We hypothesized that the presence of mulch (i) would support a higher density of phytophagous arthropods particularly millipedes as well as pathogenic fungi that cause severe damage to cotton seedlings and (ii) would reduce early aphid infestations. The impact of two cover-crop mulches Calopogonium mucunoides and Brachiaria ruziziensis on the vigour of seedling cotton stands and arthropod damage was assessed in two independent field experiments conducted in 2001 and 2002 respectively. In both experiments the presence of mulch negatively affected cotton seedling stand by 13–14% compared to non-mulched plots and the proportion of damaged seedlings was higher in mulched than in non-mulched plots supporting the hypothesis that mulch favoured soil pest damage. In both experiments insecticidal seed dressing increased the seedling stand and the number of dead millipedes collected and fungicide had little or no effect on seedling stand and vigour. It was however observed in 2002 that the fungicide seed dressing had a positive effect on seedling stand in non-mulched plots but not in mulched plots suggesting that fungi may have been naturally inhibited by B. ruziziensis mulch. The dynamics of aphid colonization was not influenced by the presence of mulch. In 2001 taller seedlings were found in mulched than non-mulched plots probably due to greater water and nutrient availability in C. mucunoides-mulched plots than in non-mulched plots.

On-farm research in remote areas demands methods that keep down costs and reduce the need for subsequent research and extension inputs and yet that still produce useful and sustainable recommendations. An important part of the process is to identify existing resource user groups and use them, rather than individual farmers, as a starting point for on-farm research. This approach is discussed in the context of farming systems research in the eastern hills of Nepal.

In trials with Helianthus annuus in the highlands of Kenya it appeared that the major constraints for successful utilization of sunflower for forage were: high lodging susceptibility; low DM percentage of the forage; low D-value of the forage when high yielding ( = tall) cultivars are used; and poor silage making characteristics. The proportion and quality of the stem largely governed the nutritive value of the whole plant. A reduced proportion of stem would improve all four constraints, but DM yield would also be reduced. Protein yields were highest at the beginning of flowering, but DOM yields were highest about 9 days later, towards the end of flowering. DM yields were highest towards physiological maturity of the seeds.

Many of the papers submitted to this Journal fall far short of the standard of presentation that editors are entitled to expect. This tends to sour the all-important relation between editor and author, making unnecessary work for the former and perhaps even prejudicing acceptance of the latter's paper. The author, typist, editor and copy-editor have specific roles to play in preparing copy for the compositor and this article explains those roles, in the hope that the explanation may help authors to present their papers in the correct form.

In response to the extensive development of upland rice on the hillsides of the Malagasy highlands, alternative cropping systems have been designed based on conservation agriculture (CA). As the promotion of CA in smallholder farming systems is still the subject of debate, its potential benefits for smallholder farmers require further assessment. In the context of resource-poor farmers and low-input production systems, nitrogen (N) is a major limiting nutrient. The effects of contrasted cropping systems have been studied on upland rice yield and N uptake in rainfed conditions: conventional tillage (CT) and CA with a mulch of maize or a legume (Stylosanthes or velvet bean). Decision Support Systems for Agrotechnology Transfer (DSSAT) crop growth model was used to quantify the soil N balance according to the season and the cropping system. The lowest yields were obtained in CA with a mulch of maize and were also associated with the lowest crop N uptake. Upland rice yields were higher or equivalent under CA with a legume mulch than under CT cropping systems. The supply of N was considerably higher in CA with a legume mulch than in CT, but due to higher leaching and immobilization in CA, the final contribution of N from the mulch to the crop was reduced although not negligible. DSSAT has been shown to be sufficiently robust and flexible to simulate the soil N balance in contrasting cropping systems. The challenge is now to evaluate the model in less contrasted experimental conditions in order to validate its use for N uptake and yield prediction in support to the optimization and design of new cropping systems.

A long-term field trial was conducted to determine yield trends in relation to nutrient uptake and efficiency in different rice-based cropping systems. The cropping systems had a significant effect on wet season rice yield when residues were not recycled but had no effect otherwise. Rice yield decreased after the first year of crop residue incorporation but increased every year thereafter. Rice yield was significantly affected by residual nutrients applied to dry season crops. The highest residual effect was observed in tomato and sweet pepper to which the highest nitrogen (N), phosphorus (P) and potassium (K) rates were applied. Maize, sweet pepper, and tomato responded well to NPK application, garlic had a low response and mungbean had no response. A relay crop served as a catch crop for excess nutrients and as shade to minimize sunscald effects for tomato and sweet pepper fruits.

The functional distribution of root activity was determined by selective placement of 32P at fixed positions from the base of the plant in five- and six-year-old acid lime (Kagzi Kalan) on Kama Khatta rootstock. Maximum recovery of radioactivity was observed within a 40 cm radius of the plant base and at depths of 24 cm in 1988 and 16 cm in 1989. Most root activity (75–80%) was confined within a radius of 80 cm and a depth of 16–24 cm. Application of fertilizer within this zone is therefore recommended for maximum utilization by the crop.

Actividad de las raíces en la lima acida