Common bean (Phaseolus vulgaris L.) is the most important food legume for human consumption. Drought stress is the major abiotic stress limitation of bean yields in smallholder farming systems worldwide. The current work aimed to determine the role of enhanced photosynthate mobilization to improve adaptation to intermittent and terminal drought stress and to identify a few key adaptive traits that can be used for developing drought-resistant genotypes. Field studies were conducted over three seasons at Centro Internacional de Agricultura Tropical, Palmira, Colombia to determine genotypic differences in adaptation to intermittent (two seasons) and terminal (one season) drought stress compared with irrigated conditions. A set of 36 genotypes, including 33 common bean, two wild bean and one cowpea were evaluated using a 6 × 6 lattice design under irrigated and rainfed field conditions. Three common bean elite lines (NCB 226, SEN 56, SER 125) were identified with superior levels of adaptation to both intermittent and terminal drought stress conditions. The greater performance of these lines under drought stress was associated with their ability to remobilize photosynthate to increase grain yield based on higher values of harvest index, pod harvest index, leaf area index and canopy biomass. Two wild bean germplasm accessions (G 19902, G 24390) showed very poor adaptation to both types of drought stress. One small-seeded black line (NCB 226) was superior in combining greater values of canopy biomass with greater ability to mobilize photosynthates to grain under both types of drought stress. Two small-seeded red lines (SER 78, SER 125) seem to combine the desirable traits of enhanced mobilization of photosynthates to seed with effective use of water through canopy cooling under terminal drought stress. Pod harvest index showed significant positive association with grain yield under both types of drought stress and this trait can be used by breeders as an additional selection method to grain yield in evaluation of breeding populations for both types of drought stress.

Cash-constrained farmers who cannot afford herbicides and mineral fertilizers may incorporate green manure cover crops (GMCCs) as relay crops to aid in management of weeds and nitrogen in maize systems under conservation agriculture in cases where rotations are a challenge. An experiment was conducted at two sites with contrasting soil types, University of Zimbabwe farm (clay) and Domboshawa Training Centre (sandy) to investigate the effects of maize/velvet bean intercropping at 8 weeks after planting maize (WAPM), applying different fertilizer rates and exploring their interactive effects on weed composition, maize productivity and biomass production [total maize non-cob biomass (stover) plus GMCC biomass]. The performance of the system depended largely on the amount of rainfall received within and across the seasons, sites and their interaction; also on the amount of fertilizer applied. Generally, biomass yields attained by velvet bean [Mucuna pruriens L. (DC.)] were lower than reported previously. Maize grain yield and weed diversity were higher in treatments with higher fertilizer rates, reaching up to 5·1 t/ha and 1·39, respectively. Generally, the highest weed diversity and highest maize grain yield values were observed in maize/velvet bean combinations and higher fertilizer rates (i.e. 0·27 and 4·8 t/ha, respectively) in the sandy soil. Higher fertilizer rates resulted in greater maize stover yield and this contributed greatly to the biomass productivity of the system in the sandy soil in the 2012/13 season, while the high biomass productivity observed in velvet bean in the clay site in the final season contributed significantly to productivity. Maize productivity was not affected by velvet bean introduced at 8 WAPM in any of the seasons. The present study showed that relay cropping velvet bean as late as 8 WAPM and onwards has potential to increase biomass production without compromising maize yields. However, planting it as late as 8 WAPM results in reduced productivity due to reduced moisture availability.

A great many plantain varieties are cropped in West and Central Africa, and there is a lack of information about their production potential and suitability for cropping system environments. To obtain benchmark data for the production potential of plantain varieties, experimental and modelling approaches were combined to determine intrinsic growth parameters and to increase understanding of factors affecting yield. Five real plantains commonly cropped in Cameroon and representative of plantain group diversity (Batard, Big Ebanga, Essong, French clair and Mbouroukou n°3) and four plantain-like hybrids (CRBP39, D248, D535 and FHIA21) were studied. A process-based growth model (the AAB model) was developed that accounts for specific characteristics of the plantain crop that includes parameters affecting growth, development and yield. Varietal-specific parameters were determined in a field experiment conducted under nearly non-limiting production conditions while general parameters were drawn from the literature. Parameters describing the conversion of intercepted radiation into dry matter were evaluated by model fitting. Photosynthetic efficiency was significantly higher for real plantains than for plantain-like hybrids. The model realistically simulated development, growth and bunch production for five varieties. These results are the first step in developing a useful tool for assessing the suitability of plantain varieties to different environments. The current study highlights the need for greater knowledge of plantain physiology in order to better model plantain growth and develop variety-specific production approaches.

Controlled irrigation during the dry period associated with adequate nitrogen (N), phosphorous (P) and potassium (K) fertilization led to the accumulation of biochemical compounds in coffee beans considered as positive precursors of beverage quality. Adult plants of coffee (Coffea arabica ‘Rubi’) were cultivated using different water regimes (WR) and fertilization conditions under the dry climate of the Brazilian Cerrado. Coffee-bean physical characteristics were evaluated as well as biochemical composition by near-infrared analysis. The K treatment mostly affected bean biochemistry, lipid and chlorogenic acid (CGA) contents, which increased with increasing amounts of fertilizer. Caffeine contents increased with higher amounts of N, but no significant effects of P treatment on bean biochemical composition were observed. Sucrose and total lipid contents always appeared higher in beans of non-irrigated plants than those beans from plants grown with continuous irrigation. In contrast, caffeine and CGA contents were higher in beans of irrigated as compared with non-irrigated plants. For the first time, the current results showed that controlled management of irrigation during the dry period associated with reasonable NPK fertilization led to the accumulation of biochemical compounds in coffee beans considered as positive precursors of beverage quality.

Sweetpotato breeding requires at least 5 years to obtain an advanced breeding clone for further testing with the goal of cultivar release. An accelerated breeding scheme (ABS) can be feasible if the genotype × year interaction is low. The objectives of the present study were to describe an ABS for sweetpotato and to investigate the efficiency of this breeding scheme for selecting high-yielding and well-adapted orange-fleshed sweetpotato (OFSP) cultivars with high β-carotene (BC) content. More than 198 500 seeds from two crossing blocks were germinated and rapidly multiplied for evaluation in observation trials at four breeding locations in Mozambique. Breeding clones with storage root yields above 10 t/ha were advanced to preliminary and advanced yield trials across four sites and for 3 years. As a result, 64 high-yielding OFSP breeding clones were selected and evaluated in four mega-environments following a randomized complete block design with three replicates at Angónia, Chókwè, Gurúè and Umbelúzi. Data from multi-environment trials were subjected to single site and combined analysis of variance as well as to stability analysis. The genotype × environment interaction was highly significant for storage root and vine yields, dry matter (DM) and BC content. Storage root yield and DM content for 15 OFSP breeding clones ranged from 14·9 to 27·1 t/ha and from 24·8 to 32·8%, respectively. BC content, iron and zinc ranged from 5·9 to 38·4, 1·6 to 2·1 and 1·1 to 1·5 mg/100 g dry weight, respectively. The OFSP breeding clones also met the culinary tastes required by local consumers in Mozambique. The proposed ABS seems to be an attractive scheme for genetic enhancement of sweetpotato.

The goal of the present study was to improve the CERES-wheat model simulation of grain protein concentration (GPC) for winter durum wheat and to use the model as a basis for the development of a GPC Simplified Forecasting Index (SFIpro). The performances of CERES-wheat, which is one of the most widespread crop simulation models, with (i) its standard GPC routine and (ii) a novel equation developed to improve the model GPC simulation for durum wheat, were assessed through comparison with field data. Subsequently, CERES-wheat was run for a 56-year period in order to identify the most important status and forcing variables affecting GPC simulation. The number of dry days during the early growth stages and the leaf area index (LAI; green leaf area per unit ground surface area) at heading stage (LAI5) were identified as the main variables positively correlated with CERES-wheat predicted GPC, and so included in the SFIpro. At validation against observed data SFIpro was found to perform differently on the basis of observed plant LAI. In fact, SFIpro was able to forecast GPC variability for intermediate values of LAI5 ranging from 1 to 2, while it totally failed when LAI5 was outside this range (LAI5 < 1 or LAI5 > 2). The results suggest that the relationship between LAI and GPC is not linear and that the model assumptions for GPC simulation in CERES-wheat are only partially confirmed, being valid for an intermediate range of LAI.

Analysing the stability and adaptation of cultivars to different environments is always necessary before recommending them for planting on large areas. Additive main effects and multiplicative interaction (AMMI) models have been used to analyse genotype-by-environment interactions (G × E). AMMI models require data with homogeneous variance, normal errors and additive effects. However, agronomic data do not always conform to these statistical assumptions. The objective of the present study was to analyse G × E interactions for severity and incidence of grey leaf spot, a foliar disease in maize caused by Cercospora zeae-maydis, using a generalized AMMI model. Data were collected and evaluated for 36 maize cultivars from experiments carried out in nine Brazilian regions in 2010/11 by the Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA – Milho e Sorgo). Only two of three stable genotypes defined by a quasi-likelihood model with a logistic link function could be recommended for their desirable agronomic characteristics. Four growing locations in which the genotypes were stable were identified, but in only one of these was stability associated with very severe grey leaf spot disease. Cultivars adapted to specific locations with low percentage disease severity were also identified.

Recently, organic farming systems have attracted the attention of consumers because of their low environmental impact. Organic agriculture is a valid alternative to conventional farming and ancient wheat, such as KAMUT® khorasan wheat (T. turgidum ssp. turanicum), has emerged as an industry leader for its nutritional and functional properties (anti-inflammatory, antioxidant and prebiotic).

The aim of the present study was to evaluate environmental effects on the quality of KAMUT® khorasan grains harvested in the last two decades (1989–2012) on one farm in Montana (USA), through the evaluation of phytochemical accumulation. Results revealed high variability in the amounts of macronutrients and nutraceuticals. In particular, from 1989 to 2012, there was a decreasing trend in starch content (ranging from 70·87 to 50·54/100 g) and amylose (from 41·48 to 31·46% of total starch) with a slight increase of insoluble dietary fibre (from 12·14 to 17·75/100 g). The soluble dietary fibre content varied among the years of cultivation even if the general trend remained constant (4·57–2·82/100 g). High variability of total polyphenols content was observed with the free soluble fraction present at lower levels than bound polyphenols (BP). Moreover, an inverse correlation between free and BP was observed. The results obtained in the present study show that the influence of environmental conditions plays a fundamental role in the accumulation of primary and secondary metabolites in wheat kernels and strongly modulate the nutritional and nutraceutical value of flour.

APETALA2/ethylene-responsive factor (AP2/ERF) family transcription factors play a vital role in plant growth and in response to hormones and abiotic stresses. In the current research, it is reported that OsDERF2, one of the drought-responsive ERF, is a member of the DREB sub-family. OsDERF2 is a nuclear-localized protein and has transcriptional activity in yeast. Expression of OsDERF2 was induced by drought and inhibited by abscisic acid (ABA). However, OsDERF2 RNA interference (RNAi) knock-down transgenic lines enhanced tolerance to drought stress at seedling stage and were much more sensitive to ABA treatment, which may result from the increased ABA level in vivo. The basic leucine zipper (bZIP) transcription factor family plays an important role in the ABA signalling pathway of abiotic stress. Quantitative real-time polymerase chain reaction analysis revealed that the bZIP family gene OsbZIP20 and ABA-response gene OsABA45 were up-regulated 25 times and 120 times, respectively, in OsDERF2 RNAi knock-down lines under drought stress, which were up-regulated five and seven times in wild type under drought stress. The current data reveal that OsDERF2 negatively modulates drought stress response in an ABA-mediated pathway through regulating gene expression of other ABA-response transcription factors.

Physiological traits can be used to improve the efficiency of selecting suitable genotypes to grow under nitrogen (N) limitation. The objective of the current study was to investigate the relationship between physiological characteristics and storage root yield of three cassava genotypes under three rates of N fertilizer. The experiments were conducted from 2014 to 2016 at farm fields in Thailand. A split-plot randomized complete block design with four replications was used. Three different rates of N fertilizer, i.e., 46·9, 90·0 and 133·2 kg N/ha and three cassava genotypes, Rayong 9, Rayong 11 and Kasetsart 50, were used. Kasetsart 50 had the highest mean performance for most crop traits. Growth rate of stem (SGR), storage root (SRGR) and crop (CGR) during 180–210 days after planting (DAP) and leaf area index (LAI) at 120 DAP were related to storage root dry weight for all three rates of N fertilizer. Storage root growth during 90–120 DAP, CGR during 180–210 DAP and specific leaf area (SLA) at 210 DAP contributed most to storage root dry weight of the three genotypes grown at 46·9 kg N/ha, while the combination of SRGR during 90–120 DAP, SRGR during 180–210 DAP, LAI at 210 DAP and SLA at 210 DAP was best for N fertilizer at 90·0 kg N/ha and the combination of leaf growth rate (LGR) during 180–210 DAP and LAI at 210 DAP was best for N fertilizer at 133·2 kg N/ha.

Extensive sheep and goat farming is common in the rangelands of Gökçeada Island, NW Turkey. The aim of the current study was to investigate the behaviour of indigenous Gökçeada sheep over these rangelands and factors influencing their behavioural characteristics. Grubbing (with chisel ploughing to a depth of 20 cm), burning (the entire top part of plants) and cutting (10–15 cm stalk on the surface of the soil) were carried out on selected rangeland to reduce prickly burnet (Sarcopoterium spinosum (L.) Spach) from the vegetative covering, then forage crop seeds were sown to improve plant cover. Forty head of Gökçeada-bred sheep were placed in eight fenced plots (half seeded, half unseeded) on reclaimed and natural rangeland for 2 years. Sheep behaviour was observed for a period of 1 year. Each plot was arranged with a stocking rate of 2·67 sheep/ha and contained five sheep that grazed freely within each plot. Sheep behaviour was observed diurnally through direct observation by time sampling (10 min) and continuous sampling methods. During the period of 1 year, the observed sheep spent an average of 0·53 of their time grazing in daylight, 0·30 of their time in rangelands on other activities and 0·17 in the paddocks. Significant differences were observed in the time of grazing, resting, locomotion and rumination by season. The highest grazing ratio was noticed in spring while the lowest was in summer. Sheep exhibited walking behaviour 10·6 times/day. The sheep mostly (0·66) grazed on prickly burnet throughout the year although, when available, they tended to prefer herbaceous plants. The behaviour of sheep in the two natural (unreclaimed) plots was significantly different from those placed in other plots, mainly due to the mass of prickly burnet shrub found in the natural plots.

To assess the impact of farm management on herd fertility, a survey of 105 beef farms in Northern Ireland was conducted to establish the relationship between management variables and fertility. Each herd's average calving interval (CI) and the proportion of cows with a CI > 450 days (extended calving interval, ECI) was calculated to establish herd fertility. The relationship between each response variable (CI and proportion ECI) and each explanatory variable (respondents’ answers to questionnaire) was examined using univariate linear regression analyses. All response variables found to be associated with the explanatory variables were modelled against each group in turn using a fully automated multivariate stepwise regression algorithm employing the method of forward selection with backward elimination. The optimum 365-day CI and a proportion of 0 cows per hundred calved ECI targets were not widely attained in the current study. The distribution of CI and proportion ECI in the current study suggests more realistic targets would be a 379-day CI and 5 cows per hundred calved with ECI in commercial beef breeding herds. Six management factors were found to be associated with herd fertility: herd vaccination, bull selection, fertility management, breeding female management, perception of extension service (rural education provided by the government) and record keeping. It was found that respondents who vaccinated cows had a reduction of 5 cows per hundred calved in the proportion of cows with ECI, and as the number of vaccines administered to a cow increased, the CI decreased. Regular vaccination of breeding bulls was associated with a 9-day reduction in CI. Bull selection strategy had several associations with herd fertility; most notable was that respondents who used visual selection rather than estimated breeding values (EBVs) to select bulls were found to have a 15-day longer CI and 7 cows per hundred calved higher proportion of cows with ECI. For each 0·01 increase in the proportion of cows served by artificial insemination, CI increased by 0·16 days. Respondents who rated their beef breeding herd fertility as ‘very good’ had lower ECI and CI than those who rated beef breeding herd fertility as poor or satisfactory. Condition scoring of cows at weaning lowered ECI by 5 cows per hundred calved. Those who perceived the extension service to be very useful had the lowest CI and lowest ECI. Respondents who did not keep a record of CI to assess herd fertility had an 11-day longer CI and 6 cows per hundred calved higher proportion ECI than those who did not. In conclusion, the survey found a number of important variables linked to improved fertility including selecting sires based on EBVs and using a robust vaccination programme.