Data are presented from two experiments which examined the effect of three seed sizes and three within-row spacings on the bulking rate of graded potatoes from the two early mainorop varieties Pentland Crown and Maris Piper.

There were significant linear and quadratic regressions of yield on time and there were significant effects of all main treatments on the bulking rate of the crop. Differences in yield between the levels of each treatment depended upon the time of harvest and the size of tubers considered.

In laboratory tests tri-n-butyl phosphate applied by spraying as an emulsion at a rate equivalent to 0·25% of leaf fresh weight doubled the drying rate of individual S.24 perennial ryegrass leaves measured at 28 °C, relative humidity 22% and air speed 40 cm/sec. Increasing the rate of application produced no further increase in drying rate. In other experiments the same rate of application stopped respiration of leaves and no resumption of respiration was found in the subsequent 4 days. Comparisons of the dry-matter contents of leaves when removed from the plant and after being allowed to dry for 1 week at 27 °C and relative humidity 80%, indicated that inhibition of respiration resulted in large reductions in dry-matter losses. The potential value of a chemical spray which will both increase drying rate and reduce respiration as an aidto the field drying of grass crops is discussed. While it would be incautious to extrapolate from laboratory tests on single leaves to the field situation, evaluation under more practical conditions is clearly warranted.

Farmers, who have to decide which pesticide to use against a particular crop-damaging pest, need to take into account country-specific regulations (e.g. permitted levels of pesticide residues), application instructions and financial considerations. The fact that these data are stored in different locations, sometimes using different terminology or different languages, makes it difficult to gather these data and requires that farmers are familiar with the variety of terms used, which consequently hampers the efficiency and effectiveness of the decision process. To overcome these challenges, a Web application for pest control is proposed to facilitate the integration of information coming from different Internet sources and representing different terminologies by using an ontology. The application is based on a pest-control ontology (formal representations of domain knowledge that can be interpreted by computers) that accounts for various pesticide regulations of different countries to which the crop is exported. In recent years, ontologies have become a major tool for domain knowledge representation and a core component of many knowledge management systems, decision support systems and other intelligent systems, inter alia, in the context of agriculture. The pest-control ontology developed in the current research includes pest-control concepts that have yet to be covered by existing ontologies. It is demonstrated in the specific case of pepper in Israel. The ontology is expressed using Web Ontology Language (OWL) and thus can be shared on the Web and reused by other ontologies and systems. In addition, a comprehensive method for developing and evaluating agricultural ontologies is presented.

Meteorological extremes such as heatwaves and water limitations during the ripening season could negatively impact vine ecophysiology and berry metabolism resulting in lower yield per vine. This project aimed to compare two different soil managements during two growing-production seasons (2021 and 2022) with respect to control without any treatment (control). The two managements were: Zeowine (30 t/ha; a soil conditioner made with clinoptilolite and compost proceeding of industrial wine-waste) and compost (20 t/ha). The trial was organized at Col d'Orcia Estate (Montalcino, Tuscan wine region, Italy). The purpose was twofold: (1) to evaluate the effects of Zeowine treatments on leaf gas exchanges, midday stem water potential, chlorophyll fluorescence and leaf temperature (ecophysiology); and (2) to determine any repercussions on the quality of the grapes (technological and phenolics analyses). The parameters plant yield, yeast assimilable nitrogen, fractionation of anthocyanins (cyanidin, delphinidin, malvidin, peonidin and petunidin), caffeic acid, coumaric acid, gallic acid, ferulic acid, kaempferol and quercetin were also analysed. Zeowine showed higher photosynthesis, less negative midday water potential and lower leaf temperature. Essentially, no significant difference was found between the compost and the control. Furthermore, Zeowine grapevines showed higher anthocyanin accumulation and less quercetin content. In general, compost applied together with zeolite could alleviate the adverse effects of water stress and improve plant growth, yield and quality. The control management strategy proved to be the least beneficial for the well-being of the plant and the final quality of the product, confirming the need for amendments in critical years.

From 1999 to 2006, 36 field experiments were conducted in five sugar beet growing areas in Greece (Larissa, Plati, Serres, Xanthi and Orestiada) to monitor yield. Locations differed significantly regarding thermal variables during the growing season with Xanthi having the most favourable thermal conditions (Tmax, average daily maximum temperature; Tmean, average daily mean temperature; GDD, growing degree days) for sugar beet growth. From early June to the end of the harvesting campaign, successive harvests were conducted. Over the years, fresh root weight and sugar yield at the last harvest of the season (FRWLH, SYLH) did not differ significantly among locations. Also, there were no significant differences among locations regarding GDD for maximum FRW and SY (GDDMFRW, GDDMSY), with the means over location estimated at 2639·9 and 2792·5 °C, respectively. Days after seeding (DAS) necessary for maximum yield (DASMFRW, DASMSY, respectively) differed among locations, with the longest period (DASMFRW 206·4 days, DASMSY: 204·5 days) occurring in the northernmost location (Orestiada). Means for DASMFRW and DASMSY at the five locations were estimated at 190·4 and 188·9·days, respectively. Excluding Xanthi and combining the remaining locations, FRWLH and SYLH were negatively correlated with the average temperatures (Tmean, Tmax and Tmin, daily minimum temperature) over the growing season. The opposite was evident for Xanthi where sugar beet was grown under sub-optimal temperatures. The optimum mean Tmax of the five locations was estimated at 25·5 and 25·1 °C for FRWLH and SYLH, respectively. Elongation of the growing season, by means of early sowing, would increase yield by decreasing average temperatures (Tmean, Tmax) over the growing season in locations with the highest recorded temperatures (Larissa, Plati, Serres and Orestiada). In Xanthi, the projected temperature increase, as a result of climate change, is expected to have a positive effect on yields.

A model of the growth, pregnancy and lactation of red deer was developed for incorporation into a whole-farm systems model in order to improve the understanding of venison supply systems. The model estimates the level of metabolic demand for a deer, which depends on the maximum capacity of its tissues to use energy. A function that takes account of satiation signals and rumen capacity is used to convert the metabolic demand into an estimate of the deer's forage intake demand, which can be used as an input into a foraging model. The actual energy intake of the deer is subsequently used to predict live weight (LW), body condition score, foetal growth and gestation length in pregnant hinds, and milk yield in lactating hinds. In order to make these predictions, the model requires inputs that include values for mean daily temperature, mean daily wind speed, day length and season, as well as pasture quality. Values for model parameters were obtained from the literature, rather than by fitting to data, and model predictions were then compared with measurements obtained in independent trials.

In simulations, the model predicted that 152-day-old stags and hinds, weighing, respectively, 44 and 48 kg, would grow to, respectively, 106 and 90 kg when 517 days old, compared with trial results of, respectively, 103 and 84 kg. Predictions for the weight of pregnant hinds, gestation length and calf birth weight compared well with an experiment for hinds on a high plane of nutrition but poorly for hinds on medium and low planes. Weekly predictions of hind LWs for days 132–230 of pregnancy had respective residual means of 0·08, 6·2 and 8·5 kg, and respective residual standard deviations of 1·33, 4·6 and 5·2 kg for the high, medium and low nutritional planes. Predicted gestation length for high, medium and low planes of nutrition were, respectively, 231·5, 238·0 and 242·0 days compared with experimental values of, respectively, 231·3, 234·7 and 239·2 days, while predicted birth weights were, respectively, 8·5, 8·3 and 8·9 kg compared with measured values of, respectively, 8·4, 9·5 and 9·3 kg. Predicted calf growth from birth to 14 weeks agreed well with data (residual mean and standard deviation being 0·04 and 1·15 kg, respectively).

The existing software structure of the whole-farm model dictated that the deer model use the Euler method with a fixed, daily time step. Therefore, the model was constructed using difference (rather than differential) equations and used a traditional, energy-balance method for predicting growth. This empirical approach tacitly imposed a standard body composition and standard metabolic rate for adults, with values corresponding to well-fed deer. This does not cater for variation in body composition and metabolic activity, and in retrospect, caused the model to perform poorly for the medium and low nutritional regimes.

This study examines the effect of sodium (Na) supplementation on the intake and digestibility of Na-deficient feed by cattle, and the potential applicability of faecal analysis to the diagnosis of Na deficiency in the field. Mature cattle fitted with oesophageal fistulae were fed chaffed Setaria sphacelata cv. Nandi hay ad libitum in metabolism cages, with and without a Na supplement (10 g Na daily as NaHCO3). In the first of two experiments the hay contained 0·44 g Na/kg D.M., and in the second, 1·05 g/kg. Prior to an unsupplemented treatment the animals were rapidly depleted of Na by removal of saliva via the fistula; Na status was assessed on the basis of the ratio Na/K in saliva.

When the feed contained 0·44 g Na/kg, Na supplementation increased voluntary intake by 28% (P < 0·01) and digestibility by 12% (P < 0·05). No such responses were obtained in Expt 2, in which the feed contained 1·05 g Na/kg.

Examination of available data suggests that a diagnosis of Na deficiency in cattle is indicated if the faecal Na concentration is below 1 g/kg D.M., and the ratio Na/K in faeces is less than 0·1. Further data are required to confirm these criteria, which should prove useful in the field when samples of saliva, the diagnostic criterion of choice, are not available.

The present study examined variation in sowing date on lentils (Lens culinaris) in a standard lentil–barley (Hordeum vulgare) mixed cropping system in the temperate climate of central Europe to determine the effect on crop yield and weed control. A 2-year (2009/10) field experiment was carried out at the organic research station Kleinhohenheim (KH) and at the conventional research station Oberer Lindenhof (OLI) of the University Hohenheim, southwest Germany. The crop was sown at three dates in the period from March to May. Grain yield was significantly higher at the earliest sowing both for lentils (3·0 t/ha at KH, 2·4 t/ha at OLI) and barley (1·2 t/ha at KH, 2·6 t/ha at OLI). Weed biomass at KH increased significantly with delayed sowing and was independent of lentil genotype, whereas sowing date had no significant effect on overall weed biomass production at OLI. Unlike weed biomass, weed density generally decreased significantly with delayed sowing at OLI. The results indicate that early sowing can increase the yield of lentils, and can be used as an indirect method of weed control in some organic farming systems.

Peach trees initiate flowering and then dense budding when the temperatures in winter are steadily low. When temperatures during the winter are high or when the chilling accumulation needs of the cultivar are not met, it is necessary to apply chemicals that stimulate flowering and budding in a uniform manner. This study aimed to evaluate alternative products for breaking the dormancy of ‘Kampai’ peach trees in a subtropical region. The experiment was conducted with ‘Kampai’ peach trees in the 2018, 2019 and 2020 production with the following treatments: (1) negative control composed only of water (control); (2) positive control composed of hydrogen cyanamide at a dose of 1.5% (commercial product Dormex®) plus 4.5% mineral oil; (3) Erger G® organomineral fertilizer supplemented with calcium nitrate at a dose of 3%; (4) potassium nitrate at a dose of 5%; and (5) copper sulphate at a dose of 0.3%. We evaluated affected budding capacity, flowering, the production cycle, peach production, the quality of peach trees and the enzymatic activities of catalase and guaiacol peroxidase. Hydrogen cyanamide and the organomineral fertilizer Erger G® promoted earlier flowering and an earlier production cycle. On the other hand, hydrogen cyanamide and copper sulphate stimulated flower opening and peach production. The chemicals used decreased catalase activity (24 h after application) and increased guaiacol peroxidase activity (6 h after application). The application of copper sulphate may be an option to break the dormancy of peach trees in the subtropics.

Three adjustment methods using control plots to adjust for soil variation in a modified augmented design (Lin & Poushinsky, 1983) were studied by simulation. The results show that adjustment by design structure (row and column correction factors) is best when soil variation is relatively uniform in one or two directions, while adjustment by regression analysis is best when the variation is multi-directional. Adjustment using the control plot as a fertility index is least satisfactory. A modified augmented design in a replicated experiment is generally inferior to a balanced lattice square design but is competitive when the percentage of environmental variation attributable to soil factors is less than 70% of the total variation.

1. An experiment comparing the growth and productivity of six varieties of lucerne representing a wide diversity of ecological conditions grown in association with S 37 Cocksfoot, S143 Cocksfoot and a commercial cocksfoot/timothy mixture is described and the results discussed.

2. Variety of lucerne had a marked effect on establishment, persistence, recovery from defoliation, early spring growth, yield of total dried produce, proportion of lucerne in that produce and on yield of nitrogen.

3. There was no evidence of differing degrees of compatibility of varieties of lucerne with the three strains of grass used.

1. Trials over 2 years involving 120 Half bred ewes were conducted in outdoor paddocks with controlled feeding. A study was made of the effect of varying the level of feeding during pregnancy on production of ketonaemia and pregnancy toxaemia.

2. Blood ketone levels were low and pregnancy toxaemia absent in ewes gaining weight during the latter part of gestation, but ewes failing to gain weight over the same period were subject to ketonaemia and pregnancy toxaemia. A reduction in the ration of fat ewes for a 3-week period, imposed more than 5 weeks before lambing, had no detrimental effect.

3. A significant correlation was found between loss in weight and highest ketone figure in the highthroughout and the high-checked groups in 1952 and in the high-checked-high group in 1953.

4. High ketonaemia was not always indicative of pregnancy toxaemia, since of the twenty-nine ewes which had, on one or more occasions, over 20 mg. β-hydroxybutyric acid per 100 ml. blood, seven showed signs of pregnancy toxaemia and twentytwo did not.

5. In the cases reported, the time of appearance of the first symptoms of pregnancy toxaemia was around 14 days from the estimated lambing date, and affected ewes tended to lamb before term.

6. On a comparatively low level of nutrition, only one case of pregnancy toxaemia occurred, though some animals had marked ketosis. In well conditioned ewes reduced to a similar level during the critical period, there was a high incidence of pregnancy toxaemia, and in most of these cases a high degree of ketosis.

Seasonal variations in the contents of organic and inorganic constituents of three East African grasses, Bothriochloa insculpta, Chloris gayana and Brachiaria dictyoneura are reported.

Protein content is closely associated with rainfall and the stage of growth of the grasses. Protein content of from 15 to 20% is maintained for a short time only, at the beginning of the rainy season. During the dry season the values fall to 4–5%.

Even in the vegetative phase the fibre contents are relatively high, 23% being the lowest figure recorded.

A common feature of the grasses is a high content of silica, which may amount to more than 10% of the dry matter.

The phosphorus content of the grasses is low, ranging from 0·65% P2O5 in young grass during the rainy season to 0·13% during the dry season.

Mixed rumen bacteria entering the duodenum of a ruminant are a major source of some of the nutrients required by the animal. A number of values for the chemical composition of mixed rumen bacteria have been reported and a few observations made on interrelationships between different components at different times after feeding (Hoogenraad & Hird, 1970; Jouany & Thivend, 1972; Bird, 1973; Smith & McAllan, 1973; Czerkawski, 1975; McAllan & Smith, 1974, 1976). There is also some published information on in vivo variations in the storage carbohydrate in mixed rumen bacteria with different diets (Jouany & Thivend, 1972; McAllan & Smith, 1976) but no information on interrelationships between such variations and changes in other components in the bacteria.

The present paper reports a study of such interrelationships in bacterial samples, containing wide ranges of storage polysaccharide (α-dextran) and crude protein concentrations, obtained from steers given a wide variety of diets.

1. At two centres, Hillsborough and Shinfield, forty-eight pigs in four groups were fattened on rations containing Australian sorghum. The control ration consisted of 30%, wheatfeed, 30% barley meal, 30% maize meal and 10% fish meal. In the three experimental rations either barley meal or maize meal or both were replaced by sorghum.

2. The rations containing 30% of sorghum proved to be equal to the control ration as far as live-weight gain of the pigs and the efficiency with which they utilized food was concerned. When 60% of the ration consisted of sorghum there were indications that both rate of gain and food utilization suffered.

3. Some aspects of carcass quality suffered when either sorghum alone or sorghum plus maize formed 60% of the ration. The quality of the control carcasses, although quite good by present-day standards, would not qualify for first grade when commercial grading is re-introduced.

4. Bacon produced on rations containing up to 60% sorghum had no off-taste or unpleasant flavour.

5. In general, the value of sorghum in the ration of fattening pigs was found to be about equal to that of maize.

Although numerous studies have investigated the individual effects of salinity, irrigation and fertilization on soil microbial communities, relatively less attention has been paid to their combined influences, especially using molecular techniques. Based on the field of orthogonal designed test and deoxyribonucleic acid sequencing technology, the effects of saline water irrigation amount, salinity level of irrigation water and nitrogen (N) fertilizer rate on soil bacterial community structure were investigated. The results showed that the irrigation amount was the most dominant factor in determining the bacterial richness and diversity, followed by the irrigation water salinity and N fertilizer rate. The values of Chao1 estimator, abundance-based coverage estimator and Shannon indices decreased with an increase in irrigation amount while increased and then decreased with an increase in irrigation water salinity and N fertilizer rate. The highest soil bacterial richness and diversity were obtained under the least irrigation amount (25 mm), medium irrigation water salinity (4.75 dS/m) and medium N fertilizer rate (350 kg/ha). However, different bacterial phyla were found to respond distinctively to these three factors: irrigation amount significantly affected the relative abundances of Proteobacteria and Chloroflexi; irrigation water salinity mostly affected the members of Actinobacteria, Gemmatimonadetes and Acidobacteria; and N fertilizer rate mainly influenced the Bacteroidetes' abundance. The results presented here revealed that the assessment of soil microbial processes under combined irrigation and fertilization treatments needed to be more careful as more variable consequences would be established by comparing with the influences based on an individual factor, such as irrigation amount or N fertilizer rate.

In some of the earlier experiments in which Bordeaux Mixture was used as a fungicide, it has happened that neither the part sprayed nor the control has suffered from disease at all; yet it has been recorded that the sprayed part has continued green for a longer period and has produced a larger crop.

The birthcoats of Finnish Landrace lambs showed a wide range of halo-hair grades but all had strongly checked fibre type arrays, which were either Plain or Valley. Transfer to Welsh Mountain dams reduced the effect of prenatal check, giving fewer sickle fibres and increased halo-hair and/or super sickle A percentage. Transfer to Border Leicester tended to have the opposite effect. Fibre diameter measurements made on skin samples indicated an increase in primary fibre diameter in transfers into Welsh dams, but no difference in transfers into the Border Leicester.

All Soay samples had Grade VII halo-hair density and Plateau or Saddle arrays. Transfer of Soay eggs to Finnish Landrace ewes increased the percentage of sickle fibres mainly at the expense of hairy-tip curly-tips. Skin samples from the transferred Soays indicated reduced primary fibre medullation, and evidence of retarded secondary follicle development.

Thus in both breeds the birthcoat changed slightly in the direction of that of the foster-dam. There was, however, no indication that increased prenatal check was associated with increased foetal size. It is therefore concluded that changes in birthcoat as a result of egg transfer are more probably due to direct effects of the maternal environment than to the effect of foetal size as previously postulated.

For many field-grown crops, including sugar beet, there is little information on the seasonal changes in leaf water potential and its components as the soil dries. Therefore, seasonal changes in leaf water, osmotic and turgor potentials of sugar beet were measured in two seasons, in crops that experienced differing degrees of soil moisture stress. In 1983 potentials of crops exposed to early and late droughts were compared with those of irrigated crops, and in 1984 measurements were made in a non-irrigated crop. In the irrigated crop the midday leaf water potential changed little during the season, except in response to fluctuating evaporative demand. In the drought and non-irrigated treatments there was a sharp fall in leaf water potential as soon as the soil water potential decreased. The size of the midday leaf water potential was primarily determined by soil dryness. However, the leaf water potential did not decrease below about — 1·5 MPa in either year. The leaf osmotic potential declined at the same time as the leaf water potential, but the extent to which this happened differed in the two years. Only in the 1984 non-irrigated crop did the osmotic potential continue to decrease as the soil dried, suggesting that osmotic adjustment had taken place in 1984 but not in 1983. Thus higher turgor was maintained in the 1984 crop than in the 1983 drought-affected crops. Some turgors were recorded as apparently negative in 1983.

Since the leaf water potential declined to a minimum of about — 1·5 MPa, the soil water potential minima were also about — 1·5 MPa. However, deeper soil was not dried to this extent, suggesting that the extra resistance for water uptake from deep soil was limiting or the rooting density was too low.

The pattern of recovery of leaf water potential overnight suggested that the rhizosphere resistance to water movement was small, even as the soil dried. However, measurement of stem water potentials in 1984 indicated that a significant resistance to water flow existed within the aerial part of sugar beet plants. This shows that the use of the water potential in leaves as an estimate of that in stems or roots can be misleading.

Integrated crop-livestock systems (ICLS) are currently promoted agricultural production systems that aim to use better resources through production integration and intensification. While this system reduces some risks, it adds complexity and new risks to businesses due to interdependence between the agricultural modules. To deal with these issues, integrated risk management is required to reduce the effects of risks and to take advantage of the opportunities of an ICLS. Generically, enterprise risk management (ERM) meets this need by proposing comprehensive and coherent risk management, instead of managing agricultural module risks individually. However, there is a need to customize the ERM approach to ICLS. Therefore, the current study aims to develop a method to manage risks for ICLS based on ERM, integrating the management of risks and aligning risk management with the strategic objectives. A literature review, a pilot study, interviews with experts, four case studies and 20 practitioners supported the method development and evaluation through three versions. As a result, the method identifies and relates risks through process mapping with a qualitative and quantitative analysis of their impacts, determines risk responses based on willingness to take risks, and helps identify processes to control, communicate and monitor the risks. The method also stimulates the implementation of ICLS in market-oriented farms, providing an approach to increase the chances of ICLS success. The main difference from previous research lies in the integrative management of multiple risks, the alignment of risks with strategy and the consideration that a risk might be considered an opportunity.