Turkey is one of the most important durum wheat (T. turgidum L. var. durum Desf.) producers in West Asia and North Africa (WANA). There appears to have been a lack of progress in wheat yields in WANA over recent decades. Most of the modern cultivars grown in WANA are related to crosses produced by the International Maize and Wheat Improvement Center (CIMMYT). During 1999 and 2000, a chronological set of 11 cultivars related to CIMMYT crosses was evaluated using two irrigation regimes near Şanlıurfa, Turkey.

Average yields ranged from 386 g/m2 (local cultivar, Karakılçık-33) to 614 g/m2 (Ege-88). When wheat cultivars were grown with irrigation until physiological maturity, cessation of irrigation near anthesis reduced average grain yields of all cultivars by 6·2–25·7%. Since the introduction of the first generation of CIMMYT cultivars in 1975, CIMMYT grain yields have increased by about 0·60% per year compared with that of Karakılçık-33. This rate increased up to 1·08% per year until 1988. No further progress in yield was measured for varieties released in the 1990s. The average rate was 0·76% per year. After the introduction of the CIMMYT cultivars, yield changes fitted better in a quadratic function. Compared with Karakılçık-33, the yield increases of CIMMYT cultivars have resulted from an increase in harvest index associated with reduced height and the development of more and heavier grains. Grain quality traits decreased with the introduction of the first CIMMYT cultivar but recovered slightly thereafter with no clear trend. The results are discussed with consideration of breeding priorities and specific WANA conditions.

In tropical and subtropical areas many cattle suffer from heat stress for more than half of each year. Added to the environmental heat stress is the heat production associated with lactation (Berman et al. 1985) and the resultant increased storage of heat (Araki et al. 1984). While the net effect of lactation on body temperature has been evaluated in dairy cattle (Collier et al. 1982) its effect on beef breeds in tropical and subtropical areas has not been defined. This is now possible with improved telemetry equipment, which allows body temperatures of free-ranging cattle to be monitored up to distance of 400 m.

Results are described of an experiment involving various pearl millet–cow pea or green gram planting and interplanting systems under four levels of nitrogen and two levels of phosphorus. Planting of pearl millet in paired rows of 30 and 70 cm gave as much yield as normal planting in uniform rows of 50 cm. The productivity per unit area was increased considerably when pearl millet was interplanted with one row of cow pea or green gram. Cow pea gave higher yield than green gram. Nitrogen fertilizer increased pearl millet as well as intercrops yield significantly. Pearl millet responded up to 60 kg N/ha and intercrops up to 30 kg N/ha. Phosphorus fertilizer did not produce marked improvement in either growth or yield of pearl millet. Application of 40 kg P2O5/ha increased grain yield of intercrops significantly

Although the first or second clonal cuttings of heat-treated sugar cane were widely used for seed, differences were not detected among crop years or locations in the incidence of ratoon stunting disease. Sugar-cane mosaic virus (SCMV) disease was widespread in all areas surveyed; however, the plant cane crop had a lower incidence of SCMV than the first or the second ratoon crop. The estimated cane yield was increased approximately 19·4 t/ha by heat treatment during the 2-year survey period.

The management system used to control the sugar-cane borer (SCB), Diatraea saccharalis (F.), was effective regardless of the crop year or area surveyed. Season-long SCB control was achieved by the use of two (1981) or three (1982) properly timed applications of insecticide and the use of a SCB moderately resistant variety resulting in an average of 6–9% bored sugar-cane internodes.

Poor weed management, particularly with johnsongrass (Sorghum halepense(L.) Pers.), accounted for much of the reduction in cane yield (P < 0·01); the estimated yields of the second ratoon crop were substantially altered, particularly those of farms surveyed in the Bayou Lafourche area.

The present paper demonstrates the development of interspecific hybrids between Manihot esculenta Crantz ssp. esculenta (Mee) and M. esculenta Crantz ssp. flabellifolia (Mef) and paternity analysis using microsatellite markers [simple sequence repeat (SSR)]. Three Mef accessions (FLA005, FLA025V and FLA029V) were used for crosses with varieties of Mee: Saracura, Aipim Bravo, COL 1725, Aipim Rosa, Abóbora, Paraná and PER334. The paternity of the interspecific hybrids was investigated using 24 SSRs. The observed heterozygosity (Ho), polymorphic information content (PIC), probability of identity (PI) and paternity exclusion (PE) were evaluated. The rate of breeding success varied from 17 to 92%, and an average of two pollinations were required for each generated hybrid plant. The Ho value ranged from 0·11 to 0·92, and the PIC value ranged from 0·12 to 0·59. The uneven distribution of allele frequencies was accompanied by a high PI average (0·56). However, the combined PE for 21 loci was 0·99, which allows for the determination of the paternity of the hybrids with good discriminatory power. Of the 74 hybrids evaluated, 0·82 had their paternity confirmed using microsatellite markers. Discriminant analysis of principal components (DAPC) indicated the presence of eight clusters, of which, one was composed of only Mef varieties and the supposed hybrid Fla52Sar-H7, which was a product of apomixis. The parent Mee and hybrids were allocated in the other seven clusters. The data obtained demonstrate that SSR markers can be routinely used in breeding programmes to verify the paternity of interspecific crosses of cassava.

Pig manure management systems in Taiwan differ from the model representing the Asian region developed by the Intergovernmental Panel on Climate Change (IPCC). The current study was undertaken to update greenhouse gas (GHG) emission factors of anaerobically treated piggery waste water by operating the conventional three-step piggery waste-water treatment system from selected pig farms located in northern, central and southern Taiwan. Biogas mass flow meters were installed to the outlet of anaerobic basins prior to the biogas pressure stabilizers for direct and reliable biogas measurement. The analytic results showed that average GHG emissions were 0.088, 0.128 and 0.066 m3/head/day in the northern, central and southern pig farms, respectively. Thus, the average emission levels of methane and nitrous oxide were 14.38 and 0.055 kg/head/year, respectively, from anaerobic digestion of piggery waste water for the three pig farms. The average removal efficiency of chemical oxygen demand, biochemical oxygen demand and suspended solids by anaerobic digestion process from the three pig farms was about 77, 93 and 70%, respectively.

The loss of potassium through the cutaneous route was measured in three Chokla rams by balance trial and by washing the animals (ambient temperature 28–33 °C, 28–30 mmHg vapour pressure). The excretion of potassium through urine and faeces was 46·7 and 19·4% of the intake, respectively. The excretion through skin recorded by washing the animals was 29·1% against 33·7% potassium available for excretion through the thermoregulatory route. About 2·56 g potassium was thus excreted through the cutaneous route per day. There was a net retention of 9·8 g sodium/ram/day.

The chemical composition of eight samples of fresh material and ninety-one samples of different kinds of silage has been determined. The crude protein varied from about 10 to 20 %. Judging by the appearance and edibility of the material, the silage samples made by the A.I.V. process were almost uniformly good. Their pH values were mainly between 3·5 and 3·8, and they contained less volatile acids and volatile bases than the other silages, and showed the highest proportions of lactic to acetic acid and amino-acids to volatile bases. The results as a whole show a fairly close agreement between pH., volatile acids and volatile bases, but attention is directed to the possibility of anomalous figures when, through secondary changes, the pH value has risen to about 6 or 7.

Two calves (Zebu × Australian Illawara Shorthorn and Shorthorn) of about 7–8 months of age were exposed to controlled atmospheric conditions. Cutaneous evaporation from the belly area of these calves was measured by the capsule method. Records of the temperature of the skin under test and that of the air passed over the skin was also maintained.

The amount of water passing through the cattle skin was proportional to the difference between the saturated water-vapour pressure at skin temperature and the water-vapour pressure in the air. Tests were made for the water-vapour pressure difference varying from 9 to 25 mm. Hg.

Pigs were fed either at 3, 6 or 12 hourly intervals to a scale based on live weight from 21 kg to slaughter at 79 kg live weight. There was no effect of treatment on daily gain, feed efficiency or killing out percentage. Backfat thickness at C and K was increased by four times-a-day feeding compared with feeding twice or eight times/day, but this increase in fatness was not confirmed by sample joint dissection.

The North China Plain suffers excessive application of nitrogen (N) and soil degradation. Recently, biochar has been promoted as an agricultural soil amendment to ameliorate soil quality, increase crop yield and mitigate greenhouse gas emissions. However, most proofs on the positive effects of biochar addition have been based on small plots or short-term field studies located in tropical or subtropical regions with defective soils. A long-term field experiment was designed with five N levels and two biochar rates to observe the changes in crop (winter wheat and summer maize) growth and soil chemical quality. Notably, crop yield was strongly dependent upon N application, with both wheat and maize yields increasing with N application. Biochar addition increased crop yield but not significantly, although the increase in grain yield was 0.96 t/ha in a rotation. Correlation analysis revealed that the optimal root-layer soil mineral N (Nmin) for crop production was around N120, especially with biochar addition. The effect of fertilization on soil chemical quality was mainly reflected in the increase in soil organic carbon (SOC), and the highest value was obtained at N60 whether or not biochar was applied. Overall, biochar addition did not appear to promote wheat and maize growth or increase the yield on calcareous alluvial soils in temperate regions, but significantly enhanced SOC content, especially at N60, which may play an important role in sustainable agricultural production.

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.

A survey of the fertilizer value of certain highly concentrated N and NP materials, particularly salts of urea and of guanidine, which might be used as fertilizers, has been made. The evidence in the literature indicates that whilst guanidine carbonate and nitrate, especially the latter, may under certain conditions be toxic to the growth of certainc plants, under other conditions these guanidine salts have considerable fertilizer value which is, however, less than that of ammonium sulphate. Urea nitrate appears to have about the same value as guanidine nitrate. No reference to experiments with guanidine or urea phosphates could be found. Pot culture experiments were conducted with barley and mustard in acid and neutral soils to study the effects of ammonium, urea and guanidine salts, including their nitrates and phosphates, and of two extremely concentrated materials, phospham (PN2H) and phosphorus nitride (P3N5). The rate of nitrification of ammonium, urea and guanidine nitrogen were also studied in the laboratory.

1. During the winter of 1956-57, three levels of indoor feeding, high, mid, and low, were imposed on groups of North and South Country Cheviot ewe hoggs (sheep between 6 months and 1½ years) born 1956. During the winter of 1957-58, only two levels, high and mid, were fed indoors to groups of hoggs born 1957, with the low level being represented by hill wintering. After 12 months of age in each year, all were grazed together on the same hill pasture.

Thirty-two weaned Kenana bull calves were adequately fed to maximize growth and serially slaughtered at predetermined live weights of approximately 100, 200, 300 and 400 kg. Eight animals were slaughtered at each slaughter point and slaughter data collected. Dressing-out percentage increased with the increase in slaughter weight but the increase was more marked between the first and the second slaughter points than between subsequent slaughter points. Kenana cattle compare favourably with Hereford, Hereford × Friesian, Friesian and Shorthorn × Ayrshire steers in dressing-out percentage; and are, apparently, superior to Jersey steers in that trait.

The model, y = axb, in the logarithmic form, was used to describe patterns of proportional weight increase of body components throughout the experimental period and in three arbitrary phases. The patterns of development which were demonstrated by some body components throughout the test period were not necessarily re-exhibited, in all stages, when development was considered in phases. These body components changed their patterns of proportional increase in weight as development proceeded.

Grain production potential (GrPP) is the maximum production in 1 year that can be achieved by land use under the limitations of climate conditions and in the absence of pests and diseases and other factors. Regional GrPP can change over time and there is an urgent need to identify the main factors affecting regional differences in such changes. Therefore, changes in GrPP were studied for six geographical units in Shaanxi Province, with summer maize and winter wheat as the main grain crops. Changes of GrPP during 2000–2015 were simulated by the global aro-ecological zone model. Analysis of modelled GrPP driven by observed changes in climate and land use suggest that over this period GrPP increased to the north but declined to the south of the Qinling Mountains. This is driven mainly by past changes in climate, with modelled GrPP more sensitive to changes in precipitation than temperature in all geographical units except one. Climate change was the main factor affecting GrPP in all geographical units except one; however, model prediction suggests that land use changes had a clear yield-reducing effect in three of the units. It is the conversion from cultivated land to construction land, grassland and woodland that led to the greatest declines in GrPP in these three geographical units. In order to ensure the stable development of regional agriculture and food security, Shaanxi Province should focus on tapping GrPP north of the Qinling Mountains and increasing the conversion rate of GrPP to actual production.

Pearl millet (Pennisetum glaucum (L.) R.) is an important crop for rainfed production systems and can play a significant role as a feed source for ruminants owing to its high yield and drought tolerance. It is well-established that the maturity stage can influence the chemical composition as well as the nutritional value of crops traditionally used for silage production, although quantitative evidence that this occurs with pearl millet under rainfed conditions is lacking. The current research assessed the agronomic characteristics, ensilability, intake and digestibility of a Brazilian pearl millet cultivar (IPA BULK1-BF) harvested at four different growth stages. Forage was harvested at 35, 50, 65 and 80 days after sowing and ensiled under laboratory and farm conditions. Apparent digestibility of the silages was determined using 24 male lambs. The results showed that dry matter (DM) and panicle and stem proportions increased with the advancement maturity. The silage evaluations showed that DM, total and non-fibrous carbohydrates and lignin concentrations increased, while crude protein, ADF and in vitro DM digestibility decreased with the increase in plant maturity. Additionally, the fermentation characteristics were improved with the increasing maturity. The digestion study showed that intake of DM and N as well as digestibility of DM and fibre fractions decreased, while lignin intake increased. The results obtained for the production of dry and digestible DM, the ratio of plant fractions and fermentation parameters indicate the possibility of harvesting pearl millet forage after 50 days after sowing for silage production in the Brazilian semi-arid region.

Exposure of sheep to a long-day photoperiod during late pregnancy results in greatly increased plasma prolactin concentrations in both the ewe and her fetuses compared to values in animals experiencing short days. To investigate whether the endocrine changes resulting from provision of additional lighting might also influence the pre- and postnatal growth of lambs or udder development in winter-housed ewes, two experiments were carried out. In the first, a group of housed Mule ewes, lambing in early January 1989, were given additional lighting to provide a long-day photoperiod [16 h light: 8 h dark] from 6 weeks before delivery until 6 weeks after lambing. In the second experiment, 50 housed Mule ewes were given additional light for 7 weeks before delivery at the end of March 1990. In both experiments, comparable groups of housed Mule ewes experiencing only the natural shortday winter photoperiod served as controls.

In both experiments, provision of the long-day photoperiod resulted, within 3 weeks, in highly significant increases in plasma prolactin concentrations in the ewes. Plasma prolactin concentrations in the lambs from ewes experiencing the long-day photoperiod were also increased at birth (8-fold) and throughout the suckling period (3–5-fold) compared to values in short-day control lambs.

Despite these large differences in plasma prolactin concentrations, there was no significant effect of photoperiod on the birth weight of the lambs in either experiment. There was also no effect of photoperiod on the postnatal growth of lambs in Experiment 1.

Provision of a long-day photoperiod resulted in some increase in the rate of growth of linear measurements of udder size in ewes during both experiments, but only resulted in a significant increase in estimated udder size at delivery in ewes with twins or larger numbers of fetuses in the first experiment. In both experiments the effect of a long-day photoperiod on udder size was similar to or less than the effect of one additional fetus.

The results do not suggest that prenatal photoperiodic experience results in any major alteration in somatic development in lambs at birth or during early postnatal life. They do, however, give some support to other observations that ambient photoperiod may influence pre-partum udder development in the ewe.

A feeding trial involving growing piglets was undertaken to establish whether feed supplemented with whey protein concentrate (WPC), exhibiting antioxidant properties, had any effects on welfare and meat quality. For that purpose, 48 weaned piglets (20-days-old) were assigned to two experimental groups receiving standard or experimental diet for 30 days. Blood and tissue collection were performed at various time-points. The following oxidative stress markers were assessed: reduced glutathione (GSH), catalase activity, total antioxidant capacity (TAC), thiobarbituric acid reactive substances (TBARS), protein carbonyls (CARB) and hydrogen peroxide (H2O2) decomposition activity. The effects on bacterial growth and the fatty acid profile of meat were also assessed. Results showed that piglets fed with the WPC-supplemented diet had significantly increased antioxidant mechanisms in almost all tissues tested, as indicated by increases in GSH, H2O2 decomposition activity and TAC compared with the control group. Piglets fed with the experimental diet exhibited decreased oxidative stress-induced damage to lipids and proteins, as shown by decreases in TBARS and CARB in the WPC group compared with the control group. In addition, the experimental diet enhanced growth of facultative probiotic bacteria and lactic acid bacteria and inhibited growth of pathogen populations. In addition, WPC inclusion in piglets' diet increased n-3 fatty acids significantly and decreased n-6/n-3 ratio significantly compared with the control group. The current study showed that WPC inclusion in the diet had a significant effect on welfare and meat quality of growing piglets.

In each of two experiments two potato varieties were grown at a range of plant densities in order to provide mature tubers of different sizes for the study of the relationshipsbetween tuber size and tuber concentration of nitrogen (N), phosphorus (P) and potassium (K). As tuber size increased, the concentrations of tuber nutrients (g/100 g dry matter) declined to a minimum value and then tended to increase with a further increase in tuber size. This suggests that when tuber samples are taken for the determination of tuber nutrient concentration on a dry-weight basis the sampling procedure should ensure that results do not vary because of differences in the tuber size distribution.