Genotype×tillage interaction and the performance of winter bread wheat genotypes in temperate and cold dryland conditions

Growing concerns for food security and the alleviation of hunger necessitate knowledge-based crop management technologies for sustainable crop production. In this study, 13 winter bread wheat genotypes (old, relatively old, modern, and breeding lines) were evaluated under three different tillage systems, i.e., conventional tillage (CT, full tillage with residue removed), reduced tillage (RT, chisel tillage with residue retained) and no-tillage (NT, no-tillage with residue retained on the soil surface) in farmer's fields under rainfed conditions using strip-plot arrangements in a randomized complete block design with three replications in the west of Iran (Kamyaran and Hosseinabad locations) over two cropping seasons (2018–2019 and 2019–2020).The main objectives were to investigate the effects of tillage systems and growing conditions on the agronomic characteristics, grain yield and stability performance of rainfed winter bread wheat genotypes.Significant (P<0.01) genotype×tillage system interaction effects on grain yield and agronomic traits suggested that the genotypes responded differently to the different tillage systems. The number of grains per spike and plant height were positively (P<0.0) associated with grain yield under the NT system, so they may be considered as targeted traits for future wheat breeding. Using statistical models, the modern cultivars (“Sadra” and “Baran”) were identified as high yielding and showed yield stability across the different tillage systems. As per each tillage system, genotype “Sadra” followed by “Zargana-6//Dari 1-7 Sabalan” exhibited higher adaption to CT; while cultivars “Jam” and “Azar2” showed better performance under the RT system; and cultivars “Varan” and “Baran” tended to have better performance expression in the NT condition.The increased grain yields achieved in combination with lower costs and greater profits from conservation agriculture suggest that adapted cultivar and NT systems should be evaluated and promoted more widely to farmers in the west of Iran as an attractive package of crop management technologies.In conclusion, variations in the performance of genotypes and the significant genotype×tillage system interaction effects on grain yield and some agronomic traits assessed in this study suggest that the development and selection of cultivars adapted to the NT system should be considered and included in the strategies and objectives of winter wheat breeding programs for the temperate and cold dryland conditions of Iran.     

Foliar application of micronutrients enhances crop stand,yield and the biofortification essential for human health of different wheat cultivars

Globally about half of the world's population is under micronutrient malnutrition due to poor quality food intake. To overcome this problem, fortification and biofortification techniques are often used. Biofortification is considered a better option than fortification due to the easy control of nutrient deficiencies present in daily food. This field experiment was conducted to evaluate the effects of foliar application of a micronutrient mixture(MNM) consisting of zinc(Zn), iron(Fe), copper(Cu), manganese(Mn) and boron(B) on yield and flour quality of wheat. The results show the effectiveness of foliar feeding for growth and yield parameters, in addition to the enriching of wheat grains with Zn, Cu, Fe, Mn and B. Compared to the control without foliar feeding, foliar application on wheat crop increased tillering ability, spike length, grain yield and the contents of Zn, Cu, Mn, Fe and B by 21, 47, 22, 22 and 25% in wheat flour, respectively. Therefore, foliar feeding of micronutrients could be an effective approach to enrich wheat grains with essential nutrients for correcting malnutrition.     

Response of mustard to seed treatment with pyridioxine and basal and foliar application of nitrogen and phosphorus

In a simple randomised field trial conducted during 1985–86/ 1986–87, the effect of basal nitrogen (45 and 60 kg N/ha) and basal phosphorus (15 and 20 kg P/ha) applications together with the soaking of seeds in 0.025% aqueous pyridoxine hydrochloride solution for 4h and foliar applications of 15 kg N/ha and 5 kg P/ha in two installments at 70 and 90 days after sowing (DAS) was studied on the performance of mustard (Brassica juncea L.). Recommended basal applications of 90 kg N/ha and 30 kg P/ha (BN₉₀P₃₀) was used as the control. The parameters studied included leaf area index (LAI) at 60, 80, and 100 DAS, net assimilation rate at 60–80 and 80–100 day intervals, and pods/plant, seeds/pod, seed yield, oil content, and oil yield at harvest. In general, the pyridoxine treatment proved superior over water soaking. The higher basal fertilizer dose was effective and foliar application of N and P gave higher values as compared to the water foliar application alone. The combination of pyridoxine + BN₆₀P₂₀+ FN₁₅FP₅ significantly enhanced the performance of the crop and enhanced seed yield and oil yield by 15.8 and 13.5%, respectively, over the check BN₉₀P₃₀ treatment.     

Studies on gangrenous mastitis in goats

One hundred and fifty goats were diagnosed as having proven gangrenous mastitis. The disease was categorized into early, intermediate and late stages. Gangrenous mastitis in goats is typified by a sudden onset, dark hyperemia, and edema with progressive discoloration of the distal part of the udder. The disease affected lactating goats but not the dry ones. Coagulase positive Staphylococcus aureus was isolated from 60% of composite and half milk samples obtained from the diseased goats. The histopathological changes mainly comprised proliferation of connective tissue, thrombosis and necrosis involving a group of lobules. Treatment of the early and intermediate stages of the disease was successful through the administration of systemic and intramammary terramycin together with diuretics and topical antiseptic cream. The late stage of the disease was successfully treated only through surgery.     

Infection of calves with Theileria annulata in Tunisia: Economic analysis and evaluation of the potential benefit of vaccination

A field study aiming to estimate the costs of tropical theileriosis was carried out in an endemic region of the North of Tunisia. Three farms were monitored for two successive summer seasons. A total number of 56 calves and 12 sentinel cows were monitored. Calves were ranked into four groups: non infected animals, diseased animals with clinical tropical theileriosis, sub-clinical Theileria annulata infected animals with anaemia and sub-clinical T. annulata infected animals without anaemia. The total costs due to disease and infection were estimated to be 15,115.058 TD (Euro 9388.20). A high proportion of these costs (50.81%) is accounted for by asymptomatic infection. Sub-clinical infections with anaemia showed the highest losses in live weight, while disease cases (prevalence 42.86%) are responsible for 23.64% of the losses with death as the most important element. A cost-benefit analysis of vaccination using a Tunisian attenuated cell line vaccine was also undertaken. Considering that the vaccine would cost 5 TD (Euro 3.10), the cost-benefit ratio of vaccination is 23.7. Sensitivity analysis of the vaccination costs shows that the indifference decision point is around 118 TD (Euro 73.29).     

Differences in partial resistance of barley to powdery mildew (Erysiphe graminis DC F.SP. hordei Marchal) after chemomutagenesis. II. Reaction of mutants to pathotypes

Summary Seedlings of 45 barley mutants with partial resistance in the field and their parental cultivars Asse, Bomi, and Vada were exposed to six local and two foreign races of powdery mildew, in climatically controlled cabinets. Infectability, pustule size, infection grade, and infection type were estimated. No mutant did demonstrate strong race-specific reactions although some race-specific interactions of moderate grade could be detected. The results of infection of mutants with single races confirmed the quantitative character of their change in resistance determined in the earlier field assessments. The 20 investigated mutants with increased resistance expressed a lower level of disease with each of the used races. Out of the 10 mutants with higher susceptibility in the field, 4 mutants again exhibited higher degrees of infection over all the different races, while the remaining 6 mutants were not distinguishable from the original cultivar under the given growing conditions. Out of the tested 14 developmentally resistant mutants, only the 5 genotypes with different seedling reaction could be analyzed for race-specificity in this study. In all the above cases as the result of one gene mutation, quantitative shifts in level of infection were recorded over all the 8 races.Qualitative estimates of infection type were supported by data on the frequency of chlorotic or necrotic lesions and green islands on the infected leaves. But quantitative methods of assessment, e.g. infection frequency and pustule size, were more effective in studying partial resistance of the mutants. Infection grade, estimated visually 14 days after inoculation, was in agreement with the quantitative parameters accurately measured 7 days after inoculation. Therefore, its careful use can be recommended to speed the screening by narrowing down the materials. Differences in virulence level of the races were observed and their influence on race-specificity studies was discussed.     

Subconjunctival Dirofilaria repens infection in a dog resident in the UK

Dirofilaria repens infection was diagnosed in a 5‐year‐old female German shepherd crossbreed, originally from Romania but brought into the UK in February 2014. The dog presented with conjunctivitis in March 2014 and then again 2 months later with additional ocular and nasal mucopurulent discharge. Bacterial cultures from the nasolacrimal duct were negative for bacterial growth. The case was referred in August 2014 for ophthalmic examination, which revealed abnormalities in both eyes, especially the left. They included mild palpebral conjunctival hyperaemia and marked follicular conjunctivitis, as well as a dorsonasal bulbar conjunctival mass. Serum biochemistry was unremarkable and a conjunctival biopsy taken from the dorsonasal bulbar conjunctival mass revealed eosinophilic/lymphoplasmacytic conjunctivitis. At re‐examination, nematodes were found in the area of the previous biopsy site and in the ventral palpebral conjunctival fornix. Polymerase chain reaction and sequencing confirmed these to be D. repens. Treatment with 10% imidacloprid and 2·5% moxidectin (Advocate Spot‐On) was successful, and clinical signs resolved over a 6‐week period. This case report indicates that D. repens infection should be considered as a possible aetiological cause of ocular lesions in dogs in the UK, especially those with a history of foreign travel. Implications for establishment and spread of D. repens in the UK are discussed.     

Predictors of beef calf temperament at weaning and its impact on temperament at breeding and reproductive performance

Two experiments were conducted to determine (i) factors influencing calf temperament at weaning, (ii) association between heifer–calf temperament at weaning and temperament at breeding and (iii) effect of heifer–calf temperament on pregnancy rate per artificial insemination (P/AI). In experiment 1, beef cows and their calves (n = 285) from three farms were used. Sire docility estimated progeny difference (EPD) score, birth type (normal or assisted), calf gender, calf behaviour (during 1st 4 weeks) and calf health status (until weaning) were recorded. Cows and calves were assigned a temperament score (0—calm; 1—excitable), and all cows were given a body condition score (BCS, 1–9; 1—emaciated; 9—obese) at weaning. Calf's illness (p < .05), low sire docility EPD score (p < .05), altered gait (p < .05), altered resting behaviour (p < .01), reduced/no play behaviour (p < .05) and cow excitable temperament (p < .001) increased calf excitable temperament at weaning. In experiment 2, replacement heifer–calves (n = 758) from 12 farms were assigned a temperament score at weaning and later at breeding. Blood from 40 calves at weaning and 31 heifers at initiation of synchronization (same animals) was collected by coccygeal venipuncture for determination of circulating cortisol and substance P concentrations. Heifers were assigned a BCS and reproductive tract score (RTS, 1–5; 1—immature, acyclic; 5—mature, cyclic), synchronized for fixed time AI, observed for oestrus and were artificially inseminated. Cortisol concentrations were increased in excitable heifer–calves compared to calm heifer–calves at weaning (p < .05), and substance P was increased in excitable compared to calm females both at weaning and breeding (p < .05). Low sire EPD docility score (p < .01), heifer–calf excitable temperament at weaning increased excitable temperament at breeding (p < .01). Controlling for BCS categories (p < .01), oestrous expression (p < .0001) and temperament at breeding by oestrous expression (p < .05), the calf's excitable temperament at weaning (p < .001) reduced P/AI (Calm, 62.7 (244/389) vs. Excitable, 53.4% (197/369); p < .01). In conclusion, selection of docile cows and sires with greater docility EPD score should be given consideration to reduce calf excitement. Temperament in beef female can be detected earlier in their life and could be used as a tool in the selection process and to improve their performances.     

Desaturation of myristoyl-CoA to myristoleoyl-CoA by hen liver microsomal delta(9)-desaturase

The desaturation of myristoyl-CoA to myristoleoyl-CoA was measured in microsomal preparations of hen liver. The desaturation was maximal at pH 7.4. The enzymatic activity was linear with time up to 10 min and proportional to microsomal protein concentrations. The initial velocity was linear with substrate concentrations between 13 and up to 200 microM. A decrease in desaturation activity was observed at substrate concentrations greater than 266 microM. There was an absolute requirement for reduced pyridine nucleotide (NADH), while a maximum activity was observed at a myristoyl-CoA:NADH mole ratio of 1. Competitive inhibition studies of myristoyl-CoA desaturation suggest that the inhibitors, stearyl and oleyl-CoA, were more effective than palmitoyl-CoA. Free CoA did not inhibit the delta(9)-desaturase system. The desaturation of myristoyl-CoA was stimulated by bovine serum albumin and reduced by cytoplasmic proteins. The effect of cytoplasmic proteins on the enzymatic reaction was completely abolished by trypsin digestion and boiling for 30 min. On the basis of these data, it was concluded that 9,10-desaturation of acyl-CoA derivatives containing 14-18 carbon fatty acyl chains is catalyzed by the same enzyme.     

Degradation mechanism of small molecule-based organic light-emitting devices

Studies on the long-term degradation of organic light-emitting devices (OLEDs) based on tris(8-hydroxyquinoline) aluminum (AlQ3), the most widely used electroluminescent molecule, reveal that injection of holes in AlQ3 is the main cause of device degradation. The transport of holes into AlQ3 caused a decrease in its fluorescence quantum efficiency, thus showing that cationic AlQ3 species are unstable and that their degradation products are fluorescence quenchers. These findings explain the success of different approaches to stabilizing OLEDs, such as doping of the hole transport layer, introducing a buffer layer at the hole-injecting contact, and using mixed emitting layers of hole and electron transporting molecules.