Incidence and within field dispersion pattern of pod borer,Helicoverpa armigera (Lepidoptera: Noctuidae) in chickpea in Ethiopia

Podborer is a major pest of chickpea in Ethiopia. Field surveys were conducted in 2013/2014 and 2014/2015 in central and northwestern Ethiopia to assess the prevalence and within field distribution of the pest. Although podborer was prevalent throughout the surveyed areas, there was a significant difference in larval density (0.10–3.75 larvae per m²) among zones and districts within zones. This variation was attributed to cropping history, cropping patterns, chickpea-crop adjacency, and weather (rainfall and temperature) conditions before and during the season as well as control measures applied. The optimum sample size required for precision ranged from 98, when podborer density was 10/m², to 1045, when podborer density was ≤1/m². Within field distribution of the larvae fitted a negative binomial distribution indicating that the larvae had a clumped/aggregated dispersion pattern. These results will enable chickpea stakeholders to develop and apply appropriate integrated crop management techniques for the control of podborer.     

Detection of naturally aerosolized <Emphasis Type="Italic">Mycoplasma hyopneumoniae</Emphasis> from the air of selected swine farms

We aimed to detect Mycoplasma hyopneumoniae from the air of selected farms through air filtration-based air sampling using polymerase chain reaction (PCR). Air samples were collected at different locations inside and outside of pig farm rooms on polyethersulfone membrane (0.22 μm), and the presence of M. hyopneumoniae DNA was analyzed by PCR. Furthermore, nasal swab and blood samples were collected from 336 pigs in the same air sampled rooms and were analyzed by PCR and IDEXX ELISA, respectively. The suitability of the air sampling method was validated with analysis of an artificially induced aerosolized avirulent M. hyopneumoniae in an enclosed box showing PCR-positive results. M. hyopneumoniae was detected from air sample of pig farm rooms using PCR. Although the probability of an airborne M. hyopneumoniae causing an infection is not yet confirmed, air sampling PCR results could serve as a tool to assess the spread of M. hyopneumoniae by bioaerosols and the infection dynamics in a herd and between herds.     

Current status of wilt/root rot diseases in major chickpea growing areas of Ethiopia

Wilt/root rot diseases are a major chickpea production constraint in Ethiopia causing yield losses by reducing the number of plants. To determine the current status of disease incidence and distribution, surveys were conducted in the 2013/2014 and 2014/2015 cropping seasons in major chickpea growing zones of Ethiopia. Despite recent efforts in dissemination of improved varieties, low to high incidence of 0.0–83.4, 0.0–27.6, 1.3–19.8 and 0.0–16.3% and 1.0–81.9, 0.0–25.5, 3.0–13.9 and 1.0–21.5% in East Gojjam, Southwest Shewa, North Shewa and West Shewa in 2013/2014 and 2014/2015, respectively. Therefore, integrated pest management strategies should be developed and availed to farmers.     

Genetic diversity and demographic history of the Old World Bollworm,Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), in Ethiopia inferred from mitochondrial gene sequences

The Old World bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), is a globally distributed agricultural and horticultural insect pest. Despite the economic importance of this insect in Ethiopia, its genetic diversity and demographic history are poorly understood. We examined the nucleotide variation of the mitochondrial cytochrome c oxidase subunit I (COI) gene fragment of 74 H. armigera individuals from six collection sites in Ethiopia. We recorded 15 COI haplotypes in H. armigera, ten globally shared and five exclusive to Ethiopia (HaET15, HaET14, HaET10, HaET7, and HaET4). Haplotype HaET1 was the most widely geographically distributed and frequent (71.62%). Analysis of molecular variance (AMOVA) revealed a high and significant level of variation within H. armigera populations (θ_ST  = −0.0135). Negative values of the neutrality test and nonsignificant index of mismatch distribution supported the demographic expansion of H. armigera populations in Ethiopia; furthermore, this was also supported by the nonsignificant values of the sum of squared deviations (SSD) and raggedness index (r). The high genetic variation and population expansion of H. armigera have immense implications for devising locally adapted management strategies in area‐wide integrated pest management IPM programs. However, a comprehensive study of H. armigera genetic diversity and population structure using various molecular markers is needed for future confirmation.     

Effects of dietary supplementation of Lactobacillus pentosus PL11 on the growth performance,immune and antioxidant systems of Japanese eel Anguilla japonica challenged with Edwardsiella tarda

The aim of this study was to determine the efficacy of dietary administration of Lactobacillus pentosus PL11 on growth performance and the immune and antioxidant systems in Japanese eel Anguilla japonica challenged with Edwardsiella tarda. A total of 75 Japanese eels (24.63 ± 0.83 g) were grouped into 5 treatment diets which were a control diet (C) without E. tarda and 4 treatment diets with E. tarda challenge, including C for E. tarda challenge (NC), C plus L. pentosus PL11 supplemented diet (10⁸ cfu g^?1) (T-PL11), C plus L. pentosus KCCM 40997 supplemented diet (10⁸ cfu g^?1) (T-Lp) and C plus Weissella hellenica DS-12 supplemented diet (10⁸ cfu g^?1) (T-Wh) for 5 weeks (4 week before and 1 week after challenge). The results showed enhanced growth performance in fish fed the diet containing L. pentosus PL11 compared to others. The growth performance parameters including specific growth rate (SGR) and weight gain (WG), feed intake (FI), feed conversion ratio (FCR) and survival were significantly (P < 0.05) higher in fish maintained on L. pentosus PL11 supplemented diet compared to C and NC. T-PL11 group also shows a significant increase in the levels of plasma immunoglobulin M, CAT and SOD activities compared to NC. Hematological parameters and mieloperoxidase were significantly better in fish fed the L. pentosus PL11 supplemented diet than in the control. L. pentosus PL11 supplementation recover the reduced expression of SOD, CAT and heat shock protein 70 genes in liver and intestine in pathogen challenged fishes. In conclusion the result of the current study demonstrated L. pentosus PL11 potential as an alternative to antibiotic supplementation to improve the growth and health performance of Japanese eel (A. japonica).     

Prevalence of Trachoma at Sub-District Level in Ethiopia: Determining When to Stop Mass Azithromycin Distribution

Background

To eliminate blinding trachoma, the World Health Organization emphasizes implementing the SAFE strategy, which includes annual mass drug administration (MDA) with azithromycin to the whole population of endemic districts. Prevalence surveys to assess impact at the district level are recommended after at least 3 years of intervention. The decision to stop MDA is based on a prevalence of trachomatous inflammation follicular (TF) among children aged 1–9 years below 5% at the sub-district level, as determined by an additional round of surveys limited within districts where TF prevalence is below 10%. We conducted impact surveys powered to estimate prevalence simultaneously at the sub-district and district in two zones of Amhara, Ethiopia to determine whether MDA could be stopped.

Methodology

Seventy-two separate population-based, sub-district surveys were conducted in 25 districts. In each survey all residents from 10 randomly selected clusters were screened for clinical signs of trachoma. Data were weighted according to selection probabilities and adjusted for correlation due to clustering.

Principal Findings

Overall, 89,735 residents were registered from 21,327 households of whom 72,452 people (80.7%) were examined. The prevalence of TF in children aged 1–9 years was below 5% in six sub-districts and two districts. Sub-district level prevalence of TF in children aged 1–9 years ranged from 0.9–76.9% and district-level from 0.9–67.0%. In only one district was the prevalence of trichiasis below 0.1%.

Conclusions/Significance

The experience from these zones in Ethiopia demonstrates that impact assessments designed to give a prevalence estimate of TF at sub-district level are possible, although the scale of the work was challenging. Given the assessed district-level prevalence of TF, sub-district-level surveys would have been warranted in only five districts. Interpretation was not as simple as stopping MDA in sub-districts below 5% given programmatic challenges of exempting sub-districts from a highly regarded program and the proximity of hyper-endemic sub-districts.     

Phytotoxicity of tracer 120SC on greenhouse-grown rose (Rosa sp.) flowers

Tracer 120SC is effective against several insect pests of different crops, but it may be phytotoxic. The objective of this study was to quantify the phytotoxic effect of Tracer 120SC on rose. Phtotoxicity of Tracer 120SC was tested at three rates. A single application of Tracer 120SC caused acute phytotoxic damage to leaves, shoots and flower stalks at all tested rates. Two to three days after spraying symptoms were observed on 32.2 to 52.0% of sprayed shoots, with severity of 26 to 38%. Damage on individual shoots without flower buds varied between 21.1 and 37.6%. Similarly, the proportion of damaged leaves per flower stalk ranged from 57.8 to 62.3%. Flower damage was highest of any tissue, with 79.5 to 90% of tissue exhibiting phytotoxic symptoms. Taken together all flower stalks exhibited damage and were not marketable.