Quantitative Trait Loci for Resistance to Potato Dry Rot Caused by Fusarium sambucinum

Tuber dry rot is an important disease of potato caused by soil and seed-borne pathogens of the Fusarium genus leading to losses that may reach 60% of the yield. The goal of this work was to study the inheritance of the dry rot resistance in two diploid potato hybrid populations (11-36 and 12-3) with complex pedigrees, including several wild Solanum spp. We used an aggressive isolate of F. sambucinum for phenotyping both progenies, parents, and standard potato cultivars in laboratory tuber tests, in three subsequent years. The QTL for dry rot resistance were mapped by interval mapping on existing genetic maps of both mapping populations. The most important and reproducible QTL for this trait was mapped on chromosome I and additional year- and population-specific QTL were mapped on chromosomes II, VII, IX, XI, and XII, confirming polygenic control of this resistance. This is the first study mapping the loci affecting tuber dry rot resistance in potato genome that can contribute to better understanding of potato-F. sambucinum interaction and to more efficient breeding of resistant potato cultivars.

Efficacy of Different Plant Extracts on Fusarium Wilt caused by Fusarium oxysporum in Chillies under Field Condition

Chilli (Capsicum annum L.) is vegetable crop belongs to family Solanaceae. It is an important source of vitamin A and C. In developing countries most of chilli diseases are due to fungal attack and cause severe losses in yield. Fusarium wilt of chilli which is caused by Fusarium oxysporium f. sp. capsici is an important disease of chilli which causes heavy yield losses in Pakistan. Present research was planned to evaluate effect of different concentrations of plant based phyto-extracts against Fusarium wilt on chilli pathogen under natural field condition. In research trails the leave extract of Euclayptus globulus, Cassia fistula, Moringa oleifera, Vachellia nilotica and Azadirachta indica were evaluated in the management of fusarium wilt. These trails were planned under Randomized Complete Block Design (RCBD). Three concentrations of above mentioned leaf extracts were used 20%, 30% and 40%. At 40% Eucalyptus, Moringa and Azadiracta gave best results with maximum reduction in Fusarium wilt. While all other extracts results were also satisfactory. So we can use these botanicals as a control for this disease in chilli. Keywords: Capsicum annum, Fusarium wilt, Fusarium oxysporium, Phyto-extracts.

Virulence Structure of the Wheat Powdery Mildew Population in Serbia

Powdery mildew is a common, economically important disease in the wheat growing area of Serbia. A large-scale virulence survey of its causal agent Blumeria graminis f. sp. tritici population was performed in the period 1995–2013. A total of 1013 isolates were recovered from the collected chasmothecial samples. Among them, 862 unique pathotypes were identified using a differential set of 20 wheat lines with known powdery mildew (Pm) resistant genes. The pathogen was highly diverse. Number of virulence genes (virulence complexity) per isolate was large, supporting a constant need to extend the differential set of wheat with newly identified Pm genes. Virulence frequencies to Pm6, Pm7, and Pm5+8 were high throughout the 19-year period, in contrast with that to Pm5+6, which was consistently at a low level. The most significant change in the population was observed for virulence to the Pm2+4b+6 gene combination, with an increasing frequency of virulence to this gene combination over the years. High virulence complexity and genetic diversity of the population are the most influential factors for the damaging epidemics that this pathogen can cause.

AA-amyloidosis in captive northern tree shrews (Tupaia belangeri)

A high prevalence of AA-amyloidosis was identified in a breeding colony of northern tree shrews ( Tupaia belangeri) in a retrospective analysis, with amyloid deposits in different organs being found in 26/36 individuals (72%). Amyloid deposits, confirmed by Congo red staining, were detected in kidneys, intestines, skin, and lymph nodes, characteristic of systemic amyloidosis. Immunohistochemically, the deposited amyloid was intensely positive with anti-AA-antibody (clone mc4), suggesting AA-amyloidosis. The kidneys were predominantly affected (80%), where amyloid deposits ranged from mild to severe and was predominantly located in the renal medulla. In addition, many kidneys contained numerous cysts with atrophy of the renal parenchyma. There was no significant association between concurrent neoplastic or inflammatory processes and amyloidosis. The lack of distinctive predisposing factors suggests a general susceptibility of captive T. belangeri to develop amyloidosis. Clinical and laboratory findings of a female individual with pronounced kidney alterations were indicative of renal failure. The observed tissue tropism with pronounced kidney alterations, corresponding renal dysfunction, and an overall high prevalence suggests amyloidosis as an important disease in captive tree shrews.

Pilot study of preventive homeopathic treatment for colibacillosis in a swine farm in the State of São Paulo, Brazil

Diarrhea has become an economically important disease in pigs due to intensive management system which has been used. Escherichia coli is the most important etiological agent of neonatal and post weaning diarrhea in swine colibacillosis and the greater impact of the disease in pigs. The demand of consumers seeking meat without chemical residues and the prohibition of the use of antibiotics and chemotherapeutics in swine production has led to seek an alternative medicine for preventive and therapeutic treatments in swine breeding. This study was carried out in a commercial farm in São Paulo state. Stool samples were collected from five piglets presenting diarrhea and examined for the presence of Escherichia coli. Concomitantly, a detailed interview was done with the owner, about all clinical information useful to choose the best homeopathic medicine, using repertory method. Subsequently, four groups were formed consisting of 11-12 piglets each: a control group (antimicrobial used in the farm routine for treatment of diarrhea), a group treated with the chosen homeopathic medicine - China officinalis 30 CH - a group treated with E. coli biotherapic 30 CH (medicine made from E. coli strains collected and isolated from the same farm) and a group treated with both homeopathic and biotherapic E. coli medicines. There was no statistical difference in the number of animals presenting diarrhea among groups, but China treated pigs showed greater weight gain compared to the other three groups (Fisher test, p = 0.0001), despite the incidence of diarrhea. In conclusion, this preliminary study suggests that the use of repertory chosen homeopathic medicines could improve productivity in swine farms even though clinical manifestations of diarrhea occur.

Development and comparison of loop-mediated isothermal amplification with quantitative PCR for the specific detection of Saprolegnia spp.

Saprolegniasis is an important disease in freshwater aquaculture, and is associated with oomycete pathogens in the genus Saprolegnia. Early detection of significant levels of Saprolegnia spp. pathogens would allow informed decisions for treatment which could significantly reduce losses. This study is the first to report the development of loop-mediated isothermal amplification (LAMP) for the detection of Saprolegnia spp. and compares it with quantitative PCR (qPCR). The developed protocols targeted the internal transcribed spacer (ITS) region of ribosomal DNA and the cytochrome C oxidase subunit 1 (CoxI) gene and was shown to be specific only to Saprolegnia genus. This LAMP method can detect as low as 10 fg of S. salmonis DNA while the qPCR method has a detection limit of 2 pg of S. salmonis DNA, indicating the superior sensitivity of LAMP compared to qPCR. When applied to detect the pathogen in water samples, both methods could detect the pathogen when only one zoospore of Saprolegnia was present. We propose LAMP as a quick (about 20–60 minutes) and sensitive molecular diagnostic tool for the detection of Saprolegnia spp. suitable for on-site applications.

Coding-Complete Sequences of Recombinant Lumpy Skin Disease Viruses Collected in 2020 from Four Outbreaks in Northern Vietnam

Lumpy skin disease virus (LSDV) causes a severe, systemic, and economically important disease in cattle. Here, we report coding-complete sequences of recombinant LSDVs from four outbreaks in October and November 2020 in northeastern Vietnam.

Malarial Epidemiology among Patients in Al-Medina Al-Munawara, KSA

Worldwide, malaria is the most important disease caused by parasites and responsible for a yearly estimation of 225 million clinical cases. The risk of the disease covers almost half of the world’s population and the annual death has been estimated as 800.000. Children under five years of age are mainly affected. Pregnant women and adults with immunosuppression become victims of cerebral manifestations or anaemia and frequently die. Almost 40% of the world's population is at risk to acquire the infection. Human malaria is caused by four Plasmodium species among which the most prevalent is Plasmodium falciparum. Because of the higher global prevalence, morbidity and mortality rate of P. falciparum, most research efforts on malaria pathogenesis have been focused on this species. Recent studies have reported the clinical outcomes that originate from regions where P. falciparum and P. vivax are equally prevalent. This in turn could make the clinical tools inappropriate for use in managing vivax mono infections. Thus, the present study was aimed to identify the epidemiology and clinical features of the malarial cases of the Referral laboratory, Al Madinah, Saudi Arabia. A retrospective case series study was conducted among the patients reported from January 2016 to December 2016 using a specially designed data collection form. Out of the 182 confirmed cases, 143 were non-saudi and 39 were Saudi cases. Most of the cases reported in the month of September due to seasonal change. Gender distribution showed a higher dominance of male patients compared to females. No cases were reported to be caused due to P.malariae. The predominant species was found to be P.Vivax (87%) while P.falciparum with only 13% incidence. Further investigations in large sample sizes are recommended to explore the other aspects in reducing the malaria burden.

Molecular characterization and overexpression of the difenoconazole resistance gene CYP51 in Lasiodiplodia theobromae field isolates

Stem-end rot (SER) caused by Lasiodiplodia theobromae is an important disease of mango in China. Demethylation inhibitor (DMI) fungicides are widely used for disease control in mango orchards. The baseline sensitivity to difenoconazole of 138 L. theobromae isolates collected from mango in the field in 2019 was established by the mycelial growth rate method. The cross-resistance to six site-specific fungicides with different modes of action were investigated using 20 isolates randomly selected. The possible mechanism for L. theobromae resistance to difenoconazole was preliminarily determined through gene sequence alignment and quantitative real-time PCR analysis. The results showed that the EC50 values of 138 L. theobromae isolates to difenoconazole ranged from 0.01 to 13.72 µg/mL. The frequency of difenoconazole sensitivity formed a normal distribution curve when the outliers were excluded. Difenoconazole showed positive cross-resistance only with the DMI tebuconazole but not with non-DMI fungicides carbendazim, pyraclostrobin, fludioxonil, bromothalonil, or iprodione. Some multifungicide-resistant isolates of L. theobromae were found. Two amino acid substitutions (E209k and G207A) were found in the CYP51 protein, but they were unlikely to be related to the resistance phenotype. There was no alteration in the promoter region of the CYP51 gene. However, difenoconazole significantly increased the expression of the CYP51 gene in the resistant isolates compared to the susceptible isolates. These results are vital to develop effective mango disease management strategies to avoid the development of further resistance.