Effects of bacteriocin and organic acid on growth performance,small intestine histomorphology,and microbiology in Japanese quails (Coturnix coturnix japonica)

Tropical Animal Health and Production - In this study, 600 1-day-old Japanese quail chicks (Coturnix coturnix japonica) were used to investigate the effects of bacteriocin and organic acids on...     

Real-time quantitative PCR assays for evaluation of soybean varieties for resistance to the stem and root rot pathogen Phytophthora sojae

Phytophthora root and stem rot caused by Phytophthora sojae is one of the most destructive disease of soybeans in the world. Effective management of the disease depends on selection and use of soybean varieties resistant to the disease. Fast and reliable procedures are vital to screen soybean varieties against the pathogen. Novel real-time quantitative (qPCR) assays were developed for both absolute and relative quantification of P. sojae in infected root tissues. QPCR assays were based on the detection of the internal transcribed spacer (ITS) gene of the pathogen and 18S ribosomal gene of the host plant. Absolute qPCR allowed the detection of as low as 10 femtograms (fg) of P. sojae DNA in soybean roots. Relative qPCR, employing the comparative threshold cycle (Ct) method, was effective and reliable for quantification of P. sojae DNA normalized to plant DNA in infected soybean root tissues. P. sojae DNA quantities detected in both qPCR assays had high correlations with disease severity index (DSI) ratings of soybean varieties. QPCR assays developed in this study were useful for determination of the levels of P. sojae DNA in different varieties of soybean and for evaluation of them for relative resistance to the pathogen.     

Eco-geographic distribution of <Emphasis Type="Italic">Cicer isauricum</Emphasis> P.H. Davis and threats to the species

Wild Cicer species are considered as useful genetic resources for resistance to biotic and abiotic stresses due to limited resistance in cultivated chickpeas. As a wild perennial species in the genus Cicer L., Cicer isauricum P.H. Davis is an endemic species to Turkey and endangered status according to the International Union for Conservation of Nature criteria. Here we report on its eco-geographic distribution and environmental stresses that affect the species, and advocate for its in situ and ex situ conservation. A new population of the species was discovered in Geyikbay?r?, Güllük Mountains in Antalya, Turkey. Cicer isauricum not only suffers from significant biotic stresses such as ascochyta blight [Ascochyta rabiei (Pass.) Labr.], pod borer (Helicoverpa armigera Hübner) and broomrape (Orobanche sp.), but is also subjected to drought and heat stress in its habitat. Infection with ascochyta blight in natural habitats was diagnosed by molecular techniques, and pod borer and broomrape were observed only phenotypically. PCR amplification of the internal transcribed spacer region of genomic DNA from cultured fungal isolates, yielded sequences with 100% nucleotide identity with the corresponding sequence in GeneBank for Didymella rabiei Kovachevski (anamorph: A. rabiei). The pathogen may have co-evolved with C. isauricum in the newly discovered site. Because C. isauricum is exposed to drought and accompanying heat stress in its natural habitat, it appears able to tolerate heat stress up to 45 °C during podding stage and terminal drought in late summer from its woody, deep rooting. C. isauricum bears multiple flowers per axil, a potentially useful trait in cultivated chickpea. In conclusion, C. isauricum is a potential genetic source for resistance to biotic and abiotic stresses, in need of greater protection due to its endangered status.     

Molecular identification,characterization and transmission of phytoplasmas associated with sesame phyllody in Turkey

Phyllody is a destructive disease of sesame in Turkey. The disease has been causing significant economic losses by stunting the plants and altering their floral parts into leafy structures with no capsule and hence no seeds in sesame fields of the country. This research was undertaken to examine symptomatology, etiology, taxonomy and transmission of two recently discovered phyllody phytoplasmas infecting sesame in Turkey. Direct and nested PCR amplifications of 16S rRNA gene with the phytoplasma-specific universal primers P1/P7 and R16F2n/R2, respectively were employed for identification of the phytoplasmas associated with sesame phyllody. Phytoplasma-specific PCR amplicons of 1.8 kb and 1.2 kb were amplified only from symptomatic sesame plants and insect vector samples. Sequencing of the PCR amplicons and computer simulated restriction fragment length polymorphism analysis allowed classification of the phytoplasmas with pigeon pea witches’-broom (16SrIX-C) and peanut witches’-broom (16SrII-D) groups. The sequence homology and phylogenetic analyses further confirmed this classification. Among the insects collected from the sesame fields, the leafhopper Orosius orientalis Matsumara (Syn: O. albicinctus Distant) was the only vector proven to transmit the sesame phyllody phytoplasmas from diseased to healthy sesame plants in transmission assays. The results demonstrated that the 16SrIX-C and 16SrII-D group phytoplasmas were the agent of sesame phyllody and O. orientalis was the vector insect of the disease in Turkey.     

Screening,selection and real-time qPCR validation for phytoplasma resistance in sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.)

Phyllody is one of the most destructive diseases of sesame and causes serious yield losses worldwide. The present research was conducted to identify phyllody resistant genotypes in sesame. A total of 542 sesame genotypes were screened for the disease resistance in the field using a disease incidence scale of 1–5 in the year 2012. Three hundred four genotypes showing high disease intensity were eliminated under artificially infected field conditions. In the year 2013, only 30 out of 238 accessions were determined as potential resistant genotypes based on the disease incidence scale. These selected genotypes were further evaluated for confirmation of the resistance in greenhouse conditions using the phytoplasma-infected vector insects under choice and no-choice conditions. Furthermore, real-time qPCR was employed for detection and quantification of phytoplasmas to select true resistant genotypes. The sesame accessions ACS38 and ACS102 were identified as resistant to the disease after evaluation in field, greenhouse and qPCR assays. This work is one of the most comprehensive studies to select genotypes resistant to the diseases caused by phytoplasmas.