Effect of Soil Temperature on Reproduction of Root-knot Nematodes in Flue-cured Tobacco with Homozygous and/or Resistance Genes.

Most commercial flue-cured tobacco cultivars contain the resistance gene, which provides resistance to races 1 and 3 of and race 1 of . A number of cultivars now possess a second root-knot resistance gene, . High soil temperatures have been associated with a breakdown of root-knot resistance genes in a number of crops.

Perspective on the development of synthetic microbial community (SynCom) biosensors.

Synthetic microbial community (SynCom) biosensors are a promising technology for detecting and responding to environmental cues and target molecules. SynCom biosensors use engineered microorganisms to create a more complex and diverse sensing system, enabling them to respond to stimuli with enhanced sensitivity and accuracy. Here, we give a definition of SynCom biosensors, outline their construction workflow, and discuss current biosensing technology.

Integration of high-throughput omics technologies in medicinal plant research: The new era of natural drug discovery.

Medicinal plants are natural sources to unravel novel bioactive compounds to satisfy human pharmacological potentials. The world's demand for herbal medicines is increasing year by year; however, large-scale production of medicinal plants and their derivatives is still limited. The rapid development of modern technology has stimulated multi-omics research in medicinal plants, leading to a series of breakthroughs on key genes, metabolites, enzymes involved in biosynthesis and regulation of active compounds.

Brassica Cover Crops and Natural Infestation of Peat-Based Potting Mix May Increase Powdery Scab Risk on Potato.

is a soilborne plasmodiophorid that causes powdery scab and root gall formation in potato. In this study, 18 cover crops suitable for use in dry, high-altitude potato production regions were assessed in potting mix trials to determine whether these cover crops altered population levels. Although appeared to invade roots of all plant species tested, the pathogen was unable to complete its life cycle on 11 of 18 cover crops based on postharvest qPCR and microscopy results.

Diversity of Species Recovered from Float-Bed Tobacco Transplant Production Greenhouses.

Pythium diseases are common in hydroponic crop production and often threaten the greenhouse production of cucumber, tomato, lettuce, and other crops. In tobacco transplant production, where float-bed hydroponic greenhouses are commonly used, Pythium diseases can cause up to 70% seedling loss. However, there have been few comprehensive studies on the composition and diversity of communities in tobacco greenhouses.

Dominant remodelling of cattle rumen microbiome by (tall fescue) KY-31 carrying a fungal endophyte.

Tall fescue KY-31 is an important primary forage for beef cattle. It carries a fungal endophyte that produces ergovaline, the main cause of tall fescue toxicosis that leads to major revenue loss for livestock producers. The MaxQ, an engineered cultivar, hosts an ergovaline nonproducing strain of the fungus and consequently is nontoxic.

Reproduction of race 2 on flue-cured tobacco with putative resistance derived from .

Chemical controls for root-knot nematodes are increasingly restricted due to environmental and human health concerns. Host resistance to these nematodes is key to flue-cured tobacco production in Virginia. Resistance to races 1 and 3, and race 1 of is imparted by the gene which is widely available in commercial flue-cured tobacco.

Reproduction of race 2 on Flue-cured tobacco possessing resistance genes Rk1 and/or Rk2.

Resistance to races 1 and 3 and race 1 of is imparted to flue-cured tobacco by the gene race 2 is not controlled by and has become prevalent in Virginia. A second form of resistance effective against , , is also increasingly available commercially. Greenhouse and field trials including a root-knot susceptible cultivar, cultivars homozygous for or , and cultivars possessing both genes were conducted in 2018 and 2019 to investigate the effect of and/or on parasitism and reproduction of race 2.

Validation of the Strawberry Advisory System in the Mid-Atlantic Region.

Anthracnose fruit rot (AFR) and Botrytis fruit rot (BFR) are primary diseases affecting strawberry (), which typically drive fungicide applications throughout the growing season. The Strawberry Advisory System (StAS), a disease forecasting tool, was originally developed in Florida to better time the fungicide sprays by monitoring AFR and BFR infection risk based on leaf wetness and temperature input in real-time. Thirteen field trials were conducted in Maryland and Virginia between 2017 and 2019 to evaluate the StAS performance in the Mid-Atlantic region.

Quantitative Real-Time PCR Analysis of Individual Flue-Cured Tobacco Seeds and Seedlings Reveals Seed Transmission of Tobacco Mosaic Virus.

Tobacco mosaic virus (TMV) is an extensively studied RNA virus known to infect tobacco () and other solanaceous crops. TMV has been classified as a seedborne virus in tobacco, with infection of developing seedlings thought to occur from contact with the TMV-infected seed coat. The mechanism of TMV transmission through seed was studied in seed of the K 326 cultivar of flue-cured tobacco.

Nutritional composition and in vitro digestibility of grass and legume winter (cover) crops.

In dairy farming systems, growing winter crops for forage is frequently limited to annual grasses grown in monoculture. The objectives of this study were to determine how cropping grasses alone or in mixtures with legumes affects the yield, nutritional composition, and in vitro digestibility of fresh and ensiled winter crops and the yield, nutritional composition, and in vitro digestibility of the subsequent summer crops. Experimental plots were planted with 15 different winter crops at 3 locations in Virginia.

Reproduction of Meloidogyne incognita Race 3 on Flue-cured Tobacco Homozygous for Rk1 and/or Rk2 Resistance Genes.

Most commercial tobacco cultivars possess the Rk1 resistance gene to races 1 and 3 of Meloidogyne incognita and race 1 of Meloidogyne arenaria, which has caused a shift in population prevalence in Virginia tobacco fields toward other species and races. A number of cultivars now also possess the Rk2 gene for root-knot resistance. Experiments were conducted in 2013 to 2014 to examine whether possessing both Rk1 and Rk2 increases resistance to a variant of M.

Induction and Maintenance of Systemic Acquired Resistance by Acibenzolar-S-Methyl in Three Cultivated Tobacco Types.

Induction and maintenance of systemic acquired resistance (SAR) in 'N' gene containing burley, flue-cured, and oriental tobacco cultivars were assessed by monitoring decreases in the number of local lesions caused by Tobacco mosaic virus (TMV) following treatment with acibenzolar-S-methyl (ASM). Leaf samples were collected from lower, middle, and top positions on seedlings at 3-day intervals over 21 days following ASM treatment and subsequent inoculation with TMV under laboratory conditions. Local lesion number for each leaf was recorded 7 days postinoculation.

Population Structure, Mating Type, and Mefenoxam Sensitivity of Phytophthora nicotianae in Virginia Tobacco Fields.

Black shank is an important disease of tobacco (Nicotiana tabacum) caused by the fungus-like organism, Phytophthora nicotianae. Three physiological races (0, 1, and 3) have been documented in the United States. Shifts in the pathogen population structure have become a concern due to the widespread use of cultivars possessing resistance to race 0 arising from a single gene (Ph or Ph).

Effects of Ph gene-associated versus induced resistance to tobacco cyst nematode in flue-cured tobacco.

Effects of the systemic acquired resistance (SAR)-inducing compound acibenzolar-S-methyl (ASM) and the plant-growth promoting rhizobacterial mixture Bacillus subtilis A13 and B. amyloliquefaciens IN937a (GB99+GB122) were assessed on the reproduction of a tobacco cyst nematode (TCN- Globodera tabacum solanacearum) under greenhouse conditions. Two sets of two independent experiments were conducted, each involving soil or root sampling.

Biological and chemical induction of resistance to the Globodera tabacum solanacearum in oriental and flue-cured tobacco (Nicotiana tabacum L.).

The effects of acibenzolar-S-methyl (ASM) and four combinations of plant growth-promoting rhizobacteria (PGPR) on the reproduction of a tobacco cyst nematode, Globodera tabacum solanacearum, and growth of Nicotiana tabacum (cv. K326 and Xanthi) were tested under greenhouse and field conditions. The PGPR included combinations of Bacillus subtilis A13 with B.

Effect of a Chromosome Segment Marked by the Ph Gene for Resistance to Phytophthora nicotianae on Reproduction of Tobacco Cyst Nematodes.

Host resistance is an important strategy for managing Globodera tabacum subsp. solanacearum and G. tabacum subsp.

Inheritance of Phytophthora root rot resistance in red raspberry determined by generation means and molecular linkage analysis.

Classical and molecular methodologies were used to determine the inheritance of Phytophthora root rot (PRR) resistance in red raspberry. The varieties 'Latham' and 'Titan,' resistant and susceptible, respectively, were used to create F(1), F(2), B(1), B(2), and S(1) populations for analysis. Generational means analysis was used to calculate the components of genetic variation and estimates of narrow and broad sense heritability for the plant disease index and the incidence of petiole lesions.

Influence of substrate type and temperature on the developmental morphology of Pandora neoaphidis (Zygomycetes: entomophthorales), a pathogen of the tobacco aphid (Homoptera: aphididae).

Developmental morphology of Pandora neoaphidis was observed on the surfaces of the tobacco aphid, Myzus nicotianae, tobacco leaves (Nicotiana tabacum), and glass coverslips at 13 and 20 degrees C for 12 and 24 h postinoculation. Pandora neoaphidis responded similarly on the two living substrates, but differed on the inert coverslips. The proportions of ellipsoid conidia (primary and secondary) were similar on all substrates.