Genomic variation in pepper vein yellows viruses in Australia, including a new putative variant, PeVYV-10.

Since the first identification and full sequence of the polerovirus pepper vein yellows virus in Australia in 2016, virus surveys of crops and weeds have sporadically identified PeVYV in different hosts and locations. Genomic comparisons of 14 PeVYV-like isolates using RT-PCR products spanning the 3' end of the RdRp region (ORF 2), the intergenic region, ORF 3a, ORF 4, and ORF 3 (1388 nt) showed that four of the PeVYV isolates might be a new variant or PeVYV-like virus. From six PeVYV-positive plants, eight PeVYV-like sequences were obtained by high-throughput sequencing, as two hosts, 5352 and 5634, contained two slightly different PeVYV-like isolates.

Development of a Novel Tissue Blot Hybridization Chain Reaction for the Identification of Plant Viruses.

Assays for the high throughput screening of crops for virus monitoring need to be quick, easy, and low cost. One method involves using tissue blot immunoassays (TBIA), where plant stems are blotted onto nitrocellulose membrane and screened with available antibodies against a range of viruses. TBIAs are inexpensive but limited by antibody availability and specificity.

Biology and genetic diversity of phasey bean mild yellows virus, a common virus in legumes in Australia.

This study examined the natural and experimental host range and aphid and graft transmission of the tentative polerovirus phasey bean mild yellows virus (PBMYV). Eleven complete coding sequences from PBMYV isolates were determined from a range of hosts and locations. We found two genetically distinct variants of PBMYV.

Genetic diversity and recombination between turnip yellows virus strains in Australia.

Disease outbreaks caused by turnip yellows virus (TuYV), a member of the genus Polerovirus, family Luteoviridae, regularly occur in canola and pulse crops throughout Australia. To understand the genetic diversity of TuYV for resistance breeding and management, genome sequences of 28 TuYV isolates from different hosts and locations were determined using high-throughput sequencing (HTS). We aimed to identify the parts of the genome that were most variable and clarify the taxonomy of viruses related to TuYV.

Complete Genome Sequence of a New Mastrevirus, Chickpea Redleaf Virus 2, from Australia.

We present here the complete genome sequence of a novel mastrevirus isolated from (chickpea) from Australia. We propose the name chickpea redleaf virus 2.

Faba bean polerovirus 1 (FBPV-1); a new polerovirus infecting legume crops in Australia.

A new polerovirus species with the proposed name faba bean polerovirus 1 (FBPV-1) was found in winter legume crops and weeds in New South Wales, Australia. We describe the complete genome sequence of 5,631 nucleotides, containing all putative open reading frames, from two isolates, one from faba bean (Vicia faba) and one from chickpea (Cicer arietinum). FBPV-1 has a genome organization typical of poleroviruses with six open reading frames.

LATERAL BRANCHING OXIDOREDUCTASE acts in the final stages of strigolactone biosynthesis in Arabidopsis.

Strigolactones are a group of plant compounds of diverse but related chemical structures. They have similar bioactivity across a broad range of plant species, act to optimize plant growth and development, and promote soil microbe interactions. Carlactone, a common precursor to strigolactones, is produced by conserved enzymes found in a number of diverse species.

Two Complete Genome Sequences of Phasey Bean Mild Yellows Virus, a Novel Member of the Luteoviridae from Australia.

We present here the complete genome sequences of a novel polerovirus from Trifolium subterraneum (subterranean clover) and Cicer arietinum (chickpea) and compare these to a partial viral genome sequence obtained from Macroptilium lathyroides (phasey bean). We propose the name phasey bean mild yellows virus for this novel polerovirus.

Genome-wide association analysis and differential expression analysis of resistance to Sclerotinia stem rot in Brassica napus.

Brassica napus is one of the most important oil crops in the world, and stem rot caused by the fungus Sclerotinia sclerotiorum results in major losses in yield and quality. To elucidate resistance genes and pathogenesis-related genes, genome-wide association analysis of 347 accessions was performed using the Illumina 60K Brassica SNP (single nucleotide polymorphism) array. In addition, the detached stem inoculation assay was used to select five highly resistant (R) and susceptible (S) B.

Cadmium stress alters the redox reaction and hormone balance in oilseed rape (Brassica napus L.) leaves.

In order to understand the physiological response of oilseed rape (Brassica napus L.) leaves to cadmium (Cd) stress and exploit the physiological mechanisms involved in Cd tolerance, macro-mineral and chlorophyll concentrations, reactive oxygen species (ROS) accumulation, activities of enzymatic antioxidants, nonenzymatic compounds metabolism, endogenous hormonal changes, and balance in leaves of oilseed rape exposed to 0, 100, or 200 μM CdSO4 were investigated. The results showed that under Cd exposure, Cd concentrations in the leaves continually increased while macro-minerals and chlorophyll concentrations decreased significantly.

Overexpression of a gibberellin inactivation gene alters seed development, KNOX gene expression, and plant development in Arabidopsis.

We have examined the role of gibberellins (GAs) in plant development by expression of the pea GA 2-oxidase2 (PsGA2ox2) cDNA, which encodes a GA inactivating enzyme, under the control of the MEDEA (MEA) promoter. Expression of MEA:PsGA2ox2 in Arabidopsis caused seed abortion, demonstrating that active GAs in the endosperm are essential for normal seed development. MEA:PsGA2ox2 plants had reduced ovule number per ovary and exhibited defects in phyllotaxy and leaf morphology which were partly suppressed by GA treatment.

Functional analysis of HvSPY, a negative regulator of GA response, in barley aleurone cells and Arabidopsis.

SPINDLY (SPY) is an important regulator of plant development, and consists of an N-half tetratricopeptide repeat (TPR) domain containing 10 TPR motifs and a C-half catalytic domain, similar to O-GlcNAc transferase (OGT) of animals. The best characterised role of SPY is a negative regulator of GA signalling, and all known spy alleles have been isolated based on increased GA response. Of the eight alleles that directly affect the TPR domain, all alter TPRs 6, 8 and/or 9.