New report of Citrus indica Yu. Tanaka,a wild progenitor species of citrus from Dailong Forest,Manipur, and recommendation for its conservation

Genetic Resources and Crop Evolution - Citrus indica Yu. Tanaka is a wild and endangered progenitor species of citrus endemic to North East (NE) India. It is reported to be restricted to Nokrek...     

Fat but slim: Criteria of seed attractiveness for earthworms

Earthworms were shown to significantly affect seeds and seedlings survival via their ingestion and digestion for nutritive purposes. Such selective feeding of earthworms on plant seeds is likely to favour certain plant species and to affect seed bank composition, plant recruitment and plant community structure. Relationships between earthworms and seeds, particularly seed traits that determine attractiveness of seeds for earthworms, are yet to be determined. In this study, the influence of six seed traits was tested on the ingestion, digestion and germination of seeds by two earthworm species (Lumbricus terrestris, anecic and Satchellius mammalis, epigeic). The seed traits tested were their length, width, weight, shape, oil content and the presence of trichomes on their surface. Each earthworm species was introduced into a microcosm with eleven seed species from a chalk grassland that represented those different traits. Ingested, digested and germinated seeds were counted after voiding the guts of the earthworms. Univariate and multivariate analyses showed that seed length, width, weight and seed oil content could significantly affect the ingestion of seeds for both earthworm species. Seed width and seed oil content were the two traits that influenced the digestion of seeds the most, but only for L. terrestris. We also found that seed ingestion was earthworm species-specific but we found no correlation between earthworm traits and number of ingested or digested seeds. Few seeds germinated from L. terrestris casts and no seeds germinated from S. mammalis casts. Implications in terms of plant evolution strategies are further discussed.     

Identification and characterization of Phoma tracheiphila mutants impaired in pathogenicity following Agrobacterium-mediated mutagenesis

Mal secco disease, caused by the pathogenic fungus Phoma tracheiphila, is a devastating disease of susceptible citrus species, especially lemon. To study the molecular interactions between the pathogen and its host, a method for identifying the genes involved in pathogenicity is needed. This work describes the transformation of P. tracheiphila phialoconidia by Agrobacterium tumefaciens, and the generation of mutated P. tracheiphila isolates exhibiting reduced virulence on rough lemon seedlings. A rapid, replicable, and reliable method for screening P. tracheiphila mutants to assess their virulence by using rough lemon seedlings was developed. Among 2263 transformants obtained, three were non-virulent and 43 displayed reduced virulence. In addition, one of the transformants, which exhibited virulence similar to that of the wild type, was used for in planta visualization of the fungus progression through the plant xylem. To our knowledge, this is the first report of A. tumefaciens-mediated transformation of P. tracheiphila, and subsequent screening of the transformants to identify non-virulent mutants.     

Treatment of dairy cows with PGF2α or NSAID,in combination with antibiotics,in cases of postpartum uterine inflammation

Background

The aim of the study was to test the effect of two treatments in cases of acute puerperal metritis (APM) and clinical metritis (CM).

Methods

Cows with APM and CM (n = 40)) were matched according to plasma fibrinogen levels (Fb) into three groups. Two negative control groups D (n = 11) and E (n = 17) were composed of healthy cows. The proportion of animals with APM and CM was similar within the groups. Treatment was started on the 3rd day postpartum (PP). In group A (n = 15), intramuscular (i.m.) administration of ceftiofur was used for five days in combination with flunixin for three days. Group B (n = 15) received i.m. administration of ceftiofur for five days followed by two injections of prostaglandin F2_α, with an interval of 8 h, on the 8th day PP. Group C (n = 10) served as a control group with no treatment. The general health status, body temperature (BT) and vaginal discharge were evaluated daily. Endometrial biopsies for bacteriology were taken once a week for seven weeks PP. Blood samples for the analysis of acute phase proteins were collected once a week for six weeks PP. Samples for progesterone analysis were taken twice a week for seven weeks PP. Fertility performance data were recorded.

Results

The area under the curve of BT was higher in group B than in group D cows (P < 0.05). No differences were found for vaginal discharge. There were no differences in bacterial growth, start of ovarian activity or serum amyloid-A or fibrinogen levels among the groups. The haptoglobin concentration was higher in the first and second weeks PP in group B compared with the other groups (P < 0.05). The number of days open was higher in group A than in both groups B and D (P < 0.05). The pregnancy rate after the first two services was higher (P < 0.05) in groups B and D than in groups A and C. The number of services per pregnancy was lower in group B than in group C (P < 0.05).

Conclusions

Regardless of more severe uterine inflammation found in animals from group B, these cows showed the same fertility parameters as healthy animals.     

Early effects of COVID‐19 on US fisheries and seafood consumption

The US seafood sector is susceptible to shocks, both because of the seasonal nature of many of its domestic fisheries and its global position as a top importer and exporter of seafood. However, many data sets that could inform science and policy during an emerging event do not exist or are only released months or years later. Here, we synthesize multiple data sources from across the seafood supply chain, including unconventional real‐time data sets, to show the relative initial responses and indicators of recovery during the COVID‐19 pandemic. We synthesized news articles from January to September 2020 that reported effects of COVID‐19 on the US seafood sector, including processor closures, shortened fishing seasons and loss of revenue. Concerning production and distribution, we assessed past and present landings and trade data and found substantial declines in fresh seafood catches (?40%), imports (?37%) and exports (?43%) relative to the previous year, while frozen seafood products were generally less affected. Google search trends and seafood market foot traffic data suggest consumer demand for seafood from restaurants dropped by upwards of 70% during lockdowns, with recovery varying by state. However, these declines were partially offset by an increase (270%) in delivery and takeout service searches. Our synthesis of open‐access data sets and media reports shows widespread, but heterogeneous, ramifications of COVID‐19 across the seafood sector, implying that policymakers should focus support on states and sub‐sectors most affected by the pandemic: fishery‐dependent communities, processors, and fisheries and aquaculture that focus on fresh products.     

Effect of soil amendments and biological control agents (BCAs) on soil-borne root diseases caused by <Emphasis Type="Italic">Pyrenochaeta lycopersici</Emphasis> and <Emphasis Type="Italic">Verticillium albo-atrum</Emphasis> in organic greenhouse tomato production systems

The effect of different soil amendments and biological control agents on soil-borne root diseases that cause significant economic losses in organic and other soil-based tomato production systems (Pyrenochaeta lycopersici and Verticillium albo-atrum) was compared. Organic matter inputs (fresh Brassica tissue, household waste compost and composted cow manure) significantly reduced soil-borne disease severity (measured as increased root fresh weight) and/or increased tomato fruit yield, with some treatments also increasing fruit number and/or size. Soil biological activity also increased with increasing organic matter input levels and there were significant positive correlations between soil biological activity, root fresh weight and fruit yield. This indicates that one mechanism of soil-borne disease control by organic matter input may be increased competition by the soil biota. Chitin/chitosan products also significantly reduced soil-borne disease incidence and increased tomato fruit yield, number and/or size, but had no effect on soil biological activity. Biological control products based on Bacillus subtilis and Pythium oligandrum and commercial seaweed extract (Marinure) and fish emulsion (Nugro)-based liquid fertilisers had no positive effect on soil-borne disease incidence and fruit yield, number and size. The use of ‘suppressive’ organic matter inputs alone or in combination with chitin/chitosan soil amendments can therefore be recommended as methods to control soil-borne diseases in organic and other soil-based production systems.     

Prevalence of bovine viral diarrhea virus (BVDV) in persistently infected cattle and BVDV subtypes in affected cattle in beef herds in south central United States

The prevalence of bovine viral diarrhea virus (BVDV) in persistently infected (PI) cattle in beef breeding herds was determined using 30 herds with 4530 calves. The samples were collected by ear notches and tested for BVDV antigens using immunohistochemistry (IHC) and antigen capture enzyme-linked immunosorbent assay (ACE). Animals with initial positives on both IHC and ACE were sampled again using both tests and serums were collected for viral propagation and sequencing of a viral genomic region, 5′-untranslated region (5′-UTR) for viral subtyping. Samples were also collected from the dams of PI calves. There were 25 PI calves from 4530 samples (0.55%) and these PI calves were from 5 of the 30 herds (16.7%). Two herds had multiple PI calves and 3 herds had only 1 PI calf. Only 1 of the 25 dams with a PI calf was also PI (4.0%). The subtype of all the PI isolates was BVDV1b. Histories of the ranches indicated 23 out of 30 had herd additions of untested breeding females. Twenty-four of the 30 herds had adult cowherd vaccinations against BVDV, primarily using killed BVDV vaccines at pregnancy examination.