Pathogens are biological organisms like fungi, bacteria, nematodes, and viruses that can cause clinical manifestations, drastically lower plant productivity and quality, or even kill plants.
Bacteria called phytoplasmas can enter the vascular tissues of plants and cause a variety of crop diseases.
A new study focuses on the tiny insects that spread the bacterial growth from plant to plant, as opposed to the majority of phytoplasma studies that start by examining plants that exhibit disease symptoms.
The study found new connections between leafhoppers and phytoplasmas known to harm crop plants by identifying new phytoplasma strains and testing DNA from archival leafhopper specimens collected in natural areas.
Plant pathogens
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Numerous methods exist for introducing and dispersing pathogens among host plants.
Wind, rain, and soil-borne spores from fungi and bacteria can all spread from one plant to another, as per InTeGrate.
When an insect feeds on an infected host plant and then moves on to feed on an uninfected plant, it can transmit or infect a plant with a pathogen.
Infected seeds, transplants, contamination, irrigation water, and people can all be sources of pathogen transmission.
Leafhoppers
Any of the tiny, elongated, frequently exquisitely colored, and marked sap-sucking insects of the large family Cicadellidae of the order Homoptera are known as leafhoppers, as per Britannica.
They can be found on almost all kinds of plants, but different species have different host requirements.
Even though a leafhopper on its own won't harm a plant, a population of them can be a serious economic pest.
They could harm the plant by removing sap, destroying chlorophyll, spreading diseases, or curling leaves as a result of their feeding.
The study, led by INHS State Entomologist Christopher Dietrich and postdoctoral researcher Valeria Trivellone, was published in the journal Biology and is the first to glance for phytoplasmas in insects from natural areas.
It is also the first to detect and characterize phytoplasmas in leafhoppers using a variety of molecular methods, as per ScienceDaily.
The researchers used leafhopper specimens from the INHS insect collection for the latest study.
To categorize these insects' genetic relatedness and evolutionary history, Dietrich gathered many of them over 25 years.
The researchers looked at 407 different species of leafhoppers that were gathered in less developed parts of the world. The samples came from Australia, Africa, Asia, Europe, North and South America, and Africa.
The team used both conventional and cutting-edge sequencing techniques to process each specimen, extracting the total DNA from each.
According to the researchers, these methods are less expensive and more educational than conventional methods.
23 leafhoppers provided the researchers with useful phytoplasma sequence data, and 41 of the insects collected during the sampling tested positively for phytoplasmas.
The aster yellows disease, which prevents photosynthesis and lowers the productivity of numerous crop plants, is one of the phytoplasmas.
Numerous new species of leafhoppers that had not previously been recognized as disease vectors were found to carry these phytoplasmas.
Several new bacterial strains were discovered because of the study, which also discovered phytoplasmas in parts of the world where such diseases still hadn't previously been reported.
It also discovered unreported connections between a few phytoplasmas and specific species of leafhopper.
Scientists lack the tools to target specific bacteria in asymptomatic plants to stop disease outbreaks, so attempting to control phytoplasmas requires using pesticides to eradicate the insect vectors.
The discoveries are consistent with those in newly emerging infectious diseases that affect humans and are derived from wildlife.
