Plant Pathology and world Plant Problems

😔

is caused by either a bacterium or a fungus infection.

Depending on the cause of the rot, whether it is a bacteria or fungus, it can appear as yellowing and rotting of the stem and blades, caused by the Xanthomonas campestris and Erwinia carotovora bacteria, or the Colletotrichum gloeosporioides fungi (Anthracnose).

:

√ Firstly, the stem becomes yellow, after that brown blisters appear, spreading fast, rotten stem.
√ The disease stains after days become dry and rotten, only the wooden core remains, decreasing the photosynthesis and growing new branch ability, affecting the fruit yield next season.

:

√ Spraying copper fungicide, mancozeb and metalaxyl fungicides at weekly intervals. If you have high rainfall and misty wet conditions, then try to apply some copper hydroxide before the wet conditions.

√ Remove and discard any diseased plants or parts of the plant (i.e. fruits, stems and flowers) promptly when any disease symptoms appear. Seal the wound with Cinnamon powder to prevent any new infection from getting into the plant.

√ Sterilization methods can include soaking in an alcohol solution, 10% bleach solution or heating the blades with a flame to kill any pathogens that may be present on the surface.

:

√ Ensure the Dragon fruit plants have enough nutrition such as magnesium, potassium and phosphorous with a little calcium.
√ Prevent sun damage by ensuring that plants and especially young plants are protected from the direct sunlight by providing a shade cloth or natural shade.

Purple blotch/ Leaf blotch/ Alternaria blight of Onion is caused by the fungus Alternaria porri.

√Symptoms:

Early symptoms include small brown elliptical spots on leaves, similar to IYSV lesions, which enlarge over time and may result in brown, necrotic streaks. Lesions will eventually turn purple as fungal spores develop. In severe cases, lesions enlarge and coalesce to blight the entire leaf. This pathogen requires wounds caused by other diseases (e.g. botrytis), thrips feeding, or hail, to enter the plant.

√Favorable conditions for disease development:

Hot and humid climate with temperature ranging from 21-30°C and high relative humidity (80-90%) favor the development of the disease

√Management:

Mancozeb @ 0.25% or chlorothalonil @ 0.2% or rovral @ 0.25% should be sprayed at fortnightly interval(7-10 days interval) commencing from one month after transplanting.The sticker triton/sandovit should be mixed in spray solution.

Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants.

Not included are ectoparasites like insects, mites, vertebrate, or other pests that affect plant health by eating plant tissues.

Plant pathology also involves the study of pathogen identification, disease etiology, disease cycles, economic impact, plant disease epidemiology, plant disease resistance, how plant diseases affect humans and animals, pathosystem genetics, and management of plant diseases.

When viruses infect a bacterium, they send their harmful DNA into it. If the bacterium survives the infection, it inserts a piece of the virus DNA in its genome, like a memory of the virus. This DNA is then used to protect the bacterium from new infections.

During Chemistry Laureate Emmanuelle Charpentier’s studies of Streptococcus pyogenes, one of the bacteria that cause the most harm to humanity, she discovered a previously unknown molecule, tracrRNA. Her work showed that tracrRNA is part of bacteria’s ancient immune system, CRISPR/Cas, that disarms viruses by cleaving their DNA.

Charpentier published her discovery in 2011. The same year, she initiated a collaboration with fellow 2020 Nobel Laureate Jennifer Doudna, an experienced biochemist with vast knowledge of RNA. Together, they succeeded in recreating the bacteria’s genetic scissors in a test tube and simplifying the scissors’ molecular components so they were easier to use.

The 2020 Nobel Prize in Chemistry has been awarded to Emmanuelle Charpentier and Jennifer A. Doudna “for the development of a method for genome editing.”

Press release: https://bit.ly/2Hzxp4h
Popular information: https://bit.ly/3cNgeHJ
Advanced information: https://bit.ly/2HwL3oE

▶️ of 🌾🌾🌾🌾

represent the most economically significant diseases in and other cereal crops worldwide, and they are widely distributed across wheat growing regions. With the capacity to form new strains of fungus, rusts can attack even previously resistant varieties.
▶️ 🌾🌾
Rust diseases possess the ability to spread and travel long distances by dispersal of windborne spores and can rapidly develop under optimal weather conditions.
▶️ of diseases

The three rust diseases affecting wheat are leaf, stem and stripe rust.
is the most common of the three diseases in the Central Great Plains.Leaf rust, also known as brown rust, is caused by the fungus Puccinia triticina. This rust disease occurs wherever wheat, barley and other cereal crops are grown. Leaf rust attacks foliage only. Leaf rust spores are spread by wind and splashing water.

, also known as black rust, is caused by the fungus Puccinia graminis f. sp. tritici. It infects wheat and other cereals

is becoming an increasingly important disease, with recent outbreaks in the Great Plains states.Stripe rust, also known as yellow rust, is caused by the fungus Puccinia striiformis f. sp. tritici. The disease primarily occurs on leaves, although glumes and awns may also be affected.

🏗
Farmers have several options to manage wheat rusts, ranging from seed treatments, variety selection, scouting, cultural practices and fungicide applications.
treatments
Using the correct fungicide seed treatment and rate is one way to provide effective and economical disease control in wheat production. Seed treatments protect seed and young plants from disease and other threats to plant health and yield. Areas commonly infested with rust also will need a foliar fungicide treatment to provide protection beyond the seedling growth stage.

selection
Where available, u