Plant disease GapFill

Plants, like animals, can also suffer from  hungerinjurythirstdisease, which can be a cause of concern for gardeners and farmers. This can be as a result of a viral,  chromosomalbacterialribosomalcellular or fungal infection, or due to the action of insects. Gardeners and farmers can detect this by identifying visual changes in a plant, such as areas of decay or unusual growths called  boilsmutantslesionsbruises, and can compare the symptoms to those described or photographed in a manual. They can also send samples to a laboratory or make use of testing kits to identify the  pathogentoxincellpredator involved.

To prevent loss of  watertasteyieldcolour across a wide area, farmers use  immunologynumericaldistributionbacterial analysis, often aided by  beesdronesfertilisersdogs. Diseases spread via the wind will often affect plants in a large  circleconesquarespiral shape radiating from the first affected plant, whereas diseases as a result of insects or pathogens in the soil will affect plants in a smaller  circlecylindersquarecube.

Plants do have some natural defences against pathogens and predators. Physical defences act to prevent microorganisms from entering a plant, such as tough waxy cuticles on  flowersbranchesleavespollen and  chloroplastscell wallsmitochondriacell membranes made of cellulose. One of the best plant defence responses against pests is the use of chemicals. Some chemicals are released constantly, but this is a costly method for the plant, so many plants only release chemicals when they  are wateredare attackedreproducedry out.

Humans have made use of some of these chemicals as medicines. For example,  paracetamolpenicillinibuprofenaspirin, originally from salicylic acid produced by willow trees, is a common painkiller and can be used to treat some of the  pathogenscausessymptomspests of fever.