Plant diseases track planetary gravity, says study
how about a link between plant diseases and interplanetary gravity? Researchers from Penn State University and the University of Virginia, tried to explain just that. Their study shows that the spread of plant diseases can be described by equations that model interplanetary gravity. It was published online in The American Naturalist's website.
Tracking a fungal disease spread by bees and moths in the course of pollinating and feeding on nectar from white campion flowers, researchers have concluded that insects are more likely to move shorter distances between better quality plants. "Interestingly then, the probability of disease being passed between two plants goes up if they are closer to each other. This parallels the stronger gravity between closer and larger planets,' said the authors. Most plant pathogens are transmitted by arthropod vectors whose movement between individual hosts is influenced by foraging behaviour."Insect foraging depends on both the quality of hosts and the distances between hosts. Given the spatial distribution of host plants and individual variation in quality, vector foraging patterns may therefore produce predictable variation in exposure to pathogens,' they added.
Explaining the mechanism, the co-authors said, "Insects tend to transmit diseases in the course of feeding on plants, and their movement between plants is influenced by plant quality (quality and quantity of food the plant provides for the insect) and the distance between plants, or, how far they'll have to travel to get to the next meal.' According to them the knowledge of insect behaviour can lead to a better prediction of where disease will spread. But they also added that such patterns are not limited to diseases of plants or diseases carried by insects only. The researchers have previously shown that similar patterns describe the spread of measles in cities because people tend to travel more between large towns or only short distances.