It’s March and the first flowers of the year have already started to bloom. For most, snowdrops will delight with their white down-facing bells. However, actual dig-in-the-dirt gardening is still quite a while in the future, so let’s catch up on some interesting scientific studies.

Trees. Did you know there are about 64,000 known tree species in the world? According to a study published in the Proceedings of the National Academy of Science, 9,200 unknown species are still waiting to be discovered and identified. 

The main hot spot for unknown trees? South America, according to 100 scientists from around the world who participated in the study. Tropical and sub-tropical areas around the globe, especially the Amazon basin are very species-diverse regions.

Losing animal diversity impacts plants. This study’s results were published in the January issue of Science. Different plants have differing methods for dispersing seeds. The methods that move the seeds the farthest depend on animals, either carried in their digestive systems or riding on fur or feathers. Not all animals can keep up with climate change, nor can all plants. The plants that can hitch hike the farthest away from old warming habitats have a better chance of survival than those that can’t move very far from the mother plant. 

“The researchers estimate that the bird and mammal species that have already gone extinct have reduced the capacity of plants to track climate change by 60 percent globally.” 

Boosting a plant’s immunity during heat waves. I saved the good news for last. Extended excess heat weakens a plant’s immune system, making them more susceptible to pathogen and insect damage. A study by scientists at Duke, Yale, UC Berkeley, and an Agricultural University in China, “…reverse-engineered a process to bolster plants’ defenses against pathogens and insect pests in times of heat stress, a strategy that may become vital in our warming climate.”

When a pathogen attacks, a defense hormone called salicylic acid increases which helps prevent infection. However, an increase in temperatures, even shortly, means the plant doesn’t have enough salicylic acid to fight back.

The scientists discovered a gene named CBP6og that acts like a master switch affecting other genes. Unfortunately, heat stress turns off CBP6og, causing salicylic acid production to cease. In test plants (Arabidopsis) they found a way to keep the CBP6og gene switched on. The defense hormones stayed high, providing the plants with resistance against infection.

I found these three synopses in various issues of The American Gardener Magazine published by The American Horticulture Society. 

The Extension Master Gardeners of Edgar County look forward to helping you with your landscape problems. Call the University of Illinois Extension Master Gardeners of Edgar County for gardening information at 217-465-8585 or schiver@illinois.edu.