Chemical-Ecology on emsenn.net

Allelopathy

Thu, 02 Apr 2026 00:00:00 +0000

Allelopathy is the production of biochemical compounds by a plant that inhibit the germination, growth, survival, or reproduction of neighboring plants. The term was coined by Hans Molisch in 1937 and formalized as an ecological concept by Elroy Rice in his 1974 monograph Allelopathy. Allelopathic compounds — allelochemicals — are released into the environment through root exudation, leaching from leaves by rainfall, volatilization, and decomposition of plant litter.

Allelopathy differs from competition. Competition involves two organisms vying for the same resource (light, water, nutrients). Allelopathy involves one organism chemically suppressing another regardless of resource availability. A plant can be allelopathic even when resources are abundant — it is producing toxins, not just consuming resources faster.

Fungal Chemical Ecology

Fri, 06 Mar 2026 00:00:00 +0000

Fungi are chemical organisms. They lack eyes, ears, and nervous systems. They do not move through space in search of food. Instead, they sense, communicate, defend, and feed through chemistry — secreting enzymes, emitting volatile organic compounds (VOCs), detecting molecular gradients, and exchanging signaling molecules with organisms of other kingdoms. Fungal chemical ecology studies these processes, and it reveals an organism whose entire mode of being is mediated by molecular exchange.

Root Exudate

Fri, 06 Mar 2026 00:00:00 +0000

Root exudates are chemical compounds secreted by plant roots into the surrounding soil. They include sugars, amino acids, organic acids, flavonoids, strigolactones, and other signaling molecules. Plants release a significant portion of their photosynthetically fixed carbon — estimates range from 10% to 40% — through root exudation. This is not waste. Root exudates shape the soil environment, attract beneficial microorganisms, deter pathogens, and initiate the chemical dialogues through which mycorrhizal partnerships are established.