Endocidal Regulation of Secondary Metabolites in the Producing Organisms

Abstract

Secondary metabolites are defined as organic compounds that are not directly involved in the normal growth, development, and reproduction of an organism. They are widely believed to be responsible for interactions between the producing organism and its environment, with the producer avoiding their toxicities. In our experiments, however, none of the randomly selected 44 species representing different groups of plants and insects can avoid autotoxicity by its endogenous metabolites once made available. We coined the term endocides (endogenous biocides) to describe such metabolites that can poison or inhibit the parent via induced biosynthesis or external applications. Dosage-dependent endocides can selectively induce morphological mutations in the parent organism (e.g., shrubbiness/dwarfism, pleiocotyly, abnormal leaf morphogenesis, disturbed phyllotaxis, fasciated stems, and variegation in plants), inhibit its growth, development, and reproduction and cause death than non-closely related species. The propagule, as well as the organism itself contains or produces adequate endocides to kill itself.

Natural Sources and Bioactivities of 2,4-Di-Tert-Butylphenol and Its Analogs

“…However, the available data could not explain why an organism produces such toxic 2,4-DTBP. The endocide theory hypothesizes that an organism is more sensitive to its own endogenous metabolites than external molecules and thus an endocidal compound commonly occurring in different species has a broad spectrum of toxicity or low selective activity [135]. 2,4-DTBP provides a good example.…”

Endocide-Induced Abnormal Growth Forms of Invasive Giant Salvinia (Salvinia molesta)

“…In S. molesta , the abnormal forms A-C are the result of endocide-induced autotoxicity. Previously we reported that similar small-leaf mutations caused by autotoxicity in flowering plants such as Camptotheca Decaisne and Chinese tallow ( Triadica sebifera (L.) Small) (Euphorbiaceae) 26 , 39 . Small leaf cultivars were developed from C. lowreyana by extended seed soaking in water while small leaves developed following the treatment of glyphosates or decapitation pruning in T. sebifera 26 .…”

“…Since 1930, it has gradually become one of the most widespread and environmentally, economically, and socially destructive invasive species 2 , 3 . Research efforts have been dedicated to S. molesta , particularly in elucidate botany 1 , 4 – 11 , growth and reproduction 12 – 19 , ecology and invasion 7 , 17 , 20 – 24 , chemistry 3 , 25 – 27 , and control 20 – 22 , 26 , 28 – 32 . Biological, mechanical, and chemical control measures have been developed for this noxious species yet achieving full control remains a challenge.…”

Phytochemical screening and allelopathic evaluation of aqueous and methanolic leaf extracts of Populus nigra L.

“…Allelopathy is an important biological phenomenon which is directed by the releases of biological molecules from different plant parts in the form of rootexudates, leachates from above ground parts, volatilization or decomposed residues to interact with other plants, microbes and other organisms for either beneficial or negative association [1,2]. The process is intricate in nature which may be due to the interaction of various groups of chemical compounds like alkaloids, flavonoids, phenolics, glycosides, lactones, quinines, volatile terpenes, organic acids compounds and other secondary metabolites (allelochemicals) -which are produced during secondary metabolic pathways and apparently have no active role in growth and development of plants but are concerned with defense and interaction with other organisms [3,4]. Usually, the allelopathic effect of one plant on the other is perceived to be due to the synergetic or antagonistic effects of different compounds in order to make the environment conducive for allelopathic plants [5].…”