Allelopathic evidence in exotic guava (Psidium guajava L.)

Abstract

ABSTRACT

Allellopathic potential of invasive Psidium guajava L., against selected native tree species in Kakamega Tropical Forest, Western Kenya.

“…Each category of leaves was washed separately in running water and 100 grams of whole leaves blended with 500 ml distilled water. The two different categories of leaves extracts obtained were filtered through a cotton cloth and concentrated to 20, 10 and 5% extracts as described by Chapla & Campos, (2010 (Barbosa et al, 2008). Inside the petri-dishes absorbent cotton were evenly distributed on the surface and saturated with 2ml concentration of each of the extract (20%, 10% and 5%) or distilled water (0%) as control, respectively to see the response of seeds to extracts under various concentrations.…”

“…According to the findings of Chapla & Campos (2010), P. guajava modify habitats, alter ecosystem services and functions, crowds out and replaces native species. Its ability to successfully invade various ecosystems is attributed to its capacity to germinate under various physical conditions, the dispersion of its seeds aided by avian and mammalian vectors (Chollom et al, 2012), ability to store its seeds deeper in soil and allelopathy Wang et al, 2015;Chapla and Campos, 2010). Allelopathy is defined as a phenomenon in which one plant affects another through release of chemicals into the environment (Zhao-hui et al, 2010).…”

“…Elsewhere, a number of studies have investigated allelopathic potential of P. guajava against various species, Bovey and Diaz-Colon, (1969); Brown et al, (1983); Chapla & Campos (2010). However, there exists no documented knowledge on P. guajava allelopathic potential against the native tree species in Kakamega forest despite its successful invasion and pressures on forest biodivesity.…”

Aqueous tissue extracts of Conyza canadensis inhibit the germination and shoot growth of three native herbs with no autotoxic effects

“…It is known to play an important role in affecting the community structure, including plant dominance and succession (Lambers et al, 1998). Recently, numerous studies have demonstrated the allelopathic effects of invasive plants on native species in the invaded ranges and provided compelling evidence for allelopathy as an important component of the competitive success of some invaders (Bais et al, 2003;Hierro & Gallaway, 2003;Prati & Bossdorf, 2004;Dorning & Cipollini, 2006;Cipollini et al, 2008;Inderjit et al, 2008;Thorpe et al, 2009;Chapla & Campos, 2010;Pisula & Meiners, 2010). Although the noxious C. canadensis poses a very serious threat to the diversity or abundance of native plant species and agricultural productivity in China, the mechanisms of the invasion of C. canadensis are still poorly understood.…”

Effects of exotic guava (Psidium guajavaL.) invasion on soil properties in Limpopo, South Africa

“…Guava trees are commercially grown in many countries with tropical to subtropical climates (Salazar et al, ). In countries where guava is invasive, the plant dominates pastures, abandoned fields and act as a pioneer species in recovering forests (Aide, Zimmerman, Pascarella, Rivera, & Marcano‐Vega, ; Berens, Farwig, Schaab, & Böhning‐Gaese, ; Chapla & Campos, ). Traits that make guava a successful invader include its re‐growth ability (Berens et al, ), seed dispersal by animals (mostly birds, which disperse seeds over long distances) and allelopathy (Chapla & Campos, ).…”