Potential Use of Sweet Potato (Ipomoea batatas (L.) Lam.) to Suppress Three Invasive Plant Species in Agroecosystems (Ageratum conyzoides L., Bidens pilosa L., and Galinsoga parviflora Cav.)

Shicai Shen,Yanxian Yang,Leslie A Weston,Guimei Jin,Aidong Chen,Fudou Zhang,Diyu Li,Shufang Liu,Jia Rao,Xiaocheng Zhu,David Roy Clements,Gaofeng Xu

doi:10.3390/agronomy9060318

Abstract

Sweet potato (Ipomoea batatas (L.) Lam.) is a logical candidate crop to suppress invasive plants, but additional information is needed to support its potential application as a suppressive ground cover. The current study utilized a de Wit replacement series incorporating five ratios of sweet potato grown in the field in combination with one of three invasive plants (Ageratum conyzoides L., Bidens pilosa L., and Galinsoga parviflora Cav.) in replicated 9 m2 plots. Stem length, total biomass, and leaf area were higher for monoculture-grown sweet potato than these parameters for any of the invasive plants grown in monoculture. In mixed culture, the plant height, branch, leaf, inflorescence, seed, and biomass of all invasive plants were suppressed by sweet potato. The relative yield parameter indicated that intraspecific competition was greater than interspecific competition for sweet potato, while the reverse was true for invasive species. The net photosynthetic rate was higher for sweet potato than for B. pilosa and G. parviflora but not A. conyzoides. Superoxide dismutase and peroxidase activities of each of the three invasive plants were reduced in mixture with sweet potato. Our results demonstrated that these three invasive plants were significantly suppressed by sweet potato competition due to the rapid growth and phenotypic plasticity of sweet potato.

Highlights

Biological plant invasions have commanded considerable global attention because they have resulted in serious economic damage, environmental problems, loss of biodiversity, and threatened ecosystem safety and human and animal biosecurity [1,2]
The main objective of this study was, to examine competitive and physiological interactions of sweet potato with the three invasive plant species (A. conyzoides, B. pilosa, and G. parviflora) utilizing a de Wit replacement series [34] and provide insights on how similar ecological control methods could be applied to other invasive alien species
In all three invasive plants, the main stem length was much less than the branch length, whereas the main stem length was greater than the branch length for sweet potato, in all treatments (Figure 1A–C, Table S1)

Summary

Introduction

Biological plant invasions have commanded considerable global attention because they have resulted in serious economic damage, environmental problems, loss of biodiversity, and threatened ecosystem safety and human and animal biosecurity [1,2]. Numerous methods have been developed to manage invasive plant species, but the most effective control is generally achieved using herbicides [3]. One relatively unexplored alternative is the use of other plant species that can suppress invasive plants, referred to as competitive cropping or replacement control [5,6]. The use of high-value competitive crop species (e.g., local food and/or cash crops) utilizes the competitive ability of such plants to inhibit exotic plants while simultaneously reducing invasive species damage and enhancing ecosystem health [5,6,7,8,9,10]. Compared to mechanical or chemical management, control with competitive crops can potentially be more economical, ecological, and sustainable [5]. Revegetation with high-value crops has been recognized broadly as an important means for both the long-term management of current infestations and the restoration of formerly invaded areas following successful control [11]

Objectives

Methods

Results

Discussion

Conclusion