Impact of invasive Lantana camara on maize and cassava growth in East Usambara, Tanzania

Abstract

The impacts of invasive alien plant species on native plants are generally well documented, but little is known about the mechanisms underlying their impacts on crop growth. A better understanding of immediate as well as legacy effects and of direct and indirect impacts of invasive alien plant species is essential for an improved management of invaded cropland. We investigated how Lantana camara impacts the growth of two subsistence crops (maize and cassava) through competition for resources, allelopathy and the indirect plant–plant interactions. We carried out two pot experiments using soils from invaded abandoned, invaded cultivated and non‐invaded cultivated crop fields. In the first experiment maize and cassava were grown alone or together with L. camara and half of the pots were treated with activated carbon to suppress allelochemicals. The effect of the soil microbial community on L. camara—crop interactions was assessed in a second experiment using autoclaved soil with 5% of soil from the three soil types. We found that L. camara reduced the growth of maize by 29%, but cassava was not affected. We did not find evidence of allelopathic effects of L. camara. Inoculation of autoclaved soil with microorganisms from all soil types increased biomass of cassava and reduced the growth of maize. Because L. camara only caused impacts when growing simultaneously with maize, the results suggest that removal of L. camara will immediately mitigate its negative impacts on maize.

Investigating the phenology and interactions of competitive plant species co-occurring with invasive Lantana camara in Indian Himalayan Region

“…summarizes the life history traits of the studied species. Few studies focus on the phenological interactions between natives and invasives in the same environmental conditions 74 . Phenological duration is a crucial factor in decoding the timing of individual species and gives us insight on the timing for introducing native species in the field 24 .…”

The Combination of <i>Achnatherum inebrians</i> Extracts and Soil Microorganisms Inhibited Seed Germination and Seedling Growth in <i>Elymus nutans</i>

“…A variety of compounds are involved in the process of allelopathy, which is often affected by numerous factors [15,16]. Many studies have shown that soil microorganisms alter the activity of allelochemicals in plants, and they can also alter the competitiveness of invasive plants in populations and communities [17][18][19][20]. Existing studies have focused on the degradation of toxic compounds into toxic allelochemicals by free-living microbial communities in the soil [19][20][21], the enhancement of plant tolerance to allelochemicals [22,23], and the expansion of the impact of allelochemicals by soil microorganisms through transfer networks in the soil [24].…”