Suppressive ability of selected fodder plants on the growth of Parthenium hysterophorus

Abstract

Summary Parthenium hysterophorus is an invasive weed in Australian rangelands. It displaces valuable fodder plants and causes significant production losses within the cattle industry. Glasshouse screening trials were used to test 20 selected fodder species (test species) for their suppressive ability against P. hysterophorus growth. The trials used two planting densities (four or six plants per pot) and five planting frequencies. Each density by planting frequency was replicated three times. The dry shoot biomass of the test species was used to calculate a suppression index, in order to rank the relative suppressive abilities of the test plants. Setaria incrassata, Panicum maxicum and Cenchrus ciliaris were ranked as strongly suppressive, while Astrebla squarrosa, Bothriochloa pertusa, Themeda triandra, Astrebla elymoides, Bothriochloa decipens, Eulalia aurea and Lablab purpureus were moderately suppressive. The other test species had only poor suppressive abilities. A second glasshouse trial assessed the growth characteristics of the test plants at 13, 27 or 40 days after transplantation (DAT). Test species that strongly suppressed the growth of Parthenium hysterophorus had several attributes that included the ability to attain a greater height, the rapid production of tillers or a branched canopy and an extensive leaf area and root system; these growth attributes were present as early as 13 DAT. The present glasshouse screening approach identified several fodder species for further testing in field trials, and because the attributes that allow the test species to suppress Parthenium hysterophorus are present at the earliest stages of the plant’s life cycle, a rapid screening method is proposed that assesses these attributes at 27 DAT.

Rising CO2 can alter fodder–weed interactions and suppression of Parthenium hysterophorus

“…hysterophorus was individually assessed using dry shoot biomass production and a suppression index (SI) value that was calculated from their shoot dry biomass by the reciprocal yield model of Spitters (). This model assumes that a plant's shoot biomass response can be fitted to a rectangular hyperbola and the competitive interactions between the two species can be calculated (Khan et al ., ). The shoot dry biomass of the test species and P .…”

“…High‐quality (>90% viable) seed of four fodder species (hereafter referred to as test species; Table ), known to be suppressive to the growth of P . hysterophorus (Khan et al ., ) were obtained from Australian‐certified seed suppliers. The P .…”

“…Seeds of the selected test species and P . hysterophorus were separately sown into trays containing a moistened University of California potting mix (Khan et al ., ) and germinated in a glasshouse. Six‐day‐old uniform sized seedlings were then transplanted into 40 pots (9 L, 25 cm diameter) each containing a natural black cracking clay soil ( c .…”

“…One additional non‐chemical management approach is the use of suppressive fodder species that limit the growth and spread of P . hysterophorus (Khan et al ., , ). This approach can be effective, environmental friendly and has shown strong synergy with biological control efforts (Shabbir et al ., ).…”

MANAGEMENT OF PARTHENIUM WEED USING METABOLITES OF Alternaria japonica

“…(Naseer-ud-Din et al, 2011), and cropping methods, e.g., hand pulling, mulching, mowing, burning and growing some competitive crops etc. (Khan et al, 2013). Shortcomings regarding chemical herbicides and increased demand of organic farming have shifted scientists' attention towards environmentally-safe weed management methods (Akbar and Javaid, 2013).…”