Table 3.
Plant-sourced bioherbicides and their impact on targeted weeds.
| Plant Source | Target Weed(s) | Effect a | Mode of Action | Commercial | Reference | |
|---|---|---|---|---|---|---|
| Allelochemicals | Canavalia ensiformis extract (50 g L−1) | Commelina benghalensis (Benghal dayflower) | **** | Causes inhibition of plant growth and development | X | [82] |
| Ipomoea grandifolia (little bell) | **** | |||||
| Cirsium setosum (HL-1 isolate) | Chenopodium album (goosefoot) | *** | Creates high levels of phytotoxins that inhibit seed germination and plant growth | X | [83] | |
| Galium aparine (cleavers) | *** | |||||
| Malva crispa (Chinese mallow | *** | |||||
| Polygonum lapathifolium (pale knotweed | *** | |||||
| Cynara cardunculus (Ethanol + Lyophilized leaf extracts) | Amaranthus retroflexus (redroot pigweed), Anagallis arvensis (scarlet pimpernel), Phalaris minor (little seed canary grass), Portulaca oleracea (little hogweed), Stellaria media (chickweed), Sylibum marianum (milk thistle), Trifolium incarnatum (crimson clover) | **** | Induces oxidative stress and disrupts physiological and biochemical functions within the plant cells. | X | [84,85] | |
| Juglans nigra (black walnut) extracts (>42.9% concentration) | Convolvulus arvensis (field bindweed) | **** | Inhibits H+-ATPase activity decreases photosynthesis and reduces root, leaf and cotyledon production | NatureCur® (USA). Limited availability. | [86] | |
| Conyza bonariensis (hairy fleabane) | **** | |||||
| Conyza canadensis (horseweed) | **** | |||||
| Echinochloa crus-galli (barnyard | **** | |||||
| Ipomoea purpurea (tall annual) | **** | |||||
| Portulaca oleraceae (common purslane) | **** | |||||
| Solanum nigrum (black nightshade) | **** | |||||
| Lantana camara cold and hot extracts | Avena fatua (common wild oats) | *** | Allelopathic compounds (aromatic) present in the plant cause the suppression of plant growth and germination | X | [81] | |
| Euphorbia helioscopia (sun spurge) | *** | |||||
| Phalaris minor (little seed canarygrass) | *** | |||||
| Rumex dentatus (toothed dock) | *** | |||||
| Ocimum basilicum extracts | Amaranthus species | *** | Inhibits germination, growth and root/shoot elongation | X | [87] | |
| Portulaca species | *** | |||||
| Sorghum bicolor (great millet) |
Amaranthus retroflexus (redroot pigweed), Ambrosia artemisiifolia (common ragweed), Cassia obtusifolia (sicklepod), Coronopus didyum (lesser swinecress), Cyperus rotundus (purple nutsedge), Phalaris minor (littleseed canary grass), Solanum nigrum (black nightshade) |
- | Inhibits photosynthetic apparatus by altering the uptake of solutes and water molecules. | X | [88] | |
| Essential Oils | Corymbia citriodora, formerly Eucalyptus citriodora (formerly, oil (0.03% concentration) | Avena fatua (common wild oat) | **** | Impacts chlorophyll and cellular membranes causing chlorophyll and cell disruption | X | [94] |
| Sinapis arvensis (charlock) | **** | |||||
| Sonchus oleraceus (common sowthistle) | **** | |||||
| Corymbia citriodora, formerly Eucalyptus citriodora oil (0.06% concentration) | Amaranthus viridis (slender amaranth) | **** | Inhibits seed germination and plant growth by affecting photosynthetic and respiratory metabolism. | X | [91] | |
| Bidens pilosa (blackjack) | **** | |||||
| Leucaena leucocephala (lead tree) | **** | |||||
| Rumex nepalensis (nepal dock) | **** | |||||
| Corymbia citriodora, formerly Eucalyptus citriodora oil (5.0 nL mL−1 concentration) |
Parthenium hysterophorus (parthenium weed) |
**** | Causes rapid electrolyte leakage, which impacts membrane integrity. | X | [98] | |
| Eucalyptus globulus oil + Syzygium aromaticcum (Clove) oil (10% concentration) | Chenopodium album (goosefoot) | *** | Causes rapid electrolyte leakage and cellular membrane disruption. | X | [95] | |
| Melilotus indicus (Indian sweet clover) | *** | |||||
| Raphanus raphanistrum (wild radish) | *** | |||||
| Sisymbrium irio (London rocket) | *** | |||||
| Lemon-scented Eucalyptus citriodora oil (0.07% concentration) | Phalaris minor (littleseed canary grass) | **** | Impacts the photosynthetic and respiratory ability of treated plants. | X | [91] | |
| Manuka oil mixture from Leptospermum scoparium (manuka tree) | Avena sterilis (sterile oat) | **** | Natural b-triketones inhibit the biosynthesis of tocochromanols and prenyl quinones. | X | [92,96] | |
| Galium aparine (clever) | **** | |||||
| Lolium rigidum (rigid ryegrass) | **** | |||||
| Pine oil (10% concentration) + sugar |
Nassella trichotoma (Serrated tussock) other herbaceous and grassy weeds |
- | Inhibits seed germination and plant growth. | Bioweed™ | [93] |
a Effect: (-) = not applicable/available, *** = 50–75%, **** = 75–100% control/plant growth reduction. X = not commercially available.