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Two pot experiments were carried out during two successive winter seasons of (2016/2017) and (2017/2018) at the green house of National Research Centre (NRC), Giza, Egypt. The experiments were conducted to compare the allelopathic effect of Beta vulgaris (shoot and root aqueous extracts at 3%, 6%, 9%) to chemical herbicides (Topik and Basagran) at recommended doses (140 g fed-1 and 1 L fed-1, respectively) in controlling weeds (Phalaris minor and Malva parviflora) associated with Lupinus albus plants. Results showed that all applied aqueous extracts caused reduction in two weeds biomass under investigation. Meanwhile, root aqueous extract was more effective than shoot aqueous extract in controlling weeds. It is worthy to mention that phenolic compounds and flavonoids in B. vulgaris root aqueous extract were higher than that in B. vulgaris shoot aqueous extract. In addition, all applied aqueous extracts increased growth, yield and yield components of L. albus plant. The inhibitory effect of B. vulgaris aqueous extract on weeds or its stimulatory effect on L. albus plants increased by increasing the extracts concentration. The two applied herbicides gave complete eradication of both weeds depending on selectivity of each herbicide followed by root aqueous extract of B. vulgaris at 9%; this in turn reflected on L. albus plants by scoring highest results as compared to unweeded treatment. [ABSTRACT FROM AUTHOR]

Allelopathy is a complex phenomenon which depends on allelochemical concentrations. So, two pot experiments were carried out to investigate the allelopathic effect of alcoholic fresh shoot extract of Eruca sativa (foliar spray) and E. sativa shoot powder (mixed with soil) on Pisum sativum plants and two associated weeds, Phalaris minor and Beta vulgaris. The experiments were conducted in the greenhouse of the National Research Centre, Giza, Egypt during two successive winter seasons (2016-2017 and 2017-2018). Ten treatments were applied in this study. Four treatments were applied before sowing, that E. sativa shoot powder was mixed with the soil at rates of 15, 30, 45 and 60 g · pot-1. The other four treatments of E. sativa alcoholic fresh shoot extract were sprayed twice on both plants and weeds at 5, 10, 15 and 20% (w/v) concentrations. Additionally, two untreated treatments, healthy (P. sativum only) and unweeded (untreated infested P. sativum plants with weeds) were applied for comparison. The results indicated that both alcoholic extracts and powder reduced growth of both weeds. Moreover, there was a direct relationship between concentration and weed reduction. Eruca sativa alcoholic extracts increased yield parameters of P. sativum plants. The maximum yield attributes were recorded by spraying of E. sativa alcoholic extract at 20%. On the other hand, it was clearly noticed that the high powder rates affected negatively P. sativum yield parameters. But the lowest powder rate (15 g · pot-1) stimulated P. sativum yield parameters as compared to unweeded treatment. Chemical analysis of E. sativa shoot powder ensured that the abundant amount of glucosinolates (9.6 μmol · g-1) and phenolic compounds (46.5 mg · g-1) may be responsible for its allelopathic effect. In conclusion, spraying of alcoholic fresh shoot extract of E. sativa at 20% (w/v) and mixing E. sativa shoot powder at 15 g · pot-1can be applied as natural bioherbicides for controlling weeds. [ABSTRACT FROM AUTHOR]

Background: Brassica species have been established to have very high concentrations of glucosinolates, flavonols, and other secondary metabolites that achieved good results in weed management strategy. So, this study highlights how to investigate the allelopathic potential of Eruca sativa fresh shoot aqueous extract as a natural bioherbicide to control Phalaris minor and Beta vulgaris weeds beside its effect on Pisum sativum growth as well as yield traits. Two pot experiments were conducted in the greenhouse of the National Research Centre, Dokki, Giza, Egypt, in the two successive winter seasons of (2016–2017, 2017–2018). Treatments were applied by spraying E. sativa fresh shoot aqueous extract once at 14 days after sowing and twice at 14 and 21 days after sowing at rates of 20, 40, 60, and 80% w/v. Results: E. sativa fresh shoot aqueous extract at 80% achieved the maximum inhibition effect on the growth of both weeds. This in turn was reflected on P. sativum plant and gave the observable highest growth and yield parameters. Chemical analysis of E. sativa shoot powder approved the presence glucosinolates (9.6 μmol/g) and phenolic compounds (46.5 mg/g) which may be responsible for the allelopathic effect. Conclusion: Spraying of aqueous fresh shoot extract of E. sativa at 80% (w/v) can be applied as natural selective bioherbicide in controlling the two annual grassy and broad-leaved weeds associated with P. sativum plants. [ABSTRACT FROM AUTHOR]