Background: Mulching and manual or mechanical hoeing are the backbone of weed control strategies in organic agriculture. So, two field experiments were established in the village of Kafer El-Khawazim, Talkha district, Dakahlia Governorate, Egypt, during the winter seasons of 2017 and 2018. The experiments were conducted to evaluate the efficiency of the safe weed control methods of mulching and manual hoeing in comparison with metribuzine herbicide on potato plants and associated weeds. Results: The results indicated that the treatment of black plastic mulch was the superior treatment in controlling broadleaved, grassy, and total weeds as compared to other treatments under study. Metribuzin herbicide came in the second rank in controlling broadleaved weeds. Concerning to grassy and total weeds, banana leaf and cheeseweed straw mulches follow the black plastic mulch ideal treatment. The results also revealed that the use of black plastic mulch and banana leaf mulch followed by cheeseweed straw mulch led to the highest significant increase in growth characteristics and tuber yield of potato plants. This in turn correlated with a significant increase in tuber contents of phosphorus, potassium, and carbohydrate percentage than unweeded control treatment. Conclusion: Black plastic mulch followed by banana leaf mulch and cheeseweed straw mulch were the ideal safe treatments in controlling total weeds. This in turn reflected on potato plants by scoring the maximum values of yield characters as compared to unweeded check.

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.

Background: Allelopathy is an alternative safe strategy for chemical herbicides in controlling weeds. So, two successive greenhouse experiments were conducted to determine the phytotoxicity of pea seed powder on two weeds chard-(broad leaf) and canary grass (grass weed)-infested wheat. Pea seed powder was added to the soil surface at successive rates 20, 40, 60, 80, and 100 g/pot. The pots were cultivated on time (at sowing application) or 1 week after the addition of the pea seed powder. Results: The results indicated that the pea seed powder at 100 g/pot controlled more than 70-80% of both weeds in comparison to the corresponding controls. On the other hand, the inhibitory effect of the pea seed powder on weeds was accompanied by increases in the growth as well as photosynthetic pigments content and consequently wheat yield especially at 80 g/pot. Conclusion: This study suggested that the pea seed powder has allelopathic and phytotoxic effects that controlled investigated weeds in wheat. Analysis of the allelopathic pea seed powder at the applied rates revealed the presence of phenolic compounds and flavonoids. Both allelopathic compounds showed high levels with increasing the pea seed powder rate. The mixing of pea seed powder with the soil surface at 80 g/pot 1 week before sowing was the most efficient treatment in controlling weeds under investigation that consequently achieved the highest wheat yield.

This study was conducted to evaluate the bioherbicidal properties of orange peelsagainst canary grass and cheeseweed mallow and the response of common bean plants.Two successive pot experiments were conducted with twelve treatments. The first fourtreatments were applied by incorporating of orange peels powder with the soil surface atsuccessive rates (10, 20, 30 and 40 g/pot) one week pre-sowing of common bean. Inthe other corresponding four treatments, the orange peels powder was incorporated withthe soil surface at the same rates but directly at the same time with sowing of commonbean seeds. Additionally, four untreated control treatments were applied for comparison.The recorded results revealed the inhibitory allelopathic effects of orange peels powderon both weeds with direct relationship between the orange peels rate and it's inhibitoryeffects. However, the pre-sowing treatments were more effective than the others whichapplied at the time of sowing. Orange peels at 40g/pot at one week pre-sowing gave thehighest inhibitory effect on both weeds. This superior treatment subsequently recordedthe highest growth parameters and yield traits of common bean. Estimated phenoliccompounds, flavonoids and essential oils in orange peels may be responsible for thisinhibitory effect.