Weed Management, Folic Acid and Seaweed Extract Effects on Faba Bean Plants and Associated Weeds under Sandy Soil Conditions

Abstract

Two field experiments were conducted during the winter seasons of 2014/2015 and 2015/2016 at the agricultural experimental station of the National Research Centre, Nubaria, Egypt. Field evaluation of the efficiency of weed-control treatments (unweeded, oxadiargyl, metribuzin and two hand hoeing) and  bio-stimulants levels (folic acid at the rate of 10, 20 and 30 mg/L, and seaweed extract 100, 200 and 300 mg/L) and their interactive effects on faba bean growth, yield, yield attributes and chemical composition of seeds. Two hand hoeing achieved the highest weed depression expressed in the lowest dry matter of broadleaved, narrow-leaved and total weeds. Also, two hand hoeing was the most superior treatment in increasing plant height, shoot dry weight, leaf area index and SPAD value at 60 and 90 days from sowing as well as yield, yield attributes and chemical composition of faba bean seeds followed by that of oxadiargyl and metribuzin treatments. Folic acid at the rate of 30 mg L^-1 or seaweed extract at the rate of 300 mg L ^-1 enhanced growth, yield and chemical composition of faba bean seeds. Two hand hoeing or oxadiargyl herbicide integrated with folic acid at the rate of 30 mg L ^-1 or seaweed extract at the rate of 300 mg L ^-1 application produced the maximum values of leaf area index, seed yield and total carbohydrate percentage. It could be concluded that two hand hoeing or herbicide oxadiargyl combined with folic acid application up to 30 mg L^-1 or seaweed extract at the rate of 300 mg L ^-1 could effectively improve growth and productivity of faba bean under sandy soil conditions.