Constant Isothiocyanate-Release Potentials across Biofumigant Seeding Rates

Abstract

Biofumigation is an integrated pest-management method involving the mulching of a glucosinolate-containing cover crop into a field in order to generate toxic isothiocyanates (ITCs), which are effective soil-borne-pest-control compounds. Variation in biofumigation efficacy demonstrates a need to better understand the factors affecting pest-control outcomes and develop best practices for choosing biofumigants, growth conditions, and mulching methods that allow the greatest potential isothiocyanate release. We measured the glucosinolate concentrations of six different commercial varieties of three biofumigant plant species: Brassica juncea (ISCI99, Vitasso, and Scala) Raphanus sativus (Diablo and Bento), and Sinapis alba (Ida Gold). The plants were grown in the range of commercially appropriate seeding rates and sampled at three growth stages (early development, mature, and 50% flowering). Within biofumigant species, the highest ITC-release potentials were achieved with B. juncea cv. ISCI99 and R. sativus cv. Bento. The highest ITC-release potential occurred at the 50% flowering growth stage across the species. The seeding rate had a minor impact on the ITC-release potential of R. sativus but had no significant effects on the ITC-release potentials of the B. juncea or S. alba cultivars.

Allyl Isothiocyanate in the Volatiles of Brassica juncea Inhibits the Growth of Root Rot Pathogens of Panax notoginseng by Inducing the Accumulation of ROS

“…However, it takes a long time to enable successful replanting if the rotation crops are not carefully selected . Many studies have found that some suitable rotation plants can alleviate root rot by directly inhibiting pathogen growth or enhancing the resistance of host plants by phytochemicals from root exudates or residue degradation. , Isothiocyanates (ITCs), the hydrolysis product of glucosinolates in Brassica plants, are considered to be good materials for alleviating soil-borne diseases. , For example, Brassica napus rotated with tobacco suppressed tobacco black shank caused by Phytophthora parasitica; the volatile ITCs could significantly inhibit the growth of root rot pathogens, such as Aphanomyces euteiches, Colletotrichum coccodes, Rhizoctonia solani, Helminthosporium solani. , Rotating Brassica with medicinal herbs or fumigating the diseased soil with ITCs may be an environmentally friendly method to alleviate root rot disease.…”

“…9,10 Isothiocyanates (ITCs), the hydrolysis product of glucosinolates in Brassica plants, are considered to be good materials for alleviating soil-borne diseases. 11,12 For example, Brassica napus rotated with tobacco suppressed tobacco black shank caused by Phytophthora parasitica; 12 the volatile ITCs could significantly inhibit the growth of root rot pathogens, such as Aphanomyces euteiches, Colletotrichum coccodes, Rhizoctonia solani, Helminthosporium solani. 13,14 Rotating Brassica with medicinal herbs or fumigating the diseased soil with ITCs may be an environmentally friendly method to alleviate root rot disease.…”

Interactions between Brassica Biofumigants and Soil Microbiota: Causes and Impacts

“…The concentration and type of GSLs varied with different plant species and crop stages. 19,130 In many studies, 117,131 the flowering stage showed the highest concentration in different biofumigant crops. 130 Furthermore, in some Brassica plants, roots have a higher concentration of GSLs than other plant parts, and they subsequently have comparatively high antimicrobial activity.…”

Effect of Biofumigation on Population Densities of Pratylenchus spp. and Verticillium spp. and Potato Yield in Eastern Canada

“…For the biofumigation treatment, the first crop of mustard was seeded on 16 June 2017 and 24 June 2019 at a seeding rate of 11.2 kg ha −1 according to seed company recommendation. The mustard plants were mowed and then immediately incorporated into the soil with disking on 20 July 2017 and 31 July 2019 at full flowering (i.e., approximately 50% flowers in main raceme open, older petals falling) for greatest biofumigation potential (Doheny-Adams et al, 2018 ; Saskatchewan mustard development commission., 2021 ). The second crop of mustard was seeded on 3 August 2017 and 6 August 2019 and mowed and immediately incorporated into the soil on 20 September 2017 and 14 September 2019 for additional biomass and biofumigation enhancement.…”