Effects of Intact Glucosinolates and Products Produced from Glucosinolates in Myrosinase-Catalyzed Hydrolysis on the Potato Cyst Nematode (Globodera rostochiensis Cv. Woll)

Abstract

The potato cyst nematode (Globodera rostochiensis cv. Woll) is responsible for large yield losses in the potato crop, and opportunities for reducing the attack of these plant nematode species are, therefore, important. This study has been devoted to the testing of the in vitro effects on the potato cyst nematode of eight glucosinolates [prop-2-enyl-, but-3-enyl-, (R)-4-methylsulfinylbut-3-enyl-, benzyl-, phenethyl-, 4-hydroxybenzyl-, (2S)-2-hydroxybut-3-enyl-, and (2R)-2-hydroxy-2-phenylethylglucosinolate] as well as the effects of the products of this myrosinase-catalyzed hydrolysis. The glucosinolates were used at three concentrations, 0.05, 0.3, and 1.0 mg/mL, in the presence or absence of the enzyme myrosinase. The effects of the compounds on the mortality were monitored every 8 h for a 72 h period. No effects were found for any of the intact glucosinolates. However, when active myrosinase was included with 1 mg/mL phenethylglucosinolate at pH 6.5, 100% mortality was observed within just 16 h. A similar effect was achieved at the same concentration of benzyl- and prop-2-enylglucosinolates in the myrosinase-containing solutions, although longer exposures were required (24 and 40 h, respectively). The main aglucone products released from the glucosinolates with pronounced effects on the nematodes were shown to be the corresponding isothiocyanates. The results suggest that mixtures of these specific glucosinolates and active myrosinase or autolysis of plant materials containing these enzymes and glucosinolates might be used to control the potato cyst nematode in the soil.

Development of an Insect Herbivore and its Pupal Parasitoid Reflect Differences in Direct Plant Defense

“…Pieris rapae is a specialist herbivore that feeds exclusively on plants producing glucosinolates Renwick and Lopez 1999). Glucosinolates and their breakdown products act as feeding deterrents or exhibit detrimental effects on the growth and development of herbivores, pathogens, and nematodes (Potter et al 1999;Li et al 2000;Buskov et al 2002). On the other hand, they are also known to act as oviposition and feeding stimulants for specialist herbivores such as Pieris rapae (van Loon and Schoonhoven 1999;Renwick and Lopez 1999).…”

Micellar electrokinetic capillary chromatography—Synchronous monitoring of substrate and products in the myrosinase catalysed hydrolysis of glucosinolates

“…Other glucosinolate and isothiocyanate derived products, especially sulphoraphane from glucoraphanin and its dithiocarbamates, and the degradation compounds of the indol-3-ylmethylglucosinolates have been reported to have antioxidant and anticarcinogenic properties [6,[19][20][21]. Isothiocyanates have also been found to be fungicidal [22,23], nematocidal [24] and bactericidal [25]. The great variety of physiological effects of the different glucosinolate derived compounds calls for further attention, especially with respect to the factors controlling glucosinolate hydrolysis and the conditions under which the different transformation products are produced.…”

Development of Mamestra brassicae and its solitary endoparasitoid Microplitis mediator on two populations of the invasive weed Bunias orientalis

“…As with many other species in the large family Brassicaceae, B. orientalis produces inducible glycoside toxins known as glucosinolates (GS). GS and their breakdown products are known to negatively affect the development of insect herbivores, pathogens, and nematodes (Potter et al 1999;Li et al 2000;Buskov et al 2002). Levels of allelochemicals often increase in response to herbivory, with potentially negative consequences for consecutive attackers (Karban and Baldwin 1997;Agrawal 1999).…”