Secondary metabolites of the leaf surface affected by sulphur fertilisation and perceived by the cabbage root fly

Abstract

Surrogate leaves treated with methanolic leaf surface extracts of Brassica napus L. (cv Express) plants that received three different sulphur fertilisation treatments showed even more marked differences by the oviposition choice of Delia radicum L. than the potted plants. This confirms that the oviposition preference of D. radicum is mediated by chemical compounds on the leaf surface and that the quality of host-plants in terms of their nutrition status can be perceived by the female insect.The oviposition data were positively correlated with the content of fractionated surface extracts containing either CIF ("cabbage identification factor"; 1,2-dehydro-3-thia-4,10,10b-triaza-cyclopenta[.a.]fluorine-1-carboxylic acid) or glucosinolates. Electrophysiological recordings from the tarsal chemoreceptor sensilla C 5 and D 3,4 showed that receptor neurons react to glucosinolate-and CIF-fractions. We found that the chemosensory activity of specific glucosinolate-and CIF-receptor neurons corresponded with the respective behavioural activity in the oviposition choice assays. The responses of D. radicum to glucosinolates in the electrophysiological recordings studies corresponded to the observed oviposition preference on plants or artificial leaves characterised with an higher amount of glucosinolates on leave surfaces. The presented data suggested that CIF and glucosinolates are involved in host-plant preference of D. radicum and are perceived by tarsal chemoreceptors.

Cell- and tissue-specific localization and regulation of the epithiospecifier protein in Arabidopsis thaliana

“…In addition to S-cells, Koroleva et al (2000) also identified the epidermal layer as a sulfur rich tissue, but did not determine whether this tissue is also a site of glucosinolate accumulation. Some studies have suggested an epidermal location for glucosinolates (Griffiths et al 2001;Marazzi et al 2004), but more studies are needed to substantiate these observations (Mü ller and Riederer 2005).…”

Phytochemicals of Brassicaceae in plant protection and human health – Influences of climate, environment and agronomic practice

“…Nutrient supply may also influence oviposition or feeding preference of pest insects specializing on the Brassicaceae. This is most likely due to changes in glucosinolate levels and has been observed for P. xylostella (Marazzi et al, 2004a;Staley et al, 2010), D. radicum (Marazzi et al, 2004b) and B. brassicae (Yusuf and Collins, 1998). …”

Sulphur Deficiency Causes a Reduction in Antimicrobial Potential and Leads to Increased Disease Susceptibility of Oilseed Rape

“…The same plants and extracts used in this investigation were also exposed to two different insects attacking oilseed rape, the diamond back moth and the cabbage root fly. Both insects prefer for oviposition or feeding S‐fertilized plants and extracts or fractions containing GSL or other S‐containing secondary metabolites (Marazzi et al., 2004a,b; Marazzi and Städler, 2004). It seems that these herbivores are less affected by the defence mechanisms of S‐fertilized plants and have developed detoxification mechanisms against the S‐containing secondary metabolites.…”