Project description:Plant defence against insects is well known to be affected by previous exposure to cues warning of herbivory. Using Arabidopsis thaliana and the herbivore Pieris brassicae, we addressed the question whether the maintenance of the effects of the warning cue depends on its reliability. We determined the transcriptomes of Arabidopsis leaves that were treated by P. brassicae egg deposition (i) five days after oviposition, (ii) one day after removal of the eggs following the egg treatment, (iii) three days after removal of the eggs, (iv) after two days of herbivory that started one day after removal of the eggs; or that were treated by chilling (v) five days after transfer to 4°C, (vi) one day after transfering the plants to 20°C following the chilling treatment, (vii) three days after transfering the plants to 20°C, (viii) after two days of herbivory that started one day after transfering the plants to 20°C. Arabidopsis thaliana Col-0 wild type plants were grown under short day conditions (10 h/14 h light/dark) at 20°C for 7 weeks. Subsequently (i) the plants were transferred to 4°C for 5 days, or (ii) Pieris brassicae deposited ca. 40 eggs on leaf 17 where they remained for five days, or (iii) as controls plants grew untreated for five days. Next, the plants were transferred back to 20°C and the eggs were removed, respectively. Next, all plants rested for 1 day at 20°C. Next, P. brassicae larvae were allowed to feed for 2 days on leaf 17 adjacent to the former egg deposit site or at a respective leaf region of chilling-treated or untreated plants. Control plants were not exposed to larvae. From all treated and untreated plants material from a leaf region proximal to the egg deposition and/or feeding site was harvested for transcriptome analysis.
Project description:Plant defence against insects is well known to be affected by previous exposure to cues warning of herbivory. Using Arabidopsis thaliana and the herbivore Pieris brassicae, we addressed the question whether the maintenance of the effects of the warning cue depends on its reliability. We determined the transcriptomes of Arabidopsis leaves that were treated by P. brassicae egg deposition (i) five days after oviposition, (ii) one day after removal of the eggs following the egg treatment, (iii) three days after removal of the eggs, (iv) after two days of herbivory that started one day after removal of the eggs; or that were treated by chilling (v) five days after transfer to 4°C, (vi) one day after transfering the plants to 20°C following the chilling treatment, (vii) three days after transfering the plants to 20°C, (viii) after two days of herbivory that started one day after transfering the plants to 20°C.
Project description:Plants can prepare their defense of impending herbivory, when they previously perceived eggs deposited by herbivores insect which reliably indicates that larvae will soon hatch and feed on the plants. Using Arabidopsis thaliana and Pieris brassicae we addressed the question whether prior egg deposition affects transcriptional changes in feeding-damaged plants. We determined the transcriptomes of Arabidopsis leaves that (i) were for six days deposited with eggs and suffered larval feeding for two days, (ii) suffered larval feeding for two days without prior egg deposition or (iii) were left untreated.
Project description:In Arabidopsis thaliana it is known that plants that harboured eggs of the White cabbage butterfly (Pieris brassicae) before larval feeding can defend better against the herbivore stress. As Arabidopsis thaliana is an annual plant we were interested in the plant defense and possible priming reaction of the closest biannual/perennial relative Arabidopsis lyrata. The main aim of the experiment was to compare the effect induced by insect egg deposition of Pieris brassicae between A. thaliana and A. lyrata plants grown in parallel on the transcriptional level. We used a full factorial setup consisting of a) untreated control plants , b) plants which experienced eggs for 6 days without larval feeding after that period, c) plants which experienced no eggs before larval feeding for 24 hours d) plants which experienced eggs for 6 days and larval herbivory for 24 hours. This setup was conducted with 7 week old vegetative plants For all treatments leaf tissue from the leaves that experienced egg oviposition and/or larval feeding were collected.
Project description:Plants can cope with stress better if they experience a mild form of the stress before the actual \\"real\\" stress event. In Arabidopsis thaliana it is known that plants that harboured eggs of the White cabbage butterfly (Pieris brassicae) before larval feeding can defend better against the herbivore stress. The main aim of the experiment was to compare the priming effect induced by insect egg deposition of Pieris brassicae between vegetative and reproductive (first open flowers) Arabidopsis thaliana plants on the transcriptional level. We used a full factorial setup consisting of a) untreated control plants , b) plants which experienced eggs for 6 days without larval feeding after that period, c) plants which experienced no eggs before larval feeding for 24 hours d) plants which experienced eggs for 6 days and larval herbivory for 24 hours. This setup was conducted with 6 week old vegetative plants and 10 week old reproductive plants were the first flowers were open. For all treatments leaf tissue from the leaves that experienced egg oviposition and/or larval feeding were collected. From reproductive plants flower buds were collected as well.
Project description:Although a seemingly harmless developmental stage of herbivores, insect eggs trigger efficient plant defenses that include necrosis, callus formation, accumulation of ovicidal compounds and release of volatiles to attract egg predators. The large white butterfly Pieris brassicae deposits batches of 20-30 eggs onto Arabidopsis leaves, causing a large transcriptional reprograming that is drastically distinct from the expression profile triggered by larval feeding. Also, P. brassicae eggs induce localized cell death, accumulation of reactive oxygen species (ROS) and salicylic acid (SA), and expression of PTI-related genes, suggesting that egg-associated molecular patterns (EAMPs) activate a response that is similar to the response induced by microbial pathogens. We previously reported that a crude P. brassicae egg extract (EE, soluble fraction from crushed eggs) induced similar responses as oviposition, including ROS and SA accumulation, cell death and defense gene induction. In order to compare oviposition and EE treatment at the transcriptome level, we analyzed changes in transcipt abundance with P. brassicae EE or after natural oviposition. After 5 days, hundreds of genes were significantly upregulated by each treatment and their induction was highly similar between treatments. This conserved transcriptomic signature thus strongly supports our previous observations that oviposition and EE treatment trigger comparable responses in Arabidopsis.
Project description:Gene expression in Arabidopsis thaliana leaves after chilling and/or herbivory by Pieris brassicae or Mamestra brassice larvae or after mechanical wounding
Project description:Brassica nigra plants, a Brassicaceae close to Arabidopsis thaliana, was used for combined stresses experiments. In this study, we performed a whole-genome microarray analysis on five-week-old plants and compared untreated plants and plants treated different single or dual stresses: the larvae Pieris brassicae, egg extract of Pieris brassicae, the bacterial Xanthomonas campestris pv. raphani, the aphid Brevicoryne brassicae or by combined stresses eggs of P. brassicae / P. brassicae, X. campestris / P. brassicae, B. brassicae / P. brassicae.
