|Module Title||PLANT INTERACTIONS WITH PESTS AND PATHOGENS|
|Co-ordinator||Dr Luis Mur|
|Other staff||Dr Gareth Griffith, Dr Ian Scott|
|Course delivery||Lecture||30 Hours|
|Seminar||1 Hours 1 x 1 hours|
|Assessment||Exam||3 Hours One 3-hour theory paper||80%|
|Practical exercise||Continuous assessment of practicals||20%|
|Resit assessment||3 Hours One 3-hour theory paper (plus resubmission of failed coursework or an alternative)||80%|
Aims and objectives
The course will be designed to provide a multidisciplinary introduction to plant pathology. Due stress will be paid both to the mechanisms underlying pathogenic attack or insect grazing and on the host-response. We will concentrate on model interactions that are the object of considerable research allowing the student to use “up-to-the minute” sources of information. As such, besides a description of the interaction the module will be examining the molecular determinants underlying each interaction studied. The programme will conclude with a consideration of how this scientific knowledge is being applied to reduce crop losses.
With pathogen and insects interactions we will be examining mutually antagonistic scenarios, where in response to various methods of challenge, plant species have been developed complex counter-measures.
Due to the intrinsic variation in plant structure and biochemistry as well as the need to avoid plant anti-microbial responses, plant pathogens have evolved very different 'virulence' mechanisms allowing them to exploit a plant host. We will in turn examine fungi, bacteria and viruses as plant pathogens - in each case focusing on representative pathogens which have emerged as major research models.
Plant Responses to pathogens
Plant responses to pathogenic challenge will focus on resistance associated with the hypersensitive response (HR). Key events discussed will include, the plants anti-microbial recognition, and subsequent signaling events leading to the generation of free-radicals ('the oxidative burst'), programmed cell death leading to defence gene expression. Following the HR, plants display a systemic acquired resistance (SAR) to further infection. The exhibition of SAR has been shown to be absolutely dependent on salicylic acid (SA). The role of SA in conferring SAR, together with its modes of action and biosynthesis will be discussed.
Combating the effects of insect attack
Insect grazing obviously elicits a wound response but in addition insect anti-feedants such as hexanals and the subsequent expression of proteinase inhibitors (PI) are induced. Each will be considered and the chemical signaling pathways based on 'wound-signal' jasmonic acid will be examined in some detail. The production by the wounded plant of gaseous signals to attract insect parasitoids will also be examined.
The application of biotechnology
Many biotechnological companies have aiming to increase field-resistance to pathogens and insects using methods that will be outlined in this section of the course.
Two workshops will be run during this module where infected plants to be examined and interpreted. One will focus on fungal interactions with cereals whilst the second will focus on the
On completion of the module the student will
** Recommended Text
Gurr, S.J.. (1992) Molecular plant pathology : a practical approach. Blackwell Science.
Lucas, J.A.. (1998) plant pathology and plant pathogens. 3rd. Blackwell Science.
** Multiple Copies In Hugh Owen
Agrios, G.N.. (1997) Plant Pathoglogy. 4th. Academic Press.
Issac, S.. (1992) Fungal-plant interactions. Chapman Hall.