Comparison of spike temperature before and at anthesis in wheat under drought and heat stress

This project focuses on the quantification of abiotic stress at flowering in the context of the plant physiology by determining how different wheat lines vary in their ability to control ear temperature before and during flowering

Department: Agriculture, Agriculture, Policy and Development

Supervised by: Dr Hannah Jones

The Placement Project

Canopy temperature depression in wheat is associated with crop yield in drought tolerant lines grown at high temperatures (Ayeneh et al, 2002). The same authors identified higher temperatures compared to the canopy (but lower than ambient) in the spike during grain development. This work is of particular interest for grain quality, but serious losses in yield can be associated with sterility, the absence of grain, when plants are subject to heat stress during early flower development. The most sensitive stage of development to heat stress is associated with sporogenesis which takes place during the booting growth stage. Stress results in malformation of the tapetal layer of pollen (e.g. Saini and Lalonde, 1998) but with limited damage to the stigma (Saini and Aspinall, 1982). The control of spike temperature is hypothesised to be affected by leaf conductance (Reynolds et al, 2007), increased root growth (Reynolds et al , 2007), awns (Evans et al, 1972) and the mobilization of sugar reserves (Wardlaw & Willenbrink, 2000). However, little consideration has be given to the changes in spike temperature during booting (when the spike is enclosed in the flag leaf) and diurnal changes in plant temperature regulation during pollen release and stigma activity at the precise time of flowering.

Tasks

Assessments: 1) Booting temperature recorded by replicated sets of thermistors inserted into booting ears and recorded by a Delta-T data logger. 2)Thermal imagery carried out using a Flir thermal imaging camera 3) Flowering synchrony will be recorded by using a method developed by Lukac and Jones (unpublished to date) developed in project BB/ H0121756/1 4) Rooting depth carried out by using replicated soil cores of established UK commercial lines at the University of Readings Crops Research Unit 5) Leaf and spike conductance It is estimated that the student will spend 90% of time across these tasks with a further 10% devoted to data analysis

Skills, knowledge and experience required

An understanding of crop physiology (desirable) An interest in climate change and the interaction with crop production (essential) Experience of field agronomy in terms of root sampling, growth stage assessment, and flowering phenology (essential) A basic understanding of statistical techniques (essential)

Skills which will be developed during the placement

Experimental techniques relating to thermal imagery of plants and specifically at pre-anthesis and anthesis. An understanding and use of thermistors for flower temperature analysis Root assessments and analyses Team work in a research context The opportunity to work alongside and compliment the research in the project BBSRC Research Grant AwardBB/H012176/1 'Genetic diversity, and yield stability for increased resilience against climate change in the UK'

Place of Work

Plant Environment Laboratory and the Crops Research Unit

Hours of Work

7 hours/day 5 days/week

Approximate Start and End Dates (not fixed)

Unknown - Monday 01 August 2011

How to Apply

Cover letter and CV