description
- Severe weather can cause crops to become uprooted or their stems to break, a process called lodging. This means that the crops do not grow to their full potential which reduces the quantity of seed they produce (the yield). Lodging makes crops more susceptible to infection by fungi which can produce toxic chemicals known as mycotoxins which render the grain unusable. These impacts of lodging substantially reduce the value of a crop and there can be additional costs of drying the grain. By taking appropriate action (e.g. choice of crop variety and how it is managed) it is possible for farmers to reduce the likelihood of lodging. Over the past 20 years great advances have been made with improving understanding and control of lodging in cereal crops (e.g. wheat) grown in the UK through the development of realistic models of the lodging process which have been used to develop practical husbandry strategies enabling farmers to reduce lodging. Understanding of the lodging process in maize and rice is less advanced than in UK cereal crops and lodging in maize and rice crops commonly reduces yields by up to 40% representing a major constraint for crop productivity, particularly for low/middle income countries. This project will use world leading UK expertise in lodging science to develop understanding and mitigation strategies that enable maize and rice producing regions to minimise lodging. This strategy will increase the resilience of maize and rice production systems to climate variability and produce safer food by reducing mycotoxin development in lodged crops. Both rice and maize have very different morphologies from the crops that have already been modelled for the lodging process. New lodging models will be developed that take account of the large hanging panicles, high tiller numbers and shallow rooting system of rice; and the thick hollow stem, braced root system, much taller stature and large leaves of maize. Additionally characteristics of the climate (wind and rainfall) of different regions will be built into the models. These lodging models will be developed and tested using wind tunnel tests on pot grown plants and field tests. A framework for identifying regions and fields with the highest risk of lodging will be produced which will account for how landscape features affect wind flow over crops and how Earth Observation (EO) technologies (e.g. vegetation index maps from satellites) may be used to identify the fields with crops that are most at risk to lodging. Frequently it is found that crops with large canopies (vegetation indices) have a greater risk to lodging later in the growing season. The understanding about wind flow, EO technologies and the new lodging models will be combined into a single integrated system. This system will then be used to help farmers to mitigate lodging risk; 1) strategically by planting lodging resistant varieties in regions with a high risk of lodging and 2) tactically by reducing nitrogen fertiliser and prioritising harvest for fields (and even part fields) which are shown to have developed a high risk of lodging during the growing season. The lodging models will be used to understand how variation in crop parameters caused by changes in crop husbandry, environmental parameters (wind, rainfall and soil type) and predictions of climate change will affect lodging risk in maize and rice within different global regions. This work will identify which crop parameters have the greatest influence on lodging risk and therefore should be targeted by plant breeders.