Factors affecting frost damage to wheat in Western Australia

It may at first seem strange that precious research funds are being channelled into a project concerned with frost damage in a country where high temperatures and moisture stress limit the growth of plants for a large portion of the year. But cereal crops are only grown in the temperate zones of the continent during winter and spring when they may be exposed to low diurnal temperatures. In many areas cold damage is irregular and rare,however it limits yields not only by causing actual damage but also by restricting the most effective period for flowering. For muck of the Australian wheat crop excessive risk of frost damage sets the earliest date for flowering and the beginning of grain filling at a time when other conditions are at their most favourable for carbohydrate assimilation. The latest date for flowering is determined by high temperatures and low water availability towards the end of the grain filling phase. An optimum flowering time and maximised yield in the long term are achieved when a compromise between the effects of frost and drought is reached