Seedling survival of abiotic stress: Sorghum and pearl millet uri icon

abstract

  • This paper reviews the responses o f sorghum and pearl millet seedlings to abioticstress and considers the implications for crop production, particularly with respect tothe arid and semi-arid tropics. The growing season in much o f this area is characterizedby high temperatures, high evaporative demand, unreliable and irregular rainfall, andsoils o f poor structure, low fertility, and low water-holding capacity.. Poor seedbedpreparation and inadequate sowing methods can increase the likelihood o f abioticstresses developing. Such conditions result in reduced seedling growth rates/ injury, andultimately mortality during the germination and seedling emergence stages. The widerange o f causes o f stand failure means there is no single solution. For a given targetenvironment it is necessary to define the reasons for a stand establishment problem andto understand the requirements o f the farmer. Genetic variation for seedling stresstolerance, however, has been shown to exist in both sorghum andpearl millet. Screeningtechniques have been developed and used in population improvement programs and inidentification o f molecular markers linked to the thermotolerance trait. Potential thusexists fo r the genetic improvement o f these crops for survival o f abiotic stresses tocomplement solutions brought about by changes in agronomic practice

publication date

  • 1996