| Popis: |
Grain yields in maize are historically lower in those years when above average temperature and below average rainfall conditions prevail during the months of July and August. This is an implicit expression of the relative sensitivity of the reproductive process to heat and drought stress. Delay in silk emergence, pollen sterility, reduced ear receptivity, and kernel abortion have been associated with stress during this period. Breeding plants for greater environmental resiliency is possible, since tolerance to heat and drought stress are heritable traits. However, conventional breeding for stress tolerance has been difficult due to the lack of effective, easily measured selection criteria. |
