Two years of selecting for drought and low-N tolerance in two populations of maize and two hybrid groups (early and intermediate in maturity)

摘要

Maize is the most important food crop in Tanzania accounting for about 30% of the total food production during the last four years (Fews Net, 2003). The two priority stresses that impede maize production, food security, and economic growth in the southern Africa are drought and low soil fertility (Banziger et al., 2003). Tanzanian maize is not an exception to the cited two stresses (Mduruma, 2003). Due to the importance of the two stresses, drought and low soil fertility breeding for maize tolerant to the stresses is inevitable. Selection for drought tolerance in tropical maize populations has shown progress (Edmeades et al., 1999; Chapman et al., 1999). Recently in Tanzania, Malawi, Zimbabwe, and South Africa two maize open pollinated varieties (OPVs) tolerant to low nitrogen (low-N) and drought have been released (Mduruma, 2003). In breeding for drought and low-N tolerant maize, the Tanzanian national research team is working in very close collaboration with the Southern African Drought and Low-NSoil Fertility project (SADLF) and with other NARS. This paper focuses mainly on two seasons of work done in Tanzania in selecting for drought and low-N tolerant maize from two populations and two hybrid groups of different maturity (early and intermediate).