Is China able to maintain fast growth after three decades? This paper tries to answer this question by: 1) arguing that factors contributed to sustained long-run growth at supply side; 2) focusing on contributions of demographic dividend especially that of rural-urban migration; and 3) analyzing rural demographic change with information collected through village-wide household survey. Policy alternatives to realize remaining potential demographic dividend are proposed based on the analysis of changing rural demographic structure.

Drought is a major constraint in maize production worldwide. We studied quantitative trait loci (QTL) underlying droughttolerance for maize plants grown in two different environments. Traits investigated included ASI, plant height, grain yield,ear height, and ear setting. A genetic linkage map was constructed with 120 simple sequence repeat (SSR) markers basedon an F2 population derived from a cross between D5 (resistant parent) and 7924 (susceptible parent). Correlation andheritability were calculated. QTLs of these traits were identified by composite interval mapping combined with a linkagemap covering 1 790.3 cM. The markers were arranged in ten linkage groups. QTL mapping was made of the mean traitperformance of the 180 F2:3 population. The results showed five, five, six, four, and five QTLs for ASI, plant height, grainyield, ear height, and ear setting under full irrigation condition, respectively, and four, seven, six, four, and four QTLs forASI, plant height, grain yield, ear height, and ear setting under severe late stress conditions, respectively. Especially thefour QTLs detected for five traits in 2008 and 2009. The universal QTLs information generated in this study will aid inundertaking an integrated breeding strategy for further genetic studies in drought tolerance improvement in maize.