Abstract
A slow growth during the early stage in sugarcane yields low productivity in spite of its long cropping duration, though the photosynthesis ability is high. A small specific leaf area(SLA)is the main reason it takes longer for the canopy structure to complete. To investigate the enhancement of the early growth in sugarcane, six commercial varieties were grown for this experiment. Ninety-four sugarcane genetic resources were also applied in measuring the leaf characteristics. SLA sal negatively correlates with leaf thickness and leaf length per width ratio(leaf index). It is appropriate to make leaf blades short, wide, and thin to get high SLA. Dry matter per stem was obviously higher in the lesser tillering variety because the number of tillers did not affect the total dry matter production in early growth. By filling the stem numbers per area using high density planting, the rapid stem growth of the less-tillering variety enables quicker growth in the early stage in the sugarcane community. A shortening of the sugarcane growing seasons is required for an effective field usage of crop shifting. As well as the effective canopy structure for solar radiation, the morphological characteristics for rapid growth in the early stage were regarded as an important selection point in breeding.
