Effect of thinning in different years on yield and canopy structure in Erianthus populations
2018
Kanai, I. (Tokyo University of Agriculture (Japan). Graduate School of Agriculture) | Morita, S.
Erianthus, a perennial Csub(4) grass, has been the focus of attention as cellulosic raw material for bioethanol, because it shows high yield performance and high tolerance to environmental stresses. We examined canopy structure of one- and two-year Erianthus populations in the previous report. The result of our investigation showed that two-year population had much higher yield comparing with one-year population. At the same time analysis on the canopy structure of two-year population suggested light condition in the canopy might be worse, though this has not yet been verified. In this study, we examined effect of thinning from 1 m x 1 m to 2 m x 1 m in different years. A-population was thinned after the two-year harvesting, B-population thinned after the one-year harvesting, respectively. As a result, biomass production in the subsequent year was larger by decrease in the planting density by thinning, possibly because of improving light conditions in the canopy. Although the yield in the second year of B-population is less than that of A-population, total yield during the first three years of B-population is much more than that of A-population. Based on the analysis of yield of both populations, yield should depend on the number of tiller buds formed in the previous year and growth period of tillers. In conclusion it is considered better to control planting density to improve the light condition in the canopy to lead to better growth and development of tillers through increasing matter production to get greater total yield during growth period, where the thinning time should be determined depending on growth condition.
اظهر المزيد [+] اقل [-]