Evaluation of potential herbaceous biomass crops on marginal crop lands: 1, Agronomic potential. Final report, 1985-1989.

摘要

Management of herbaceous biomass crops must be investigated concurrently with the development of cost-effective conversion processes. Our objective was to evaluate the agronomic feasibility of several combinations of species and management systems for producing herbaceous biomass on sites ranging from good to marginal cropland. Soil organic matter and aggregate stability were not adversely affected by any of the management options. Of the perennial grasses and legumes investigated, switchgrass showed the most potential as a biomass candidate. It has minimum fertilizer inputs, is very persistent, and is effective in reducing soil erosion. Sorghum double-cropped with winter annual rye was very productive, but required more inputs than switchgrass. Interseeding sorghum into perennial grasses was not a viable option, due to its great dependence on environmental variables. Photoperiod-sensitive and hybrid sorghums able to utilize an entire growing season were very productive, with yields up to 39 Mg ha(sup (minus)1). Two harvest per season resulted in low yields, such that lodging resistance must be incorporated into desirable genotypes through breeding, instead of using multiple harvests to prevent lodging. Plant composition was greatly affected by species, with a wide range in composition across sorghum genotypes. Of all species evaluated, switchgrass and sorghum have the greatest biomass potential, and both of these species can be improved to produce higher yields of a more desirable chemical composition through plant breeding. 13 refs., 11 figs., 8 tabs.