biomass accumulation among the experiments (Table 1).Consequently, the potential for seed production was vastly
different among the experiments and offered a good resource to test the potential stability in HI increase over a wide
range of conditions. The nutritional contents of wheat seeds in different treatments were given in Table 1. The contents of
rough fat, hemicellulose and ash in every treatment were relevantly closed, all of them were at the range of the nutrients of wheat seeds from field. Nitrogen, protein, fat and ash enhanced at low light intensity. Most of the variation in individual yield (grain mass) was due to plant size. Within a population, plant size is usually the best predictor of reproductive output. The relationship between total biomass and harvestable yield is very close. It was learned that spring wheat has higher HI under high water conditions but lower HI under a very dry condition (Li et al., 2002). From the ecological view,
the differences are reflected in the range of individual size under the two conditions. HI is the primary result of biomass
production and allometric growth, but not genetically determined in a direct way. The reason why this study described the stability in those important aspects of wheat biomass production, yield variability is because HI differences remain a fertile area for future research on yield assessment in BLSS. Although (Austin, 1980) it showed that the maximum biologically achievable HI is 0.60, no significant correlations were observed between HI and grain yield in this study. As a consequence, it seems that even although further enhancement of HI in BLSS is possible, it is most likely to be of only moderate magnitude. It was found that there was no significant difference between the CK (852 g/m2) and I(842 g/m2) treatments on yields per square, but the yield of II (734 g/m2) and III (721 g/m2) treatments were both lower (Fig 5B), which implies that low light intensity of early phase had no