| Through regulation of plant density(15000 plant/hm2和45000 plant/hm2) and nitrogen levels (0kg/hm2和300kg/hm2)on more-bearing (more tillers and more ears) forage maize, physiological characteristic and regulation approach of high quantity and high quality of more-bearing forage maize were studied, in the same time tiller-disbudding was adopted. The main results were as follows:Effect of plant density on quantity and quality of more-bearing forage maizeImproving density can improve fresh and dry matter yield of ordinary single-stalk maize ND108 remarkably, though not improve yield of more-bearing forage maize. The domino effect of single plant was very distinct, and its accumulation of dry matter was rapid. Compared to CK, KD8 and KD4 had notable yield superiority: in the density of 15000 plant/hm2, the increase production of KD8 and KD4 to CK were 74.1% and 77.2%, in the density of 45000 plant/hm2 were 39.6% and 59.4%.Forage nutritive ingredients changed differently as plant density changed between genotypes: Improving density, crude protein content of KD8 and ND108 decreased, KD4 increased; content of ether extract decreased generally; in content of crude ashes and NFE, more-bearing forage maize decreased, ND108 increased; content of crude fibrin increased with improving of plant density. The nutritive ingredients content represented difference of genotypes between varieties. It did not avail to reforming of nutritive content for more-bearing forage maize in high density.Compared to ordinary maize, more-bearing forage maize had apparent yield superiority in CP, EE and CA: in the low density, it represented remarkably, in the general density, KD8 had increase production of 44.0%, 32.6% and 72.7% in the three aspects to ND108, the whole nutritive value was superior to ND108 .Effect of nitrogen level on quantity and quality of more-bearing forage maize The nitrogen domino effect of more-bearing forage maize was higher than ordinary maize, using nitrogenous fertilizer could make economic coefficient of KD8 decrease, while ND108 increased. Increasing extent of fresh matter and dry matter of KD8 was higher than ND108 by using nitrogen, so did the grain yield. Using nitrogen reduced content of crude ashes and NFE, improved content of crude protein and ether extract and crude fiber of total KD8 and ND108. In the same time, it could reduce content of soluble carbohydrate and improve content of dissociated amino acid and lysine.Nitrogen-using domino effect on more-bearing forage maize is higher than ordinary maize: the increase production of crude protein and ether extract and crude ashes are 23.9%, 1.3% and 25.3% in KD8 than in ND108 in non-nitrogen level, while the increase production are 74.0%, 47.0% and 99.3% in nitrogen-using level. 3 Effect of tillers and tiller-disbudding on more-bearing forage maizeThe improving of whole yield of more-bearing forage maize KD8 and KD4 depended on tillers to bring into play sufficiently. In the low density, the proportion of dry matter in tillers could reach 74.6% and 72.6%, density improved, they could reach 50% or so, Nitrogen-using could raise proportion of tillers remarkably. So did the grain yield proportion.Content of crude protein, crude ashes, lysine and dissociated amino acid in tillers was higher than in caulis in all treatments, content of ether extract was different in different plant densities, nutritive matter yield in tillers occupied the most proportion in total plant, total raising value in tillers was superior to it in caulis.In treatments of plant density and nitrogen, tiller-disbudding could make more-bearing forage maize to single caulis type, which would reduce fresh and dry matter remarkably (compared to non tiller-disbudding treatment). Forage nutritive component changed: content of crude, crude ashes and crude fiber in total plant decreased, content of ether extract and NFE rose a little. Comparing totally, forage quality could not achieve reforming perfectly, the whole forage value decreased apparently.4 Influenced ph...
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