Effects Of Density And P Fertilizer On Growing And Yielding Characters As Well As Quality Of Panicum Miliacum L.

The experiment was conducted with the random-blocks design in field. The relationship is systematically studied between different density, the way of using phosphorus fertilizer and growing, yield and quality characters of Panicum miliacum L.. The results show that during the whole growing period, the content of chlorophyll is the single-peak curve, and peak value at milk stage. Chlorophyll content reduces with the increase of the density, and leaf of low-density declines slower than that of high-density. The max effect of density on chlorophyll content is that all phosphorus fertilizer is used during the period of jointing stage to the booting stage. The leaf chlorophyll content increases with the quantity of phosphorus fertilizer in the middle and late period, which can delay the death of leaf. Leaf area of single plant reaches peak at bloom stage .The density and the phosphorus fertilizer can significantly effect on the leaf area during middle to late stage of Panicum miliacum L.. During the bloom stage to the milk stage, the leaf area of D3 is higher than that of D1. With the addition of phosphorus fertilizer, the leaf area increases in middle and late stage. The change of photosynthetic rate in the whole growing period is single-peak curve, and peak value at milk stage. With the reducing of density, the value of photosynthetic rate promotes in middle and late stage. The usage of phosphorus fertilizer can obviously improve photosynthetic rate, especially usage of phosphorus fertilizer during jointing stage to the booting stage. The change of transpiration rate show "S", reach supreme value at milk stage. At booting and milk stage, the transpiration rate increases with the increase of density. But as the increase of phosphorus fertilizer, transpiration rate decreases. Stomatal conductance of the whole growing period shows bimodal curve, and the former peak is low and the later one is high which takes place at milk stage. The same fertilizer of the two variety decline as the density reduce, the phenomenon is very much obvious in the period of heading stage and bloom stage. The jointing stage to bloom stage is the fast increasing stage of the plant height. The plant height is not increase any more after bloom stage. During jointing to booting stage the density has various effect on the plant height. Plant height of low density is higher than that of high density .The phosphorus fertilizer can lower the plant height on early stage.With the increase of density at the same time, ear grains, the number of grains, thousand grain weight, stem thick ,ear length reduce ear grain. The yield of 180,000/ hectare and 220,000 / hectare are higher 5% than that of the 260,000 / hectare. The stem diameter presents positivecorrelation with output. Yield characters and the yield are higher as increasing phosphorus fertilizer, and in can effetely higher the stem thick. The yield of increasing phosphorus fertilizer can increase yield for 1.2%-2.5%. The result shows that the key way to increase the ear grain and thousand-grain weight is to chase phosphorus fertilizer during the jointing to booting stage, with the middle density. If we want to higher the number of the grain, we should chase phosphorus fertilizer during the jointing to booting stage under middle density. The key way to make the plant stronger is to increase the stem thick, to have a strong stem thick, we should chase the fertilizer during the jointing to booting stage with the middle density.The density has little effect on the content of protein and the starch, but the content of fat is lower with the higher of the density. Increasing the phosphorus fertilizer can higher the content of the protein, and it has little relation with the way to chase the fertilizer. Although it can increase the content of fat with increase of phosphorus fertilizer, but it is not very obvious. The content of starch is lowered with the chasing of phosphorus fertilizer, and it has little difference between the two ways. The result show: the way to higher the content of protein and fat...