Studies On Cultivation Practice For High Yield And Superior Quality And On High-yielding Mechanism In Potatoes

This paper took Qing-Potato 6 as test materials , adopted quadratic current revolve combination test design methed. The physiological index Chlorophyll content, Soluble sugar content, Photosynthetic rate , Leaf area index and Tuber yield were measured on different potato procreating stages:Tuber formation , Tuber expand, Starch accumulate,Ripe stage respectively. The results showed that:1 The effect of the different fertilizing combination on chlorophyll content in potato leaves was bigger on earlier stage than later, The chlorophyll content increased with fertilizing dosage within low fertilizing dosage range, After the chlorophyll content came up to the highest point, With the fertilizing dosage increased the chlorophyll content was not increasing,Yet the chlorophyll content dropped with the density increasing constantly, accordingly the fertilizing dosage and density of optimization fertilizer and density was Urea :400 kilogram per hectare, Triple phosphate fertilizer: 243.75 kilogram per hectare, Potassium chloride :112.5 kilogram per hectare and Density: 60 thousand per hectare. The highest Chlorophyll content was 1.8 percent.2 The correlation index between the soluble sugar content in potato leaves on different stage and potato tuber yield was failure to the prominence difference.3 Within the levels range under this test design, existed the extreme prominence regress relation between the different fertilizing density combination, photosynthetic rate in potato leaves and plot tuber yield. The effect of the different fertilizing combination on photosynthetic rate in potato leaves was: Potassium fertilizer>Nitrogen fertilizer>phosphate fertilizer>density. The lower or higher fertilizing dosage of Nitrogen fertilizer, phosphate fertilizer, Potassium fertilize could depress the potato photosynthetic rate ,with the potato density increased, the photosynthetic rate would decrease gradually, even the decrease rate became much faster continuously , the effects of Nitrogen fertilizer and phosphate fertilizer, Nitrogen fertilizer and density , Potassium fertilize and density on potato photosynthetic rate was positive interaction.4 The fertilizing dosage under this test design,with the nitrogen fertilizer ,phosphate fertilizer and Potassium fertilizer increased ,the leaf area index was increasing gradually,but it did not increase the largest. The effect of density on potato leaf area index was not achieved prominence under the density plant with the test design. 5 The Nitrogen fertilizer and phosphate fertilizer,Nitrogen fertilizer and Potassium fertilizer,phosphate fertilizer and Potassium fertilizer of different Fertilizing and Density and potato plot tuber yield model all act : The plot tuber yield was higher when the high levels of two factors cooperated. When potato tuber yield achieved the highest The optimization combination was : pure Nitrogen 172.5 kilogram per hectare, P2O5: 112.1 kilogram per hectare , KCl:112.1 kilogram per hectare , Density :60 thousand per hectare ,and the potato highest theoretical yield was 41.48 tons per hectare.