Study Of The Effect Of Density Regulation On Potato Tuber Size Distribution And Nutrients Accumulation

In this experiment,the effects of different density and density control methods on the agronomic traits,tuber size distribution and nutrient accumulation of potato were studied by setting different number of planting holes and different main stem number.The aim was to find the appropriate density and density control method to increase the uptake of nutrients,build healthy group structure and improve the production of tubers for meeting the different production aims.Through the two-year district trial,the main conclusions are as follows:To early maturing variety of Youjin,The plant height increased by increasing the planting density or increasing stems,the effect of the number of main stems on plant height and stem diameter was more significant than that of planting density.The planting density of 60 000holes/hm2 with 1 stems per hole have the smallest plant height(54.4 cm),tallest stem diameter(12.5 mm),The planting density of 120 000 holes/hm2 with 3 stems per hole have the tallest plant height(65.6 cm),smallest stem diameter(8.6 mm).At harvest,To per plant the tuber nitrogen,phosphorus,potassium accumulation,dry matter accumulation of potato leaf and tuber dry matter accumulation and plant dry matter accumulation were increased by the increasing in the number of seed points is 60 000 holes/hm2?90 000 holes/hm2?120 000 holes /hm2.And the 3 stems treatment was greater than 1 stem treatment.while,to the unit area,tuber nitrogen,phosphorus,potassium accumulation,leaf dry matter accumulation,tuber dry matter accumulation and plant dry matter accumulation,the number of seeding points were the same,still 3 stems greater than 1 stem treatment.When the number of main stem is the same,the increase of the number of planting points is 120 000 holes / hm2> 90 000 holes / hm2> 60000 holes / hm2.To early maturing variety of Youjin,the planting density of 120 000 holes/hm2 with 3 stems per hole and harvest at 60 d after emergence was suitable for seed potatoes production,while 60000 holes/hm2 with 3 stems per hole suitable for marketable tuber production.The yield of tubers of the grade 30-150 g is 18.2 t/hm2,accounting for 70% of total production.To late-maturing variety of Kexin 13,The plant height increased by increasing the planting density or increasing stems,the effect of the number of main stems on plant height and stem diameter was more significant than that of planting density.The planting density of 60 000holes/hm2 with 1 stems per hole have the smallest plant height(43.3 cm),tallest stem diameter(12.8 mm),The planting density of 100 000 holes/hm2 with 3 stems per hole have the tallest plant height(53.3 cm),smallest stem diameter(11.2 mm).At harvest,To per plant the tuber nitrogen,phosphorus,potassium accumulation,dry matter accumulation of potato leaf and tuber dry matter accumulation and plant dry matter accumulation were increased by the increasing in the number of seed points is 60 000 holes/hm2?80 000 holes/hm2?100 000 holes /hm2.And the 3 stems treatment was greater than 1 stem treatment.while,the unit area tuber nitrogen,phosphorus,potassium accumulation,leaf dry matter accumulation,tuber dry matter accumulation and plant dry matter accumulation,the number of seeding points were the same,still 3 stems greater than 1 stem treatment.When the number of main stem is the same,the increase of the number of planting points is 100,000 holes / hm2> 80,000 holes / hm2> 60,000 holes / hm2.To late-maturing variety of Kexin 13,the planting density of 80 000 holes/hm2 with 2 stems per hole and harvest at 80 d was suitable for seed potatoes production and 60 000 holds/hm2 with 2stems per hole suitable for marketable tuber production,The yield of tubers of the grade 30-150 g is 20.1 t/hm2,accounting for 49% of total production.