Study On Nutrition And Growth Characteristics Of Rice Seedlings For Machine Transplanting

With social economy development, the quantity and quality of labor for rice production declinedmarkedly in rural areas, the farm labor shortage led to a change from manual to mechanicaltransplanting. It is important for mechanical transplanting that vigorous seedling is obtained for uniformstand and better seedling establishment. The effects of different fertilizer treatments on seedling qualityand nutrient uptake were studied in this research. The fix rate of nitrogen, phosphorus and potassiumwas found for getting better seedling establishment, Followed were the main results:The experiment was conducted to study the effect of different nitrogen rate on rice seedling qualityand nitrogen uptake in greenhouse. Five nitrogen levels was set up including0,0.8,1.6,2.4and3.2gram pure nitrogen per seedling tray in this experiment. Two varieties (zhongjiazao17and zhongzao39)were seeding in two kinds of conditions including mud and matrix. The results showed that,progressively higher rates of ammonium sulfate caused a gradual increase in shoot growth, but the rootgrowth decreased when pure nitrogen increase1.6to3.2gram per tray, and seedling rate decreasedgradually. N absorption characteristics under different N levels shows that with the increase of nitrogenfertilizer, percentage nitrogen content increases and when nitrogen level increases to a certain extent,nitrogen accumulation no longer increases. Plant height, shoot and root dry weight and nitrogenaccumulation in matrix are better than that in the mud seedling. So the matrix method is more suitablefor machine transplanting.In order to investigate the difference of seedlings growth characteristics and uptake characteristicsof N, P and K, four PK levels were used in this experiment, which are F1(P0g and K0g), F2(P0g andK1.8g), F3(phosphorus pentoxide1.5g and potassium oxide0g) and F4(P1.5g and K1.8g). Twovarieties (zhongjiazao17and zhongzao39) were seeding in two kinds of conditions including mud andmatrix. The results indicated that P and K fertilizer could promote shoot and root growth of seedlingsunder the same nitrogen level, and it could increase root: shoot ratio. N and P could promote rice rootgrowth in the process of raising seedling.The experiment was conducted to study the effect of different nitrogen rate on rice seedling qualityand nitrogen uptake in greenhouse. Five nitrogen levels was set up including0,0.8,1.6,2.4and3.2gram nitrogen per seedling tray in this experiment. Two single cropping rice varieties (yongyou12andxinliangyou6) were seeding in two kinds of conditions including mud and matrix. The results showedthat plant height, shoot and root dry weight increased with the increase of nitrogen levels. Whennitrogen level reaches a certain level, it will reduce the growth rate, seedling survival rate and root dryweight and it is not conducive to the improvement of the packing of seedling. The results indicates thatN accumulation and N absorption in each tray increased with N fertilizer level increases. There was nosignificant difference between two raising rice seedling methods.In order to investigate the effects of PK level on seedling growth in single cropping rice, four PKlevels were used in this experiment, which are F1(P0g and K0g,), F2(P0g and K1.8g), F3(P1.5g and K0g) and F4(P1.5g and K1.8g). Two varieties (yongyou12and xinliangyou6) were seeding intwo kinds of conditions including mud and matrix. The results showed that N and P fertilizer couldincrease seedlings dry weight, and improve seedling root growth, and application of P fertilizer wasbetter than K fertilizer in promoting rice seedling root growth. The results showed that P fertilizer couldimprove N accumulation in seedlings.