Effects Of Fertilizer Application On Growth And Yield Of Rice

Heilongjiang Province is the main rice cultivation area in northern China,and rice production is of great significance for ensuring national food security.In recent years,due to the unreasonable amount of fertilization in rice production,the growth and development of rice has been seriously affected,not only the effect of increasing yield is not significant,and the utilization rate of fertilizer has decreased significantly.Therefore,it is of far-reaching significance to study the rational application of fertilizer on the sustainable development of rice production.In this experiment,Songyan 16 and Longyang 16 were used as materials,and based on the amount of fertilizer commonly used by farmers,five different fertilization levels were set?90%,100%,110%,120%,130%?.Study the effect of fertilizer application on growth and development,dry matter accumulation and distribution,grain filling characteristics,and yield formation in rice.It reveals the law of rice yield formation under different fertilizer application levels,so as to determine the suitable amount of N,P and K,and provide theoretical basis and technical support for the development of reasonable fertilization and cultivation techniques for rice in Heilongjiang Province.The main conclusions of this experiment are as follows:?1?The number of tillers in rice increased with the increase of fertilizer application before the heading stage,and that of the F4 treatment was higher than that of F5 treatment after the heading stage.The maximum number of tillers of both varieties increased with the increase of the amount of fertilizer,and the rate of spike rate decreased with the increase of fertilizer application.The maximum number of tillers and the spike rate in F5 treatment differed significantly from other treatments.The average maximum tiller number of each treatment of Songjing 16 was significantly higher than that of Longyang 16,and the average spike rate was significantly lower than that of Longyang 16.?2?The plant height of rice increased with the increase of fertilizer application,and the final plant height was different between varieties and treatments.The final plant height of Songjing 16increased significantly with the increase of fertilizer application,and the final plant height of Longyan 16 had no significant difference among treatments.?3?The leaf area index of rice showed a single peak curve with the growth period and reached peak value at the heading stage.The leaf area of both varieties increased with the increase of fertilizer application before the heading stage,and that of the F4 treatment was higher than that of the F5 treatment after the heading stage.The effective leaf area index?rate?increased gradually with the increase of the fertilizer application in a certain range,and that of the F4 treatment was significantly higher than other treatments.The leaf area index and the high-efficiency leaf area index?ratio?of each treatment of Songjing 16 were significantly greater than that of Longyang 16.?4?Root length,root volume,root surface area,and root vigor of rice all showed a single-peak curve with the growth period and peaked at the heading stage.The root length and root vigor gradually increased with the increase of the amount of fertilizer application in a certain range,and decreased after reaching the maximum value under F4 treatment.Both the root volume and the root surface area increased at the tillering stage-heading stage with increase of fertilizer application.After heading stage,that of F4 treatment was higher than that of F5 treatment.The root length of each treatment was lower than that of Longyan 16,and the root volume,root surface area and root activity were higher than those of Longyang 16,indicating that the roots of Songjing16 were more robust and the root growth was more vigorous.?5?During the tillering stage-heading stages,the total dry matter accumulation and the dry matter weight of the leaves and roots of the two cultivars increased with the increase of fertilizer application;After the heading stage,these of the F4 treatment was higher than these of the F5treatment.The stem and sheath dry matter weight increased with the increase of the fertilizer application.The dry matter weight of the panicle was increased with the increase of fertilizer application during heading stage-milk maturity stage increased,F5 treatment was lower than F4treatment after the milk maturity stage.During the tillering stage–jointing stage,the growth rate of group increases with fertilizer application,and that of F5 treatment is less than that of F4treatment at other growth stages.The transfer amount,translocation rate and contribution rate of steam and sheath of two varieties decreased first and then increased with the increase of fertilizer application.F4 treatment was the lowest.The root-shoot ratio of Songjing 16 decreased with the increase of fertilizer application during the tillering stage-jointing stages,and increased with the increase of fertilizer application druing the heading stage-maturity stage.The root-shoot ratio of Longyan 16 decreased with the increase of fertilizer application at tillering stage,increased with the increase of fertilizer application at jointing stage,and increased first and then decreased with the increase of fertilizer application amount during the heading stage-maturity stage,and the maximum point is at treatment F4.?6?The average grain filling speed and the maximum grain filling rate of superior grain decrease with the increase of fertilizer application,but the tendency of inferior grain is the opposite.The average grain-filling rate and maximum grain-filling rate of Songjing 16 were varied from 0.52-0.80(mg·d^-1·grain-1)and 0.77-1.18(mg·d^-1·grain^-1),respectively,with the change of fertilizer application.The range of Longyang 16 variation was 0.57-0.69?mg·d-1·grain-1?and0.84-1.02?mg·d-1·grain-1?.The effect of fertilizer application on the filling rate of Songjing 16was greater than that of Longyang 16.The time to reach the maximum grain-filling speed for superior grain and inferior grain shows the tendency to decline first and then increase with the increase of fertilizer application.There was a difference between the varieties with strong grain minimum appearance time.The shortest time for the maximum grain filling rate of Songjing 16was 12.54 days,appeared under F3 treatment.The shortest time for Longyang 16 to reach maximum grain-filling speed was 13.15 days,which appeared under F4 treatment;the minimum value of inferior grain of both varieties appeared under F2 treatment,which was 25.17 days?Songjing 16?and 25.56 days?Longyang 16?respectively.With the increase of fertilization,the duration of grain filling of superior and inferior grains was prolonged,and there was a difference of influence on the superior and inferior grains between the varieties.?7?With the increase of fertilizer application,the number of effective panicles per area and1000-grain weight of the two varieties increased first and then decreased,and the peak value appears at treatment F4;with the increase of fertilizer application,the number of grains per panicle increased and the seed setting rate decreased.The yield of the two cultivars were shown as F4>F5>F3>F2>F1.There was no significant difference between F4 and F5,but a significant difference between F4 and other treatments.The spiked rate,leaf area index at the heading stage,and efficient leaf area ratio were relatively high under F4 treatment,which was the key feature of dry matter accumulation at maturity stage and yield significantly higher than other treatments.