The Effect Of Slow-controlled Release Fertilizers On Yield And Agronomic Traits Of Summer Maize

The mechanism of increasing yield of slow-controlled release fertilizers?SRFs?for maize was studied in Wugong,north of Central Shaanxi Plain from May to October,2018.During the test,it was divided into four parts.The first part A was slow-controlled release fertilizers,its total pure nutrients was 300kg/hm²?Its available nutrient N-P₂O₅-K2O was210-45-45kg/hm²?;And it was blended into three treatments with different ratios of N-P₂O₅-K₂O by the traditional quick-acting fertilizer urea?N 46%?,diammonium phosphate?N 15%-P₂O₅ 42%?and potassium sulfate?K₂O 51%?.So the second part B was called control fertilization?CK?,the total amount of applied pure nutrients was 300 kg/hm²?Its available nutrient N-P₂O₅-K₂O was 210-45-45kg/hm²?;The third part C was habitual fertilization 1,and the total amount of applied pure nutrients was 390 kg/hm²?Its available nutrient N-P₂O₅-K₂O was 300-45-45kg/hm²?;The forth part D was habitual fertilization2,and the total amount of applied pure nutrients was 322.5 kg/hm²?Its available nutrient N-P₂O₅-K₂O was 300-22.5-0kg/hm²?.The maize was arranged in random blocks and repeated 6 times.The results of the experimental research are summarized as follows:1.SRFs had a significant effect on increasing yield compared with traditional fertilizer corn with the same amount of available nutrients.SRFs?A?had obvious yield increasing effect;its yield was 9882kg/hm²,compared to controlled fertilization B,the yield of controlled fertilization B was 9213 kg/hm².The maize's yield which was used SRFs increased by 2.0%and 4.7%,which compared to treatment?C?whose yield was 9685kg/hm² and treatment?D?whose yield was 9435.5 kg/hm².At the same time,slow and SRFs not only could improve some economic properties of maize effectively,but also increase the number of grains per ear and 100-grain weight effectively.The bald tip of corn ear which was used SRFs was 0.8 centimeter long.Its length was 0.9 centimeter shorter than the bald tip of fruit ear of fertilization?B?.And the bald tip of fruit ear of fertilization B was 1.7centimeters long;The number of grains in each row was 33.5,and the weight of 100-grain was 33 grams in the test A?which was used SRFs?,which increased by 1.6 grains and 13.5g respectively.However the number of grains in each row was 31.9,and the weight of100-grain was 31.65 grams in the control fertilizer?B?;The number of grains per row and100-grain weight in SRFs?A?increased by 1.1 grains,1.8 grains,0.36g and 0.93g respectively,compared with treatments?C?and?D?.2.SRFs could improve the leaf area index of corn significantly,and delay leaf senescence,improve the photosynthetic potential and chlorophyll content of maize significantly,and maintain a higher leaf area duration during filling period.The leaf area index of slow controlled release fertilizer?A?treatment was 4.34,4.22 and 3.05 at silking stage,milk stage and mature stage,which increased by 5.85%,16.57%and 12.55%,respectively,compared with the control fertilization?B?.The leaf area index,of mature period increased by 5.54%and 6.27 which compared with C and D.The total photosynthetic potential of SARs?A?was 270.98,which increased by 7.54%compared with the control fertilizer?B?.The photosynthetic potential of SARs?A?from silking to milking and from milking to ripening were 107 and 83.27 respectively,and increased by 10.88%and 12.48%respectively.The photosynthetic potential of SARs?A?for grain production accounted was70.2%,and increased by 2.5%compared with control fertilizer.And increased by 2.7%and2.6%compared with reatment C and D respectively.The SPAD value of slow and controlled release fertilizer?A?treatment at milk stage was 62.7,which was 6.5%higher than that of the control.And increased by 6.3%and 9.4%,compared with treatments C and D.The SPAD value of mature period increased by 54.7%,5.7%and 29.8%respectively compared with the three treatments of B,C and D.3.SARs could promote the growth of maize roots,increase the number of heel strips per plant significantly and accelerate the accumulation of dry matter in grains.The root number of SARs?A?increased rapidly after jointing.The root number of SARs?A?in big bell mouth stage,silking stage and mature stage were 57.9,63.2 and 66.4 respectively,which increased by 13.3%,11.9%and 16.9%compared with control fertilization?B?in the same period.The root number of SARs?A?increased by 4.5%,8.2%and 13.5%compared with treatment C.The root number of SARs?A?increased by 8%,10.5%and 15.9%respectively compared with treatment D.During the whole filling period,the dry matter of maize in SARs?A?accumulated faster,and the 100-grain weight of maize increased by 2.2%-4.8%from 15days after pollination to maturity compared with that of maize in control fertilizer?B?;and the weight of 100 grains increased by 0.9%².3%and 1.5%³.3%,respectively compared with treatment Cand D.The dry matter accumulation?100-grain weight?of SARs?A?in0-31 days before grouting was 25.63g,which was 0.71g,0.38g and 0.64 g higher than that of B,C and D treatments respectively.And the weight of 100 grains increased by 0.84g,0.39g and 0.44g in the 31⁴7 days after grouting compared with the three treatments of B,C and D.4.The economic benefit of slow-controlled release fertilizer is obviously higher than that of traditional chemical fertilizer corn.Compared with the conventional fertilizer B,C and D,the economic benefits of slow-release fertilizer?A?treatment were increased by13.5%,10%and 9.7%respectively.The input-output ratio of slow-release fertilizer was 1:6.99,and the input-output ratios of the other three treatments were 1:4.77,1:4.3 and 1:5.06,respectively.5.Conclusion:5.1 SARs had obvious effect of increasing production.The maize yield which was used SARs increased by 7.3%,compared with the available fertilizer?control?with the same amount of available nutrients.And the maize yield which was used SARs increased by 2.0%and 4.7%,compared with conventional fertilization C and D with more available nutrients.5.2 SARs could reduce the loss of fertilizer efficiency effectively,save fertilizer and keep fertilizer.5.3 SARs could significantly improve corn leaf area index and delay leaf senescence,and the photosynthetic potential and chlorophyll content of corn are obviously improved at the middle and late period of corn growth.The duration of green leaf area was kept high during the grouting period,and SARs could promote the growth of root system,improve the economic characteristics of ear effectively,increase the weight of 100 grains and the number of grains per ear,and finally increase the yield of maize.5.4 Slow-controlled release fertilizers can increase yield and benefit compared with traditional quick-acting fertilizers.