Effect Of Wide And Narrow Row Configuration On Lodging Resistance And Yield In Maize

The increasing of maize yield should focus on the increasing of per unit area yield.The main measure to improve yield is increase the planting density.But with the increased of planting density,competitions heavy among plants,the middle and lower canopy become worse,the stalk become thinner,reduce the stalk strength of basal internode,which lead to lodging of the maize.Lodging of maize can result in the decreased of yield in high plant densities and also increased the difficult of mechanized harvest.This study elaborated in 8.25×104 plants hm-2(suitable density)and 11.25×104 plants hm-2(high density)planting density conditions,use the KX3564,ZD909 and XY41 as materials,set 60+60cm row spacing(CK),70+50 cm,80+40 cm,90+30 cm configurations four treatments,to discuss the effects of row spacing on canopy light distribution and lodging resistance in maize.In the plant density of 8.25×104 plants hm-2,the canopy light interception of 70+50cm and 80+40cm increased significantly Compare to the traditional 60 cm row spacing,this mainly because of the canopy light interception increased of the wide row light interception of H1-H3 layer especially the 80+40cm increased by.27.5%.In the high plant density,there is no obvious different between the wide narrow spacing and CK in total canopy light interception,but the distribution of light interception in wide and narrow rows were different.The wide-narrow row treatment should raise the light interception in H1-H3 layer.The canopy LAI was significantly increased in 70+50cm and 80+40cm treatment at the appropriate density.The canopy LAI of H1-H3 layer was significantly increased in 80+40cm treatment at the high density.In the suitable plant density,Plant height was decreased in 70+50cm and 80+40cm treatments compared to 60 cm row spacing,and increased in the 90+30cm treatment.In the high plant density,the coefficient of ear position and center of gravity height coefficient under narrow-wide row treatments were reduced..Basal internode length was decreased in wide-narrow row spacing compared to CK in both suitable and high plant density;Basal internode cross sectional area presents various changes among the cultivars,80+40cm treatment has increased observably basal internode cross sectional in high plant density.The DWUL of the basal internode in wide-narrow spacing were higher than CK in suitable plant density,and significantly higher than CK in the high plant density.In 8.25×104 plants hm-2 density,dry weight of stem under 70+50cm and 80+40cm treatments were significantly higher than 60 cm row spacing.Compared with CK,KX3564 and ZD909 under 70+50cm treatment increased by 7.1% and 16.3% respectively;In the high plant density,dry weight of per plant under narrow-wide row treatment was heavier than CK significantly.dry weight of stem of 80+40cm treatment increased observably compared with CK.KX3564,ZD 909 and XY 41 under 70+50cm treatment increased by 9.6%,8.2% and 20.3% respectively compared to CK.In suitable plant density,the RPS and BS of the 3rd internode were increased in the 70+50cm and 80+40cm treatment.The poor density-tolerance cultivar XY41's RPS was increased mostly in wide-narrow row spacing compared toCK.The RPS of the 3rd internode were significantly increased in the wide-narrow row spacing compared with the CK.The lodging rate was decreased in the 70+50cm and 80+40cm treatment under both suitable and high plant density.For example,the lodging rate in the 70+50cm and 80+40cm treatment of XY41 decreased 4.1% and 5.7% respectively.The XY41 was the highest among the 3 cultivars,the average lodging rate were 9.8% and 22.3% in suitable and high plant density.KX35647 and ZD 909 lodging rate below 5%.Harvest yield under 70+50cm and 80+40cm treatments higher than CK in both suitable and high plant density,KX3564 increased 3.1% and 2.4% respectively;the yield was decreased in 90+30cm,KX3564 decreased 18.3%.In the high plant density,the yield of KX3564 and ZD909 were significantly increased 3.6% and 12.2% in 80+40cm treatment.Therefore,it is concluded that compared to the traditional 60 cm row spacing,in suitable plant density the 70+50cm treatment is reasonable treatment to increase the lodging resistance improved the lower canopy light conditions;and in high plant density plant density the 80+40cm treatment is reasonable treatment to increase the lodging resistance,improved the lower canopy light conditions so that increased the yield.