The Lodging Resistance And Yield Of Rice As Affected By Applying Si, Ca, N, Organic Manure, And Film-mulched And Dry-farming

The effects of applying Si,Ca,N,organic fertilizers,and film-mulched and dry-farming on lodging resistance and yield of 6 rice varieties at the later growth stages were studied by field plot experiments and determination at room during two years.The main results were as follow:1.Applying Si fertilizer could apparently improve the lodging resistance of mid-season super hybrid rice.The medium Si fertilizer dosage treatment(applying Na₂SiO₃·5H₂O 150 kg/hm²) did the best among various treatments,and it made the lodging index of rice lower 6.14%～27.43%compared to CK treatment.For 2 varieties, the lodging index of Liangyou 293 treated with Si fertilizer was lower 41.64%～53.76%than Zhunliangyou 527 at later growth stages.The latter appeared lodging at wax maturity stage,but the former one had not appeared lodging until ripening stage.Their lodging index at ripening stage increased 108.12%～158.69%than at milky stage.Applying Si fertilizer was benefitial to increasing base stem diameter,N4 stem diameter,N4 sheath thickness,N4 stalk wall thickness,N4 sheath phimosis degree,Si contents of stem,sheath,N4 stem and sheath,bleeding intensity of lower internode,single area of N4 big vascular bundle and total area of N4 big vascular bundle of mid-season super hybrid rice.Meanwhile,applying Si fertilizer could reduce the length of first base internode,N4 stem flat rate and N4 breaking index of mid-season super hybrid rice at later growth stages.The lodging index was negatively correlated with lodging resistance per plant,base stem diameter, N4 stem unit length dry weight,single area of N4 big vascular bundle,total area of N4 big vascular bundle,N4 sheath thickness,leaf dry weight,N4 stem diameter, N4 sheath phimosis degree,bleeding intensity of lower internode,N4 section modulus,sheath dry weight,number of N4 big vascular bundle,N4 breaking resistance, stem dry weight and dry weight of single stem and sheath,and was positively correlated with panicle dry weight,N4-panicle length,N6 length,dry matter transfer rate of stem and sheath,plant height,real lodging rate,plant dry weight, N4 banging stress and N2 length at significant level of P0.05 or P0.01, respectively.The N4-panicle length had the most positive effect on lodging followed by N2 length,plant dry weight,N4 banging stress,N6 length,panicle length and base stem flat rate,while the total area of N4 big vascular bundle had the most positive effect on lodging resistance followed by lodging resistance per plant,single area of N4 big vascular bundle,N4 stem unit length dry weight, base stem diameter,N4 section modulus,number of N4 big vascular bundle,N4 sheath phimosis degree,sheath dry weight,N4 breaking resistance,dry weight of single stem and sheath,N4 stalk wall thickness,N4 stem flat rate,si content of N4 stem and sheath,and N4 plant moment.Under the experimental conditions,applying Si fertilizer could not obviously improve the theoretical yield and components of mid-season super hybrid rice, but increase its actual yield by lowering the real lodging rate and reducing the loss of yield.The main strategy of increasing grain yield was to increase 1000 grain weight and filled grain per ear.The higher the yield,the greater the risk of lodging.Lodging was the important factor that significant difference between the theoretical yield and actual yield existed.2.Applying Ca fertilizer had an apparent effect on improvement of lodging resistance of Zhunliangyou 527.Of which,the medium and high Ca fertilizer dosage treatments(applying Ca(OH)₂ 450kg～675kg/hm²) had the best effect,and its lodging index lowered 13.74%～24.26%than CK treatment.Applying Ca fertilizer had decreasing trend on lowering the lodging index of Liangyou 293 in later growth stages,even a negative effect at ripening stage.For 2 varieties,the lodging index of Liangyou 293 treated with Ca fertilizer lowered 46.07%～57.19%than Zhunliangyou 527.The latter began lodging at wax maturity stage,but the former had not begun lodging until ripening stage.Their lodging index at ripening stage increased 67.13%～110.77%than at milky stage.Applying Ca fertilizer was benefitial to increasing N5 length,base stem flat rate,N4 stalk wall thickness,N4 sheath phimosis degree,Ca contents of stem, sheath,N4 stem and sheath of mid-season super hybrid rice,and,reducing its bleeding intensity of lower internode,single area of N4 big vascular bundle, and total area of N4 big vascular bundle.The lodging index was negatively correlated with lodging resistance per plant,base stem diameter,bleeding intensity of lower internode,N4 sheath phimosis degree,N4 stem diameter,total area of N4 big vascular bundle,leaf dry weight,single area of N4 big vascular bundle,N4 breaking resistance,N4 section modulus,N4 sheath thickness,N4-panicle fresh weight,N4 stem unit length dry weight,number of N4 big vascular bundle, N4 plant moment,sheath dry weight,stem dry weight,and dry weight of single stem and sheath at significant level of P0.05 or P0.01,respectively.Also,the lodging index was positively correlated with real lodging rate,dry matter transfer rate of stem and sheath,plant height,N4-panicle length,panicle dry weight,N4 banging stress,N5 length,plant dry weight,and panicle length at significant level of P0.05 or P0.01,respectively.The N4 banging stress had the most positive effect on lodging followed by N4-panicle fresh weight,N4 length,N3 length,N5 length, N4-panicle length,N1 length,N4 breaking index,N4 stem flat rate and base stem flat rate,respectively.The N4 plant moment had the most positive effect on lodging resistance followed by N4 stem unit length dry weight,N4 section modulus,N4 breaking resistance,lodging resistance per plant,N4 sheath phimosis degree, number of N4 big vascular bundle,stem dry weight,N4 stalk wall thickness,sheath dry weight,and N4 breaking moment,respectively.Applying high dosage Ca fertilizer could improve the actual yield,theoretical yield and components of Zhunliangyou 527.Applying medium Ca fertilizer dosage could increase its yield by lowering the real lodging rate.But applying Ca fertilizer could not improve the theoretical yield and most components of Liangyou 293.The main strategy of increasing grain yield was to increase seed setting percentage and 1000 grain weight,The lodging index was positively correlated with 1000 grain weight,seed setting percentage and actual yield at significant level of P0.05 or P0.01,respectively.Also,the lodging index was negatively correlated with filled grain per ear at significant level of P0.05.3.Under 180kg/hm² equivalent to N fertilizer,applying slow-release N fertilizer could improve the lodging resistance of early-season super hybrid rice Zhuliangyou 02 apparently,The medium and high N fertilizer dosage treatments (applying 142.5kg～150kg/hm² equivalent to N) had the best effect,and its lodging index lowered 11.46%～46.51%and 14.64%～54.11%than CK treatment in 2007 and 2008, respectively.Its lodging index in 2007 was lower 69.57%～81.63%than in 2008, and its lodging index at ripening stage increased 161.12%～332.49%than at milky stage in 2007 and 2008.But it did not appear lodging. Also,applying N fertilizer could apparently increase the plant height,plant dry weight,leaf area index,content of chlorophyll,SOD activity,CAT activity, soluble sugar content and root activity of early-season super hybrid rice at later growth stages,and reduce the MDA content of its functional leaf at ripening stage. The lodging index was negatively correlated with root activity,leaf area index, content of chlorophyll and lodging resistance per plant,and positively correlated with MDA content and SOD activity at the significant level of P0.05 or P0.01, respectively.The MDA content and plant dry weight had the most positive effect on lodging,The root activity had the most positive effect on lodging resistance followed by lodging resistance per plant,content of chlorophyll and CAT activity.Compared with CK treatment,applying N fertilizer obviously increased the ear length,productive panicle,filled grain per ear and 1000 grain weight,and significantly improved yield of Zhuliangyou 02.Of which,applying 120kg～180kg/hm² equivalent to N had the best effect,The main strategy of increasing production was to increase productive panicle,ear length and filled grain per ear.The lodging index was negatively correlated with 1000 grain weight,productive panicle and actual yield significantly,respectively.4.The order of effect of applying organic ferlilizer on improving lodging resistance of late-season high-quality rice in magnitude was biogas manure＞chicken manure＞rapeseed fertilizer＞tobacco stalk fertilizer;combined application of organic and inorganic fertilizer＞single organic fertilizer＞chemical fertilizer＞no fertilization.The lodging index of Yuzhenxiang and Yuzhuxiang by applying biogas manure and chicken manure lowered 10.11%～34.16% and 17.75%～29.85%than that by applying rapeseed fertilizer and tobacco stalk fertilizer,respectively.The lodging index of Yuzhenxiang by combined application of organic and inorganic fertilizer lowered 29.78%～39.21%,40.54%～61.07%and 49.45%～74.14%than that by applying single organic fertilizer,chemical fertilizer and no fertilization,respectively.Under applying biogas manure, chicken manure,rapeseed fertilizer and tobacco stalk fertilizer,the lodging index of Yuzhuxiang at later growth stages lowered 23.73%～40.42%,13.61%～38.17%, 0.51%～41.38%and 20.41%～50.04%than that of Yuzhenxiang,respectively,and their lodging index at ripening stage increased 451.32%～836.63%than one at milky stage. Under combined application of organic and inorganic fertilizer,single organic fertilizer,single chemical fertilizer and no fertilizer,the lodging index of Yuzhenxiang at ripening stage increased 547.47%,647.86%,768.89%and 827.59%than that at milky stage,respectively.Yuzhenxiang by applying tobacco stalk fertilizer began lodging at milky stage,under other treatments,it began lodging at wax maturity stage.Under all treatments,Yuzhuxiang began lodging at wax maturity stage.There was no obvious difference between applying different kinds of organic fertilizer in the plant height of late-season high-quality rice,there was obvious difference in the plant dry weight due to different organic manure treatment. Compared with no fertilizer,combined application of organic and inorganic fertilizer,single organic fertilizer and single chemic fertilizer significantly increased the plant height and plant dry weight of Yuzhenxiang.Under applying different kinds or ratios of organic manure,the lodging index of late-season high-quality rice was negatively correlated with lodging resistance per plant at the significant level of P0.01,and positively correlated with plant dry weight and plant height at the significant level of P0.05 or P0.01,respectively. The most positive factor on lodging of all treatments was plant dry weight.The most positive factor on lodging resistance of all treatments was lodging resistance per plant.Applying chicken manure and biogas manure could obviously improved the grain yield than applying rapeseed fertilizer and tobacco stalk fertilizer.Compared with CK treatment,applying different ratios of organic manure could significantly improved the grain yield of late-season high-quality rice:the order of theoretical yield of late-season high-quality rice by different fertilizer treatments in magnitude was single chemic fertilizer＞single organic fertilizer＞combined application of organic and inorganic fertilizer,but there was no obvious difference between their actual yield.Under applying different kinds of organic fertilizer,the main strategy of increasing the theoretical yield was to increase 1000 grain weight and filled grain per ear;the lodging index was negatively correlated with actual yield,theoretical yield,1000 grain weight and filled grain per ear at the significant level of P0.05 or P0.01,respectively.Under applying different ratios of organic fertilizer, the main strategy of increasing the theoretical yield was to increase filled grain per ear,productive panicle and 1000 grain weight;the lodging index was negatively correlated with 1000 grain weight and productive panicle at the significant level of P0.05 or P0.01,respectively.The greater lodging resistance of late-season high-quality rice,the higher yield they had.There were significant differences between theoretical yield and actual yield due to different lodging resistance under all treatments.5.The order of effect of improving lodging resistance and lowering lodging index of mid-season hybrid rice 88S/1128 in magnitude was water-farming and non-film-mulched＞water-farming and film-mulched＞dry-farming and non-film-mulched＞dry-farming and film-mulched.The lodging index under water-farming significantly lowered 9.47%～24.10%than that under dry-farming, and the lodging index under non-film-mulched significantly lowered 14.68%～17.09% than that under film-mulched,respectively.Dry-farming and film-mulched were benefitial to lowering the plant height of mid-season hybrid rice,and obviously improving its plant dry weight,leaf area index,net photosynthetic rate,stomatal conductance,intercellular CO₂ concentration and transpiration rate.The lodging index was negatively correlated with plant lodging resistance,transpiration rate,intercellular CO₂ concentration and net photosynthetic rate significantly,respectively,and positively correlated with plant dry weight significantly.The plant dry weight had the most positive effect on lodging,and the plant lodging resistance had the most positive effect on lodging resistance followed by transpiration rate,intercellular CO₂ concentration,net photosynthetic rate and stomatal conductance.The order of yield of 88S/1128 treated with various cultivation practices was dry-farming and film-mulched＞water-farming and film-mulched＞dry-farming and non-film-mulched＞water-farming and non-film-mulched.Compared with non-film-mulched or water-farming,film-mulched or dry-farming obviously improved the productice panicle,filled grain per ear,seed setting percentage and 1000 grain weight.The main strategy of increasing grain yield was to increase seed setting percentage and productice panicle.The higher yield potentiality,the greater the risk of lodging was.The greater lodging resistance,the less the loss of yield was.