The Study Of Maize Seedling Regulated Deficit Irrigation And Water-fertilizer Coupling Technology

In order to study the effect of RDI in seedling stage and water-fertilizer coupling on maize growth. we use Zhongdan 808 and Shundan 6 as materials,through pot experiment,studied the effect of RDI in seedling stage and water-fertilizer coupling technology of maize agronomic traits, physiological and biochemical characteristics, accumulation of dry matter accumulation, nutrient and the influence of production. The main results were as follows:1. The plant height, stem diameter, leaf area of Zhongdan 808 increased under the combination of 4 leaf stage,RDI for 12 d and RDI 55% ~ 65% degree. Plant height of Shundan 6 increased under the combination of 3 leaf stage,RDI for 12 d and RDI 55% ~ 65% degree. Stem diameter of Shundan 6 increased under the combination of 5 leaf stage,RDI for 12 d and RDI 55% ~ 65% degree.Leaf area of Shundan 6 increased under the combination of 4 leaf stage,RDI for 19 d and RDI 55% ~ 65% degree.Regulated deficit irrigation(RDI) in 5 leaf stage helps promote the growth of root system. Under the condition of the RDI 40% ~ 50%, continuous RDI 19 d on Zhongdan 808, RDI 26 d on Shundan 6, helps the root-shoot ratio increased.2. The dry matter accumulation of Zhongdan 808 and Shundan 6 increased under the combination of 4 leaf stage,RDI for 12 d and RDI 55% ~ 65% degree. NPK of Zhongdan 808 and Shundan 6 has the biggest accumulation under the combination of 3 leaf stage,RDI for 12 d and RDI 55% ~ 65% degree.3.Water has a decisive effect on maize agronomic traits and leaf area in water-fertilizer coupling. In water deficit heavier processing, the combination of 40% ~ 50% soil relative water content, 300 kg/ha N application rate, 100kg/ha P application rate, 200kg/ha K application rate promoted the growth of maize plant height.Under the combination of 55% ~ 65% soil relative water content,150 kg/ha N application rate, 150kg/ha P application rate, 200kg/ha K application rate promote the increase of maize stem diameter.4.Moderate water deficit can promote increased root length and root system of the firm, and get a more reasonable distribution in the soil, but the serious deficient water results in the decrease of root activity, relatively moderate water deficit treatment root diameter increased. In the severe water deficit(relative water content of 40% ~ 50%), NPK fertilizer application of 450 kg/ha, 150 kg/ha, 300 kg/ha root system performance is good; The moderate water deficit( relative water content of 55% ~ 65%), NPK fertilizer application of 150 kg/ha, 150 kg/ha, 200 kg/ha root system is best. The two processing in root traits relating performance are better than normal water treatment.5.Proper water deficit can slow down the senescence of leaf, which makes the activity of maize leaves remain relatively long time. Different water-fertilizer coupling effect on corn SOD enzyme activity and soluble protein content is similar. SOD activity is higher under the combination of 70% ~ 80% soil relative water content, 150 kg/ha N application rate, 100kg/ha P application rate, 300kg/ha K application rate after the early stage of the re-watering. With the re-watering go on, SOD keep a high activity under the combination of 40% ~ 50% soil relative water content, 450kg/ha N application rate, 150kg/ha P application rate, 300kg/ha K application rate.6.Dry matter accumulation and NPK accumulation of maize corncob and whole plant dry matter accumulation is better under the combination of 70% ~ 80% soil relative water content, 150kg/ha N application rate, 100kg/ha P application rate, 300kg/ha K application rate. And maize ear length, ear coarse, line number, number of grains per ear were higher, bald tip lowest value, obtained the highest yield under this combination.7. In this experimental conditions, the best Zhongdan 808 and Shundan 6 RDI mode: the combination of 4 leaf stage,RDI for 12 d and RDI 55% ~ 65% degree; the best water-fertilizer coupling pattern: the soil relative water content of 70% ~ 80% under the condition of NPK fertilizer application of 150 kg/ha, 100 kg/ha, 300 kg/ha.