Research About Moisture Conservation Border Irrigation Of Winter Wheat

Straw-mulching was combined with border irrigation, they were researched to provide the basis of using the cultivation technology of moisture conservation border irrigation of winter wheat. During October of 2006 and June of 2007, this research was conducted in wuxing village of Shaanxi Yangling. In the research, there were 3 different kinds of straw length, which respectively was 2cm, 20cm and 50cm; 3 different kinds of the mulching quantity, which respectively was 300kg/667m2, 600kg/667m2, and 900kg/667m2.Then, they were combined to 9 different treatments, the treatment of"no straw-mulching"was used as CK. In the research, the straw was put over the soil before winter wheat germinating, then the soil water content was regularly measured, and this job was added pre- and post- border irrigation, the water flow developing condition was measured when irrigating"winter water"; when winter wheat returned green, the soil temperature, the tiller number and plant length were measured; after harvested, the wheat yield was measured. With the comprehensive analysise, the proper combination of straw mulchig was chose and cultivation technology was put. The results were as follows:(1) Moisture conservation border irrigation influenced obviously the development of water flow.Straw-mulching blocked obviously the water flow development when border irrigation, the flow speed was decreased obviously, which was lower than CK in different degree.The blocking effect of 300kg/667m2 was the most, then was 900kg/667m2, 600kg/667m2 was the least at the straw-mulching quantity level; which of 2cm was the most, then was 50cm, 20cm was the least at the straw length level. With the comprehensive analysise, the blocking influence of the combination of 20cm and 600kg/667m2 was the most, the combination of 2cm and 300kg/667m2 was the least.(2) Moisture conversation border irrigation had the obvious effect on conserving the moisture and adjusting the temperature in the soil.Straw-mulching could increase obviously the soil water content in 0-50cm soil layer of winter wheat, eapecially in 0-10cm soil layer. After straw-mulching (before irrigation), the mulching quantity was proportional to moisture conservation effect when the straw length was 2cm; when the length was 20cm, mulching quantity was 900kg/667m2, its moisture conservation effect is the best, then was 300kg/667m2 and 600kg/667m2; when the length is 50cm, mulching quantity was 600kg/667m2, its moisture conservation effect is the best, then was 900kg/667m2, 300kg/667m2 was the least. After 48 hours of irrigation, in the 0-10cm soil layer, its water content was larger than that of the field plot, the water content of different straw-mulching treatments was larger than CK. Irrigation could keep the water content at higher level after straw-mulching, after a long time of irrigation, it was higher than CK, so the effect of moisture conservation was obvious.Border irrigation of straw-mulching had obvious effect in adjusting the soil temperature, which could increase temperature when the soil temperature of 0-15cm soil layer was low during returning-green stage of winter wheat, decrease temperature when the soil temperature was high,decrease the change rate of soil temperature and make the soil temperature stable relatively.(3) It was found out the growth and development of winter wheat under the condition of moisture conservation border irrigation.It was the time that straw had been mulched after winter wheat being sowed, it could promote seed germination, make seedling emergence early 1-2d and make the emergence unifiorm. After entering wheat turning green stage, in some degree, straw-mulching could increase the tiller number. Compared with CK, the differences were not remarkable on the tiller number, plant height. The yield of the combination of 20cm and 600kg/667m2 was higher remarkably than CK, while else treatments of moisture conversation border irrigation were not remarkable differences. Between the treatments of moisture conversation border irrigation, the yield of the combination of 20cm and 600kg/667m2was higher remarkably than the combination of 50cm and 300kg/667m2, the two treatments had no remarkable difference comparing with others.(4) It was determined preliminarily that the suitable technology of moisture conversation border irrigation for the local winter wheat.Comprehensive consideration of water-saving and yield, the suitable combination of straw-mulching was the combination of 20cm and 600kg/667m2 in winter wheat in Yangling, Shaanxi.Combined with others'research, it was concluded that some technologies need been matched. The length of border was less than 50m and the width was in 2-3m, appropriate unit width flux was in 6～8L/(m·s); straw-mulching should be done after sowing but not germinating, you could use mechanical to increase efficience; each irrigation time and the harvesting time should be delayed than common, so that to prolong the development period to promote seed full and increase the yield of winter wheat.