Study Of Experiment Under Regulated Deficit Irrigation For Peanut In Shenyang Area

Regulated deficit irrigation(RDI)as a new techniques have made great achievements which have decisive roles in solving agricultural water shortage,and our goal of high crop yields has gradually shifted to multiple goals such as water saving and production increase.As an important oil crop and economic crop in Liao Ning Province,peanuts are often constrained by seasonal drought.An irrigation method suitable for the area is proposed,which can not only improve the water use efficiency of peanuts in the area,but also contribute to the sustainable development of water resources.Therefore,the experiment uses black peanut named"Moxiang"as the test material,combined with RDI.Explore the experiment for flowering stage,podding stage and mature stage and different water deficit conditions(mild water control,moderate water control,severe water control,corresponding soil water contents are 60%~65%,55%~60%and 50%~55%of field capacity,respectively)was conducted to investigate the effects of RDI on the growth of root and shoot,the distribution of dry matter,the root-shoot ratio,the photosynthetic characteristics,nitrogen distribution,yield and quality,and water use efficiency(WUE)of peanut.Provide theoretical basis for the implementation of RDI in Shenyang.The main results showed follows:(1)RDI did not change the growth trend,but significantly inhibited the growth of plant height and leaf area of peanut.Different RDI treatments reduced peanut plant height by3.92%~26.75%and reduced peanut leaf area by 2.44%~26.75%.Plant growth dwarfed,and the more pronounced the inhibitory phenomenon was with increasing degree of deficit.(2)The photosynthetic performance decreased with the increase of water deficit for peanut leaves in the flowering stage and podding stage.The flowering moderate water deficit(55%~60%?_f)treatment and the podding mild water deficit(60%~65%?_f)treatment the photosynthetic performance after re-hydration could be recovered to the CK(80%~90%?_f),or even more than the CK.The average daily net photosynthetic rate of the flowering moderate water deficit(55%~60%?_f)increased by 9.73±1.15%,which produced a compensatory effect and enhanced dry matter accumulation capacity.The mature stage of peanut is yellow due to aging of the leaves,and the sensitivity to water becomes poor,so that the net photosynthetic rate is not affected by the regulation of water,and the transpiration rate of the leaves be reduced,and the water requirement of the crop be significantly reduced.(3)RDI promotes downward growth of roots,and effect of RDI on peanut root-shoot ratio growth stage:flowering stage>podding stage>mature stage.The stronger root system promoted the absorption of water and nutrients.During the end of growth stage,both flowering moderatewaterdeficit(55%~60%?_f)treatment and podding mild water deficit(60%~65%?_f)treatment maintained a large root-shoot ratio and had a good competitive advantage.The ability to transfer dry matter to pods was than CK higher 23.99±3.49%and14.05±3.01%,laying a good foundation for increasing production.(4)RDI on peanut at any stage inhibited the accumulation of nitrogen in the aerial parts of peanut,reduced the accumulation of nitrogen unrelated of yield,and promoted root nitrogen accumulation.After flowering moderate water deficit(55%~60%?_f)treatment and podding mild water deficit(60%~65%?_f)treatment re-hydration,the advantages of nitrogen accumulation in the early roots are highlighted.At the end of growth period,the nitrogen accumulation in pods and the proportion of nitrogen in pods accounted for increased by37.53%,17.62%,and 11.15%,13.85%respectively,compared with CK,and promote the transfer of nitrogen into the pod.(5)RDI at any period has an effect on both yield and quality.A certain range of RDI can stable production and even increased production,and different RDI treatments also have different effects on peanut fat,protein,and O/L value.The flowering moderate water deficit(55%~60%?_f)treatment promoted fat content and increased O/L value,and increased production by 10.06±5.73%.The podding mild water deficit(60%~65%?_f)treatment had the highest overall quality and increased yield by 11.44±9.25%.The mature moderate deficit(55%~60%?_f)treatment stabilizes yield while the fat content and O/L value perform well.(6)In any stage of peanut,water requirement is reduced with the deepening degree of RDI.The flowering moderate water deficit(55%~60%?_f)treatment and podding mild water deficit(60%~65%?_f)treatment water saving 19.71%and 9.87%,WUE increased 25.31±9.55%and 23.6±13.48%.The mature moderate deficit(55%~60%?_f)treatment showed significant water-saving potential.At the same time of stable production,water saving was 17.44%and water use efficiency was increased by 16.82±0.04%.Therefore,the flowering moderate water deficit(55%~60%?_f)treatment,the podding mild water deficit(60%~65%?_f)treatment and mature moderate deficit(55%~60%?_f)treatment are the best level of RDI in water saving,yield increase and quality in Shenyang area.