The Effects Of Regulated Deficit Irrigation On Water Use And Productivity Of Lycopersicon Esculentum In The Middle Reaches Of The Heihe River

Regulated deficit irrigation is that according to crop growth of different organsdifferences in demand for water, control soil moisture content, the optimal allocationof limited irrigation water, in order to achieve the purpose of water-saving increase.Heihe River Basin is one of the most poor areas of China's water resources, demandfor water resources contradiction between the economic and social development andecological protection. Improve the efficiency of agricultural water has become the keyto reconcile the various sectors of the contradictions of the water, is placed at alllevels of leadership and the majority of scientific and technological work in front of amajor issue. By water requirement of tomato, the planting structure adjustment modelsimilar areas of the northwest, to contribute to the development of conservationminded society. The middle reaches of the Heihe River in Zhangye City of Mainprocessing tomato varieties Riegel87-5in the seedling stage, flowering fruit set andfruit enlargement stage and harvest of normal irrigation (the ck, the soil water suction200KPa) mild water deficit (LD, the soil water suction400KPa) and moderate waterdeficit (MD, three levels of soil water suction800KPa), the period of water deficit andextent of processing tomato plants growth, photosynthetic characteristics, yieldformation, fruit quality and irrigation water use efficiency to achieve the followingresults:1. There is very significant difference between the seedling stage severe waterdeficit and ck; flowering fruit set LD and ck have significant difference; fruitenlargement and last stage water deficit were higher than the ck, and the significantdifference; for each period and ck, moderate water deficit are the highest plant height.Plant leaf number: seedling stage, significant differences between the ck and LD;flowering fruit set treatment, significant differences between the ck and MD; fruitenlargement and last stage are significant differences with the ck; the general trend ofleaf number of each period is LD>ck>MD. Root to shoot ratio: seedling stage,flowering fruit set, the last stage and ck: MD>ck>LD; during fruit enlargement stage, with the increase of the treatment level, root to shoot ratio decreased; at each period.different treatment level and ck are significant differences.(4) fruit set number:flowering fruit set,number of fruit set T3(LD) higher than the ck and the difference isremarkable, the ck are higher than T4(MD)and differences are very significant; fruitenlargement stage are LD>ck>MD, without a significant difference between these; thelast stage with the levels of treatment increased fruit set increasing, no significantdifference between treatments and ck.2. Determination of light response curve of the fruit enlargement stage: themaximum net photosynthetic rate (Pnmax), dark respiration rate (Rd), light saturationpoint (LSP), light compensation point (LCP) have trend as following: with the level ofwater deficit strengthen the gradual decreasing, which reflecting the impact ofmoisture on net photosynthetic rate as a photosynthetic reactants. Diurnal meancomparison, the fruit enlargement stage of LD>ck>MD, seedling stage, floweringfruit set and harvest of ck> LD, MD, moderate water deficit (MD) Daylightco-product of the cumulative volume is less than the ck.3. Yield compared T3>T4>T7>ck>T2>T8>T5>T1>T6, processing had nosignificant effect on yield. Lycopene content flowering significantly increased fruit setand fruit enlargement of the moderate water deficit (MD), the other time periods andthe degree of loss of water were significantly lower; prototype Vc content floweringfruit set period of mild water deficit (LD) is higher than the ck other treatments werelower than ck, treatments had no significant effect; significantly increased the totalacidity the seedling mild water deficit (LD), other treatments had no significant effect;pH value of each period of treatment were higher than ck, seedling mild loss of water(LD) and harvested mid-term water deficit (MD) was significantly improved, theother treatments had no significant effect; soluble solids significantly improve thecontent of flowering fruit setting of mild water deficit (LD) and a moderate waterdeficit (MD), harvested mid-term degree loss of water (MD) was significantlydecreased, and the other treatments had no significant effect.4. Irrigation amount of the ck>T3>T1>T7>T4>T5>T2>T8>T6, the different lossof water of various periods compare ck>LD>MD, processing non-significant difference; irrigation water use efficiency, T8>T3>T4>T6>T2>T7>T5>T1>ck,treatments are no significant differences.Experimental mild and moderate loss of water to reduce the processing tomatogrowth and photosynthetic daily accumulation of regulated deficit irrigation on fruitquality and flavor, harvest mid-term water deficit (MD) of the experimental treatmentthe highest irrigation water use efficiency.