Effect Of Non-full Irrigation On Ecological Characteristics Related To Water And Photosynthesis And Crop Productivity Of Jerusalem Artichoke

Under Zhangye climatic condition and planting model with block irrigation, the Qingyu No.2 cultivar was selected as the experimental crop, and the effect of Non-full Irrigation on soil moisture, water consumption, photosynthetic ecological index, economic yield and water use efficiency of Jerusalem artichoke were studied. Seven treatments J1(600m³/ha),J2(1200m³/ha),J3(1200m³/ha),J4(1800m³/ha),J5(1800m³/ha),J6(2400m³/ha) and CK(0m³/ha) under different irrigation quotas in the whole growth stage were established. The main results were as following:1. During the whole growth period, obvious differences existed between different irrigation treatments in soil moisture in 10⁶0cm depth, but the differences in soil moisture within 60¹00cm depth were not obvious; the trend of soil moisture in each soil layer increased at first, then decreased and then continued to increas to seedling, lush foliage, and flowering. After that, soil moisture decreased at first and then increased at buding.2. The trend of daily water consumption in Jerusalem artichoke decreased first, then increased and finally decreased through the whole growth periods. The daily water consumption was 1.97 mm/d at seedling, and 1.04mm/d at lush foliage, which was the highest at buding (3.31mm/d) and the lowest at flowering (0.7mm/d). The water consumption coefficient of Jerusalem artichoke increased from seedling to lush foliage, being the highest at lush foliage (34.8%) and the lowest at flowering(12.6%).3. The trend of soil temperature in each layerwas as follows: 5cm>10cm>15cm>20cm>25cm. The dynamic range of soil temperature in 5¹5cm was much bigger than that in 20²5cm in different irrigation treatments.4. The differences in stem height, leaf area index (LAI), dry matter amount, dry matter accumulation rate of Jerusalem artichoke among different irrigation treatments were significant in p<0.05 or p<0.01 levels. It was the highest in treatment J5 in stem height, leaf area index(LAI), dry matter amount and dry matter accumulation rate.5. Results showed that the yield of Jerusalem artichoke increased with irrigation amount increase from 0m³Â·ha^-1 to 1800m³Â·ha^-1. However, there was no more yield advantage when irrigation amount exceeded to 1800m³Â·ha^-1. The yield of Jerusalem artichoke was determined by the weight per plant, and the yield would increase along with the water consumption amount increase.6. Irrigation amount had a significant effect on water use efficiency(WUE) of Jerusalem artichoke. The WUE of Jerusalem artichoke decreased with irrigation amount increase. The overall trend in different irrigation treatments was: CK>J1>J3>J5>J2>J4>J6.7. Through analyzing the economic benefit of Jerusalem artichoke, J5 had the hightest (11510.10yuan·ha^-1) net income, while the CK, which was the no irrigation treatment, had the lowest(5512.86yuan·ha^-1) net income. Therefor, in the aspects of economic benefit and field practical operation, 3100m³/hm2 of irrigation amout is the optimum index for Jerusalem artichoke in the whole growth period in the study area.