Effects Of Water Stress And Rewatering On Growth Development And Photosynthetic Characteristics To Suger Beet

In order to clear the effect of the stage of soil water stress on sugar beet production in cold and arid region of north, in 2013-2014 in hebei agricultural university, zhangjiakou Zhang Bei experiment stations, in pool culture, artificial anti-canopy planted pool and irrigation control soil moisture, simulate natural arid environments, set up after water stress and water stress test and reused in different periods in artificial proof canopy. To provide the basis of water management for the sugar beet fields,, monitored the beet growth, quality, photosynthetic and yield of different growth periods water shortage and rewatering, The result showed that, 1. Effects of water stress and rewatering on sugar beet water consumptionCk of sugar beet growth period of field water consumption is 314.45 mm at sandy chestnut soil in 2013. After water stress, the field water consumption decreased significantly, ah、bh、ch and dh were decreased by 74.69%、52.97%、32.53% and 13.11% with ck, the difference was extremely significant; after rewatering, the field waters consumption increased, as、bs and cs were decreased by 31.19%、29.86% and 10.03% with ck. ck of sugar beet growth period of field water consumption is 314.45 mm at sandy chestnut soil in 2014. Water consumption of sugar beet under water stress field water consumption of 34.32 ~ 222.32 mm less than ck, compared with ck was reduced by 11.10% ~ 71.91%, with the duration of water stress, the less of water consumption.Ah is the earliest time of stress, the filling water is 48 mm, 55% of the total water consumption, Other water stress treatment of filling water accounts for over 74% of the total water consumption.After rewatering, the increase of irrigation amount, the water consumption of sugar beet field increased, the treatment of rewatering were decreased by 6.16%~31.10% with ck, and sugar beet full use of soil moisture to compensate for the stagnation of growth caused by water stress. The field water consumption is 310.96 mm at meadow chestnut soil, the soil moisture was significantly greater than that of sand soil. 2. Effects of water stress and rewatering on sugar beet growthah、bh、ch and dh were decreased by 27.14%、14.47%、2.10% and 1.71% with ck of plant height, 41.38%、53.18%、36.12% and 17.79% of leaf number, 66.98%、59.01%、41.19% and 18.40% of leaf area, 46.72%、42.36%、33.55% and 20.18% of root diameter at sandy chestnut soil in 2014. Rewatered treatments could sustain and increase the plant height, leaf area and root thick, but could not supply the same amount of compensationcompared to control. as、bs、cs and ds were decreased by 27.14%、14.47%、2.10% and 1.71% with ck of plant height, 20.15%、18.87%、11.07% and 5.63% of leaf number, 40.01%、29.47%、17.44% and 6.11% of leaf area, 20.54%、17.81%、11.91% and 4.81% of root diameter.Water stress of different period significantly inhibited the plant height, leaf area and root thick of the beet. Rewatered treatments could sustain and increase the plant height, leaf area and root thick, but could not supply the same amount of compensation compared to control. The total number of leaves and leaf size aboveground become prerequisite to ensure high and stable yield on the sugar beet early growth stage such as seedlings and leafage growth. The number of functional leaves and shoots of the length of the blade features for ensuring the protection of high-yield on the sugar beet later growth stage such as root enlargement stage and sugar accumulating stage. Therefore, Early ” to increase the number of leaves and leaf area ”, late “to protect the blade and function time “is a field moisture control technology measures to improve the sugar beet production stable high yield. 3. The effect of water stress and rewatering on Photosynthesis and Chlorophyll Fluorescence of the Sugar BeetIn the whole growth period the Sugar Beet water replenishing stress(ck), different periods transpiration rate(Tr) and net photosynthetic rate(Pn) change nearly "unimodal type"; water shortage presents "Twin Peaks" characteristics. Water stress decreases DPC, DTC and raises WUEd, and extends Pn and the time of Tr; rewatering makes Tr and Pn recover, but it can’t reach is not affected by water stress level. After water stress, sugar beet DPC shows upward trend in the late. This suggests that the sugar beet is gradually adapt to water stress on leaf damage.The results indicated that Ls day under extremely dry environmental changes have a midday trough "Twin Peaks" feature, and ci a "double-dip" but not with the timing of reverse Ls. Accordingly, as the water stress, the effect of stomatal factors was reducing, the non-stomatal factor namely the mesophyll cells of photosynthetic activity factor was increasing; water stress leads to inhibition of photochemical reaction center PSⅡ midday and inactivation, which becomes the water stress as the basic mechanism to make sugar beet Pn inefficient. 4. Effects of water stress and rewatering on quality and production of sugar beetThe water stress was beneficial to increase the sugar content of sugar beet, the earlier time of water stress in the growth period, the higher of sugar content in root in the harvest; rewatering made the sugar content of sugar beet reduce, and the sugar content was lower than what in CK. The sugar content of sugar beet under water stress in 2013 was higher than what in CK 0.44 percent to 5.57 percent, which was higher than what in CK 2.38 percent to 7.60 percent in 2014. The sugar content of sugar beet under rewatering in 2013 was higher than what in CK 0.88 percent to 2.57 percent, which was higher than what in CK 0.39 percent to 2.49 percent in 2014.The water stress decreased the production of sugar beet root significantly. The treatment under water stress’ s economic production reduced 7.44%~85.08% of CK in 2013, which in sandy chestnut soil decreased 27.60%~82.03% of CK in 2014; after rewatering in 2013 the production of sugar beet decreased 17.56%~49.75% of CK, which in 2014 decreased 2.19%~43.00% of CK; and the production of sugar beet in loamy meadow chestnut soil has the same change trend. The production of dh in 2013, cs and ds in sandy chestnut soil in 2014, ds in loamy meadow chestnut soil in 2014 had no significant difference. Farmland water management is the important measure to effect the production of sugar beet root. 5. The relationship between the characteristics of sugar beet.The water consumption in the growth of sugar beet has very significant positive correlation to production of root, which has very significant negative correlation to sugar content in harvest. Faced to the very dry weather in the Cold and Arid area in North Hebei, it is impossible to have too much precipitation in the growth of sugar on dry land, so the water moisture regulation and control of moisturizing in the drought of early growth period and functional leaf numbers guarantee in the drought of later growth period, which makes the key technique to give consideration to both sides of quality and production of sugar beet.