Effects Of Irrigation Staee And Amount On Yield And Quality In Super-high-yield Wheat

The research was carried out at experiment station in super-high-yield land of Jinhai seed limited company, Yantai, from2009to2011. Under field condition, Jimai22were used to study the effects of irrigation amount and irrigation stage on yield and quality in super-high-yield wheat. According to different irrigation amount and irrigation stage, we set nine treatments in the experiment, which were in turn:no irrigation (CK); irrigation at jointing stage (T1); irrigation at jointing and filling stage (T2); irrigation at wintering and jointing stage (T3); irrigation at getting and booting stage (T4); irrigation at wintering, jointing and filling stage (T5); irrigation at wintering, getting and booting stage (T6); irrigation at wintering, getting, jointing, filling stage (T7); irrigation at wintering, getting, jointing, booting, filling stage (T8). And each time the irrigation amount was60mm. The main results were as following:1. Effects of irrigation stage and amount on dry matter accumulation of super-high-yield wheat after anthesisThe results showed that irrigation had significant regulating action on dry matter accumulation after anthesis in super-high-yield wheat. Reasonable irrigation amount and irrigation stage of super-high-yield wheat was beneficial to increase the dry matter accumulation of wheat, enhance biological yield, keep high filling rate of wheat after anthesis, and promote the formation of grain weight. In the range of0-300mm irrigation amount, as the irrigation amount was increased, the contribution ratio of assimilate in nutritive organ after anthesis raised, which offset the fall of the nutritive organ contribution to grain, and at last transport of assimilate in nutritive organ (especially leaves)to grain was enhanced. Moreover compared to other treatments, the average filling rate after anthesis of T5was the biggest, the assimilate transport amount of nutritive organ in T5was the highest (1.285g/stalk), and at mature period grain weight of T5was supreme (45.02mg/grain).2. Effects of irrigation stage and amount on sugar content of super-high-yield wheat after anthesisWe found that after anthesis in flag leaf of super-high-yield wheat both sucrose content and soluble sugar content arose at first and then fell. When sucrose content and soluble sugar content of flag leaf reached peak value, they dropped rapidly, and at maturity stage sucrose content and soluble sugar content in flag leaf came up to bottom. But after anthesis in grain of super-high-yield wheat both sucrose content and soluble sugar content which up to the lowest at maturity stage decreased gradually. Compared to the CK treatment, irrigation increased the metabolic activity of soluble sugar and sucrose of Super-high-yield wheat at filling stage. Among the rest soluble sugar content and sucrose content in super-high-yield wheat of T5treatment were the highest and the transformation of soluble sugar and sucrose was the most thorough. Continuing to increase irrigation amount (T7and T8) the metabolic activity of soluble sugar and sucrose were decreased significantly.3. Effects of irrigation stage and amount on the flag leaf senescence of super-high-yieid wheat after anthesisThe results showed that irrigation could greatly adjust flag leaves senescence characteristics of super-high-yield wheat after anthesis. At filling stage POD, SOD, and CAT activity of flag leaves in super-high-yield wheat were downtrend, and the final product of lipid peroxidation (MDA) of flag leaves in super-high-yield wheat was uptread. Besides compared to CK treatment irrigation increased the chlorophyll content (SPAD value), LAI, POD, SOD, CAT activity of flag leaves in super-high-yield wheat, decreased the the final product of lipid peroxidation (MDA) of flag leaves in super-high-yield wheat. Continuing to increase irrigation amount (T7and T8) the chlorophyll content (SPAD value) and LAI dropped, POD, SOD, CAT activity had little rate of increased amplitude, while all kinds of protective enzymes activity got the maximum improve, and the flag leaf senescence of T5treatment was obviously delayed.4. Effects of irrigation stage and amount on photosynthetic characteristics of super-high-yield wheat after anthesisThe results showed that in the range of0-300mm irrigation amount, irrigation had significant regulating action on photosynthetic characteristics of super-high-yield wheat after anthesis. Compared to the control, irrigation significantly increased the SPAD value in flag leaf and LAI, and made the super-high-yield wheat maintain relatively superior leaf structure and functional status which was the precondition to super-high-yield. Besides, as the irrigation amount was increased, the stomatal conductance and transpiration rate rose, the intercellular CO2concentration dropped, and the net photosynthesis rate increased. Up to the treatment T5which was irrigated60mm at wintering, jointing and filling stage respectively, all the photosynthetic indexes in flag leaf coordinated, the net photosynthesis rate was the highest at filling stage. Continuing to increase irrigation amount, the flag leaf senescence was accelerated, the photosynthetic indexes were disordered, and the net photosynthesis rate dropped.5. Effects of irrigation stage and amount on water consumption characteristics and yield of super-high-yield wheatThe results showed that before jointing stage soil water of super-high-yield cornfield mainly was consumed in the form of surface evapo-transpiration, so large irrigation caused water resources waste while had no benefit to yield. Under dry conditions, super-high-yield wheat used more soil storage water, as a result the water use efficiency of super-high-yield wheat was superior, but the yield was lower than others. As the irrigation amount was increased, the total water consumption amount and yield arose in step, and T5treatment had the maximum yield. Under same irrigation amount conditions, irrigation was further benefit to super-high-yield cornfield in late growth stage than in early growth stage. Continuing to increase irrigation amount total water consumption amount of super-high-yield wheat in T7and T8treatments was increased further up, but the yield of super-high-yield wheat in T7and T8treatments dropped, eventually water use efficiency of super-high-yield wheat in T7and T8treatments was reduced.6. Effects of irrigation stage and amount on quality of super-high-yield wheatThe results showed that irrigation stage and amount had notably impact on the of super-high-yield wheat. Compared to CK treatment, with the increase of irrigation amount grain amylase content of super-high-yield wheat and protein percentage content declined, amylopectin content, total amount of starch and protein content were increased. Besides as the irrigation amount was increased processing quality indexes of super-high-yield wheat, such as dough stabilizing time, dry gluten content and wet gluten content, zeleny and flour extraction rate, were increased. Thereinto super-high-yield wheat of T5treatment had the optimal quality indexes. Continuing to increase irrigation amount processing quality indexes of super-high-yield wheat in T7and T8treatments had not been improved, even dropped. Thus under these experimental conditions, irrigated60mm at wintering, jointing and filling stage respectively was the feasible irrigation scheme to super-high-yield land, which had super high yield and high quality at the same high WUE.