Effect Of Different Irrigation Patterns On Forming Of Carbohydrate Of Japonica Rice In Cold Region

Heilongjiang Province is one of the important commodity grain producing area and the mainproduction base of the japonica rice in China.Currently, in heilongjiang province and China thecontradiction between supply and demand of water resources is increasingly serious. Therefore,cold japonica rice in water-saving irrigation cultivation can effectively alleviate the shortage ofwater resources,improve water productivity,protect the sustainable development of cold japonicarice has important strategic significance.In this thesis,cold japonica rice Dongnong425andDongnong427was used as experimental material, setting five irrigation patterns, normalirrigation(A),moderate dry-wet alternate irrigation(B),system dry-wet alternate irrigation(C),severe dry-wet alternate irrigation(D) and dry farming(E).The effects of different irrigationpatterns on the carbohydrates content in the function leaves,the starch content and starchcomponents of Japonica rice in cold region were studied.Clear dry matter accumulation and itsyield formation rule under different irrigation patterns.Reveal the regulation effect ofcarbohydrates formation key enzymes,To clarify the mechanism of rice carbohydrates formationunder different irrigation patterns.This theory can determine a optimum irrigation patterns, and toprovide a theoretical basis and technical support for the water-saving cultivation technique injaponica rice. The main results of this experiment are as follows:1.From dominate tillering stage to milk stage, the content of sucrose, fructose and totalsoluble in the function leaves of Dongnong425and Dongnong427increased in the function leaveswith the decrease in the soil water potential. From dough stage to complete ripe stage, the contentof sucrose treatment higher than other treatments. In the whole growth period, Two varieties ofrice total soluble content in the function leaves of B treatment keep a high level. After milk stage,total soluble content of D,E treatment is low and the decline is more obvious. The same growthperiod, the sucrose, fructose and total soluble content in the function leaves of Dongnong425higher than Dongnong427.2.From dominate tillering stage to milk stage,the activity of sucrose phosphate synthase(SPS)in the function leaves of Dongnong425and Dongnong427decreased in the function leaves withthe decrease in the soil water potential. From milk stage to complete ripe stage, SPS activity of Btreatment higher than other treatments. In the whole growth period, Two varieties of rice sucrose,fructose content in the function leaves and SPS activity showed significant or highly significantpositive correlation. In tillering stage and booting stage, total soluble content and SPS activityshowed negative correlation, and in dough stage and complete ripe stage, both reached highly significant level.3.With the development of growth stages, Shoot dry weight of Dongnong425and Dongnong427decreased with the decrease in the soil water potential.And dry weight in different organs of Atreatment not significant different with B treatment. Dry weight allocation proportion is differentin the two periods, effect of different irrigation patterns on each organ content in heading stageshows: whole plant＞stems and leaf＞ear, and in mature stage shows: whole plant＞ear＞stemsand leaf.In the same growth period, shoot dry weight on each treatment of Dongnong425higherthan Dongnong427.4.Stem and sheath output,stem and sheath output rate and stem and sheath conversion rate ofDongnong425and Dongnong427shows: B treatment significant higher than the other threetreatment. From heading stage to mature stage,the content of total soluble and starch in stem andsheath of B treatment at a higher level, both the running rate and contribution rate of stem andsheath are bigger. Shoot dry weight, output, output rate and conversion rate in stem and sheath oneach treatment of Dongnong425higher than Dongnong427.5.In the whole growth period, the activity ADPG pyrophosphorylase and (Q-enzyme)decreased with the decrease in the soil water potential.The two enzymes activity of B treatmentdecreased the relatively flat amplitude, The two enzymes activity of D and E treatmentSignificantly lower than the other three treatments.6.The starch and starch component content increase gradually during the rice grain fillin. Thestarch and starch component content decreased with the decrease in the soil water potential.Inmature stage, The content of starch and starch component on A treatment not significant differentwith B treatment, and significant different with the other treatments, the content of starch andstarch componenton D and E treatment Significantly lower than the other treatments.7.At14d,21d after heading, the activity of ADPG pyrophosphorylase was significantlypositive or very significantly positive correlated with amylose stach content. At21d~35d afterheading, the activity of ADPG pyrophosphorylase was significantly positive or very significantlypositive correlated with total stach conten. At21d after heading, the Q-enzyme activity wassignificantly positive or very significantly positive correlated with amylopectin and total starchcontent.8.In addition to the effective panicles per unit area was more unter B treatment of Dongnong425and Dongnong427,the other yield components and yield formation were largest of Atreatment.The yield of A treatment not significant different with B treatment,the yield and yieldcomponents of D,E treatment were significantly lower than the other three treatment.9.Rainfall accounts for the proportion of the total water consumption increased with thedecrease in the soil water potential.The yield of A treatment not significant different with Btreatment,and B treatment has a higher the water use efficiency and irrigation water use efficiency.Considering B treatment is more economical water-saving irrigation mode.The water use efficiency and irrigation water use efficiency of Dongnong425was higher than Dongnong427,Dongnong425was more water saving than Dongnong427.