中圖分類號:S645.9 獻標志碼:A 章編號:1673-2871(2025)06-152-06
Effects of nitrogen application rate on starch accumulation and starch synthetase activity inSagittariasagittifolia
LIN Zhicheng', JIANG Wen', GAO Meiping', TAO Yunrong2, YANG Qunfang2, LIANG Lingling2 (1.Vegetablechsiuteidemulieniin;glet culturalcienceesearchIstitute,ingle44o,uangxi,ina)
Abstract: Inorder to studythe efects of different nitrogen applicationrateson starch accumulationand the activityof keyenzymesofstarch synthesisduring thedevelopmentofSagitariasagitifolia,fourdifferentnitrogenapplicatiorates were setup with the main variety of S sagittifolia GuiciNo.1 in Guangxi as experimental material.With the increase of nitrogenapplicationrate,thecontentof amylose,amylopectinand total starchincorms increasedatfirstand thendecreased,andN2 treatment ( 240kg?hm-2 had the best effect.The peak time of enzyme activity and starch accumulation rate was not affct bydifferent nitrogen applicationrates,which occurred inthe middle stageofcorm expansion(90 days after planting),and the amylopectinand total starch accumulationrateof N2 treatment had the maximum afterplanting 75and90days.Furthercorrelationanalysisshowedthatthestarchaccumulationratewassignificantlypositivelycorrelated with GBSS,SSS,AGP,and SBEactivity.In general,the starch contentof Guici No.1 isthehighest underN2 treatment( 240kg?hm?2) ,and the reasonable application of nitrogen fertilizer is conducive to the accumulation of starch in S sagittifolia and improvement of quality.
KeyWords:Sagittaria sagitifolia;Nitrogen applicationrate; Starch accumulation; Starch synthase
慈姑是澤瀉科慈姑屬直立水生草本植物,又稱慈菇、茨菇等,原產中國,食用部分為地下球莖,供應冬季蔬菜市場。慈姑作為藥食兩用蔬菜,不僅具有較高的營養價值,還含有多種生物活性成分,有涼血止血、散結解毒、止咳通淋之功效[。慈姑在中國分布于長江流域及其以南各省份,太湖沿岸及珠江三角洲為主產區,北方有少量栽培2。目前廣西栽培面積最大,常年種植面積 4000hm2 以上[3]。
淀粉是慈姑球莖的重要組成部分,含量 (ω ,后同)約為 52.3% (干質量)。淀粉的合成受一系列酶調控,主要有腺嘌呤-葡萄糖焦磷酸化酶(AGPP)顆粒淀粉合成酶(GBSS)、可溶性淀粉合成酶(SSS)、淀粉分支酶(SBE)和去分支酶(DBE)[46]。諸多研究表明,氮肥能影響淀粉的生物合成。吳世雨等在甘薯中研究表明,在塊根膨大過程中,施氮量會對甘薯塊根膨大過程中淀粉含量及特性產生顯著影響,施用氮肥可顯著提高心香和商薯19兩個甘薯品種的淀粉含量。戴明等在玉米中研究表明,施氮可顯著影響寒區春玉米干物質積累和淀粉合成,在較高的氮水平下,玉米干物質積累量、淀粉合成相關酶活性及淀粉積累速率更高。在馬鈴薯中,李勇等選用高淀粉品種克新22號和低淀粉品種克新19號進行研究,結果表明,2個品種塊莖的淀粉產量隨施氮量的增加則呈先增加后降低的趨勢,其中施氮量為 150kg?hm-2 時,高淀粉品種克新22號塊莖的淀粉產量達到最高,為 11.27t?hm-2 ;施氮量為225kg?hm-2 時,低淀粉品種克新19號塊莖的淀粉產量達到最高,為 8.99t?hm-2 。……