【作者】 周英捷；

【导师】 李伏生；

【作者基本信息】 广西大学 ， 作物栽培与耕作学， 2013， 博士

【摘要】 糯玉米作为鲜食玉米,生育期较短、对产品质量要求高,为提高糯玉米产量、品质、养分和水分利用效率,本文以桂糯518为材料,通过盆栽和大田试验,系统深入地研究了不同施肥水平下,不同生育时期水分调控对糯玉米生理指标、农艺性状、干物质积累、产量及水肥利用的影响,在此基础上提出了糯玉米最佳水肥供应模式。盆栽试验1设不同生育时期(A：苗期—拔节前期、B：拔节后期—孕穗期、C：孕穗期—开花期)亏水和不同程度亏水[重度亏水(35%-45%θf,θf为田间持水量)、中度亏水(45%～55%θf)、轻度亏水(55%-65%θf)和正常灌水(对照CK,65%-80%θf)]。盆栽试验2设7个不同生育期亏水组合和4种施肥水平,亏水组合在3个生育阶段(拔节前期、拔节后—孕穗期、孕穗期—抽雄期),各时期中度、轻度亏水设计来源于盆栽试验1结果,施肥水平设不施肥(F0)、低肥(F1, N、P2O5、K20分别为0.15、0.05、0.15g/kg土)、中肥(F2,分别为0.25、0.10、0.25g/kg土)、高肥(F3,分别为0.35、0.15、0.35g/kg土)。盆栽试验3设2种施肥水平(F1、F2同试验2)和3种水分亏缺组合处理(亏水设计来源于试验2结果选择)。田间试验设4个灌水处理(IT1：孕穗期不灌水、IT2：开花期不灌水、IT3：乳熟期不灌水、IT4：正常灌水)和3个施肥水平(FL1:140kgN,70kgP2O5,140kgK2O/hm2, FL2:180kgN,90kgP2O5,180kgK2O/hm2, FL3:220kgN,110kgP2O5,220kg K2O/hm2]。主要研究结果如下：(1)盆栽条件下,与正常灌水相比,糯玉米苗期—拔节前期亏水处理、拔节后期—孕穗期轻度亏水处理、孕穗期—开花期中轻度亏水处理不显著降低糯玉米鲜或干子粒产量、以干子粒产量为基础的水分利用效率(WUES)、植株NPK吸收总量和土壤速效氮磷含量,而总耗水量减少10.8%～19.9%。拔节后期—孕穗期中度亏水与孕穗期—开花期中或轻度亏水处理、拔节后期—开花期轻度亏水处理也不显著降低糯玉米鲜或干子粒产量和WUEs,而总耗水量减少15.8%-20.3%。拔节后期—孕穗期中度亏水与孕穗期—开花期轻度亏水组合处理也不显著影响植株NPK吸收总量和土壤速效氮磷含量。(2)盆栽条件下,与不施肥相比,施肥提高糯玉米光合速率、叶片水分利用率、鲜或干子粒产量、以干物质量为基础的水分利用效率(WUEt)、WUES和氮磷钾吸收总量,其中中肥水平(F2)提高更显著。F2时,与正常灌水相比,拔节前期中度亏水和拔节后期—孕穗期中或轻度亏水处理(12、13)和拔节前期—抽雄期轻度亏水(15)不显著降低糯玉米鲜或干子粒产量、WUEt、WUEs和植株氮磷钾吸收总量,而总耗水量分别减少9.7%、9.1%和12.5%。但是增加施肥量和任何亏水处理不利于当季肥料利用率的提高。(3)盆栽条件下,与正常灌水相比,13和15处理亏水时糯玉米叶片光合速率(Pn)、蒸腾速率(Tr)和丙二醛含量(MDA)显著降低,而叶绿素(Chl)和可溶性糖含量(SS)有所提高；复水后,其叶片Pn、Tr、Chl、SS和MDA均能恢复达到正常灌水水平。随着施肥水平的提高,叶绿素和可溶性糖含量提高。F2时,与正常灌水相比,13处理不显著影响糯玉米鲜或干子粒产量、植株氮磷钾吸收总量和子粒可溶性糖含量,但是提高WUEs18.7%。(4)大田条件下,与正常灌水相比,各灌水处理并不显著影响孕穗期和开花期叶片生理生化指标；低肥水平时开花期不灌水(IT2)处理提高糯玉米鲜穗产量7.7%、灌水利用效率(IUE)24.4%,中肥水平时孕穗期不灌水或IT2处理鲜穗产量分别提高7.7%和15.4%,IUE分别提高39.9%和33.7%。综上所述,苗期-拔节前期亏水、拔节前期中度亏水+拔节期—孕穗期中或轻度、拔节前期—抽雄期轻度亏水不显著影响叶片生理生化指标、鲜子粒产量及子粒品质,但是提高水分利用效率。中肥水平下,拔节前期中度亏水+拔节后期—孕穗期轻度亏水配合不影响鲜干子粒产量和品质以及植株氮磷钾吸收总量,而提高以干子粒产量为基础的水分利用效率,因此中肥水平和拔节前期中度亏水+拔节后期—孕穗期轻度亏水配合是最佳的水肥供应模式。更多还原

【Abstract】 Sticky maize is the maize for fress food, with shorter growth stage and requirement of high product quality. To increase yield, quality and nutrient and water use efficiency of sticky maize, this study took Gui Nuo518as experimental crop and systematically and in depth investigated the effect of irrigation treatment at different growth stages on physiology, agronomic traits, dry mass accumulation, yield, fertilizer and water use efficiency of sticky maize under different fertilization level using pot and field experiments, and then proposed optimal supply mode of water and fertilizer for sticky maize on the basis of the experimental results. Pot experiment1had water deficit at different growth stages (A:seeding-early joining, B:later joining-booting and C:booting-flowering stages of maize crop) and defferent water deficit levels [serious water deficit (35%-45%θf,θf is field capacity), medium water deficit (45%-55%θf), mild water deficit (55%-65%θf) and normal irrigation (CK,65%～80%θf)]. The pot experiment2had seven water deficit combinations at different growth stages and four fertilization levels, water deficit at three growth stages (early joining, later joining-booting and booting-tasseling stages of maize crop) and medium and mild water deficit at each stage was from the result of the pot experiment1, and four fertilization levels were no fertilization (Fo), low fertilization (F1,0.15g N,0.05g P2O5and0.15g K2O/kg soil); medium fertilization (F2,0.25g N,0.10g P2O5and0.25g K2O/kg soil); high fertilization (F3,0.35g N,015g P2O5and0.35g K2O/kg soil). The pot experiment3had two fertilization levels (F1and F2from the pot experiment2) and three combinations of water deficit (selected from the result of pot experiment2). The field experiment had four irrigation treatments (IT1: no irrigation at the booting stage, IT2:no irrigation at the flowering stage, IT3:no irrigation at the milky stage, IT4:normal irrigation) and three fertilization levels (FL1:140kgN,70kgP2O5and140kgK2O/hm2, FL2:180kgN,90kgP2O5and180kgK2O/hm2, FL3:220kgN,110kgP2O5and220kg K2O/hm2]. The main findings are outlined as follows:(1) Under the pot condition, compared to normal irrigation, water deficit at the seeding-early joining stage, medium water deficit at the later joining-booting and mild or medium at the booting-flowering stages did not reduce fresh or dry seed yield, water use efficiency based on dry seed yield (WUES), total NPK uptakes of sticky maize and soil available N and P contents significantly, but they reduced water consumption by10.8%-19.8%. Mild water deficit at the later joining-booting stage combined with mild or medium water deficit at the booting-flowering stage did not reduce fresh or dry seed yield and WUES significantly, but they reduced water consumption by15.8%-22.8%. Medium water deficit at the later joining-booting combine with mild water deficit at the booting-flowering stages did not significantly reduce the total NPK uptake of plant and soil available N and P content.(2) Under the pot condition, compared to no fertilization, fertilization improved photosynthetic rate, leaf water use efficiency, fresh or dry seed yield, water use efficiency based on total dry mass (WUEt), WUES and total N, P and K uptakes of stick maize, and medium fertilization level (F2) had highest effect. At F2, compared to normal irrigation, medium water deficit at the early joining stage combined with mild or medium water deficit at the later joining-booting stage (I2,13) and mild water deficit at the early joining-tasseling stage (I5) did not significantly reduce fresh or dry seed yield, WUEt, WUES and total NPK uptake of stick maize, but they reduced water consumption by9.7%,9.1%and12.5%, respectively. However, increased fertilization and any water deficit treatment did not improve fertilizer use efficiency at one season.(3) Under the pot condition, at I3and I5treatments, compared to normal irrigation, water deficit reduced photosynthetic rate (Pn), transpiration rate (Tr) and MDA content, but improved chlorophyll content (Chl) and soluble sugar content (SS) slightly. After rewatering, leaf Pn, Tr, Chl, SS and MDA can be restored to the level of the normal irrigation. Chl and SS contents increased with the increase of fertilization level. At F2, compared to normal irrigation, I3treatment did not significantly affect fresh or dry seed yield, total N, P and K uptakes and seed SS content of stick maize, but improved WUES by18.7%. (4) Under the field condition, compared to normal irrigation, any irrigation treatment did not significantly affect physiological and biochemical indices at the booting and flowering stages. At low fertilization level, no irrigation at the flowering stage (IT2) improved fress ear yield of sticky maize by7.7%and irrigation use efficiency by24.4%, and at medium fertilization level, no irrigation at the booting stage and IT2improved fress ear yield of sticky maize by7.7%and15.4%and irrigation use efficiency by39.9%and33.7%, respectively. Fertilization significantly increased soil available K content, but did not significantly affect shoot N, P and K contents and soil available N and P contents.In summary, water feficit treatment at the seeding-early joining stage, medium water deficit at the early joining stage combined with mild or medium water deficit at the later joining-booting stages, mild water deficit at the early joining-tasseling stage did not significantly affect the physiological and biochemical indices, fresh seed yield and seed quality, but increased water use efficiency. At medium fertilizer level, medium water deficit at the early joining stage combined with mild water deficit at the later joining-booting stages did not affect fresh or dry seed yield, seed quality and total N, P and K uptakes, but increased water use efficiency based on dry seed yield. Therefore, medium fertilization level combined with medium water deficit at the early joining stage plus mild water deficit at the later joining-booting stages is the optimal supply mode of water and fertilizer for sticky maize.更多还原