摘要：【目的】通過比較分析不同鉬氮配比處理下兩種小麥莖稈形態特征，基部莖節粗細胞壁組分及莖稈力學特征變化，探究鉬氮配施對小麥抗倒伏性的影響機制?！痉椒ā恳?7003（小麥鉬高效品種）和97014（小麥鉬低效品種）為材料，采用隨機區組試驗設計，設置4個施氮水平(N 0 kg/hm2，N 120 kg/hm2，N 210 kg/hm2，N 300 kg/hm2) ，3個施鉬水平((NH4)2MoO4 0kg/hm2，(NH4)2MoO4 0.75 kg/hm2，(NH4)2MoO4 1.50kg/hm2)，比較不同處理的倒伏率，并從生理學、形態學和力學指標等方面，分析小麥倒伏差異的原因?！窘Y果】1)小麥鉬低效品種97014在相同的氮、鉬水平下折斷處到頂端的距離和彎曲力矩均高于小麥鉬高效品種97003；相比不施氮，施氮三水平均可提高兩品種小麥上部鮮重和彎曲力矩，其中在氮水平為210 kg N/hm2下差異較為明顯，施氮對斷面系數和彎曲應力有顯著影響，在施氮水平0 kg N/hm2和210 kg N/hm2時，折斷彎矩會隨著施鉬量的增加而增加；2)小麥鉬高效品種97003基部節長在各個鉬、氮施肥水平下均高于小麥鉬低效品種97014，而上部節長和穗長均低于小麥鉬低效品種97014；小麥鉬高效品種97003的莖稈長短軸外徑及長軸內徑和穗長均隨著施氮水平的增高而增加，小麥鉬低效品種97014的莖稈長短軸外徑及長軸內徑、基部莖長和穗長均隨著施氮水平的增高而增加；3)隨著氮肥用量的增加，小麥莖稈非結構性碳水化合物顯著降低，小麥鉬高效品種97003施0.75 kg 鉬酸銨/hm2可減少小麥莖稈非結構性碳水化合物量；4)兩品種小麥基部纖維素、木質素含量有所差異。小麥鉬高效品種97003纖維素、木質素含量在各個處理水平下基本不變，小麥鉬低效品種在4個氮水平下配施1.5 kg 鉬酸銨/hm2均增加了纖維素含量，在施氮水平210 kg N/hm2和120 kg N/hm2下配施0.75 kg/hm2鉬酸銨，基部節間木質素含量下降?！窘Y論】不同鉬氮配施量下的2品系冬小麥莖稈主要物理性狀優化組合不同，基部節間短而粗，莖壁厚度大，結構性碳水化合物總量增大，莖稈充實程度好，是冬小麥抗折力大、倒伏指數小、增強抗倒伏能力的直接原因。
Abstract: 【Objective】By comparing and analyzing the 2 varieties winter wheat changes of stem morphological characteristics, basal node coarse cell wall composition and stem mechanical characteristics under different molybdenum-nitrogen ratio treatments, to explore the effect of molybdenum and nitrogen combined application on lodging resistance of winter wheat. 【Method】 By using 97003 and 97014 as materials, four nitrogen application levels (N 0 kg/hm2, N120 kg/hm2, N 210 kg/hm2, N 300 kg/hm2) and three Mo application levels ((NH4)2MoO4 0 kg/hm2, (NH4)2MoO4 0.75 kg/hm2 and (NH4)2MoO4 1.5 kg/hm2 were set up to compare the lodging rate of different, and the reasons of wheat lodging difference were analyzed from physiological, morphological and mechanical indexes. 【Result】 1) The distance from the break to the top and the bending moment of the wheat molybdenum low-efficiency cultivar 97014 at the same nitrogen and molybdenum levels were higher than those of the wheat molybdenum high-efficiency cultivar 97003; compared with no nitrogen application, the three levels of nitrogen application could increase both varieties of wheat the upper fresh weight and bending moment, the difference was more obvious when the nitrogen level was 210 kg N/hm2, nitrogen application had a significant effect on the section coefficient and bending stress. The nitrogen level was 0 kg N/hm2 and 210 kg N/hm2 , the bending moment would increase as the amount of molybdenum applied increases; 2) The basal node length of wheat variety 97003 was higher than that of wheat variety 97014 under all Mo and N fertilization levels, while the upper node length and ear length were lower than that of wheat variety 97014; the outer diameter of long axis and the inner diameter of long axis and ear length of wheat molybdenum efficient variety 97003 increased with the increase of nitrogen application level In addition, the outer diameter and inner diameter of long axis, basal stem length and ear length of wheat variety 97014 increased with the increase of nitrogen application level; 3) With the increase of nitrogen application rate, the non structural carbohydrate of wheat stem decreased significantly, and the application of (NH4)2MoO4 1.5 kg/hm2 efficient wheat variety 97003 was observed Ammonium Molybdate / hm2 can reduce the amount of non structural carbohydrate in wheat stem; 4) The cellulose and lignin content in the base of two wheat varieties were different. The cellulose and lignin contents of 97003 wheat variety with high molybdenum efficiency were basically unchanged under all treatment levels. The cellulose content of wheat variety 97003 with low molybdenum efficiency was increased by applying (NH4)2MoO4 1.5 kg/hm2 under four nitrogen levels. The lignin content of basal internode decreased when 0.75 kg/hm2 (NH4)2MoO4 was applied at 210 kg N/hm2 and 120 kg N/ hm2 . 【Conclusion】 The optimal combination of the main physical properties of the two winter wheat lines under different Mo and N application rates were different. The short and thick basal internode, large stem wall thickness, increased total amount of structural carbohydrates and good stalk plumpness were the direct reasons for the high bending resistance, small lodging index and enhanced lodging resistance of winter wheat.