【目的】探讨黄河流域北部棉区应用缩节胺(1,1-dimethyl-piperidinium chloride,DPC)对棉花进行化学封顶的可行性。【方法】于2012—2014年在河北省河间市瀛州镇国欣科技园和北京市中国农业大学上庄实验站进行,共包括6个独立试验。供试...【目的】探讨黄河流域北部棉区应用缩节胺(1,1-dimethyl-piperidinium chloride,DPC)对棉花进行化学封顶的可行性。【方法】于2012—2014年在河北省河间市瀛州镇国欣科技园和北京市中国农业大学上庄实验站进行,共包括6个独立试验。供试棉花品种为国欣棉3号(GX3)、欣抗4号(XK4)、石抗126(S126)和欣试17(XS17)。DPC化学封顶技术分为单独应用常规DPC化控技术(简称DPC)、将常规DPC化控技术与增效型DPC(简称DPC+)相结合(简称DPC+DPC^+)两种方式,以在常规DPC化控基础上进行人工打顶(简称DPC+MT)为对照。【结果】2012和2013年花铃期(7—8月份)多雨,应用DPC化学封顶技术的棉株较高、新生果枝数较多,其中株高较DPC+MT增加10.6—12.3 cm,果枝数增加5.8—7.9台。2014年花铃期干旱少雨,DPC化学封顶的株高与DPC+MT相比无显著差异,新生果枝数不超过3台。DPC化学封顶对棉花产量的影响不显著,但可发现2012年DPC+DPC^+的产量表现出降低趋势,且上部果枝成铃少、新生果枝成铃多,群体熟期有推迟现象。2013和2014年DPC+DPC^+的产量和熟期则与对照相当或略有增减。DPC+的应用时间(7月中旬至7月底)和剂量(750—1 500 m L·hm^(-2))对棉花株型及产量的影响无显著差异,但应避免在结铃盛期(7月底)应用大剂量DPC+(1 500 m L·hm^(-2)),以防延长后期棉铃的成熟。与DPC+DPC^+相比,单独应用常规DPC化控技术进行化学封顶在多雨年份或高密度下对棉株的控长强度较弱,而且存在减产风险。【结论】应用DPC进行化学封顶在黄河流域北部棉区基本可行,实际应用时需要根据气象因子和种植密度决定单独应用常规DPC化控技术还是将常规DPC化控技术与增效型DPC的应用相结合。展开更多
缩节安(1,1-dimethyl piperidinium chloride, DPC)是棉花生产中广泛应用的植物生长延缓剂。增效DPC (DPC+,25%水剂)助剂中的成分能对植物幼嫩组织表面形成轻微伤害,实践证明其可实现棉花化学封顶、起到替代人工打顶的作用。为探究DPC+...缩节安(1,1-dimethyl piperidinium chloride, DPC)是棉花生产中广泛应用的植物生长延缓剂。增效DPC (DPC+,25%水剂)助剂中的成分能对植物幼嫩组织表面形成轻微伤害,实践证明其可实现棉花化学封顶、起到替代人工打顶的作用。为探究DPC+作用机制,本试验于2015年在田间条件下研究了棉花盛花期后(7月24日)应用DPC+(1125 mL hm–2)对棉花主茎生长和顶芽解剖结构、氧化还原状态及相关基因表达的影响。结果表明,与对照(同期喷施清水)相比, DPC+处理后棉花株高降低,白花以上节位(nodes above the last white flower, NAWF)更早降到5;处理后3 d即可观察到主茎生长点较对照扁平,生长点的纵横比显著低于对照;处理后6 h棉花顶芽的O2-、H2O2和MDA含量高于对照,而开花相关基因GhSPL3和GhV1及顶端分生组织相关基因GhREV3的表达量则低于对照。化学封顶剂DPC+可引起棉株顶芽的短期氧化应激反应,降低与主茎生长点发育和花芽分化相关基因的表达水平,从而延缓棉株生长和花芽的产生,实现化学封顶。展开更多
Plant growth regulators(PGRs)are frequently used to adjust cotton growth and development.The objectives of this study were to determine how PGRs affect plant morphology,light distribution and the spatial distribution ...Plant growth regulators(PGRs)are frequently used to adjust cotton growth and development.The objectives of this study were to determine how PGRs affect plant morphology,light distribution and the spatial distribution of leaves and bolls within the cotton canopy.The field experiments were carried out at Shihezi(Xinjiang Uyghur Autonomous Region,China)in 2014 and 2015.The experiment included two PGR treatments:(i)flumetralin(active ingredient(a.i),N-N-ethy)-2,6-dinitro-4-aniline and(i)mepiquat chloride(ai,1-dimethyl-piperidiniuchloride)plus flumetralin.No PGR(manual topping)was applied in the control treatment.The chemically-topped plants were taller and had more main stem internodes than the manually-topped plants.Furthermore,the PGRs significantly reduced the length of fruiting branches in the upper canopy,resulting in a more compact canopy.The maximum leaf area index was signifcantly greater in the chemically-topped treatments than that in the control.In particular,the PGRs increased leaf area index by 25%in the upper canopy.The leaf area duration was also longer in the chemically-topped treatments than in the control.Compared with the control,the chemically-topped treatments increased canopy diffuse non-interceptance by 35.75%in the upper canopy layer,while reducing the fraction of intercepted photosynthetically active radiation by 14.45%in the upper canopy layer.Light transmittance in the upper and middle canopy layers was greater in the chemically-topped treatments than in the control,which increased boll numbers in both the upper canopy and the middle canopy.However,the chemically-topped treatments resulted in less light-leakage through the lower canopy layer during the late growth stages,which had a tendency to increase boll numbers in the whole canopy.In summary,the PGRs optimized canopy shape,light distribution and the spatial distribution of bolls and leaves.展开更多
文摘【目的】探讨黄河流域北部棉区应用缩节胺(1,1-dimethyl-piperidinium chloride,DPC)对棉花进行化学封顶的可行性。【方法】于2012—2014年在河北省河间市瀛州镇国欣科技园和北京市中国农业大学上庄实验站进行,共包括6个独立试验。供试棉花品种为国欣棉3号(GX3)、欣抗4号(XK4)、石抗126(S126)和欣试17(XS17)。DPC化学封顶技术分为单独应用常规DPC化控技术(简称DPC)、将常规DPC化控技术与增效型DPC(简称DPC+)相结合(简称DPC+DPC^+)两种方式,以在常规DPC化控基础上进行人工打顶(简称DPC+MT)为对照。【结果】2012和2013年花铃期(7—8月份)多雨,应用DPC化学封顶技术的棉株较高、新生果枝数较多,其中株高较DPC+MT增加10.6—12.3 cm,果枝数增加5.8—7.9台。2014年花铃期干旱少雨,DPC化学封顶的株高与DPC+MT相比无显著差异,新生果枝数不超过3台。DPC化学封顶对棉花产量的影响不显著,但可发现2012年DPC+DPC^+的产量表现出降低趋势,且上部果枝成铃少、新生果枝成铃多,群体熟期有推迟现象。2013和2014年DPC+DPC^+的产量和熟期则与对照相当或略有增减。DPC+的应用时间(7月中旬至7月底)和剂量(750—1 500 m L·hm^(-2))对棉花株型及产量的影响无显著差异,但应避免在结铃盛期(7月底)应用大剂量DPC+(1 500 m L·hm^(-2)),以防延长后期棉铃的成熟。与DPC+DPC^+相比,单独应用常规DPC化控技术进行化学封顶在多雨年份或高密度下对棉株的控长强度较弱,而且存在减产风险。【结论】应用DPC进行化学封顶在黄河流域北部棉区基本可行,实际应用时需要根据气象因子和种植密度决定单独应用常规DPC化控技术还是将常规DPC化控技术与增效型DPC的应用相结合。
文摘缩节安(1,1-dimethyl piperidinium chloride, DPC)是棉花生产中广泛应用的植物生长延缓剂。增效DPC (DPC+,25%水剂)助剂中的成分能对植物幼嫩组织表面形成轻微伤害,实践证明其可实现棉花化学封顶、起到替代人工打顶的作用。为探究DPC+作用机制,本试验于2015年在田间条件下研究了棉花盛花期后(7月24日)应用DPC+(1125 mL hm–2)对棉花主茎生长和顶芽解剖结构、氧化还原状态及相关基因表达的影响。结果表明,与对照(同期喷施清水)相比, DPC+处理后棉花株高降低,白花以上节位(nodes above the last white flower, NAWF)更早降到5;处理后3 d即可观察到主茎生长点较对照扁平,生长点的纵横比显著低于对照;处理后6 h棉花顶芽的O2-、H2O2和MDA含量高于对照,而开花相关基因GhSPL3和GhV1及顶端分生组织相关基因GhREV3的表达量则低于对照。化学封顶剂DPC+可引起棉株顶芽的短期氧化应激反应,降低与主茎生长点发育和花芽分化相关基因的表达水平,从而延缓棉株生长和花芽的产生,实现化学封顶。
文摘在北疆气候条件下,为明确棉花对不同施氮量下增效缩节胺[DPC+,25%甲哌鎓(1,1-dimethyl piperidinium chloride,DPC)水剂]化学封顶效应的响应,以新陆早53号为试验材料,在150(N1)、300(N2)和450(N3)kg hm^-2施氮水平下,以人工打顶(P0)为对照,研究DPC+剂量[450(P1)、750(P2)和1050(P3)mL hm^-2]对棉花叶绿素含量(Chl)、叶面积(LA)、气体交换参数、叶绿素荧光参数及干物质累积与分配的影响。结果表明,同一DPC^+剂量下,随施氮量增加,Chl、LA、气体交换参数、叶绿素荧光参数和生殖器官干物质(RODM)均呈现先上升后下降的趋势;同一施氮量下,上述参数因DPC+剂量不同呈不同变化趋势,其中N1水平下以P1处理、N2水平下以P2处理、N3水平下以P3处理表现出较高的RODM、Chl、净光合速率(Pn)、实际光化学效率(ФPSII)、电子传递速率(ETR),较低的非光化学淬灭(NPQ)。DPC^+与施氮量互作表现为,与其他处理相比,Chl、Pn、蒸腾速率(Tr)、气孔导度(Gs)、ФPSII、ETR、RODM在N2P2处理下分别提高了15.52%、29.39%、27.97%、36.77%、23.28%、23.55%、8.41%~22.24%,NPQ降低了34.54%。相关分析表明,干物质累积和Chl、LA、Pn、Gs、ФPSII均呈显著正相关,与NPQ呈极显著负相关。因此,在喷施DPC+(750 mL hm^-2)条件下,适量追施氮肥(300 kg hm^-2)能改善棉花光合性能,在增加干物质累积的基础上,促进了光合产物向生殖器官分配。
基金This study was financially supported by the 948 Program from Ministry of Agriculture of China(2016-X25)the National Key Technology R&D Program of China(2014BAD09B03)The authors are grateful to Dr.William J.Gale(Shihezi University,China)for his helpful revision of the paper especially in English language.
文摘Plant growth regulators(PGRs)are frequently used to adjust cotton growth and development.The objectives of this study were to determine how PGRs affect plant morphology,light distribution and the spatial distribution of leaves and bolls within the cotton canopy.The field experiments were carried out at Shihezi(Xinjiang Uyghur Autonomous Region,China)in 2014 and 2015.The experiment included two PGR treatments:(i)flumetralin(active ingredient(a.i),N-N-ethy)-2,6-dinitro-4-aniline and(i)mepiquat chloride(ai,1-dimethyl-piperidiniuchloride)plus flumetralin.No PGR(manual topping)was applied in the control treatment.The chemically-topped plants were taller and had more main stem internodes than the manually-topped plants.Furthermore,the PGRs significantly reduced the length of fruiting branches in the upper canopy,resulting in a more compact canopy.The maximum leaf area index was signifcantly greater in the chemically-topped treatments than that in the control.In particular,the PGRs increased leaf area index by 25%in the upper canopy.The leaf area duration was also longer in the chemically-topped treatments than in the control.Compared with the control,the chemically-topped treatments increased canopy diffuse non-interceptance by 35.75%in the upper canopy layer,while reducing the fraction of intercepted photosynthetically active radiation by 14.45%in the upper canopy layer.Light transmittance in the upper and middle canopy layers was greater in the chemically-topped treatments than in the control,which increased boll numbers in both the upper canopy and the middle canopy.However,the chemically-topped treatments resulted in less light-leakage through the lower canopy layer during the late growth stages,which had a tendency to increase boll numbers in the whole canopy.In summary,the PGRs optimized canopy shape,light distribution and the spatial distribution of bolls and leaves.