黄腐植酸浸种栽培稻对杂草稻生理生态特性的影响

[目的]研究黄腐植酸浸种栽培稻对杂草稻生理生态特性的影响。[方法]以栽培稻南粳44和杂草稻 JS-Y1为材料,通过田间小区试验研究浓度分别为0（清水对照）、4、6、8 g/L黄腐植酸（Fulvic Acid,FA）浸种栽培稻对不同时期杂草稻分蘖动态、株高、叶绿素含量、光合性能、气体交换参数及产量的影响。[结果]4株/m2杂草稻密度下,随着黄腐植酸浸种浓度上升,杂草稻分蘖数、株高、叶绿素含量、净光合速率（Pn）、气孔导度(Gs)和蒸腾速率(Tr)呈降低趋势,其中4~6 g/L黄腐植酸浸种浓度下,不同时期杂草稻分蘖数较同密度下降13.84%~35.71%,杂草稻萌发后22 d下降幅度最为显著,拔节期杂草稻叶绿素显著下降7.90%-8.88%。而且在4 g/L黄腐植酸浸种浓度下,抽穗期和灌浆期杂草稻株高显著下降6.37%~9.10%;拔节期和抽穗期杂草稻净光合速率、气孔导度和蒸腾速率分别显著下降10.19%~16.05%、12.57%~23.33%和10.28%~19.76%;成熟期杂草稻千粒重、每株有效穗数、单株产量分别显著下降3.19%、21.21%和27.27%。[结论]4株/m2杂草稻密度下,4 g/L黄腐植酸浸种栽培稻可通过调节栽培稻的生长发育状况,改变栽培稻-杂草稻相互间的生态关系,进而影响杂草稻分蘖动态、光合性能和单株产量等生理生态特性,缓解杂草稻对栽培稻的竞争抑制。     

Effects of Free Ammonium and pH on Partial Nitrification Process

Through an activated sludge SBR reactor,the authors study the influence of FA concentration and pH on the partial nitrification of low C/N nitric wastewater.It can be known that low C/N nitric wastewater can realize stable nitrite accumulation to 90%.Maintaining the pH between 6.5~8.5 is suitable for the growth of ammonium oxidation bacteria.While FA rising,the inhibition of ammonium oxidation bacteria is quick,but nitrite oxidation bacteria's is slow.By(adapting) for some time,ammonium oxidation bacteria gain the dominance,and nitrite oxidation bacteria in pessimum,which leads to the nitrite accumulation.Relatively high FA concentration is avail for the competition of ammonium oxidation bacteria.Suitable FA concentration is 7~10 mg/L.Process with long MCRT can not realize stable partial nitrification.The bacillar sludge is its typical feature.     

抗旱节水剂在葡萄栽培上的应用试验研究

通过保水剂、旱地龙、BGA土壤激活剂3种抗旱节水剂在葡萄种植上的田间试验，分析多种抗旱节水剂集成应用对土壤含水率、葡萄产量、葡萄品质(主要指可溶性固形物)的影响。结果表明，保水剂、旱地龙、BGA土壤激活剂在旱地果园的抗旱保墒中均有一定的效果，对于提高葡萄的品质和产量起着积极作用。     

腐殖物质对有机污染物的吸附行为及环境学意义

综述了近年来腐殖物质的研究进展,具体包含以下几个方面的内容:腐殖物质的分离、纯化、元素组成和结构特征及其环境意义。重点讨论了腐殖物质的环境学意义,阐述了腐殖物质主要是胡敏素在吸附疏水性有机污染物的过程中所起到的重要作用,其中包括可溶性腐殖物质的增溶作用和不溶性腐殖物质———胡敏素的吸附固定作用;且对吸附/解吸的机理及一些模型的建立进行了探讨。最后针对研究中面临的问题,提出了今后的重点研究方向。     

叶面喷施FA旱地龙对冬小麦产量和发育期的影响

利用3种不同浓度的抗旱剂(FA旱地龙),在山西省万荣县冬小麦生育的关键期分3次和2次,进行了叶面喷施抗旱试验研究.结果表明:在冬小麦拔节期、孕穗期和灌浆期对叶面喷施一定浓度的抗旱剂,都有明显的抗旱增产效果;在干旱年份,喷施高浓度的抗旱剂比喷施低浓度的抗旱剂增产效果要好,喷施3次比喷施2次的抗旱增产效果好,6种处理的理论产量增产百分率在8.2%～38%之间.喷施抗旱剂主要是提高了冬小麦的抗逆性,提高了土壤水分的利用效率,对提高成穗率、穗粒数和千粒重有利.     

黄腐酸对番茄秧苗运贮过程中内源激素的影响

研究黄腐酸(FA)对番茄秧苗在模拟运贮期间的内源激素的变化。试验结果表明:在秧苗贮运期间,黄腐酸处理的秧苗内源激素IAA、ZR和GA3含量都显著高于在运贮期间没有进行黄腐酸处理的番茄秧苗,ABA含量低于没有进行黄腐酸处理的番茄秧苗。黄腐酸处理可在一定程度上减轻与延缓秧苗运贮中的“胁迫性衰变”,在一定程度上起到保持运贮番茄秧苗质量的作用。     

植物抗旱剂FA旱地龙在草坪草中的应用研究

研究了不同浓度的FA旱地龙处理对高羊茅种子发芽、幼苗抗旱性、耗水量以及茎叶与根系生长的影响。结果表明 :FA旱地龙浸种处理能提高在渗透胁迫下种子的发芽指数与活力指数 ;喷施处理能延缓高羊茅旱害症状的发生 ,减少耗水量 3 %～15 % ;浇灌处理能提高高羊茅茎叶干重、根系生长量、根冠比及根系在深层土壤中的分布 ,从而提高草坪草对干旱胁迫环境的适应能力。     

不同腐殖酸类对黄土坡面侵蚀和养分流失的影响

在陕西省长武县黄土高原农业生态试验站进行了在相同的上方来水量18L/min条件下3种不同腐殖酸类(NHA、BFA、FA)的黄土坡面侵蚀和养分流失的试验,分析了不同腐殖酸类及不同量的同一腐殖酸对土壤侵蚀和养分流失的影响。结果表明:不同量的NHA处理下,径流量均随时间的增加而增加,NHA浓度150,300g/m~2的坡面径流量是500g/m~2的坡面径流量的1.14,1.08倍,含沙率和Br-浓度均随时间的增加而减少,累积径流量、累积泥沙量、累积流失量均随用量的增加而减少,150,300g/m~2的坡面累积泥沙量是用量500g/m~2的2.16,1.87倍,累积Br-流失量是用量500g/m~2的1.38,1.23倍,用量500g/m~2 NHA对防止土壤侵蚀和养分流失的效果最佳;不同浓度FA处理下,径流量随时间的增加而增加,FA浓度为0.1%,0.03%的累积径流量是浓度0.05%的1.19,1.33倍,含沙率和Br-浓度大体随时间的增加而减少,累积径流量、累积泥沙量、累积流失量均随浓度的增加先减少后增加,浓度为0.1%,0.03%的累积泥沙流失量是浓度0.05%的3.03,4.09倍,累积Br-流失总量是0.05%Br-流失总量的1.1,1.26倍,浓度0.5%FA对防止土壤侵蚀和养分流失的效果最佳;不同浓度BFA处理下,径流量随时间的增加而增加,BFA浓度为0.1%,0.05%的坡面累积径流量是浓度0.03%的1.15,1.1倍,含沙率和Br-浓度随时间的增加而减少,累积径流量、累积泥沙量随浓度的增加而增加,累积流失量随浓度的增加先减少后增加,浓度为0.1%,0.05%累积泥沙量是0.03%累积泥沙总量的1.36,0.49倍,Br-流失总量是0.05%Br-流失总量的4.06,3.5倍,浓度0.5%BFA对防止土壤侵蚀和养分流失的效果最佳;综合考虑3种不同腐殖酸类防止坡面侵蚀和养分流失效果为BFAFANHA。     

灌溉方式对设施土壤总有机碳及其腐殖质组分的影响

通过13年连续的番茄栽培灌溉试验,分析了沟灌、滴灌和渗灌3种灌溉处理0—80cm土层土壤有机碳及其腐殖质组分(胡敏酸、富里酸、胡敏素等)含量,探讨了不同灌溉方法对温室土壤有机质变化的影响。结果表明:3种灌溉处理土壤总有机碳、腐殖质各组分含量剖面变化特征一致,均随土层加深而降低,且这一变化主要集中在0—50cm土层,50—80cm土层变化较小。土壤总有机碳及其组分各灌溉处理间差异明显,将土壤剖面分为0—20,20—80cm上、下2个层次,总体上总有机碳含量上层为渗灌沟灌滴灌,下层滴灌沟灌渗灌;腐殖酸含量上层滴灌沟灌渗灌,下层为渗灌滴灌沟灌;胡敏素上层为沟灌滴灌渗灌,下层为渗灌滴灌沟灌。滴灌处理既能使0—40cm土层土壤有机碳含量保持较高水平,土壤腐殖质含量又高于沟灌、渗灌处理,这对于提升设施土壤肥力水平、保证番茄养分供应是有利的。     

Nitrogen metabolism disorder in watermelon leaf caused by fusaric acid

The effect of fusaric acid (FA) on the activity of leaf nitrogen (N) metabolism enzymes in watermelon seedlings supplied with different N forms was studied. The results showed that FA inhibited nitrogen uptake and caused decreased leaf amide and protein but increased the content of ammonium and amino acids. When treated with FA the activities of enzymes in the pathway for the synthesis of amino acid in leaves (GS, GOGAT, and GDH) were decreased by 15–23%, 13–40%, and 71–86%, respectively. The activity of asparagine synthetase was decreased by 34–57%. The proteinase activity was initially increased by 37–125% at 12 h after treatment of FA but then subsequently decreased. The activity of glutamate-pyruvate aminotransferase was increased by 280–400%, though the activity of glutamate-oxaloacetate aminotransferase was decreased by 30–63%. It was suggested that FA inhibited the uptake of ammonium in seedlings and suppressed the activities of amino acid and amide synthases, while stimulating proteinase activity.A new pathogenic mechanism of watermelon infection by Fusarium spp. was found as FA caused the complete disorder and collapse of the host plant's nitrogen metabolism. This work provides a new insight into the progression of watermelon wilting caused by Fusarium oxysporum f.sp. niveum.