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Protoplast fusion was induced between sainfoin and alfalfa by an improved polyethyleneglycol (PEG) method. The intergeneric somatic calluses were selected based on complementation of hydroxyproline-resistance of sainfoin and hormone autonomy growth of alfalfa transformation cell line. 17 somatic hybrid plantlets were regenerat-ed. PEG could induce the tight agglutination of protoplasts. During diluting and washing process, cyclization of the linked membrane and formation of vesicle-like structures were observed, resulting in protoplast fusion. 5%-10% glycerol supplemented in the fusion inducing solution markedly increased the frequency of heterogeneous fusion. Better fusion results were obtained when mixed protoplast suspension was dripped in petri dishes in which PEG solution was previously placed. Chromosome number of regenerated hybrid buds varied from 30 to 60. The genome of hybrids in-cluded the small chromosome from sainfoin and two chromosomes with two clear constrictions from alfalfa. The hybrid 相似文献
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根际试验研究表明,水分、有机质、土壤酸度是影响白浆土磷素生物有效性的重要因子。调节土壤水分含量,能增强土壤中铁、铝磷酸盐的溶解,加速磷酸根离子从根际土壤向非根际土壤扩散。增加土壤有机质含量,降低了土壤对P素的吸附自由能(K值),提高土壤中的速效磷含量。适量施用石灰,调节白浆土酸度,由于化学溶解作用的影响,促进了土壤中铁、铝磷酸盐的溶解,增强了土壤中磷素的生物有效性. 相似文献
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双氰胺对碳酸氢铵在土壤中氮素转化的影响 总被引:23,自引:2,他引:21
采用室内培养试验方法,研究了双氰胺对碳酸氢铵中的铵态氮在土壤中动态变化的影响。结果表明,无论是碳铵与双氰胺的机械混施,还是含双氰胺的长效碳铵,在抑制铵态氮硝化产生硝态氮的同时对氨挥发也有一定的抑制作用,使土壤在更长的时间内保持更高的铵态氮含量,并对碳铵施入后土壤的酸碱化强度起到了缓冲作用。添加双氰胺不但提高了碳铵的氮肥利用率,还减少了肥料氮素损失. 相似文献
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白浆土-植物系统营养物质转化机制及其有效性研究Ⅳ.环境条件对土壤磷素有效性的影响 总被引:1,自引:0,他引:1
根际试验研究表明,水分、有机质、土壤酸度是影响白浆土磷素生物有效性的重要因子.调节土壤水分含量,能增强土壤中铁、铝磷酸盐的溶解,加速磷酸根离子从根际土壤向非根际土壤扩散.增加土壤有机质含量,降低了土壤对P素的吸附自由能(K值),提高土壤中的速效磷含量.适量施用石灰,调节白浆土酸度,由于化学溶解作用的影响,促进了土壤中铁、铝磷酸盐的溶解,增强了土壤中磷素的生物有效性. 相似文献
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采用根盒试验研究了施用紫花苜蓿腐解物对白浆土-小麦根际P素形态转化、有效性及小麦植株P素吸收的影响.结果表明,施用有机物料使土壤有效磷显著上升,铝磷、铁磷含量也显著升高,且培养时间越长,效果越明显.小麦植株含P量明显上升,且与非根际土壤铝磷、铁磷的变化显著相关. 相似文献
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连作障碍与根际微生态研究Ⅲ.土壤酚酸物质及其生物学效应 总被引:66,自引:8,他引:58
以黑龙江省大豆重茬 5年与正茬土壤和根系为主要研究对象 ,采用高效液相色谱法 ,研究土壤和根系浸提液中的酚酸物质的含量及其生物学效应 .结果表明 ,重茬土壤中对羟基苯甲酸和香草酸的含量 (1mol·L-1NaOH提取 )大于正茬土壤 ,且差异达到极显著水平 ,香草醛含量差异不显著 ;重茬大豆根系水提液中对羟基苯甲酸、香草酸、阿魏酸、香草醛、香豆素含量均高于正茬 .大豆连作条件下土壤多酚氧化酶活性高于正茬土壤 .重茬大豆根系水提液及在水培条件下外加对羟基苯甲酸对大豆幼苗生长发育有一定的抑制作用 ;酚酸物质加入土壤 1周后 ,对羟基苯甲酸、香草酸、香草醛、阿魏酸、苯甲酸、香豆素残留率分别为 10 .4%、15 .3 %、4.1%、2 .3 %、5 .0 %、17.5 % ;且外加酚酸浓度与土壤中真菌数量呈极显著指数相关 . 相似文献
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利用32P同位素示踪法对白浆土中P肥利用率进行了研究.结果表明,在岗地白浆土上,表层土壤表现出一定程度的供P不足现象,白浆层土壤有效P含量严重缺乏.表层土壤中当季P肥利用率的变幅范围为6.09~12.35%,白浆层土壤P肥利用率为13%左右.施用有机肥能明显提高白浆土OlsenP的含量,加速土壤本身P的活化,各种有机物中,以猪粪对土壤潜在P的活化效果最好.将OlsenP与X值、A值比较,认为OlsenP是评价白浆上P肥力简便易行的可靠指标. 相似文献
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Surface esterification of corn starch films: Reaction with dodecenyl succinic anhydride 总被引:4,自引:0,他引:4
Surface of corn starch films was modified through esterification using dodecenyl succinic anhydride (DDSA) as reactant. The effects of reaction temperature and time, concentration of alkaline aqueous solution for activating starch, concentration of ethanol diluted DDSA, and time of alkaline aqueous solution treatment on the physical properties related to material’s hydrophilic nature, such as moisture absorption and surface water contact angle, were investigated. It was found that the surface esterification modification significantly reduced the moisture sensitivity and surface hydrophilic character of starch film. Due to the hydroxyl groups in the film surface layer were reacted with DDSA, the equilibrium moisture content of the starch film under 95% RH declined 22% and the surface water contact angle increased up to 82% after surface esterification modification. 相似文献