土施有机添加剂和硫磺对小白菜生长和养分吸收的影响

通过盆栽试验,研究了土施粗氨基酸、风化煤、L-TRP、L-PHE和硫磺对小白菜干物质积累、叶绿素含量、硝酸盐含量、硝酸还原酶活性(NRA)以及N、P、K、Fe吸收的影响。结果表明,土施风化煤、硫磺以及L-TRP和L-PHE混施可以显著提高小白菜生物量。当风化煤的用量为20g/kg干土时,能显著提高小白菜的叶绿素含量和N的吸收量,改善氮素营养状况。当硫磺的施用量为0.2g/kg干土和0.4g/kg干土时,可使小白菜体内的硝酸盐含量分别比对照降低41.6%和47.4%。供试条件下,硫磺可以提高小白菜对P、K、Fe的吸收,而粗氨基酸、风化煤、L-TRP、L-PHE以及L-TRP和L-PHE混施处理抑制了P、K、Fe的吸收或促进作用不明显。研究结果还表明,土施有机添加剂和硫磺与对照相比,能显著提高小白菜体内的NRA,但是各处理硝酸盐含量与NRA之间不存在显著的相关关系,NRA提高可能是由于植物激素或有机酸和硝酸盐共同作用的结果。

Effects of organic additives and elemental sulphur applied to soils on the growth and nutrient absorption of Brassica chinensis

Pot experiment was conducted to determine effects of rough amino acid, weathered coal,LTRP,L-PHE and elemental sulphur applied to soils on biomass, chlorophyll content,NO~-_3N,NRA and N,P,K,Fe absorption of Brassica chinensis. Results of the pot experiment showed that biomass of Brassica chinensis significantly increased with the application of weathered coal and combined application of L-TRP and L-PHE.It was found that application of weathered coal at rate of 20g/kg soil significantly increased chlorophyll content and N absorption of Brassica chinensis. When the elemental sulphur was applied at rate of 0.2 and 0.4 g/kg soil,NO~-_3-N content in Brassica chinensis was decreased by 41.6% and 47.4%,respectively,compared with check plot.In the experiment condition,P,K,Fe absorption of Brassica chinensis was increased with the application of elemental sulphur,and deceased with the application of rough amino acid,weathered coal,and L-TRP,L-PHE or the combined application.Results also showed that application of the organic additives and elemental sulphur significantly increased the NRA of Brassica chinessis, but no significant correlation was found between NO~-_3-N content and NRA in plants.The increase in NRA may be the result of coordinated effect of phytohormone or organic acid with NO~-_3N in the plant.