新型复合保水剂对植烟土壤性质及烤烟有机酸含量的影响

Effects of New Compound Water-Retaining Agent on Tobacco-Growing Soil Properties and Organic Acid Content of Flue-Cured Tobacco

本研究采用大田小区试验,以不施保水剂为对照(CK),设置市售保水剂T1、自制聚乙烯醇保水剂(PVA/AA)T2、自制生物炭复合保水剂(PVA/AA/B)T3和自制腐植酸钾复合保水剂(PVA/AA/HAK)T4共5个处理,研究不同类型保水剂对植烟土壤理化性质、烤后烟叶有机酸含量和经济效益的影响。结果表明,T4处理(PVA/AA/HAK保水剂)效果较好,其T3处理次之,土壤理化性状均明显改善,均较对照显著提高烤烟的产量和产值;T4处理全生育期土壤含水率和速效磷、速效钾、碱解氮、有机质含量较CK分别增加16.98%~29.78%、16.44%~18.11%、9.59%~18.08%、15.16%~25.00%、10.45%~15.98%;土壤脲酶、蔗糖酶活性分别提高15.72%~19.93%、10.10%~13.80%。PVA/AA/HAK保水剂显著提高烟叶非挥发性有机酸总量,其中苹果酸、柠檬酸含量较对照分别提高53.68%和68.29%。相关性分析结果表明,烤烟苹果酸含量与土壤碱解氮含量呈显著正相关;草酸含量与土壤脲酶活性呈极显著正相关,与土壤含水率呈显著正相关。综上所述,施用新型生物炭及腐植酸钾复合保水剂明显改善了土壤质量,提高了烟叶非挥发性有机酸总量和经济效益。

To explore the effects of different types of water-retaining agents on soil quality and organic acid of flue-cured tobacco,a plot experiment in field was conducted with commercially available water-retaining agent(T1),self-made polyvinyl alcohol water retaining agent(PVA/AA,T2),self-made biochar composite water-retaining agent(PVA/AA/B,T3),self-made potassium humate compound water-retaining agent(PVA/AA/HAK,T4),and no retaining agent application(CK).The effects of different water-retaining a-gents on the physicochemical properties of tobacco soil,and the organic acid content and economic properties of cured tobacco leaves were investigated.The results showed that T4 treatment had better effect,followed by T3,which obviously improved the soil properties and significantly increased the yield and economic benefit of flue-cured tobacco compared with CK.Compared with CK,T4 treatment increased the soil moisture content,available phosphorus,available potassium,alkali-hydrolyzed nitrogen and organic matter in the whole growth period by 16.98%to 29.78%,16.44%to 18.11%,9.59%to 18.08%,15.16%to 25.00%,and 10.45%to 15.98%,as well as the soil urease and sucrase activities increased by 15.72%to 19.93%and 10.10%to 13.80%,respectively.T4 treatment significantly increased the total amount of non-volatile organic acids in to-bacco leaves,and the contents of malic acid and citric acid were increased by 53.68%and 68.29%compared to CK,respectively.Correlation analysis showed that malic acid content was significantly positively correlated with soil alkali-hydrolyzed nitrogen content;oxalic acid content was very significantly positively correlated with soil moisture content.In conclusion,the application of PAV/AA/HAK water-retaining agent could obviously improve soil quality,and increase the total amount of non-volatile organic acids and economic benefit of tobac-co leaves.