煅烧牡蛎壳粉对土壤酸化及琯溪蜜柚果实的改善效果

Improvement Effect on Acidic Soil and the Quality of Guanxi Pomelo by Calcined Oyster Shell Powder

以煅烧牡蛎壳粉为试验材料,对种植琯溪蜜柚的酸性土壤进行为期1年的田间跟踪试验,并对果实品质的改善效果进行研究。采用4个施用量组:0(对照组CK),1.25(T1组),2.50(T2组),3.75 kg/棵(T3组),1次施用后每隔3个月对土壤样本进行pH值、容重、有机质含量的检测。蜜柚成熟后进行糖酸比、固酸比、维生素C含量、汁胞硬度和感官评价试验。扫描电子显微镜观测发现,牡蛎壳煅烧后微孔结构明显增多,且孔径大小介于2~10μm。施用煅烧牡蛎壳粉后,土壤pH值和有机质整体呈现先增加后降低的趋势,容重值呈现逐渐降低的趋势。随着煅烧牡蛎壳粉施用量的增多,果实的糖酸比、固酸比、汁胞硬度值逐渐增大(T3>T2>T1>CK),维生素C含量先升高后稳定。T3组的土壤pH值增加效果最显著(P<0.01),从(3.23±0.13)提高到(4.62±0.46),提高1.39个单位;T2组的土壤容重值降低最显著(P<0.01),从1.34 g/cm 3降低到1.11 g/cm 3,降低17.16%。施用6个月后,T1组的土壤有机质含量显著增加(P<0.05),从初始值14.42 g/kg提高至27.21 g/kg,增加了168.24%。对果实的分析发现,T3组糖酸比和固酸比的改善效果最明显,但差异不显著,与对照组相比分别提高26.14%和18.04%;该组果实的汁胞硬度最低,比对照组降低了37.36%,存在极显著差异(P<0.01);T2组果实的维生素C含量最高,较对照组增加2.21%,存在显著性差异(P<0.05)。以上结果表明,煅烧牡蛎壳粉能够显著改良土壤酸性,改善土壤板结现象,增加土壤有机质含量,同时提高了琯溪蜜柚果实品质和口感。

In this study,calcined oyster shell powder was used to improve the fruit quality of Guanxi pomelo by repairing the acidic soil.Four application groups of 0 kg/tree(CK),1.25 kg/tree(T1),2.50 kg/tree(T2) and 3.75 kg/tree(T3) were designed.Soil samples were collected every 3 months to detect pH value,bulk density and organic content.Guanxi pomelo fruit samples were collected at the mature harvest stage to conduct experiments on sugar-acid ratio,solid-acid ratio,vitamin C content,hardness and sensory evaluation.The calcined and uncalcined oyster shells were observed by SEM.The result showed that the microporous structure of calcined oyster shell increased significantly with pore sizes between 2-10 μm.After the application of calcined oyster shell powder,the soil pH value and organic matter present a trend of first increasing and then decreasing,and the bulk density value presents a trend of gradually decreasing.Guanxi pomelo fruit’s sugar-acid ratio,solid-acid ratio and hardness value present a trend of gradually increasing,and the vitamin C content presents a trend of first increasing and then stabilizing.The soil pH value in T3 increased from(3.23±0.13)to(4.62±0.46),with 1.39 units increment.The bulk density value of soil in T2 decreased most significantly from 1.34 g/cm^2 to 1.11 g/cm^3,a decrease of 17.16%.After 6 months of application,the soil organic matter content in T1 increased from 14.42 g/kg to 27.21 g/kg,with an increment of 168.24%.Compared with the CK,T3 revealed the most significant improvement effect on sugar-acid ratio and solid-acid ratio,which increased by 26.14% and 18.04%,respectively,its hardness of T3 was the lowest,which was 37.36% lower than that of CK.The T2 had the highest vitamin C content,which increased by 2.21% compared with the CK.The results indicated that calcined oyster shell powder could neutralize soil acidity,improve soil consolidation,increase soil organic matter content,as well as the quality and taste of Guanxi pomelo.