石灰性土壤磷矿粉直接施用对紫花苜蓿生长的影响

Effect of phosphate rock powder application onalfalfa growth in calcareous soil

摘要:

【目的】 磷矿粉是一种难溶性磷肥，探索磷矿粉在石灰性土壤施用的可能性，以期充分利用我国大量的难溶性磷矿资源。【方法】 以3 个不同品位磷矿粉为磷肥源（PRⅠ、PRⅡ和PRⅢ），以水溶性磷肥过磷酸钙为对照（CK），对3 个紫花苜蓿品种阿尔冈金、陇东苜蓿和金皇后进行了土培盆栽试验，分别测定其株高、叶数、叶绿素含量（SPAD 值）、地上生物量及根系生物量。【结果】 地上生物量干、鲜重均表现出PRⅠ于阿尔冈金苜蓿最高，分别较CK 提高了111. 07% 和98. 09%；根系生物量干、鲜重表现出PRⅡ于陇东苜蓿最高，分别较CK 提高了483. 33% 和502. 97%。PRⅢ于阿尔冈金紫花苜蓿株高较高，较CK 提高了16. 66%，在陇东紫花苜蓿上与CK 基本相同；叶片数施PRⅠ品位磷矿粉于阿尔冈金紫花苜蓿上最多，较CK 提高了57. 07%；叶绿素SPAD 值施PRⅠ磷矿粉于陇东紫花苜蓿上最大，较CK 提高了32. 56%，于阿尔冈金紫花苜蓿上次之，较CK 提高了15. 45%。【结论】 PRⅠ磷矿粉有利于促进紫花苜蓿的生长，陇东紫花苜蓿和阿尔冈金紫花苜蓿对磷矿粉表现出较好的吸收利用能力，金皇后紫花苜蓿的施用效果最差。

Abstract:

【Objective】 This study aimed to evaluate the effects of phosphate rock powder，an insoluble phosphatefertilizer，on the growth of three alfalfa varieties（ Medicago sativa‘ Algonquin’，M. sativa‘ Longdong’，and M.sativa‘ Goldqueen’） in calcareous soil.【Method】 Three grades of phosphate rock powder（ PRⅠ，PRⅡandPRⅢ）were used as phosphate fertilizer sources，while water-soluble phosphate and calcium superphosphate was used asthe control treatments（CK）. A soil pot cultivation experiment on three alfalfa varieties（M. sativa‘ Algonquin’，M. sa-tiva‘ Longdong’ and M. sativa‘ Glodqueen’），was conducted to assess the potential utilization of insoluble phosphate resources in China and application of phosphate powder in calcareous soil. Key parameters measured plantheight，number of leaves，chlorophyll content（SPAD value），and aboveground and root biomass for each alfalfa varietiesunder different phosphorous fertilizer treatments.【Result】 The dry and fresh weight of aboveground biomass ofM. sativa‘ Algonquin’ were highest under PRⅠ，increasing by 111. 07% and 98. 09% respectively，compared toCK. The dry and fresh weights of root biomass of M. sativa‘ Longdong’ were highest under PRⅡ，and increased483. 33%、502. 97% respectively，compared to CK. The plant height of M. sativa‘ Algonquin’ under PRⅢwas thehighest，with a 16. 66% increase compared to CK；however，there was no significant difference between the phosphaterock treatments and CK for M. sativa‘ Longdong’. The number of leaves for M. sativa‘ Algonquinunder’ underPR Ⅰ showed the highest increase，with 57. 07% compared to CK，while the SPAD valuewas highest for M. sa-tiva‘ Longdong’ under PRⅠ，increasing by 32. 56% compared to CK，followed by M. sativa‘ Algonquin’ under PRⅠ ，which increased by 15. 45% compared to CK.【Conclusion】 PRⅠ effectively promoted the growth of alfalfa. M.sativa‘ Longdong’ and‘ Algonquin’ varieties exhibited better absorption and utilization of phosphate rock powder，whereas M. sativa‘ Glodqueen’ responded poorlyto the phosphate treatments in this study.