摘要
[目的]分析云南松Pinus yunnanensis不同苗龄平茬后苗木根系形态特征,为选择适宜平茬苗龄提供依据.[方法]以 6、10、14、18、30月龄的云南松苗木为材料,统一留茬高度(5 cm)进行平茬,分别在平茬后 60、120、180、240、300、360、420、480 d测定苗木根系形态特征及生物量,分析云南松不同苗龄苗木平茬后的根系构型.[结果]不同苗龄平茬对云南松苗木根系形态特征有显著影响(P＜0.05).在平茬后 480 d时,6月龄平茬的苗木根平均直径(0.825 mm)、根体积(4.435 cm3)比 30月龄平茬的苗木根平均直径(1.302 mm)、根体积(16.282 cm3)小,但总根长较大;6～30月龄平茬苗木的比根长整体呈降低趋势,且 6月龄平茬苗木根比表面积、根组织密度、根细度均显著大于其余苗龄平茬的苗木(P＜0.05),且表现为随着苗龄增加而减小的生长趋势.根平均直径、根体积与根生物量的生长速率没有显著差异,总根长、根表面积与根生物量之间表现为随着苗龄增大生长速率逐渐降低的趋势.[结论]苗龄较小的苗木构建了更细更密集的根系,有利于对水分和养分的吸收利用;苗龄为 6个月的苗木平茬效果较好.图 2表 5 参 40
Abstract
[Objective]This study aims to analyze root morphological characteristics of Pinus yunnanensis seedlings after stumping at different ages,and to provide evidence for selecting suitable stump-age.[method]Taking P.yunnanensis seedlings aged 6,10,14,18 and 30 months as materials,all seedlings were pruned to a uniform height of 5 cm.The root morphology and biomass were measured at 60,120,180,240,300,360,420,and 480 d after stumping,and the root structure of different seedling ages of P.yunnanensis after stumping was analyzed.[Result]Stumping at different seedling ages significantly affected the root morphological characteristics of P.yunnanensis seedlings(P＜0.05).At 480 days after stumping,the seedlings stumped at 6 months had smaller average root diameter(0.825 mm)and root volume(4.435 cm3)compared with those stumped at 30 months,which had an average root diameter of 1.302 mm and root volume of 16.282 cm3,but the total root length was larger.The specific root length for 6 to 30-month-old stumped seedlings showed a decreasing tendency,and the root specific surface area,root tissue density,and root fineness of the seedlings stumped at 6 months were significantly greater than those of the seedlings stumped at other ages(P＜0.05),showing a decreasing trend with increasing seedling age.There was no significant difference in the growth rate of average root diameter,root volume,and root biomass,while total root length,root surface area,and root biomass showed a trend of decreasing growth rate with increasing seedling age.[Conclusion]Younger seedlings build finer and denser root systems,which is conducive to the absorption and utilization of water and nutrients.The seedlings aged 6 months showed the best effect of stumping.[Ch,2 fig.5 tab.40 ref.]
基金项目
云南省农业联合专项重点项目(202301BD070001-152)
云南省农业联合专项面上项目(202301BD070001-035)
云南省万人计划青年拔尖人才项目(YNWR-QNBJ-2019-075)
国家自然科学基金(32360381)
云南省研究生导师团队建设项目(2022-97)
国家科技期刊平台
NSTL
万方数据