核桃凋落叶浸提液对一年生黑麦草和白花草木樨种子萌发及幼苗生长的化感效应

Allelopathic effects of Juglans regia leaf litter extract on seed germination and seedling growth of Lolium multiflorum and Melilotus albus

【目的】研究核桃(Juglans regia)凋落叶浸提液对一年生黑麦草和白花草木樨种子萌发及幼苗生长化感效应,为林草建植提供理论依据,有利于核桃经济林可持续发展。【方法】以一年生黑麦草(Lolium multiflorum)和白花草木樨(Melilotus albus)作为研究受体,设置不同浓度核桃凋落叶浸提液,分析核桃凋落叶浸提液对豆禾牧草种子萌发及幼苗生长的影响。【结果】1)高浓度核桃凋落叶浸提液显著降低了一年生黑麦草的发芽率和发芽势,且随着浸提液浓度的增高,一年生黑麦草的发芽速率显著降低;随着浸提液浓度的增高,白花草木樨的发芽势和发芽速率呈先升高后降低趋势,发芽时间缩短;2)核桃凋落叶浸提液降低了白花草木樨幼苗叶绿素含量;中等浓度下一年生黑麦草的根系活力显著增加;3)高浓度下一年生黑麦草幼苗抗氧化酶活性显著降低;白花草木樨幼苗过氧化氢酶活性随浸提液浓度的增加呈先升高后下降的趋势。【结论】核桃凋落叶对豆禾牧草种子萌发及幼苗生长化感作用显著,林下建植牧草应充分考虑核桃凋落叶所产生的化感物质对所选草种的影响。

【Objective】The study of the allelopathic effect of Juglans regia leaf litter extract on seed germination and seedling growth of Lolium multiflorum and Melilotus albus grass provides a theoretical basis for forest and grass planting in northern Shaanxi,and is conducive to the sustainable development of J.regia economic forest.【Method】This study L.multiflorum and M.albusas were used as research receptors,and different concentrations of J.regia fallen leaf extracts were set up to analyze the effects of J.regia fallen leaf extracts on seed germination and seedling growth of legume grass.【Result】(1)High concentration of J.regia leaf litter extract had a significant inhibitory ef-fect on the germination rate and germination potential of L.multiflorum,and with the increase of extract concentra-tion,the germination rate of L.multiflorum significantly decreased.As the concentration of the extract increased,the germination potential and germination rate of M.albus showed a trend of first increasing and then decreasing,and the germination time decreases.(2)The extraction solution of J.regia withered leaves reduced the chlorophyll content of M.albus and osmanthus seedlings.While at moderate concentrations,under the influence of the extraction solution of J.regia withered leaves,the root activity of L.multiflorum significantly increased.(3)The antioxidant enzyme activ-ity of L.multiflorum seedlings was significantly reduced under high concentration.The catalase activity in the seed-lings of M.albusincreased first increased and then decreased with the increase of extract concentration.【Conclusion】J.regia leaf litter had a significant effect on seed germination and seedling growth of soybean grass,and the effects of allelochemicals produced by J.regia leaf litter on the selected grass species should be fully considered when planting grass in the underforest.