【摘要】 杨梅对硫有较强的吸收能力 ,3年生‘东魁’杨梅定植一年后 ,在未施任何肥料的情况下 ,使土壤含硫量下降了 37 7%。杨梅吸收硫主要积累在叶片和根瘤中 ,叶片和根瘤中的含硫量是根的 2倍左右。杨梅吸收钴主要积累在根瘤和根中 ,根瘤和根中钴含量是叶片的 4 88和 4 4 8倍。每株施硫酸钴 15和30mg能促进杨梅对硫和钴的吸收利用 ,且硫和钴优先向根瘤运输和积累 ;根瘤和叶片含硫量分别是根系含硫量的 3 38～ 4 5 8倍和 2 75～ 3 72倍 ,根瘤含硫量又是叶片含硫量的 1 2 3倍 ;根瘤含钴量分别是根和叶的 1 39～ 1 90倍和 3 5 3～ 4 5 5倍。每株施硫酸钴 15和 30mg ,能显著增加杨梅植株的生物量、株高、根瘤量和固氮酶活性 ,且根瘤的固氮酶活性是对照的 8～ 18 35倍。提出硫元素与Frankia放线菌的共生固氮有关 ,有利于根瘤形成和固氮。更多还原

【Abstract】 Sulphur contents of soil where three years old Myrica rubra trees were planted for one year without the application of fertilizers decreased by 37.7% indicating that there is a stronger capability of S absorption in this plant which is mainly accumulated in leaves and root nodules. It has been observed that sulphur contents in leaves or root nodules is about two times as much as that of roots. That cobalt contents in root nodules and roots are 4.88 and 4.48 times as much as that of leaves respectively showed that cobalt is mainly accumulated in root nodules and roots of M. rubra. Below 30 mg CoSO₄·7H₂O per tree, sulphur or cobalt can be preferentially transported and accumulated into root nodules. Sulphur contents in root nodules and in leaves were 3.38-4.58 times and 2.75-3.72 times as much as that of roots respectively, Moreover sulphur contents in root nodules were 1.23 times as much as that of leaves. Similarly, when CoSO₄·7H₂O below 30 mg per tree was used, cobalt contents in root nodules were 1.39-1.90 and 3.53-4.55 times as much as that of roots and leaves respectively. When CoSO₄·7H₂O below 30 mg per tree was used,biomass, tree height, amount of root nodules and nitrogenase activities of M. rubra were increased remarkably and nitrogenase activities of root nodules in treatment were 8-18.35 times as much as that of control. A hypothesis is put forward that sulphur may have relation to symbiotic nitrogen fixation of Frankia and can promote formation of root nodules and nitrogen fixation.更多还原