机构地区: 华南农业大学园艺学院
出 处: 《植物资源与环境学报》 2004年第1期48-52,共5页
摘 要: 研究了不同长豇豆〔VignaunquiculataW.ssp.sesquipedalis(L.)Verd〕品种幼苗在缺磷胁迫下的形态结构变化。结果表明:缺磷胁迫下,耐缺磷品种'芦花白'的叶片和海绵组织厚度增幅较大,栅栏组织厚度与海绵组织厚度的比值减小,气孔密度增幅较小;茎和茎导管直径增大,且比不耐缺磷的品种'二芦白'大;根直径变小,根量增加,这使其在缺磷胁迫下能保持较强的养分和水分吸收、输导能力和光合能力。缺磷胁迫下,长豇豆叶表皮气孔密度增大,气孔蒸腾加强,促进了水分和磷从根部向上运转及磷的被动吸收。不耐缺磷品种'二芦白'的气孔密度增加幅度较大,促进磷吸收运转的强度较大,为避免过多失水,栅栏组织厚度及栅栏组织与海绵组织厚度的比值增加较大,减弱了非气孔蒸腾的强度。 Changes of seedling anatomical structures of asparagus bean 〔Vigna unquiculata W. ssp. sesquipedalis (L.) Verd〕 cultivars under phosphorus-deficiency stress were studied. Under P-deficiency stress, thickness of leaf and spongy tissue of 'Luhuabai' (High P-deficiency-tolerance) plants increased more than that of 'Erlubai' (Low P-deficiency-tolerance), densities of stomata increased less than 'Erlubai', the ratio of thickness of palisade tissue and thickness of spongy tissue (P/S) decreased, diameter of stem and vessel increased and were larger than 'Erlubai', root diameter decreased but root number increased. Thus there were stronger capability of absorption and translocation of nutrient, water and photosynthesis in 'Luhuabai', then enhanced the tolerance to P-deficiency stress. Under P-deficiency stress, the increase of stoma densities enhanced transpiration, then enhanced translocation of water and phosphorus from root to shoot and passive absorption of phosphorus, that of 'Erlubai' increased more, however, to avoid too much water-loss, thickness of palisade tissue and P/S increased more, thus non-stomata evaporation decreased.