琯溪蜜柚幼苗几种缺素症的诱导与研究

Induce and Research on the Symptom of Lack of Several Mineral Elements of Guanxi Honey Pomelo Seedling

琯溪蜜柚是我国一个优良的柚类品种,营养诊断是生产中的一个难题.以琯溪蜜柚实生幼苗为材料,在室内溶液培养条件下,诱导琯溪蜜柚幼苗缺乏N、P、K、Ca、Mg、S、Fe的7种缺素症,研究琯溪蜜柚幼苗上述7种缺素症的形态表现特征及各缺素处理对琯溪蜜柚幼苗生长、生物量、功能叶的叶绿素含量的影响.结果表明:各缺素处理都诱导琯溪蜜柚幼苗出现各自特有的专一缺素症状;不同缺素处理诱导琯溪蜜柚幼苗出现不同缺素症的时间和程度有差别,7种缺素症以缺Ca症表现最早,以缺Ca、Fe的症状最为明显,其它五种缺素症状次之、但都可明显觉察;不同缺素处理都影响琯溪蜜柚幼苗生物量,缺素处理的干物质积累量均低于完全培养,缺N、Ca、Mg、Fe处理对干物质积累与对照相比有明显差异,分别为对照的46%、30%、49%、43%;除缺P处理外,其它缺素处理的功能叶的叶绿素含量均明显低于完全营养液培养的植株,其中尤以缺Ca、Mg、Fe为显著,分别为对照的47%、44%、17%.据上述不同必需矿质元素缺素症的表现特征和规律,制作了琯溪蜜柚幼苗上述缺素症的检索表,以供琯溪蜜柚生产中营养诊断与合理施肥借鉴.

Nutrient diagnosis of Guanxi honey pomelo is a problem in production. To investigate the effect of Guanxi honey pomelo which treated with 7 mineral element deficiency by indoor solution culture, the morphological charac- ter, growth, biomass, chlorophyll content of the plant were observed. The results showed that： 1. specific symptom was found in each treatment;2. The time of symptom appearance in each deficiency solution was different, and each had different impacts;The symptom Ca or Fe deficiency was the most obvious;3. The dry mass accumulation of the deficiency solution was lower than that of complete nutrient solution（ CK）, and N, Ca, Mg, Fe deficient treatments were reduced to 46% ,30% ,49% ,43% relatively;4. Except P deficient treatments, the chlorophyll content of the deficiency solution was obviously lower than those of CK, Ca, Mg, Fe deficient treatments which were reduced to 47% ,44% ,17% relatively. Finally, to diagnose and fertilize conveniently, we made the retrieval table of element deficiency symptoms of Guanxi honey pomelo according to these specificity and regularity.