【作者】 邱慧珍；

【导师】 胡恒觉； 张福锁； 黄高宝；

【作者基本信息】 甘肃农业大学 ， 作物栽培学与耕作学， 2003， 博士

【摘要】 本研究采用营养液培养和土壤培养等方法对不同磷效率基因型冬小麦(Triticum aestivum L.)小偃54(Xiaoyan54)和京411(Jing411)等基因型对不同供磷状况(正常供磷、中断供磷、磷肥种类、低磷胁迫)的响应进行了探讨,旨在探明不同磷效率小麦基因型差异的机理,寻求快速有效筛选磷高效基因型小麦的根系和生理指标。结果如下:1.营养液培养试验结果表明,Xiaoyan54和Jing411在正常供磷和中断供磷条件下的根系形态特征和植株生长状况以及对磷的吸收利用具有明显差异。Xiaoyan54在正常供磷条件比Jing411具有更大的根冠比和更理想的根参数,表现在根半径小,根长和比根长值大,因此其根系含磷量、单位根重(根长)吸磷量、比根吸收率和根系磷吸收速率以及植株磷利用效率均显著大于Jing411;根系吸磷量与根长及根重间均具有良好的直线相关,但与根长的决定系数大于与根重的决定系数,用单位根长和单位根重的吸磷量均能表征小麦根系的吸磷量;根表面积与根系鲜重间的决定系数明显大于与根系干重间的决定系数,用根系鲜重为基数计算的根系吸磷量更能反应不同磷效率基因型间的差异。中断供磷强烈抑制了Xiaoyan54和Jing411植株的生长,但对不同磷效率基因型小麦和对植株不同部位的抑制作用明显不同:对Jing411的抑制程度明显大于对Xiaoyan54,对地上部生长的抑制作用显著大于对根系。在中断供磷的第1～3周,Xiaoyan54的地上部和根系干重分别比对照减少了5.3%～41.2%和3.3%～25.1%,Jing411减少了15.3%～54.9%和5.3%～38.4%。中断供磷增大了Xiaoyan54和Jing411的根冠比,强烈抑制了小麦的分蘖,且对Jing411分蘖的抑制程度明显大于对Xiaoyan54。中断供磷显著降低了Xiaoyan54和Jing411幼苗植株地上部和根系的含磷量,促进了小麦对体内磷的有效利用,显著提高了植株地上部的磷利用效率,但显著降低了植株含磷量、吸磷量和磷吸收速率。Xiaoyan54对中断供磷的忍耐能力明显强于Jing411。2.用土培方法研究了两种磷肥(枸溶性钙镁磷肥CMP和水溶性过磷酸钙SSP)和两种非水溶性磷肥活化剂(无机矿物活化剂IA和有机活化剂OA)在石灰性土壤中对不同磷效率小麦苗期生长和基因型差异以及磷效率的影响,结果表明:SSP和CMP对小麦生长的影响无明显差异,但对磷效率的影响显著不同。SSP有利于提高磷吸收效率,CMP有利于提高磷利用效率。施用磷肥可显著增加小麦的地上部干物重,增加的程度因磷肥种类和基因型不同而异。不同磷肥处理的植株磷含量和吸磷量有明显差异,植株磷含量和吸磷量在CMP处理中最低,在CMP+IA处理中最高;无机活化剂IA处理明显促进了小麦对CMP中磷的吸收,并能显著提高土壤的有效磷含量。不同磷效率小麦的植株含磷量和吸磷量存在明显的基因型差异,磷高效基因型的植株含磷量和吸磷量显著高于磷低效基因型;不同磷效率基因型小麦的地上部干重在CMP处理中表现的差异最大,而植株地上部磷含量、地上部吸磷量和地上部磷利用效率以及地上部钙含量均在SSP处理中表现的差异最大。不同磷效更多还原

【Abstract】 The responses of winter wheat genotypes with different phosphorus efficiency (Xiaoyan 54 and Jing 411) and other genetypes to various phosphorus supply (phosphorus sufficiency, phosphorus removal, phosphorus fertilizers and phosphorus deficiency) were investigated in the nutrient solution and the soil pot experiment under the controlled conditions. The main results of the research are as follows:1. There was a significant difference in root morphological features, plant growth, phosphorus uptake and utilization between Xiaoyan 54 and Jing 411 under phosphorus sufficiency and phosphorus removal conditions in the nutrient solution under the controlled conditions. Compared with Jing 411, Xiaoyan54 had greater root/shoot ratio and perfect root parameters, such as smaller root radius; longer root length which might contribute to the efficient phosphorus uptake and utilization, resulting in higher phosphorus content in root, phosphorus uptake per unit root weight and per unit root length, root and shoot ratio, phosphorus adsorption rate, and phosphorus utilization.Both the phosphorus uptake per unit root length and per unit root weight could be used to express the phosphorus uptake of the wheat root, however, the much better linear correlation between phosphorus uptake and root length was found than that between phosphorus uptake and root weight. A much better correlation was also found between root absorbing area and root fresh weight than root dry weight, therefore, the phosphorus uptake on the base of root fresh weight expressed the genotypic difference between wheat genotypes more significantly.The phosphorus removal from the solution has significant constraint to the wheat growth, especially to the shoot growth of the two genotypes, and Jing 411 was more sensitive to phosphorus removal from the solution than Xiaoyan 54, and its shoot and root day weight decreased by 15.3%～54.9% and 5.3%～38.4% respectively during the three weeks of phosphorus removal, which were significantly higher than those of Xiaoyan 54 with the corresponding figures of 5.3%～41.2% and 3.3%～25.1%. The phosphorus removal from the solution increased the root/shoot ratio and the increment of Xiaoyan 54 was much more than that of Jing411, the tillers of the two genotypes were decreased by the phosphorus removal and Jing411 was far more sensitive to the removal.The phosphorus removal from the solution decreased the phosphorus content in plant, phosphorus uptake and phosphorus uptake rate of the two genotypes significantly, but the tolerance to the phosphorus removal of Xiaoyan54 was much stronger than Jing411.2. The effects of different phosphorus fertilizers (super phosphate SSP and calcium magnesium phosphate CMP) and two activators for CMP (inorganic activator IA and organic activator OA) on growth and phosphorus efficiency and genotypic difference of wheat genotypes with different phosphorus efficiency were investigated in the soil pot experiment under the controlled conditions. The results showed that there was no significant difference between SSP and CMP on growth of wheat genotypes更多还原