缺素条件下枸杞植株生长及营养元素吸收利用互作效应

Interaction effects of absorption between different elements and plant growth of Goji(Lycium barbarum L.)under nutrient deficiency

探究不同营养元素缺乏对枸杞生长发育和营养元素吸收利用的影响,为枸杞缺素诊断与合理施肥提供理论依据。以“宁杞10号”为研究对象,采用营养液培养法,设置全素(CK)、缺氮(-N)、缺磷(-P)、缺钾(-K)、缺钙(-Ca)、缺镁(-Mg)、缺铁(-Fe)、缺锰(-Mn)、缺铜(-Cu)、缺锌(-Zn)和缺硼(-B)11个处理,对枸杞生物量、根冠比、叶绿素、分枝数、营养元素和组分含量进行了测定。结果表明:(1)缺素条件下,枸杞生长普遍受到不同程度地抑制,植株茎叶和根系生物量、叶绿素SPAD值均显著降低,其中-N和-Fe处理对枸杞生长影响最大,且缺素症状明显;生物量、分枝数、SPAD值之间呈正相关关系,与根冠比呈负相关关系;(2)各缺素处理枸杞叶片和根系相应元素含量极显著降低,且对其他营养元素也存在不同影响,不同植物营养元素之间协同或拮抗作用的关联性呈现出“不对称性相关”;(3)缺素条件下,植株叶片的淀粉含量普遍增加,而粗脂肪含量整体呈下降趋势,粗纤维、可溶性糖和灰分含量无明显变化。由此可见,在缺素情况下,枸杞可通过调控自身光合产物的分配比例,或通过调节其他元素的吸收利用效率来激发相应元素的吸收潜力,从而在一定程度上减轻缺素造成的生长抑制;但在长期缺素胁迫下,枸杞表现出明显的缺素症状且生长受到严重抑制。由于枸杞对不同营养元素的吸收利用呈现“不对称性相关”,因此,在枸杞生长过程中应注重元素均衡供应和按需调控。

The Goji variety“Ningqi No.10”was taken as the research object to study the effects of nutrient element deficiency on the growth of plant and the absorption of elements.Total 11 different nutrient deficiency treatments were carried out by hydroponic culture experiment,which were deficiency nitrogen(-N),phosphorus(-P),potassium(-K),calcium(-Ca),magnesium(-Mg),iron(-Fe),manganese(-Mn),Copper(-Cu),zinc(-Zn),boron(-B)and full-nutrient solution(CK).After the culture experiment,the biomass,root-shoot ratio,chlorophyll content,branch number,nutrient element content and plant component content of Goji were investigated.The results showed that:(1)The growth of Goji plant was inhibited in different degrees under the condition of deficient elements.The plant stem and leaf biomass,root biomass and chlorophyll SPAD value decreased significantly compared with the control.The growth inhibition degree of plants were the most obvious and the root-shoot ratio were significantly higher than that of others in the-N and-Fe treatments.Correlation analysis showed that biomass,branch number and SPAD value were positively correlated,but they were negatively correlated with root-shoot ratio.(2)The nutrient deficiency treatment significantly reduced the content of the corresponding nutrient element,and also had different effects on the absorption of other nutrient elements.From the analysis of absorption promotion and inhibition effects,it could be seen that the correlation between different plant nutrient elements presented as“asymmetric correlation”.(3)The effects of different element deficiency treatments on the content of components in plant leaves showed different trends,in which the starch content generally increased,and the change of crude fiber content was different,while the fat content generally was decreased.The content of soluble sugar and ash in leaves was not significantly affected by element deficiency.In conclusion,under the condition of hormone deficiency,Goji can stimulate the absorption potential of corresponding elements by regulating the distribution ratio of photosynthates or adjusting the absorption and utilization efficiency of other elements,so as to alleviate the growth inhibition caused by nutritional deficiency to a certain extent.However,under longterm nutrient deficiency stress,Goji showed obvious deficiency symptoms and its growth was severely inhibited.It is essential to pay attention to the balanced supply of elements and on-demand regulation during the growth of Goji plant for the obvious“asymmetric correlation”.