化控对砂糖橘成花数和磷素的影响及相关性分析

Effect of Chemical Treatments on the Number of Flowers and Leaf Phosphorus Content of Citrus reticulate ‘Shatangju’

通过盆栽试验研究干旱胁迫与不同化控技术(多效唑、核苷酸)结合对砂糖橘抽发新梢数、成花数、叶中磷素含量及其关系的影响。结果表明:与对照相比,化控处理均显著抑制砂糖橘抽发的新梢数,但化控处理间差异不显著;与对照相比,化控处理均能诱导砂糖橘成花,但多效唑+干旱胁迫处理(PDSN0)和多效唑+干旱胁迫+50mg/L核苷酸处理(PDSN1)成花数差异不显著,而多效唑+干旱胁迫+100mg/L核苷酸处理(PDSN2)成花数显著小于其它化控处理。叶中磷素含量主要受叶片中磷素含量的制约;在处理前期,除个别处理外,所有化控处理叶中磷素含量均降低,但同一时间内化控处理间差异不显著;在处理后期,多效唑+干旱胁迫和两种浓度的核苷酸在影响叶中磷素含量方面效果相反;在开花前期,各处理叶中磷素含量分别比处理前增加46.15%、30.77%、23.08%和30.77%;在化控处理前期、中期、后期和开花前期,叶中磷素含量与成花数呈显著或极显著负相关。

Citrus reticulate ‘Shatangju’ was pot cultured and treated with combination of both drought and chemicals to determine the impact of the treatments on the number of new shoots and flowers, and leaf phosphorus content. Four treatments were arranged with 3 replications each treatment and 1 pot each replication. The treatments included paclobutrazol＋drought stress（short for PDSN0）, PDSN0 plus nucleotide at 2 concentration levels （short for PDSN1 and PDSN2）, and the control. The correlation between leaf phosphorus content and number of flowers was discussed. The chemical treatments significantly reduced the number of new shoots as compared with the control but there was no obvious difference in the number of new shoots among the chemical treatments. All the chemical treatments induced ‘Shatangju’ to produce flowers. There was no obvious difference in the number of flowers between PDSN0 and PDSN1, and PDSN2 induced a significantly smaller number of flowers than the other 2 chemical treatments. The leaf phosphorus content mainly depended on phosphorus content in leaf blade. At the early stage of treatment the leaf phosphorus content was significantly lower in the chemical treatments than in the control, but not obviously different among the chemical treatments at the same time; at a later stage after treatment nucleotide in PDSN1 and PDSN2 increased the leaf phosphorus content. The four treatments increased the leaf phosphorus content by 46.15%, 30.77%, 23.08% and 30.77% respectively before flowering as compared to those before treatment. The leaf phosphorus content had a negatively or highly negatively significant correlation with the number of flowers at the early, middle and late stages of chemical treatments and before flowering.