‘李光杏’花芽分化时期内源激素及碳氮比值的动态研究

为了明确‘李光杏’花芽分化的时期及分化特点,研究其花芽分化的调控机制,于2018年采用常规石蜡切片方法对花芽分化的时期进行观察,并测定内源激素及碳氮比值的变化。‘李光杏’自6月20日开始至10月初分化完成,其过程分为未分化期、分化初期、萼片分化期、花瓣分化期、雄蕊分化期、雌蕊分化期、花粉细胞期等7个时期,分化盛期集中在8—9月份,且各时期均有重叠现象。6月下旬,随着形态分化开始,ABA、CTK含量下降并维持低水平;IAA含量呈上升趋势,且9月份出现峰值(239 ng·g^-1);ZR、GA含量的变化呈先升后降趋势,9月出现峰值,分别为ZR(64.8 ng·g^-1)、GA(317 ng·g^-1);6月份(未分化期)ABA/IAA、ABA/GA、ZR/IAA比值显著高于其他时期,ZR/GA的变化呈先升后降趋势,7月份出现最高值,为0.25,9月份(雌蕊分化期)最小,为0.21。GA/IAA在6月份最高(1.79),进入形态分化期后逐渐下降。ZR/ABA的变化呈先升后降趋势,9月份最高(0.24)。全氮、全碳含量不断降低,直至1...

Dynamic study on endogenous hormones and C/N ratio during flower|bud differentiation of Li|Guang Apricot

In order to clarify the time and characteristics of flower|bud differentiation of Li|Guang Apricot, and to study the regulation mechanism of flower|bud differentiation, the time of flower|bud differentiation was investigated by conventional paraffin|section method and at the same time, the changes of endogenous hormones and mineral elements were determined in 2018. The differentiation of Li|Guang Apricot was completed from June 20 to the early October. The process was divided into seven stages: undifferentiated stage, early differentiation stage, sepal differentiation stage, petal differentiation stage, stamen differentiation stage, pistil differentiation stage, and pollen cell stage. The peak period of differentiation was concentrated in August-September, and there were overlapping phenomena in all stages. In late June, with the beginning of morphological differentiation, the contents of ABA and CTK decreased and then maintained at a relative low level. The IAA content increased and peaked at 239 ng·g^-1 in September and the ZR and GA values increased first and then decreased, and peaked at 64.8 ng·g^-1 and 317 ng·g^-1, respectively, in September. The ratios of ABA/IAA, ABA/GA, and ZR/IAA in June (undifferentiated stage) were significantly higher than those in other periods. The change of ZR/GA ratio showed a trend of first rising and then declining, with the highest value at 0.25 in July and the smallest value at 0.21 in September (pistil differentiation stage). The GA/IAA ratio peaked at 1.79 in June, and decreased gradually after entering the stage of morphological differentiation. The changes in ZR/ABA ratios showed a trend of rising first and then declining with the highest value at 0.24 in September. The contents of total nitrogen and carbon decreased continuously until the differentiation was completed in October. The C/N ratio increased first and then decreased. The results showed that the significant increase of ABA and CTK and the high ratio of ABA/IAA, ZR/IAA, and ABA/GA (The values were 3.75, 0.41,194, respectively) were beneficial to flower|bud differentiation, and the increase of C/N ratio (37.31~54.79) was also beneficial to flower|organ formation. When the ratio of carbon to nitrogen increased, it was beneficial to flower|bud differentiation of Li|Guang Apricot.