影响南京甜樱桃坐果的关键时期

研究不同生育期的生态条件对甜樱桃花芽分化和坐果的影响,确定导致南京地区(年均温15℃)甜樱桃坐果率低的关键时期,将郑州的一部分4年生盆栽结果甜樱桃运至南京生长1年后,然后将郑州和南京两地的盆栽苗分别在落叶期、休眠结束后进行双向位置交换,采用石蜡切片法观察花芽和胚囊形态发育,并在果实着色期观察坐果率。结果显示:全生育期在郑州、落叶期由郑州运至南京、休眠结束后由郑州运至南京、全生育期在南京、落叶后由南京运至郑州的‘早红宝石’甜樱桃坐果率分别为38.2%、14.7%、12.9%、8.9%和31.7%;无胚囊的比例分别为41.5%、55.6%、57.7%、74.5%和50.0%;全生育期在郑州和落叶后由郑州运至南京休眠结束后再运回郑州的甜樱桃‘萨米脱’的坐果率分别为13.9%和18.8%。结果表明:影响南京地区甜樱桃坐果的关键时期应是春季开花坐果期;而对于一些能满足需冷量的品种,休眠期对坐果率的影响不大;夏季花芽分化期的高温影响花芽分化进程及分化质量。

The Critical Period Affecting Fruit Setting of Sweet Cherry in Nanjing

It was studied that different ecological conditions affected on the flower bud differentiation and fruit setting of sweet cherry to identify the critical period that influences sweet cherry fruit setting in warm regions. First，we transported some potted sweet cherry trees（Prunus avium L.）from Zhengzhou to Nanjing to make them grow for a year，then took the potted trees growing in Zhengzhou and Nanjing as test materials. The treatment included the exchange of trees between Zhengzhou and Nanjing at the stage of leaf fall in winter and before budding in spring. The bud paraffin sections were made to observe the difference on the development of flower bud and embryo sac. The fruit setting rate was investigated at the stage of fruit coloring. The results were as follows：The fruit setting rate of the cultivar‘РубиноваяРанняя’growing in Zhengzhou for whole season，transported from Zhengzhou to Nanjing at the stage of leaf fall，transported from Zhengzhou to Nanjing before budding，growing in Nanjing for whole season，transported from Nanjing to Zhengzhou at the stage of leaf fall was 38.2%，14.7%，12.9%，8.9% and 31.7%；The percentage of the bud that had ovule but no embryo sac was 41.5%，55.6%，57.7%，74.5% and 50.0%，respectively. Fruit setting rate of‘Summit’were that totally growing in Zhengzhou and that transported from Zhengzhou to Nanjing at the stage of leaf fall then transported to Zhengzhou when the dormancy period finished was 13.9% and 18.8%，respectively. These indicated that the blooming and setting stage may be the critical period that leads to low setting rate in warm areas. For some cultivars of low chilling requirement，dormancy period has virtually no effect on fruit setting. The high temperature in summer has little influence on fruit setting during the period of flower bud differentiation but obviously affects the bud development status and quality.