Zhou Xin, Feng Gai-Li, Li Zhi-Hong, Liu Shu-Xia, Zhao Sheng, Li Yan, Wei Min
College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an 271018, Shandong, China.
Scientific Observing and Experimental Station of Environment Controlled Agricultural Engineering in Huang-Huai-Hai Region, Ministry of Agriculture and Rural Affairs, Tai'an 271018, Shandong, China.
Ying Yong Sheng Tai Xue Bao. 2020 Feb;31(2):501-507. doi: 10.13287/j.1001-9332.202002.023.
To elucidate the mechanism of bloom formation on fruit surface of cucumber, we investigated silicon absorption and bloom formation on fruit surface of cucumber with 'Shannong No. 5' (Cucumis sativus) as scion, 'Yunnan figleaf gourd' (Cucurbita ficifolia, weak de-blooming ability) and 'Huangchenggen No. 2' (C. moschata, strong de-blooming ability) as rootstocks in solar greenhouse at winter-spring and autumn-winter growing seasons. Experimental conditions inclu-ded: T with temperature 28 ℃/18 ℃ (day/night), relative humidity 55%/65%, photosynthetic photon flux density 600 μmol·m·s, and T with temperature 22 ℃/12 ℃ (day/night), relative humidity 85%/95%, photosynthetic photon flux density 300 μmol·m·s. We examined environmental effects on silicon absorption and expression of silicon transporter genes in. The amount of bloom on cucumber fruit surface at winter-spring growing season dramatically increased compared with autumn-winter season. 'Yunnan figleaf gourd' grafted cucumber was more heavily affected by the cultivation season than self-rooted and 'Huangchenggen No. 2' grafted cucumber. In the same cultivation season, 'Yunnan figleaf gourd' grafted cucumber had the highest amount of bloom on fruit surface and silicon content, while own-rooted and 'Huangchenggen No. 2' grafted cucumber had the medium and least amount of bloom and silicon content. Silicon content in each organ and expression of silicon transporter genes in cucumber leaves and roots under T environment were significantly increased compared with T. 'Yunnan figleaf gourd' grafted cucumber had the highest contents of silicon in each organ and expression of silicon transporter genes in leaves in the same environment, followed by own-rooted and 'Huangchenggen No. 2' grafted cucumber. In conclusion, environmental conditions affect absorption and allocation of silicon in cucumber plants, with conseuqnece on bloom formation on fruit surface. Suitable environmental conditions, including temperature, humidity and light, are beneficial to reduce the bloom formation on cucumber fruit surface. High temperature, strong light, and low humidity will increase bloom amount on cucumber fruit. Rootstocks have significant effects on silicon absorption and fruit bloom formation of grafted cucumber.
为阐明黄瓜果实表面蜡粉形成的机制，我们以‘山农5号’（黄瓜）为接穗，‘云南黑籽南瓜’（西葫芦，去蜡粉能力弱）和‘黄城根2号’（南瓜，去蜡粉能力强）为砧木，在冬春和秋冬生长季的日光温室中研究了黄瓜果实表面硅吸收和蜡粉形成情况。试验条件包括：T1温度为28℃/18℃（昼/夜），相对湿度为55%/65%，光合有效辐射通量密度为600 μmol·m·s，以及T2温度为22℃/12℃（昼/夜），相对湿度为85%/95%，光合有效辐射通量密度为300 μmol·m·s。我们研究了环境对硅吸收及硅转运蛋白基因表达的影响。冬春生长季黄瓜果实表面的蜡粉量相比秋冬季节大幅增加。‘云南黑籽南瓜’嫁接黄瓜比自根黄瓜和‘黄城根2号’嫁接黄瓜受栽培季节的影响更大。在同一栽培季节，‘云南黑籽南瓜’嫁接黄瓜果实表面的蜡粉量和硅含量最高，而自根黄瓜和‘黄城根2号’嫁接黄瓜的蜡粉量和硅含量居中且最少。与T2环境相比，T1环境下黄瓜各器官中的硅含量以及叶片和根系中硅转运蛋白基因的表达显著增加。在相同环境下，‘云南黑籽南瓜’嫁接黄瓜各器官中的硅含量以及叶片中硅转运蛋白基因的表达最高，其次是自根黄瓜和‘黄城根2号’嫁接黄瓜。总之，环境条件影响黄瓜植株中硅的吸收和分配，进而影响果实表面蜡粉的形成。适宜的环境条件，包括温度、湿度和光照，有利于减少黄瓜果实表面的蜡粉形成。高温、强光和低湿度会增加黄瓜果实的蜡粉量。砧木对嫁接黄瓜的硅吸收和果实蜡粉形成有显著影响。
