椪柑省力化疏花疏果研究

Labor-saving flower and fruit thinning practices in Ponkan

以椪柑(Citrus reticulate Blanco)为试验材料,在不同时期(盛花期、盛花后1周、盛花后2周或第2次生理落果中期)分别喷施不同浓度的石硫合剂、萘乙酸、乙烯利或3,5,6-TPA,探究不同处理的疏花疏果效果。结果表明:盛花期喷施石硫合剂1~3°Bé以及盛花后1周喷施2~3°Bé都有较明显的疏除效果,坐果率只有对照的一半左右;无论是盛花后1周还是2周喷施3种浓度的萘乙酸均可达到显著的疏花疏果效果,坐果率均在6.5%以下;同样,3个不同时期(盛花期、盛花后1周或盛花2周)分别喷施3种浓度的乙烯利,疏除效果亦显著,坐果率均低于5.5%;第2次生理落果中期喷施10mg/L的3,5,6-TPA疏除效果不明显,20、30和40 mg/L的3,5,6-TPA处理则有非常显著的疏花疏果效果,坐果率只有1%左右。以本研究数据作为参考,在生产当中,可根据实际需要选择合适的化学试剂及其喷施时期和浓度,疏除部分花果,达到代替人工疏花疏果、增大果实的目的。

The effects of spraying different concentrations of lime sulphur,naphthylacetic acid(NAA),ethephon or 3,5,6-TPA at different stages(full bloom,one week after full bloom,two weeks after full bloom and the middle of second physiological drop of young fruits)on flower and fruit thinning of Ponkan(Citrus reticulate Blanco)trees were studied.The results showed that spraying lime sulphur 1-3°Béat full bloom and 2-3°Béat one week after full bloom had significant effect on flower and fruit thinning.The fruit setting rate was only about half of the control.Either at one week or two weeks after full bloom,spraying three different concentrations of NAA had significant thinning effect with less than 6.5%fruit setting.Similarly,spraying different concentrations of ethephon at three different stages(full bloom,one week or two weeks after full bloom)had also significant effect on flower and fruit thinning,resulting less than 5.5%fruit set.Spraying 10 mg/L of 3,5,6-TPA at the middle of second physiological drop of young fruits did not have any significant effect on flower and fruit thinning.However,the treatment of 3,5,6-TPA at concentrations of 20,30 and 40 mg/L had more significant effect on thinning,the fruit setting rate was only about 1%.Taking the data of this study as a reference,the appropriate chemical reagents and their spraying period and concentration can be selected according to actual needs in the production,and some flowers and fruits can be eliminated to achieve the purpose of replacing the manual sparsely blooming and fruiting and increasing the fruit size.