【摘要】 喷布酸式砷酸铅以后可以加强甜橙叶片和果实的生理作用,所以能略为提高果实的重量、糖含量和维生素丙含量,大大减少含酸量。本文并讨论了喷布时期、浓度、次数和方法等问题。更多还原

【Abstract】 The experiment has been made at Wang Jia Peng Orchard of the Citrus research in-stitute in 1963 by fifteen treatments of different concentrations of the lead arsenate solution and in different seasons. After spraying we have studied the physiological functions of the fruits and leaves, and after harvesting analysed the content of sugar, acidity and vitamin C of the fruits. The results are as follows:It may increase the photosynthesis and the respiration of leaves and fruits, afer spray-ing of lead arsenate (PbHAsO4). Hence spraying lead arsenate in suitable concentration, and in suitable time it will effectively improve the quality of sweet orange with the decrease of acidity, increase of sugars and vitamin content, and also the ratio of sugar to acid. It will increase the weight of fruit and promote the vigor of the tree. But when the concentration is too high, the acid decreases very much, the ratio of sugar to acid increases greatly, the fruit becomes smaller, flavour becomes poor and then it will weaken the growth of the tree.It is the best result to spray the sweet orange with 0.25% of lead arsenate three times continually, during the period after the early young fruit dropping and before June drop, while the ratio of sugar to acid rises to 106.4 per cent greater than the Check.更多还原