Year: 1972
Type: article
Abstract: 1. The studies presented here were undertaken to determine the effects of manganese in the nutrient solution and of the defoliation of old leaves on 1-year-old shoots, on the dry weight and manganese contents in each old part which had been produced before the treatments.2. Thirty, 18-month-old Satsuma orange trees on trifoliate orange rootstocks were transferred to the greenhouse on early of November 1966, and grown in the nutrient solution lacking minor elements. On the 11th in January, 1967, when the growth of the flush started, the trees were cut to 3 shoots and allowed to grow until the treatments were started. On the 20th in May, just before the growth of the second flush started, uniform 24 plants were selected and divided into four groups. Treatments consisted of containing (+) or lacking (-) manganese in the nutrient solution in combination with defoliating or non-defoliating their old leaves. Four trees having new good flushes were harvested from each treatment on the 12th in July and were separated into each part and analyzed total manganese contents.3. No differences numbers of new leaves on a plant were found, but dry weights of new leaves were reduced by the defoliating of old leaves, resulting in small leaves, compared with the non-defoliating of old leaves.4. Manganese concentrations of new leaves from plants lacking their old leaves were higher significantly than those of plants having their old leaves in both manganese treatments.5. Excluding the fine roots, manganese concentrations and absolute manganese contents in the old parts reduced greatly in the non-defoliated plants than the defoliated plants in the minus manganese treatment. While in the plus manganese treatment, absolute manganese contents were higher in almost all parts of the non-defoliated plants than those of the defoliated plants.6. Above results suggested that the manganes was redistributed from old parts to newly developing parts in Satsuma orange trees grown under manganese stress, and that the manganese concentrations of newly developed parts were influenced by the growth ratio of new parts to old parts. In contrast, under adequate manganese, manganese in the newly developing parts was occupied with newly absorbed manganese as a result of continued distribution rather than redistribution.7. These confirm the facts in the above field observations.
DOI: 10.2503/jjshs.41.233
Authors: Ryosuke OGATA, Takato TAMADA
Institution: The University of Tokyo
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W2616194546