@article{oai:kpu.repo.nii.ac.jp:00005170,
 author = {齋藤, 秀樹 and Saito, Hideki and 今井, 英行 and Imai, Hideyuki and 中口, 努 and Nakaguchi, Tsutomu and 久後, 地平 and Kugo, Chihei and 川瀬, 博隆 and Kawase, Hirotaka and 竹岡, 政治 and Takeoka, Masaji},
 journal = {京都府立大學學術報告. 農學, The scientific reports of Kyoto Prefectural University. Agriculture},
 month = {Nov},
 note = {林分1ha当りの生殖器官各部分の生産量(乾重と個数)について, ミズナラの若齢Y林分と老齢O林分とを比較し, 種子生産に関係する要因を考察した。各部分の生産量はトラップ法で測定し, 花粉については開花前の雄花序試料に含まれる花粉量と林分の開花雄花序数を掛けて求めた。調査は若齢林が3年間, 老齢林は5年間行った。主な知見は次の通りである。(1) 落果は多く, 8月末で80&acd;90%に達した。これは同化物質の節約になる。(2) 雄花序1個当りに含まれる花粉量は年によって9.3&acd;16mgと0.8&acd;1.2×(10)^6個の範囲にあった。(3) 乾物生産量(kg/ha・yr)は次の通りである(左側が若齢林, 右が老齢林。括弧内は平均値)。開花雄花序(花粉なし) : 7.7&acd;38.5(20.1);17.8&acd;55.9(42.2)。花粉だけ : 11&acd;43(26);24&acd;78(61)。雌性部分 : 81.7&acd;544.4(244.2);25.7&acd;256.4(158.8)。生殖器官合計 : 100&acd;625(291);68.0&acd;379(262)。(4) 各部分の乾物生産量の年次変動は3&acd;10倍(最大値/最小値)であった。しかし老齢林では, 連続4年間の雄花生産の変動は小さく(1.3倍), これはアカマツ林の場合に似ていた。(5) 雄性部分の乾物生産量が生殖器官全体に占める割合は, 若齢林が20%前後, 老齢林では種子豊作年に30&acd;40%で, 凶作年には60%前後を示した。(6) 花粉の乾物生産量は, 開花雄花序(花粉をのぞいた残り)より数%&acd;10%多い。(7) 花粉粒の生産量(個/ha・yr)を求めると若齢林が1.2&acd;5.3(平均2.9)×(10)^<12>, 老齢林2.8&acd;7.9(同5.2)×(10)^<12>となった。この最大値はスギ, ヒノキのそれより少ない。しかし, ミズナラの年次変動はこの2樹種より小さい。老齢林の値はアカマツ林にほぼ一致している。(8) 雄花序, 花粉粒, (総)雄花の個数生産量の年次変動は大きかったが, 雌花に対する雄花序及び花粉粒の数比は2倍以内の小さな変化であった。雌花1個に対して放出された花粉粒は若齢林が1.3&acd;2.4×(10)^6個, 老齢林1.9&acd;4.3×(10)^6個である。既報の2老齢林を加えた比較から, 林分によって雄花対雌花の比率に著しい偏りがあり, これは林齢と無関係であった。(9) 種子の豊作年には結実率が高かった。結実率の上昇は, 巨視的には放出される花粉粒の多少に関係がありそうである。これは将来, 解明しなければならない問題である。, A comparison was made of young (Stand Y) and old (Stand O) stands of Quercus mongolica FISCH. var. grosseserrata REHD. et WILS. with regard to the production rates of each reproductive organ component, and the factors affecting seed production were discussed. Annual production rates (by dry weight and number) per 1-ha stand for each reproductive component except pollen were determined using ten litter traps (each 50cm×50cm in mouth area), while for pollen, this was done together with measurement of the amount of pollen (dry weight and grains) contained in catkin samples before anther opening. The study was conducted for three years in a young stand and for five years in an old stand. The results were as follows. 1) Rates of fruit drop were high, attaining 80-90% of the total number of female flowers by the end of August. This was thought to save photosynthates. 2) The mean amount of pollen in one catkin sample ranged from 9.3 to 16mg (dry weight), and from 0.8×(10)^6 to 1.2×(10)^6 grains. 3) Dry-matter production rates (kg/ha・yr) were as follows (figures on the left are for the young stand and those on the right the old stand. Figures in parentheses represent the average). Open male catkins excluding pollen : 7.7-38.5 (20.1) 17.8-55.9 (42.2). pollen only : 11-43 (26); 24-78 (61). Female parts : 81.7-544.4 (244.2); 25.7-256.4 (158.8). Total reproductive parts : 100-625 (291); 68.0-379 (262). 4) Annual fluctuations in dry-matter production of each reproductive component were 3-10-fold, expressed as the ratio of the maximum to minimum value. However, for production of male parts in the old stand, a slight fluctuation of 1.3-fold during four consecutive years was recognized, which coincided approximately with that of a Pinus densiflora stand. 5) The proportion of male to total reproductive parts in terms of dry-matter production was about 20% for the young stand, whereas for the old stand, it ranged from 30% to 40% in a year of abundant seed crop and was about 60% for a poor crop. 6) Pollen production rates in terms of dry weight were several percent to 10% higher than that of open male catkins (residue). 7) Pollen production rates (grains/ha・yr) were estimated to be 1.2-5.3 (mean : 2.9)×(10)^<12> for the young stand, and 2.8-7.9 (5.2)×(10)^<12> for the old stand. The maximum value was lower than that for Cryptomeria japonica and Chamaecyparis obtusa stands. The range of pollen production in the old stand agreed approximately with that in a Pinus densiflora stand. 8) Small annual fluctuations of less than two-fold were found for the numerical proportions of male catkins or pollen grains to total female flowers, while fluctuations in the numerical production of male catkins, pollen grains and total female flowers were large. The number of pollen grains dispersed into the air for one male flower amounted to 1.3-2.4×(10)^6 grains in the young stand and 1.9-4.3×(10)^6 in the old stand. Judging from the 12 data/years for four stands, added to four sets of data for two old stands reported previously, some stands have high ratios of male to female flowers, and others have low ratios, with no relation to stand age. 9) The seed-maturing ratio or the numerical ratio of apparently sound acorns to total female flowers was high in a year of abundant seed crop. Generally speaking, an increase in the seed-maturing ratio can be related to high pollen production.},
 pages = {46--58},
 title = {林齢の異るミズナラ林における雄花, 花粉, 雌花及び種子生産の比較(林学部門)},
 volume = {41},
 year = {1989},
 yomi = {サイトウ, ヒデキ and イマイ, ヒデユキ and ナカグチ, ツトム and クゴ, チヘイ and カワセ, ヒロタカ and タケオカ, マサジ}
}