日本生態学会誌
Online ISSN : 2424-127X
Print ISSN : 0021-5007
ISSN-L : 0021-5007
19 巻 , 4 号
選択された号の論文の13件中1~13を表示しています
  • 原稿種別: 表紙
    1969 年 19 巻 4 号 p. Cover1-
    発行日: 1969/08/01
    公開日: 2017/04/11
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  • 原稿種別: 表紙
    1969 年 19 巻 4 号 p. Cover2-
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
  • 原稿種別: 付録等
    1969 年 19 巻 4 号 p. App1-
    発行日: 1969/08/01
    公開日: 2017/04/11
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  • 中村 央
    原稿種別: 本文
    1969 年 19 巻 4 号 p. 127-131
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
    Living adults or beans infested by the weevil, Callosobruchus chinensis, were collected at different localities in the northern area of its distribution, (Fig. 1,Table 1). The weevils collected from the field were reared at one pair and 32 pairs per 10gr. of the beans generated under the conditions of 30℃, 75% R.H., and illumination of 16hr. photoperiod. The activity of the adult was measured by flight intensity stimulated by light, using the apparatus devised by NAKAMURA (1966), and two types, active and sluggish, were grouped separately. Among all local C. chinensis examined there was no remarkable difference regarding the duration of the preimaginal period at the constant temperature of 20,25,27.5,30℃ and humidity of 75% R.H., the number of eggs per female of the active type, the effect of the larval density on the percentage of the emergence of sluggish type, and the relation of the number of eggs laid to the value of Is, in the distribution of eggs laid per bean (Table 2,Fig. 2,3,4). Conspicuous differences among them were however, found in the adult activity, and the number of eggs per female in the sluggish type. It was not clear whether the number of eggs per female in the sluggish type tended to increase from the southern to the northern localities (Fig. 5). However, we can say that the increase of the population density over a certain level may be necessary to produce the active type of this weevil (Fig. 3) since the relation of the larval density to the percentage of the emergence of the sluggish type was almost the same at any locality. The photoperiod also exerted its effect on the percentage of the emergence of the active type (Table 3). From these reasons, therefore, we can infer that in the whole range of the distribution, the active adults emerge during the growth-period of the bean plants, and in the local C. chinensis in which the number of generations in a year is high the number of eggs per female is small, though in the local C. chinensis in which the number of generations per year is low the relations may be the reverse.
  • 金光 桂二
    原稿種別: 本文
    1969 年 19 巻 4 号 p. 131-137
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
    東京大学愛知演習林内に点在する若いクロマツ造林地において, マツヅアカシンムシとその天敵昆虫の生息数を調査した。生息密度の測定は毎年2月頃実施し, 1962〜1967年の間継統した。どの地点においてもマツヅアカシンムシの生息密度は1964年にピークに達し, その後減少した。寄主と天敵の両者の生息数の年変動をみると, 寄生であるマツヅアカシンムシの多い年には天敵も多く, またマツヅアカシンムシの少ない年には天敵も少なかった。天敵昆虫の大部分は寄生蜂であったが, それらのすべてについて寄生率が測定されなかったので, 2月の時点における寄生昆虫と寄主の生息比をもってそれぞれの天敵の働らきの度合いを比かくした。その結果, 天敵昆虫の中では, 単寄生で年1世代を経過し, マツヅアカシンムシを唯一の寄主とするLissonota evetriaeが生息密度も高く, また寄主の生息数の変化に対して最も強力に作用していることがわかった。これに反してPediobius sp.は, 多寄生で年に数世代を経過し, しかもマツヅアカシンムシ以外の多くの昆虫にも寄生し比かく的生息密度が高かったにもかかわらず, マツヅアカシンムシの生息数の変化に対応した働らきが全くみとめられなかった。
  • 佳山 良正, 吉田 穣治, 坂井田 智治
    原稿種別: 本文
    1969 年 19 巻 4 号 p. 137-147
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
    この報告は1966年8月に久住, 阿蘇高原で行なった調査成績をまとめたもので, 主として微地形とススキ共同体の生産力との関係について述べた。久住の調査地は大分県種畜場の敷地内で, 事務所の北西にある牧草地の端より広がるススキーササ型草地であって。久住山頂に向って1,210mの間に8plotを設定し, 土壌断面とススキ共同体の構造との関係を検討した。阿蘇の場合は, 大観峰より西へ3kmの地点で, 阿蘇連峰に向って南東に傾斜する草地について172mの間について調査した。久住の場合は2-4°の傾斜で上向しており, その間に2つの小谷を有す。plot 4(深さ12.48m)plot 6(深さ4.84m)がそれで, いずれも草量が大で, とくにplot 4は3,283g/m^2で, 平坦地の2〜8倍に達していた。そしてススキは大形多年になり, 大形多年生草本が優占し, ネザサは著しく減少した。これに対して平坦地はネザサが優占しているが草高は遥かに低い。阿蘇の場合は, 低地のplot 1を起点にするとplot 3は26.3mの高所に位置する。そしてススキ, トダシバ, ネザサは傾斜を上向するほど草高が低くなり, ネザサは単位面積当り個体数の増加を示した。この草高の矮小化は放牧していない点などより, 常時吹き上げる強風の影響も土壌要因に加わっているものと考えられる。土壌断面を比較するといずれも腐植層が厚いが, 現存量の多い個所は, かなり下層まで土壌水分が豊富である。しかし土壌水分と空気との比率も問題になると思われた。また窒素やリン酸が量的に似たような地区間では, むしろ置かん性の塩基の量が大きく生産性に影響を与えるようで, とくにカリなどは大きな要因になっていると思われる。
  • 新山 恒雄, 沼田 真
    原稿種別: 本文
    1969 年 19 巻 4 号 p. 147-154
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
    In the previous papers (NUMATA and NIIYAMA 1953,NIIYAMA and NUMATA 1962), the authors found the existence of a critical time of weeding for cultivating the upland rice Oryza sativa var. terrestris (Norin No. 24), and a beneficial effect of weeds before the critical weeding time on the crop yield. This study is aimed at the further analysis of such beneficial effects of weeds on a crop. The field experiments were done according to the randomized block method with three repetitions, that is, Blocks : I, II, and III ; Sowing density treatments : A (5cm intervals), B (10cm intervals), and C (15cm intervals) ; and Weeding treatments : 1 (weed-free), 2 (no weeding during 5 weeks after sowing and thereafter weed-free), and 3 (no weeding during 7 weeks after sowing and thereafter weed-free). Here, 5 weeks after sowing is the maximum allowable period for weeds without decreasing the crop yield (NIIYAMA and NUMATA 1962). The plot size is 80×80cm and is divided into four squares (Fig. 1). The weed community in the experimental field is dominated by Digitaria adscendens and Th-D_4-R_5 type (Table 1). The growth of the weeds is, in genera, extremely depressed in the lowest density plots, C (Tables 3,6). The coverage of the weeds after June 19th is in the order of B>A>C. This fact suggests an optimum density of a crop for weed growth (Table 6). An extreme depression in the height growth of the weeds in C may not be caused by an effect of slender growth like in flax weeds and the extreme depression in the height growth of the upland rice on May 3rd be caused by a negative effect of the weeds growing longer over the critical weeding time. However, the recovery of crop growth in C3 is marked where a kind of crop-protective effect of weeds can be seen. Meanwhile, the dominant weed, Digitaria adscendens grows the most numerous adventitious roots on aboveground nodes in C. This may be a kind of adaptation in the growth form (Tables 4,5). Digitaria adscendens and Chenopodium album also grow best in C (Table 7). The distribution of the coverage of the weeds was most homogeneous on July 3rd in every plot (Fig. 2). The distribution of the weeds in a farmland comes, in general, to be most homogeneous in several weeks after sowing, through intraspecific and interspecific density regulation (NUMATA and SUZUKI 1958). The weeds affect the height growth and the number of heads of the upland rice in proportion to its sowing density (Tables 10,12). The growth of the upland rice becomes better after weeding in proportion to the lowering of density, particularly in C, and SDR (the summed dominance ratio) of the upland rice is larger in 2 than in 1 after August 7th (Table 13). The order of the heading time is contrary to the order of C>B>A in the plant height and the number of leaves of the upland rice in 3. This may be a kind of hunger phenomena. The crop yield in 2 and 3 increases as the density lowers (II in Table 15), and particularly the yield in C2 is larger than in C1. The total yield per plot indicates the tendency of 1>2>3 in A, but 2>1 in B and C. From the above-mentioned facts, the allowable limit of weeds (allowable quantity and critical weeding time) to a crop may be closely related with an interspecific density effect.
  • 石井 孝
    原稿種別: 本文
    1969 年 19 巻 4 号 p. 155-167
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
    Morphological comparisons are made among the fourth instar larvae collected from various habitats in the northern parts of Japan. The characters used for comparison are as follows ; the number of the siphonal hair tufts (siphona hair types), siphonal index, siphonal length, siphonal width, head width, numbers of comb scales and pecten teeth, and setae of the first siphonal hair tuft. From the comparison of the siphonal hair type and siphonal index, it is concluded that morphologically different larvae can be obtained from ecologically different habitats, even though they are geographically located close to each other. Some of the morphological differences are considered to be genetical based on the results reported in the previous papers. Summarizing the results reported by various authors, there is a tendency that the siphonal index and the number of the siphonal hair tufts decrease in Culex vagans, Culex pipiens pallens (and C. p. pipiens), C. p. molestus, to C. p. fatigans in this order (however, the order is not definite between C. p. pallens and C. p. molestus). Based on the siphonal index and siphonal hair type, there were C. vagans-like, C. p. pallens-like, C. p. molestus-like, C. p. pipiens-like, and C. p. fatigans-like larvae in the larval populations observed and reported in this paper, although much discussion is needed before the subspecies names can be given to corresponding individuals mentioned above. The morphology of the adult stage should also be included to the identification. It is of interest that morphologically different larvae can be obtained from various ecologically different habitats located close to each other. The Culex pipiens group of Japan is considered to be composed of genetically different strains (or subspecies). Therefore, much pertinent study is needed before concluding that the group is a hybrid population between C. p. pipiens and C. p. fatigans or it is composed of Culex pipiens pallens.
  • 山本 護太郎
    原稿種別: 本文
    1969 年 19 巻 4 号 p. 167-
    発行日: 1969/08/01
    公開日: 2017/04/11
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  • 原稿種別: 付録等
    1969 年 19 巻 4 号 p. 168-
    発行日: 1969/08/01
    公開日: 2017/04/11
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  • 原稿種別: 付録等
    1969 年 19 巻 4 号 p. App2-
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
  • 原稿種別: 表紙
    1969 年 19 巻 4 号 p. Cover3-
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
  • 原稿種別: 表紙
    1969 年 19 巻 4 号 p. Cover4-
    発行日: 1969/08/01
    公開日: 2017/04/11
    ジャーナル フリー
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