INSEMINATION AND EGG PRODUCTION OF MOUSE-ADAPTED NIPPOSTRONGYLUS BRASILIENSIS (NEMATODA)

Average egg output per individual female Nippostrongylus was increased as the helminth density approached 148 worms per host. After this number, the individual production by females decreased, but was compensated for by the increased helminth density. Egg release, based on fecal recovery, began at 5 days postinfection. The period of maximum egg production occurred earlier with increased numbers of intestinal adults during the preimmune period in the host. A male ratio of 9.1% yielded fecal egg values that were equivalent to the normal levels with 31–44% males in a natural laboratory infection. Immunosuppression of the mouse host revealed cyclic peaks in fecal egg production. The peak intervals were dependent on helminth density, based on worm recovery at 29 days postinfection.

At 105 h after subcutaneous inoculation, 17% of the female N. brasiliensis were inseminated while 81% were mated by 110 h. Intestinal temperature showed no significant effect on female insemination. Examination of intestinal sections also revealed no distinct influence on the time that was required for a 50% insemination level. Observation of egg production by females in vitro showed that 2.2 eggs were released in a ½-h period.     

长江华溪蟹精子形成的研究

1994年9-11月,对采自安徽省宁国县的长江华溪蟹(Sinopotamon yangtsekiense),利用透射电镜技术,并结合细胞化学方法,研究了其精子形成过程。结果显示:早期精细胞圆形,胞质丰富,内含大量内质同小泡及线粒体。核也为圆形,较小。精细胞开始分化,细胞膨胀为长椭圆形,核质重新分布,分别移向细胞的两端。精子的顶体由高尔基体产生,其过程为:高尔基体分泌产生囊泡,继而形成原顶体囊,进一步发育成顶体囊,最后形成顶体。在顶体囊与核之间有膜复合体。中心粒位于核内面凹陷处。细胞化学反应显示,核杯为Feulgen阳性,顶体为PAS阳性。       

SPERMIOGENESIS IN THE PULMONATE SNAIL, EUHADRA HICKONIS IV. EFFECT OF X-RAYS ON THE SPERMIOGENESIS

When animals were irradiated early in spermiogenesis, i. e. , at the spherical nucleus stage (7), two or more flagella were observed to be formed in many cells at the subsequent stages. Other irradiation effects included the absence of cytoplasmic microtubules at an early stage followed by their excessive production later during formation of the flagellum, the abnormalities in structure of the mitochondrial sheath around the axoneme, and the extremely disordered arrangement of flagellar components. However, the basal body and axoneme showed a normal structure at all stages, and acrosome development appeared to be unaffected by the irradiation.     

不同抗寒力巴西橡胶树生理特性的研究

本文以不同抗寒力的巴西橡胶实生母树、无性系幼树和幼苗等为对象,比较研究它们在越冬期间的生理特性差异。研究结果表明,抗寒性强的橡胶实生母树、无性系幼树和幼苗的枝条和叶片,通常比抗寒性弱者具有较弱的呼吸强度、较低量的水分和还原糖,而含较高量的淀粉、蛋白氮,以及叶片含有较多的束缚水和蔗糖。     

道贝线虫的组织化学研究

道贝线虫肠细胞中的金橙颗粒经组织化学证明含有血红蛋白,同时也证明此线虫没有铁离子的储备,不能合成血红蛋白。作者认为血红蛋白来自其寄主旋螺,其主要功能为储备氧。     

SPERMIOGENESIS IN WILD TYPE AND IN A MALE STERILITY MUTANT OF DROSOPHILA MELANOGASTER

Spermiogenesis in the translocation heterozygote T (1; 2H) 25(20) y l 25/FM6 has been studied with the electron microscope and compared with that in wild type males. It appears that the genetic lesion in the male sterility mutant is associated primarily with a failure in differentiation of the head. In wild type flies, the spermatid nucleus assumes a conchoidal shape; chromatin accumulates along the convex surface. Adjacent to the concave surface a large bundle of microtubules runs parallel to the long axis of the spermatid. A single row of microtubules is juxtaposed against the convex surface of the head. As differentiation proceeds, the nucleus elongates, chromatin condenses, and the nucleus is compacted to a final diameter of about 0.3 µ. In the sterile mutant the spermatid nucleus has an irregular or wedge-shaped profile and no concavity is formed, nor is the bundle of microtubules observed. The row of microtubules, however, is usually present around the periphery. The change from lysine-rich to arginine-rich histone in mature wild type sperm does not occur in the sterile male. The substructure of the axial filament and mitochondrial derivatives, however, are similar to those in wild type.     

中国橡胶树疫霉种的研究*

疫病是我国植胶区的主要病害。近年来,作者从云南西双版纳和广东海南岛的橡胶树和胶园土共分离出57株疫霉菌种。通过分类研究,共鉴定出4个种:恶疫霉 Phytophthoracactorum(Leb.＆ Cohn)Schroeter,辣椒疫霉 P.capsici Leoman,柑桔褐腐疫霉 P.citrophthora(Sm.＆ Sm.)Leonian,和棕榈疫霉 P.palmivora(Butl.)Butler。其中辣椒疫霉是首次在橡胶树上发现。我国橡胶树疫霉的种群结构与东南亚和南亚的有所不同,除棕榈疫霉外,其余3种在东南亚和南亚均未发现。而东南亚常见种:簇囊疫霉(P.botryosa)、橡胶疫霉(P.heveae)和蜜色疫霉(P.meadii),在我国却迄今尚未发现或有待证实。以前报道分离自胶园土壤中的芋疫霉(P.colocasiae),可能系柑桔褐腐疫霉之误。绝大多数分离物经配对培养均可产生性器官:辣椒疫霉的A~1交配型和A~2交配型大致相等;柑桔褐腐疫霉和棕榈疫霉的A~2交配型则明显多于A~1交配型。     

SPERMIOGENESIS IN CANCER CRABS

Spermiogenesis in Cancer crabs was studied by light and electron microscopy. The sperm are aflagellate, and when mature consist primarily of a spherical acrosome surrounded by the nucleus with its short radiating arms. The acrosome forms by a coalescence of periodic acid-Schiff-positive (PAS-positive) vesicles. During spermiogenesis one edge of the acrosomal vesicle invaginates to form a PAS-negative central core. The inner region of the acrosome bounding the core contains basic proteins which are not complexed to nucleic acid. The formation of an elaborate lattice-like complex of fused membranes, principally from membranes of the endoplasmic reticulum, is described. These membranes are later taken into the nucleus and subsequently degenerate. In late spermatids, when most of the cytoplasm is sloughed, the nuclear envelope and the cell membrane apparently fuse to become the limiting boundary over most of the sperm cell. In the mature sperm the chromatin of the nucleus and arms, which is Feulgen-positive, contains no detectable protein. The chromatin filaments appear clumped, branched, and anastomosed; morphologically, they resemble the DNA of bacterial nuclei. Mitochondria are absent or degenerate in mature sperm of Cancer crabs, but the centrioles persist in the nucleoplasm at the base of the acrosome.     

巴西橡胶树乳管分化的超微结构研究

用电子显微镜技术研究了巴西橡胶树(Hevea brasiliensis Mnll.Arg.)幼苗初生乳管分化的早期阶段,着重研究了乳管特有的结构成分的形成。最初可辨认的橡胶粒子出现在细胞质中,直径40—60nm,呈均匀的电子致密体;随着橡胶粒子的增大,粒子的中央区变为电子透明的,而周缘保持有电子致密物质,有时看到充满电子致密物的突起。观察到黄色体(本质为分散的溶酶体液泡)可由内质网膨大形成。在乳管发育过程中出现三种具有不同内含物的黄色体:最初的黄体含有染色很深的呈束状的微纤维,它们随后被含有浅色微纤维的黄色体所代替,成熟乳管的黄色体则含有杂乱的细纤维。在乳管分化初期,乳管细胞中不存在具有特殊结构的 F-w 复合体,只有许多与分生组织中的原质体相同的质体。观察到一些发育异常的乳管,它们似乎停留在发育的早期阶段,而不能继续发育成为典型的成熟乳管。     

中国橡胶树疫霉种的研究

疫病是我国植胶区的主要病害。近年来,作者从云南西双版纳和广东海南岛的橡胶树和胶园土共分离出57株疫霉菌种。通过分类研究,共鉴定出4个种:恶疫霉 Phytophthoracactorum(Leb.＆ Cohn)Schroeter,辣椒疫霉 P.capsici Leoman,柑桔褐腐疫霉 P.citrophthora(Sm.＆ Sm.)Leonian,和棕榈疫霉 P.palmivora(Butl.)Butler。其中辣椒疫霉是首次在橡胶树上发现。我国橡胶树疫霉的种群结构与东南亚和南亚的有所不同,除棕榈疫霉外,其余3种在东南亚和南亚均未发现。而东南亚常见种:簇囊疫霉(P.botryosa)、橡胶疫霉(P.heveae)和蜜色疫霉(P.meadii),在我国却迄今尚未发现或有待证实。以前报道分离自胶园土壤中的芋疫霉(P.colocasiae),可能系柑桔褐腐疫霉之误。绝大多数分离物经配对培养均可产生性器官:辣椒疫霉的A~1交配型和A~2交配型大致相等;柑桔褐腐疫霉和棕榈疫霉的A~2交配型则明显多于A~1交配型。     

树木发育阶段理论及其在橡胶树育种中的应用(综述)

近一个多世纪来,树木发育阶段理论的应用研究取得了令人瞩目的成就,在果树育种,造林,园艺等领域得到广泛应用并取得了巨大的经济效益,与此形成鲜明对比的是,树木发育阶段理论研究的核心内容如发育阶段转变的遗传基础,分子机制等方面的基础研究工作却进展缓慢,对各个阶段的发育特性和利用潜力认识不足,在一定程度上限制了该理论在生产实践中的应用和推广范围,本文就树木发育阶段理论的研究现状,存在问题及在橡胶树育种中的应用等进行了综述和探讨。     

NUCLEAR CHANGES DURING SPERMIOGENESIS IN A PULMONATE SNAIL

Changes in both external form and internal arrangement of nuclear material have been investigated in the differentiation of the sperm of the pulmonate snail, Otala lactea. Sperm head differentiation begins with a flattening of the previously spherical nucleus and a thickening of the nuclear envelope covering the anterior and posterior surfaces of that nucleus. Tail filaments can be seen in the cytoplasm at this time. At a slightly later period the mitochondria begin to form the tail filament sheath and at this time the nucleus begins to elongate in a direction parallel to the future axis of the sperm. At the same time the nuclear material begins to orient itself at right angles to the nuclear surface which lines the pit occupied by the centriole. As nuclear elongation proceeds, this orientation of nuclear substance takes on the appearance of 60 A thick sheets bent in a direction parallel to the sperm axis. Soon the sheets fill the entire nucleus. The nucleus then begins to twist along its axis so that it starts to take on the mature, flame-shaped form. At this time the flat sheets begin to disappear and in the mature sperm head they are no longer visible (see Text-fig. 2 B).     

中国雨蛙精子形成的研究

中国雨蛙的精子形成过程中,细胞核的浓缩经历了５个时期。从第１期进入第２期,染色质纤维增粗并聚集成卷曲的柱状结构。从第２期进入第３期,染色质纤维进一步增粗,细胞核逐渐伸直成柱状。进入第４期,染色质紧密聚集,纤维之间间隙很小。进入第５期,染色质纤维聚集成均匀的致密结构。伴随着染色质的浓缩,核膜数次更新,核内不参与浓缩的物质渐次从核中排出,核中出现一串核泡。顶体在染色质未浓缩之前（第１期）开始分化,由一     

两种蝇类精细胞发育过程中细胞核的变态

本文用透射电子显微镜研究了大头金蝇(hrysomyia megacephala)和肥须亚麻蝇(Parasarcophaga crassipalpis)精细胞发育过程中细胞核的变态过程.精细胞从球形细胞演变为线形精子,核要经历四个时期,即:球核期,细胞为球形,核亦为球形,核膜与一般体细胞核无异;棒核期,核拉长如棒,顶体形成,核膜孔聚集于一侧;染色质凝聚期,染色质与核质分开,经过一系列变化,再凝聚成致密的块状,多余核质从核孔聚集处开口排出核外;成熟期,核变成一团电子密度极大的腊肠形.精细胞抛弃绝大部分细胞质和多余的结构,变成线形精子.以上演变过程两种蝇类完全相似,但在染色质凝聚期的变化中差异却很大:大头金蝇凝聚程序为:细纤维—粗纤维—块状—致密团;肥须亚麻蝇则为:蚁蚕状—纵列薄片状—厚片状—块伙—致密团.     

GENERAL-PURPOSE GENOTYPES FOR HOST SPECIES UTILIZATION IN A NEMATODE PARASITE OF DROSOPHILA

The nematode Howardula aoronymphium parasitizes several species of mushroom-feeding Drosophila. A survey of isofemale strains of H. aoronymphium and a 25-generation selection experiment revealed that this species does not comprise host races, and that it harbors little heritable variation for adaptation to specific hosts No tradeoffs in performance on the different host species were evident. General-purpose genotypes, which can utilize all host species, characterize H. aoronymphium. An important feature of the natural history of these nematodes—correlated epidemiology across host species—is postulated to be both a cause and a consequence of the evolution of general-purpose genotypes in this species.     

ELECTRON MICROSCOPE STUDIES ON SPERM DIFFERENTIATION IN MARINE ANNELID WORMS. II. SPERM FORMATION IN ARENICOLA BRASILIENSIS

The course of spermiogenesis in arenicola brasiliensis was observed with the electron microscope. The spermatogonia floating in the body cavity seem to proliferate and differentiate to mature spermatozoa in the coelomic fluid. More than a hundred spermatids are connected to one large central mass of cytoplasm and spermiogenesis proceeds synchronously in one cluster, which changes into a sperm-disc during maturation. The pre-acrosomal vesicle originates from the Golgi-body and gradually changes into the acrosomal vesicle of peculiar structure like a cup upside down. In the process of differentiation of the acrosome, a part of the material in the acrosomal vesicle is transferred into the space between the vesicle and the nucleus. The posterior one-third of the cylindrical nucleus is surrounded by four middle-piece mitochondria. The flagellar axoneme originates from one of the centrioles, which is located near a posterior pit in the nucleus.     

橡胶树花药和小孢子发生与发育过程的观察

应用石蜡切片法．观察橡胶树的实生树和RRIM600、GT-1品系的花药壁以及小孢子的发生和发育过程,得到如下结果：1．实生树的花药壁通常由四层细胞组成,发育形式为双子叶型。药室内壁细胞在发育后期进行径向条纹加厚．至花药开裂时仍保留着原生质体。中层由一层或不规则的两层细胞组成,在小孢子单核期消失。绒毡层细胞具单棱或双核,属分泌型,至花粉发育到三细胞时消失。小孢子母细胞减数分裂为同时型。成熟花粉粒具三十细胞。精细胞椭圆形,在光镜下不能区分出细胞质鞘和核仁。所观察的实生树雄花,多数发育正常,很少有空秕的花粉。2．RRIMB00品系的花药和小孢子发生与发育和实生树相似,但至后期只有少数花粉发育正常,多数成为大小不等的败育花粉;此外也有一些败育的雄花。3．GT-1的花药在小孢子母细胞减数分裂时,绒毡层细胞的体积开始异常增大并液泡化．小孢子在四分体内解体或分离后成为空秕花粉。