雀稗属无融合生殖研究进展

雀稗属(Paspalum)为禾本科黍亚科多年生或一年生植物,是黍亚科内最有经济价值的类群之一。雀稗属植物种群极其复杂,大多数为多倍体。由于多倍体的存在及有性生殖的自交不亲和等原因,雀稗属植物表现出复杂多样的生殖特性,是禾本科中具备无融合生殖特性种类最多的属。对雀稗属无融合生殖的分布、无融合生殖相关的细胞学和胚胎学基础、无融合生殖的特点及其遗传学和分子生物学研究进展进行了综述。     

国产稗属植物的细胞学研究

对国产７种（含变种）稗属Ｅｃｈｉｎｏｃｈｌｏａ植物的细胞学进行了初步研究。９个供试材料的体细胞分别表现两种染色体数目２ｎ为３６或５４。除光头稗Ｅ．ｃｏｌｏｎｕｍＬ外,分析了其余种的核型,其结果为：稗Ｅ．ｃｒｕｓ．ｖａｒ．ｃｒｕｓｇａｌｌｉ２ｎ＝５４＝５８ｍ＋６ｓｍ;西来稗Ｅ．ｃｒｕｓ．ｖａｒ．ｚｅｌａｙｅｎｓｉｓ（Ｈ．Ｂ．Ｋ．）Ｈｉｔｃｈｃ ２ｎ＝５４＝４２ｍ（２ＳＡＴ）＋１２ｓｍ（４ＳＡＴ）;     

东喜马拉雅地区雀稗属一新种

西藏雀稗 新种 图1Paspalum xizangenseB. S. Sun et H. Sun sp. nov. Figure 1Species P. vaginato Sw. affinis, sed culmis caespitosis erectis vel ascendentibus, lematibus inferoribus sparsim villosis deffert.Caespitose perennial. Culms 20-40 cm, erect or ascending. Sheaths glabrous, ligule about 0.5 mm; blades 3-10 cm long, 3-6 mm wide, glabrous. Inflorescence of 2-3 racemes arranged digitately,raceme 3-6 cm, glabrous, with narrowly singed rhachis. Spikelets 2-2.3 mm, solitary, seesile, in 2-ro…     

雀稗属花粉形态及其多萌发孔现象

在广东广泛收集禾本科雀稗属的基础上,观察了雀稗属（Paspalum)9个种及其类群的花粉形态。其花粉一般为球型,平均直径在34－50um之间,花粉表面纹饰一般为疣状突起或皱波状。在四倍体的台湾雀稗（P.formosanum),双穗雀稗（P.paspaloides),雀稗（P.thunbergii),两耳草（P.conjugatum),圆果雀稗（P.orbiculare),长叶雀稗（P.longifolium)和一个十倍体的南雀稗（P.commersonii)的一个类群上发现了禾本科罕见的花粉多萌发孔现象。     

鳗鲡繁殖生物学研究——Ⅲ．鳗鲡性腺发育组织学和细胞学研究

鳗鲡精巢发育可划分为6个时期,即精原细胞前增殖期,精原细胞后增殖期,精母细胞生长、成熟期,精子开始出现期,精子完全成熟期和精子退化吸收期。卵细胞的发育可划分为6个时相,即卵原细胞时相,卵母细胞单层滤泡时相,卵母细胞出现脂肪泡时相,卵母细胞卵黄充满时相,卵母细胞核极化时相和卵母细胞退化时相。以卵细胞发育6个时相在卵巢中组成的差异,也可把卵巢划分为相应的6个时期。对鳗鲡性腺发育的分期,卵黄积累方式,产卵类型等问题进行了讨论。     

国产12种乌头属和18种翠雀属植物的细胞学研究

研究了12种乌头属Aconitum L．和18种翠雀属Delphinium L．植物的染色体。在12种乌头属植物中,除粗花乌头A．crassiflorum为四倍体(2n=4x=32)外,其他种类都为二倍体(2n=2x＝16),中甸乌头 A.piepunense中有B染色体存在,牛扁亚属Aconitum subgen．Lycoctonum的二倍体植物与乌头亚属Aconitum subgen．Aconitum 植物的染色体在大小和形态上有明显区别;所有18种翠雀属植物都为二倍体(2n＝2x=16),其染色体在大小和形态上极为相似,但与乌头亚属的染色体易于区别。翠雀属植物的核型不对称性程度明显高于乌头属植物,因此从染色体证据来看,翠雀属要比乌头属进化。     

长尾雀繁殖生态的研究

长尾雀在长白山为留鸟,是典型的“素食”瘪类,仅在育雏期有很少的动物性食物。繁殖期在筑巢适宜生境１．３对／ｈｍ＾２,冬季在繁殖期相同生境为０．０７４只／ｈｍ＾２．４月初开始有求偶追逐和争雌行为。５月下旬产卵。孵化期１２－１３ｄ．６日龄喂雏３５次／ｄ。６日龄喂雏３５次／ｄ,雏鸟在１０日龄后体温恒定,育雏期１３－１４ｄ。９月中旬后幼鸟换成成鸟羽色。     

黄鳝繁殖生物学的观察

根据黄鳝Monopterus albus的解剖及调查资料,就繁殖生物学方面作了阐述。     

中国稗属一新种(英文)

Echinochloa persistentia Z. S. Diao, sp. nov. Haec species nova spieulis ommino persistentibus numquam deciduis a congeneribus diversa. Gramen annuum, caespitosum, culmi erecti, c. 40—120 cm alti, 1—4 mm in diam.; foliorum vaginae glabrae, laminae anguste linearcs, planae, 10—50 cm longac, 6—12 mm latae, scabrae, ad marginem in crassata, viridulos, spinulosis.     

翠雀属一新变型

本文发表了翠雀属一新变型,即白花翠雀Delphinium grandiflorm L.f.album T.J.Feng et J.X.Huang.     

Recombination indices in species of Erythrina L. (Leguminosae, Papilionoideae)

Darlington's recombination indices were calculated for eight species of Erythina by adding the mean chiasma frequency and the haploid chromosome number of each species. The recombination indices distinguished subgenus Erythraster (two species with greater mean chiasma frequency) from subgenera Micropteryx and Eythrina. This discrimination corroborates literature data on pollen morphology. It was not possible to separate groups at sectional level using recombination index. The recombination indices were also compared with data on breeding system and pollinators, available in literature, to investigate Grant's hypothesis on the occurrence of compensatory mechanisms in the regulation of recombination in plants. The data on breeding systems in Eythrina are very incomplete and it was not possible to correlate values of recombination indices with autogamy or allogamy. Species visited by hummingbirds showed lower recombination indices than species visited by other kind of pollinators.     

Karyology and reproductive biology of Muscari matritensis M. Ruíz Rejón et al. (Liliaceae)

VALDÉS, B. & DÍAZ LIFANTE, Z., 1992. Karyology and reproductive biology of Muscari matritensis M. Ruíz Rejón et al. (Liliaceae). Muscari matritensis M. Ruíz Rejón et al. , previously known from only five localities, has been recorded for S.W. Spain. The plants have a karyotype composition which differs from the other four karyotypes described for this species, and experimental studies of the breeding system provide evidence that they are moderately autogamous.     

大血藤生殖生物学研究

通过野外观测、实验室分析以及人工套袋授粉等方法,研究了大血藤的繁育系统、开花习性、传粉方式以及花粉-胚珠比等生殖生物学特征.结果表明,大血藤的花为单性花,雌雄同株.雄花单花花期为7~10 d,雌花单花花期为2~3 d,种群开花历时14~17 d,散粉高峰期为4月11~17日,属风媒传粉植物.大血藤花粉-胚珠比为600±20,属兼性异交类型,人工套袋实验进一步证明,大血藤的交配系统为兼性异交类型,但以异交为主.     

Aspects of reproduction and diet of the long-finned herring, Ilisha africana, off Cape Coast, Ghana

I. Africana off Cape Coast bred continuously throughout the year. The major breeding season was preceded by a period of high feeding activity, mainly on fish fry, penaeid shrimps and crustacean zooplankton.     

Biotic versus abiotic pollination in Oeceoclades maculata (Lindl.) Lindl. (Orchidaceae)

Geographical variation in the reproductive biology of widespread species often occurs at their distributional boundaries. We sought to determine whether such variation has occurred in an invasive orchid, Oeceoclades maculata, across its naturalized range. We compared its reproductive biology in a Brazilian population with that published for a population on the Caribbean island of Puerto Rico. In the state of São Paulo, O. maculata flowers between December and February, at the height of the rainy season. Similar fruit sets were observed in manual self (76%) and cross (70.4%) pollination treatments. The fruit set of plants protected from both pollinators and rainfall was 6.1%, whereas plants exposed only to rainfall had a fruit set of 41.4%, slightly less than the controls (48.3%). Like the Puerto Rico population, reproduction is primarily through rain‐assisted autogamy, but unlike observations made on the island, outcrossing can eventually occur. We observed two butterfly species (Heliconius ethilla narcaea and Heliconius erato phyllis) pollinating O. maculata. Secretory epidermal cells and trichomes of the spur lumen produced 0.7 µL of 25% (sucrose equivalents) nectar per flower each morning, which was stored in a dilated basal portion of the spur and reabsorbed by the afternoon. Thus, geographical variation in reproductive biology exists across the broad invasive range of O. maculata.     

Reproductive biology of Trichocentrum pumilum: an orchid pollinated by oil-collecting bees

The reproductive biology, reward production and pollination mechanism of Trichocentrum pumilum were studied in a gallery forest in the interior of the State of São Paulo, southeast Brazil. The floral visitors and pollination mechanism were recorded, and experimental pollinations were carried out in order to determine the breeding system of this species. Trichocentrum pumilum blooms in spring. Each paniculate inflorescence bears an average of 85 flowers that present a central yellow callus and finger‐like trichomes on the lateral lobes of the lip. A lipoidal substance is produced and stored among these trichomes. In the studied population, T. pumilum is exclusively visited and pollinated by two bee species (Tetrapedia diversipes and Lophopedia nigrispinis). Pollinaria are deposited on mouthparts of bees during collection of the lipoidal substance from the lateral lobes of the labellum. Trichocentrum pumilum is self‐incompatible and pollinator‐limited. Natural fruit set was low (9%, compared to 45% in experimentally cross‐pollinated flowers). Potentially viable seed exceed 97% in fruits obtained through cross‐pollination and in natural conditions (open pollination).