An embryological study ofPlatanthera bifolia (Orchidaceae)

Flowers ofPlatanthera bifolia were hand-pollinated and fixed in FPA₅₀ after 2, 5, 7, 14, and 21 days. Ovules, made transparent in Herr's clearing fluid, were investigated using confocal scanning laser microscopy. Pollination initiates the megasporogenesis. Two days after pollination dyads are frequent. Three days later most embryo sacs contain two nuclei. Seven days after pollination the embryo sacs are 4–8-nucleate and some are organized, and a week later all embryo sacs are organized and fertilization takes place. The embryo sac development follows thePolygonum type. Twenty-one days after pollination the egg nuclei have been fertilized and the embryo sacs contain 2- to many-celled embryos. A suspensor is formed during early stages of embryo development but degenerates later. Fertilization of the central nucleus does not lead to endosperm development.     

Armillaria jezoensis,a new symbiont ofGaleola septentrionalis (Orchidaceae) in Hokkaido

NineArmillaria isolates obtained from the roots ofGaleola septentrionalis in Hokkaido were identified asA. jezoensis by means of mating tests. Cultures of these isolates were similar in colony morphology, mycelial growth and rhizomorph formation on each of malt extract-dextrose agar (MDA), potato-dextrose agar (PDA), andG. septentrionalis root extractdextrose agar (GDA) media, showing better mycelial growth and rhizomorph formation on GDA medium.     

Pollination ofOphrys (Orchidaceae) in Cyprus

In the southern part of Cyprus the pollinator —Ophrys (Orchidaceae) relationships and its specifity have been investigated from the end of February until the middle of March 1986. 12Ophrys spp. were found. To date, only a single pollinator reference has been reported from this island. We found the following pollinators:Melecta tuberculata (Ophrys kotschyi),Eucera dimidiata (Ophrys flavomarginata),Eucera gaullei (Ophrys umbilicata),Eucera paulusi (Ophrys bornmuelleri),Anthophora erschowi (Ophrys elegans),Andrena torda (Ophrys sicula =O. lutea subsp.minor),Andrena cinereophila (Ophrys fusca, small-flowered),Andrena flavipes (Ophrys israelitica),Andrena morio (Ophrys iricolor andOphrys transhyrcana),Andrena bimaculata (Ophrys sphegodes aggr., probably formerly confused withO. transhyrcana). Most interestingly, it could be verified thatO. flavomarginata/O. umbilicata, O. bornmuelleri/O. levantina andO. transhyrcana/O. sphegodes aggr. (possiblyO. sintenisii) are different biospecies. This is a result of genetic isolation due to varying pollinators, and of differences in flower morphology.     

Observations of the floral biology ofPrasophyllum odoratum (Orchidaceae,Spiranthoideae)

Prasophyllum odoratum is a vernal, nectariferous, terrestrial orchid that flowers profusely six to eight months following cyclical fires that disrupt sclerophyll woodlands. The morphology of the column and pollinarium is indicative of taxa placed within the subfam.Spiranthoideae. The orientation of the pollinaria to the stigma appears to prevent mechanical self-pollination. Both cross- and self-pollination appear to be effected by insects that forage within the brightly-colored, scented, non-resupinate flowers. Ants and drosophilid flies remove nectar, but do not appear to transport pollinaria between flowers. The primary pollinators are polytrophic flies in the fam.Syrphidae and opportunistic male bees in the genusLeioproctus (Colletidae). Approximately 52% of the flowers on a raceme set seed. The comparatively short floral tube ofP. odoratum reflects the dependence of this species on short-tongued insects to effect successful dispersal of pollinaria.     

Floral evolution and phylogeny in the tribeThelymitreae (Orchidaceae: Neottioideae)

The Australian orchid tribeThelymitreae, composed ofCalochilus, Epiblema, andThelymitra, is unique in theOrchidaceae because of the presence of a mitra or staminodal complex. Evidence from floral structure suggests thatEpiblema andThelymitra are sister genera and thatCalochilus is derived from aThelymitra ancestor. A Gene Pool Vortex model and a hypothetical phylogeny illustrate that introgressive hybridization, allopatry, and long distance dispersal have played a major role in the evolution of the tribe. Pollination and hybridization in the tribe are discussed with major emphasis on floral mimicry.     

多叶斑叶兰繁育系统与传粉生物学研究

为探讨多叶斑叶兰(Goodyera folisa)的繁育系统与传粉生物学特征,对其开花物候、花粉活力与柱头可授性、人工授粉、花的挥发性成分以及昆虫传粉行为进行了研究。结果表明,多叶斑叶兰的唇瓣黄色,萼片白色或白色带红褐色;单花花期为(9.4±0.8)d;花粉在开花后第1天具备活力,柱头在开花后第2天具备可授性,花粉活力和柱头可授性都在开花后第5天达到峰值。去雄套袋和不去雄套袋都不能结实,人工自花授粉、同株异花授粉和异株异花授粉的结实率分别为93.3%、95.0%和96.7%,自然结实率为43.3%。花朵的主要挥发性成分为1-辛烯-3-醇、3-辛醇和N,N-二甲基甲酰胺。多叶斑叶兰传粉者为中华蜜蜂(Apis cerana)。多叶斑叶兰具有自交亲和能力,但在自然界不具有主动自交现象,必须依赖中华蜜蜂传粉,花色及花香气味为吸引传粉者的主要因素。     

Evolution,pollination, and systematics of the tribeNeottieae (Orchidaceae)

The various classifications of the orchid tribeNeottieae are reviewed and a new classification is proposed that divides the tribe into three subtribes,Neottiinae, Limodorinae, andCephalantherinae, based primarily on characters of the column (gynostemium). A cladistic analysis illustrates that these three subtribes are more closely related to one another than either is to any other group in subfam.Neottioideae, although there are very few apomorphic characters for the tribe. Pollination biology is also discussed showing links between breeding systems and distribution. There is also a possible role between column and labellum morphology and the emergence of a deceptive pollination syndrome from one of reward.     

Bird pollination in South African species ofSatyrium (Orchidaceae)

Field observations showed that three South African orchid species,Satyrium carneum, S. coriifolium andS. princeps, are pollinated by sunbirds. Foraging sunbirds insert their bills into the labellum chamber of the flowers and suck nectar from the labellum spurs with their tongues. The column overarches the entrance to the labellum and pollinaria become affixed to the upper mandible of the bill. Birds often attempt to remove pollinaria by rubbing their bills against a branch, but are mostly unsuccessful due to the large plate-like viscidia which attach the pollinaria very firmly to the bill. Other modifications for bird pollination in theseSatyrium species may include the red, carmine or orange colour of the flowers, sturdy inflorescence stems used for perching and large amounts of dilute nectar in the spurs. EachSatyrium species was pollinated by several species of sunbird, and despite some differences in flowering time, occasional hybrids occur at a site whereS. carneum andS. coriifolium share the same sunbird pollinators.     

Trapping noctuid moths with synthetic floral volatile lures

Male and female noctuid moths were collected from plastic bucket traps that were baited with different synthetic floral chemicals and placed in peanut fields. Traps baited with phenylacetaldehyde, benzyl acetate, and a blend of phenylacetaldehyde, benzyl acetate, and benzaldehyde collected more soybean looper moths, Pseudoplusia includens (Walker), than benzaldehyde-baited or unbaited traps. Females comprised over 67% of the moths captured and most were mated. At peak capture, over 90 male and female moths per night were collected. In another experiment, phenylacetaldehyde delivered in plastic stoppers attracted more P. includens moths than traps baited using other substrates, but this chemical delivered in wax attracted more velvetbean caterpillar moths (Anticarsia gemmatalis Hübner). Other noctuid male and female moths collected included Agrotis subterranea (F.), Argyrogramma verruca (F.), Helicoverpa zea (Boddie), and several Spodoptera species. Aculeate Hymenoptera were collected in large numbers, especially in traps baited with phenylacetaldehyde delivered from stoppers.     

Insect pollination and floral mechanisms in South African species ofSatyrium (Orchidaceae)

The morphologically diverse flowers in the genusSatyrium reflect adaptations to a wide range of pollinators. Several recently discovered pollination systems inSatyrium are described and illustrated here; these include pollination by solitary bees, carrion flies, butterflies and moths. Two basic types of floral mechanism are recognised inSatyrium: (1) Species pollinated by lepidoptera and birds have long floral spurs and plate-like viscidia seated in lateral rostellum notches; these viscidia become attached to the proboscis or bill of the pollinator. (2) Species pollinated by flies and bees have relatively short floral spurs and globose viscidia seated in terminal rostellum notches; these viscidia become attached to the face, thorax or eyes of the pollinator.     

Pollinator limitation and position dependent fruit set in the high Andean orchidMyrosmodes cochleare (Orchidaceae)

Myrosmodes cochleare is a terrestrial orchid restricted to high elevations of the northern Andes. It is self-compatible but not autogamous. Flowering begins at the apex of the inflorescence, but flower size increases steadily towards the base. Fruit set of selfed flowers was found to increase significantly from the apex to the base of the inflorescence. Open-pollinated fruit set was significantly lower than hand-pollinated fruit set overall, but the highest levels occurred in the middle of the inflorescence. Eumenid wasps and a calliphorid fly were observed to pollinate the flowers, but visits were rare and occurred only during infrequent warm periods.     

The fecundity and long-term variability in abundance of noctuid moths (Lepidoptera,Noctuidae)

Summary The relationship between fecundity and long-term adult fluctuations of 29 temperate noctuid moths was investigated and is explained in terms of the r- and K-selection strategies. The potential population growth rate per year (PGR) and the rate of return to equilibrium (sensu Pimm 1982) have been calculated and correlated with generation-to-generation fluctuations. A highly significant correlation was found between PGR and the coefficient of generation-to-generation variation. The r-strategy species possess the highest PGR, the highest generation-to-generation coefficient of variation and their larvae are polyphagous. Species with typical features of K-strategists exhibit the lowest PGR values and the lowest generation-to-generation coefficients of variation. Their larvae seem to be exclusively oligophagous.     

Pubescence,floral temperature and fecundity in species of Puya (Bromeliaceae) in the Ecuadorian Andes

Summary The effects of inflorescence pubescence on floral temperatures and fecundity were examined in four species of Puya in the Ecuadorian Andes. These species span an elevational range from 1,980–4,000 m and comparisons among these species showed that pubescence production increases significantly with elevation. Flower temperatures of glabrous or slightly pubescent species of Puya from lower elevations closely tracked air temperature, while those of the pubescent páramo species did not. Pubescence removal experiments on Puya hamata, a páramo species, demonstrated that pubescence is an effective insulator, maintaining elevated flower temperatures. In Puya clava-herculis (also a páramo species) elevated flower temperatures were associated with higher seed set. Thus, the greater production of inflorescence pubescence in páramo species of Puya may be an important factor contributing to reproductive success in these higher elevation species.     

Pollination by deceit and floral mimesis inThelymitra antennifera (Orchidaceae)

Thelymitra antennifera is found to be a general mimic of the search image of other co-blooming yellow or cream-flowered species including members of the following genera:Hibbertia, Goodenia and, to a lesser extent,Helichrysum, Pimelia andStackhousia. The most common pollinators areLasioglossum (Chilalictus) spec. and the introducedSyrphus damaster (hover fly) as well as a solitary wasp,Eurys spec.—T. antennifera acts by deceit, involving opticals (yellow colour and pollen imitation) as well as olfactory (sweet odour) signals. Capsule production is low and density dependent, a situation demonstrated in other species which have evolved pollination syndromes involving deceitful mimicry.     

Reproductive systems and crossing potential in three species ofBulbophyllum (Orchidaceae) occurring in Brazilian ‘campo rupestre’ vegetation

Experimental self-, cross- and interspecific pollinations were carried out inBulbophyllum weddellii, B. involutum andB. ipanemense (Orchidaceae). The last two species are closely related, butB. weddellii is somewhat more distant. The three species are self-compatible, with pollination by a vector necessary for fruit formation. In all crossing types, high rates of fruit abortion and formation of seeds without embryos were observed, particularly in interspecific crosses that involvedB. weddellii. Crosses between the more closely relatedB. involutum andB. ipanemense produced fruit formation rates and seed viability similar to those obtained in intraspecific crosses. These results agree with current hypotheses that suggest that interspecific crossing rates reflect phylogenetic proximity. Examination of pollen tube growth and aborted fruits suggests that a series of factors may be involved in the high abortion rate for fruits and large proportion of seeds without embryos. The low interspecific fertility noted forB. weddellii andB. involutum is important in the maintenance of isolation between these species that are sympatric, flower in the same period and share the same pollinators.     

Embryology and systematic position ofLiparis (Orchidaceae)

The embryology ofLiparis paradoxa andL. rostrata has been studied. The young anther wall consists of an epidermis, endothecium, three middle layers and secretory tapetum with uninucleate cells. In the mature anther, two or three sub-epidermal layers develop fibrous thickenings. The anther wall development corresponds to the massive type. Simultaneous cytokinesis results in decussate, isobilateral, linear, T-shaped and tetrahedral pollen tetrads. The pollinia are compact and at anthesis the pollen grains are 2-celled. Ovules are anatropous, bitegmic and tenuinucellate. Both the integuments are dermal in origin and 2-layered. Development of female gametophyte is of the monosporic, 8-nucleate type. Double fertilization occurs. The primary endosperm nucleus degenerates. The mature embryo is organized from the derivatives of tiers 1, 1, m, and n. Its development conforms to a variation of the Onagrad type. The seed coat is formed entirely by the outer layer of the outer integument. There are three sterile and three fertile valves in the ovary. In the prefertilization stages valves consist of parenchymatous cells. After fertilization, the sterile valves become sclerenchymatous whereas the fertile valves remain parenchymatous. The embryological characters support the disputed systematic position ofLiparis within subtribeLiparidinae ofEpidendreae.     

Effect of mating frequency on fecundity and longevity of the predatory mite <Emphasis Type="Italic">Kampimodromus aberrans</Emphasis> (Acari: Phytoseiidae)

The effect of single versus multiple mating on longevity and fecundity as well as the number of matings required to maximize a female’s reproductive success of the predatory mite Kampimodromus aberrans Oudemans were studied under laboratory conditions. Newly emerged adult females of the stock colony of K. aberrans were placed individually on a bean leaf disc, and maintained at 25°C and 16:8 LD. A young male remained with a female for limited periods or continuously. Mating was a requisite for oocyte maturation and oviposition. Females which mated three to four times during their life and females in continuous presence of males, laid significantly and considerably more eggs than single-mated females. Virgin females lived the longest, and those in continuous presence of males the shortest. In all cases and irrespective of the number of matings, the sex ratio of the offspring was male-biased in the first three to four days of oviposition period, and female-biased in later days.     

Floral mimesis inThelymitra nuda (Orchidaceae)

Insect pollination occurred inThelymitra nuda R. Br. on sunny days when the ambient temperature exceeded 20 °C. The flower buds on a raceme opened subsynchronously displaying the brightly-colored, actinomorphic perianth and exposed the contrastingly-colored, scented and ornamented column. InT. nuda the staminodes and the filament of the fertile stamen are fused to one another producing an inflated hood over the anther. This staminodal hood is terminated in two non-ornamental, but brightly-colored, central lobes and two terete lateral lobes bearing approximately 400 white trichomes. Each trichome bears a double chain of 30–40 spherical, rugulose cells. Female bees, in the genusLasioglossum (Halictidae), were observed to land directly on the hood and curled their bodies around the four lobed tip of the staminodal complex. The bees attempted to forage on the lobes as if they were collecting pollen from fertile, poricidal stamens. These bees applied thoracic vibration to the yellowish central lobes and actively scraped the trichome clusters (Pseudopollen) with their forelegs. Bees carried the pollinaria ofT. nuda dorsally on their abdomens. Abdominal contact with the rostellum appeared to occur when the female bee disengaged herself from the staminodal hood. Observations made of bees on co-blooming flowers, and analyses of pollen loads collected by bees suggested that the orchid flower mimics the guild of blue-purple flowers that lack floral nectar but offer pollen in poricidal anthers. The models ofT. nuda are co-bloomingLiliaceae in the generaDichopogon andThysanotus. However, nectarless, buzz-pollinated flowers are also extensively distributed over the orchid’s range. More than 30% of the flowers in theT. nuda population had their pollinaria removed, suggesting a high capacity for cross-pollination in an orchid genus usually considered to be self-pollinated via mechanical autogamy. This study confirmed previous predictions that column modifications represented a trend towards pseudanthery.     

兰科带唇兰属一新异名

经过对标本馆馆藏标本的研究,确认原四川特有的峨眉带唇兰[Tainia emeiensis (K. Y. Lang) Z. H. Tsi]与大花带唇兰(T.macrantha Hook. f.)为同种植物,因此予以归并。     

Mating and fecundity of Dermatophagoides farinae

Studies of the life cycle of cultured Dermatophagoides farinae found that after an initial mating D. farinae females lived for 63.3 ± 64.6 (SD) dafter their egg production period ended .The long period after cessation of egg production for D. farinae suggested D. farinae females could mate multiple times and produce eggs continuously for a longer period. The purpose of this study was to determine if female D. farinae could mate at least two times, and subsequently increase the production of viable eggs over a longer period of time compared to a single mating. Female D. farinae were randomly selected from thriving cultures and isolated in cages. When the females had ceased to lay eggs a male was added to the cage. Fifty-seven percent of the isolated females mated again and produced a second batch of viable eggs. In natural or culture populations, females have continuous availability of males. Therefore, in another experiment, females that emerged from the tritonymphal stages were continuously exposed to fresh males and fecundity and lengths of the reproductive and post reproductive periods were determined. These females had a 11 d longer reproductive period and produced 30.7% more eggs compared to females that only mated one time after they emerged from the tritonymphal stage. However, the post reproductive period was still long (58.6 ± 11.4 [SE] d) the significance of which is not clear. In conclusion, this study revealed that D. farinae females are capable of more than one successful mating that results in increased egg production compared to that of a single mating. It is likely that females mate multiple times in natural and culture populations. It was observed that females actively attract males during the reproductive period but not afterward even though she continues to live a long time. This revised version was published online in July 2006 with corrections to the Cover Date.