Biological Stain Commission Membership,May 1949

Officers

President, H. J. Conn, Box 269, Geneva, N. Y. (representing Society of American Bacteriologists.)

Vice-President, W. F. Windle, University of Pennsylvania, Philadelphia, Pa. Secretary, S. I. Kornhauser, University of Louisville Medical School, Louisville

Ky. Treasurer, E. H. Stotz, University of Rochester, School of Medicine, Rochester

N. Y. (representing American Chemical Society.)     

A morphological revision of the genus Herbertus S.Gray (Herbertaceae,Marchantiophyta) in Africa,including the East African islands

Abstract

The genus Herbertus S.Gray in Africa and the East African islands is revised. The division of the genus into two broad species complexes centred on H. dicranus (Tayl.ex Gottsche et al.) Trev. and H. juniperoideus (Sw.) Grolle is confirmed. H. capensis (Steph.) Sim, H. capillaris (Steph.) H. doggeltianus (Steph.) Demaret, H. lobatus (Steph.) Demaret, H. mascarenicus (Steph.) S.Arn., H. mollis (Steph.) Dusén, H. stuhlmannii (Steph.) Demaret and Schisma kilimandjarense Steph. are synonymous with H. dicranus. H. grossevittatus (Steph.) S.Arn. ex Grolle is synonymous with H. juniperoideus. Three new species are described: H. spicatus N.G.Hodgetts sp. nov., which is related to H. juniperoideus and appears close to the neotropical H. pensilis, with long, narrow leaf lobe apices and a sheathing leaf base; H. mauritianus N.G.Hodgetts sp. nov., also related to H. juniperoideus, has fewer basal slime papillae and the vitta bifurcating lower down; and H. pocsii N.G.Hodgetts sp. nov., which is related to H. dicranus but has setaceous leaf lobe apices composed of long, narrow cells. The relationships of the taxa and patterns of distribution, taking account of recent molecular work, are discussed.     

A small collection of mosses from Himalayan Pakistan

Abstract

Forty moss taxa are listed from the Kaghan Valley, N.W. Himalaya with ecological data; of these nine appear to be unrecorded for Pakistan. Cryptoleptodon rigidulus (Mitt.) Broth. is regarded as an ecotype of C.pluvinii (Brid.) Broth. and is relegated to synonymy under the latter.     

Brassica glabrescens,eine neue Art aus Nordost-Italien

Abstract

The new endemic species Brassica glabrescens Poldini is described from the Friuli, Italy. It is a perennial caespitose hemicryptophyte belonging to sect. Brassicaria (Godr.) Coss. (= Oreobrassica Prantl), which shows close affinity to the very complex species B. repanda (Willd.) DC. and particularly to its subsp. saxatilis (DC.) Heywood from South France.     

Soil aggregate and particulate C and N under corn rotations: responses to management and correlations with yield

Background

Soil aggregate and particulate organic matter (POM) C and N provide valuable insight into C cycling and storage, and are sensitive to management, but effect of these pools on corn yield is unknown.

Methods

Corn yield, N uptake, and aggregate and POM C and N at 0–5, 5–25 and 25–50 cm were measured and correlated in continuous corn (Zea mays L.) (CC), strip-till corn/soybean [Glycine max (L.) Merr.] (CS), and organically managed corn/soybean/wheat (Triticum aestivum L.) with green manure (CSW).

Results

The POM differed only at 0–5 cm, where greater POM mass was found in CS than CC and CSW. Lower POM-C and POM-N was found in CSW than CC and CS. Overall, CSW had fewer macroaggregates (>250 μm) and associated C and N than CC and CS, but free silt and clay (<53 μm) and microaggregates (53–250 μm) were enriched in C and N in CSW. Yield and macroaggregate-occluded C and N were negatively correlated. Yield and 5–25 cm free silt and clay C were positively correlated.

Conclusions

While organic matter in aggregate-occluded fractions is beneficial for soil C storage, it was correlated with lower grain yields, highlighting a potential tradeoff between yield and long-term C sequestration.

     

African Hepatics: VIII. Diplasiolejeunea albifolia (Taylor) E. W. Jones comb.nov.

Abstract

The new combination Tetralophozia filiformis (Steph.) E. Urmi is proposed for Chandonanthus filiformis Steph. So far this species has been known only from Asia and N. America. Recent collections show it to occur also in Europe, in the Cantabrian Mts., Spain. Here it grows in sheltered places on siliceous rocks in oceanic conditions. From Tetralophozia setiformis (Ehrh.) Schljak. (=Chandonanthus setiformis) it is distinguished by its smaller size, the leaf lobes are always more than twice as long as wide and their margins are not inflexed towards the stem.     

Relationships among Cratoneuron curvicaule,C. filicinum var. filicinum,and C. filicinum var. atrovirens (Bryophyta: Amblystegiaceae)

Abstract

The relationships among western Eurasian and Macaronesian Cratoneuron filicinum (Hedw.) Spruce var. filicinum, C. filicinum var. atrovirens (Brid.) Ochyra, and C. curvicaule (Jur.) G.Roth were explored by ITS and the chloroplast markers rpl16 and tRNA-Gly. Haplotype networks, Jacknife, and Neighbour joining trees all provide high support for the recognition of C. curvicaule as distinct from C. filicinum, whereas the two varieties of the latter could not be distinguished. It is concluded that C. filicinum var. atrovirens most likely represents a phenotypic modification of C. filicinum that occurs especially in certain submerged environments or under heavily dripping water. The maximal support for the Cratoneuron clade and the small and quantitative morphological differences between its two species are arguments for not splitting this genus.     

Physcomitrium,eurystomum Sendtn. in Britain

Abstract

Key to the genera Marchesinia, Dicranolejeunea and Lopholejeunea. D. johnsoniana (Mitt.) comb.nov. from Macaronesia is figured and described in detail. The South African Marchesinia chrysophylla is transferred to Dicranolejeunea and is regarded as conspecific with D. atra (Mitt.) Vanden Berghen, syn.nov. from Central Africa.     

EFFECTS OF TEMPERATURE,NITROGEN SUPPLY,AND TISSUE NITROGEN ON AMMONIUM UPTAKE RATES OF THE CHLOROPHYTE SEAWEEDS ULVA CURVATA AND CODIUM DECORTICATUM1

Nitrogen uptake rates of Ulva curvata (Kütz.) de Toni (Ulvales) and Codium decorticatum (Woodw.) Howe (Caulerpales) grown under several N addition regimes were determined by perturbation and continuous mode techniques, and as N demand, by the product of growth rate and tissue N. Uptake rates are reported as the slope of rate vs. concentration curves in each case. N uptake rates of U. curvata were inversely correlated with tissue N and affected only slightly by temperature. There was no correlation of N uptake rate with tissue N in C. decorticatum. N uptake rates of C. decorticatum were affected by temperature but to a lesser degree than were growth rates. Neither N addition per se nor light affected N uptake capacity of either species. The proximal mechanism for seaweeds accumulation of N at low light and temperatures may be that N uptake is less limited by light and temperature than is growth. This in turn may partially compensate for the effects of reduced light and temperature on growth by increasing pigment and enzyme levels. Perturbation uptake rates were higher than continuous mode or N demand rates in Ulva but not in Codium. N uptake rates of Ulva were higher than those of Codium, but N storage capacities were lower. These two observations suggest that Ulva experiences a fundamentally more variable N supply than does Codium. This is consistent with the clarification of Ulva as an ephemeral form and of Codium as persistent. A seaweed's functional form therefore appears to influence the spectrum of resource variability available to it as well as its ability to persist in the environment.     

甲烷菌对厌氧真菌不同碳源代谢的影响

【目的】探讨碳源和甲烷菌对厌氧真菌碳代谢的影响。【方法】利用体外批次厌氧发酵法,比较厌氧真菌纯培养(Orpinomyces sp.和Neocallimastix sp.)及其与甲烷菌共培养(F1:Orpinomyces sp.+Methanobrevibacter sp.和N3:Neocallimastix sp.+Methanobrevibacter sp.)发酵不同类型碳水化合物代谢产物的差异。【结果】对厌氧真菌和甲烷菌共培养F1和N3的研究显示,F1发酵木薯粉[(26.44±0.22)mmol/L]的乳酸产量是发酵玉米芯[(1.31±0.04)mmol/L]的20.18倍,是N3发酵木薯粉[(1.59±0.03)mmol/L]的16.63倍,玉米芯[(0.79±0.08)mmol/L]的33.47倍。当F1和N3中的厌氧真菌纯培养时,各组乳酸产量均1.90 mmol/L。对F1进一步研究,结果显示发酵体系中木薯粉添加量在0.8%–2.0%之间时,乳酸产量随木薯粉添加量增加而增加。当含量在1.0%–2.4%之间时,随木薯粉添加量增加,甲烷和乙酸产量逐渐降低。比较F1发酵大米粉、木薯粉、玉米粉、小麦粉和土豆粉的发酵结果,发现乳酸产量与底物中支链淀粉的含量成正相关(R2=0.9554)。当F1发酵葡萄糖和麦芽糖时,乳酸产量5.00 mmol/L。当以麦芽糊精为底物时,乳酸产量高达(28.00±0.95)mmol/L。【结论】本文首次报道碳源和甲烷菌能够增强厌氧真菌的乳酸代谢途径并且这种增强存在种属特异性。     

The Genetics of Bryophytes

Abstract

Sanionia orthothecioides (Lindb.) Loeske (Drepanocladus orthothecioides (Lindb.) Roth) is reported from three Scottish islands, Hirta (St Kilda), Mainland of Shetland and Fair Isle, new to the British Isles. It is described and illustrated and the differences with the closely related S. uncinata (Hedw.) Loeske discussed.     

Barbula sardoa (Schimp.) J.-P.Frahm,a new name for Barbula convoluta Hedw. var. commutata (Jur.) Husn.

Abstract

Barbula convoluta Hedw. var. commutata (Jur.) Husn. differs from var. convoluta not only by characters such as larger size, darker colour and undulate leaf margins, as mentioned in the literature, but, in addition, by a different transverse section of the stem, different basal laminal cells, different papillae on the leaf surface, a different spore ornamentation and different isozyme systems. It should therefore be regarded as a separate species. In this case, the legitimate name would be Barbula sardoa (Schimp.) J.-P. Frahm, since Barbula convoluta var. sardoa Schimp. is revealed to be an earlier synonym of var. commutata.     

Lejeunea laii nom. nov. for Lejeunea ramulosa (Herzog) R.M.Schust. (Jungermanniopsida: Lejeuneaceae) from Taiwan

Abstract

B. trachypodium (Brid.) B., S. &; G. is added to the British list from a new locality in Inverness-shire (v.-c. 97). An old record from Perthshire (v.-c. 88), discredited by H. N. Dixon, is accepted.     

Patterns of soil and plant nitrogen isotope composition and their relationships with climate factors in Xilingol League,Inner Mongolia,China

Background: Plant and soil nitrogen stable isotope (δ¹⁵N) can integrate several fundamental biogeochemical processes in ecosystem nitrogen dynamics, and reflect characteristics of ecosystem nitrogen cycling.

Aims: We investigated how climate change influenced plant-soil nitrogen cycling by relating soil δ¹⁵N, plant δ¹⁵N and Δδ¹⁵N (difference between soil and plant δ¹⁵N) with climatic factors.

Methods: Field investigation was conducted in temperate grasslands in Inner Mongolia during August 2015. Plant δ¹⁵N, soil δ¹⁵N and Δδ¹⁵N were determined, and their relationships with climatic factors were examined by simple regression analyses and general linear models.

Results: Soil δ¹⁵N was significantly higher than plant δ¹⁵N, and there was a positive linear correlation between them. Soil and plant δ¹⁵N were negatively related with mean annual precipitation (MAP) and positively with mean annual temperature (MAT); conversely, Δδ¹⁵N was positively related with MAP and negatively with MAT.

Conclusion: Soil δ¹⁵N was dominantly controlled by MAT, while it was MAP for plant δ¹⁵N. Climate factors influenced plant δ¹⁵N not only through their effects on soil nitrogen dynamics but also strategies of plant nitrogen acquisition. Thus, compared with plant δ¹⁵N, soil δ¹⁵N can more accurately reflect soil nitrogen dynamics, while plant δ¹⁵N may integrate soil nitrogen dynamics and plant nitrogen acquisition.     

Grimmia homodictyon Dixon

Abstract

We examined photosynthetic responses of two dominant pleurocarpous mosses, Actinothuidium hookeri (Mitt.) Broth. and Hylocomium splendens (Hedw.) Schimp. to low-level nitrogen (N) addition. The study was conducted in an old-growth fir forest on the eastern Tibetan Plateau. The added N, 1 g N/m², was mainly absorbed by the new-growth. The concentrations of chlorophyll a and b both increased 8 days after N addition. The quantum yield of Photosystem II (Φ_PSII) also increased. However, no significant changes were found in terms of gas exchange parameters. The mass-based CO₂ assimilation rate, chlorophyll a content, and chlorophyll a/b ratio (which is related to antenna size of the photosystem), of H. splendens were all higher than those of A. hookeri. Shoot mass per area (SMA) of H. splendens was lower than that of A. hookeri. We conclude that the photosynthetic rate was less sensitive to low-level N addition than chlorophyll contents and chlorophyll fluorescence parameters, suggesting other limiting factors in the photosynthetic process. Additionally, the faster growing H. splendens has a higher photosynthetic capacity than A. hookeri, allocating fewer resources to structural tissue.     

Notes on mosses from Ceylon and India, 7. Some species of Trichostomum

Abstract

Trichostomum bombayense C.M. is typified and T. cylindrotheca Mitt. reduced to synonymy under it. The records of Trichostomum species from Ceylon are critically examined and T. tenuirostre (Hook. & Tayl.) Lindb. removed from the Ceylon moss flora. Records of T. orthodontum (C.M.) Broth. and T. cuspidatum (D. & M.) D. & M. hitherto published are based on misidentifications, but new records are given of both. Differences between T. cuspidatum and T. stenophyllum (Mitt.) Broth., which latter binomial is not a homonym as Index Muscorum states, are dealt with and illustrated by S.E.M. photographs. T. stenophyllum is a good species which has been relegated to extraordinary synonymy in the past.     

Aphannotropis Herz., eine neue Gattung der Lejeuneaceae aus Borneo

Abstract

In the course of investigations in the Hyrcanian region of northern Iran, especially of epiphyte vegetation in the Elburz Mountains south of the city of Nowshahr (36°39′N, 51°30′E), 18 moss species that have not been reported from the country earlier were found. Several of the new finds represent major range extensions, or fill gaps in the known distributions of the species, for example, Lescuraea saviana (DeNot.) E.Lawton, Rhynchostegium rotundifolium (Brid.) Schimp., and Schwetschkeopsis fabronia (Schwägr.) Broth. In addition, the presence of both Plagiothecium nemorale (Mitt.) A.Jaeger and P. succulentum (Wilson) Lindb. is confirmed for Iran.     

Long-term response of Sitka spruce (Picea sitchensis (Bong.) Carr.) to CO2 enrichment and nitrogen supply. I. Growth,biomass allocation and physiology

ABSTRACT

After a 3-year exposure to elevated CO₂, young trees of Sitka spruce (Picea sitchensis (Bong.) Carr.) were planted in native, nutrient-deficient forest soil and grown for two more years with three CO₂ treatments in open-top chambers, and with two nutrient treatments (with and without supplied N). Elevated CO₂ resulted in larger fresh mass, dry mass, leaf area and leaf thickness in two-year old needles, but had no effect on one-year old and current needles. Tree height, basal diameter and biomass production also increased, regardless of N supply. In trees without added N, elevated CO₂ resulted in higher root-to-shoot and absorbing roots-to-stump ratios. Regardless of N supply, trees grown in elevated CO₂ had lower photosynthetic rates on a leaf area basis. Photosynthesis reduction was accompanied by a decline in Rubisco activity and leaf N concentration. Under elevated CO₂, added N elevated photosynthesis and Rubisco activity, suggesting a dependence on N availability of the photosynthetic response to elevated CO₂. Stomatal conductance of trees grown with added N decreased in response to elevated CO₂. This may account for the larger reduction in intercellular CO₂ concentration, and hence photosynthesis, in the trees supplied with N than in those without N supply.     

Nothotalisia, a new genus of Picramniaceae from tropical America

A new genus of Picramniaceae from tropical America, Nothotalisia, is described. Of the three species in the genus, N. piranii and N. cancellata, are new to science. The third, N. peruviana, was originally described as Talisia peruviana in the Sapindaceae. The genus and all three species are described, illustrated, and distinguished by means of a key.