Physiological and biochemical aspects of tolerance of three grass species to varying Na+/Ca2+ ratios

The effects of decreasing Ca²⁺ concentrations (Na/Ca ratios were 24, 49, 99 and 199) of the saline growth medium (NaCl concentration 200 mM) on three grass speciesCenchrus pennisetiformis Hochst. & Steud,Leptochloa fusca L. Kunth. andPcmicum turgidum Forssk. were assessed after 7 weeks growth in sand culture.L. fusca produced the highest dry biomass of all the species at varying Na/Ca ratios. Number of tillers per plant and number of green leaves per tiller were reduced significantly only inC. pennisetiformis. Leaf water potential ofC. pennisetiformis decreased at all external Na/Ca ratios, whereas inL. fusca it decreased only at an Na/Ca ratio of 99. Leaf osmotic potential ofL. fusca consistently decreased at all Na/Ca ratios, whereas that of the other two species remained unchanged. The shoot and root total sugars of all species remained unaffected at all decreasing Ca²⁺ concentrations. InP. turgidum chlorophyllb and total chlorophyll decreased consistently at all Na/Ca ratios, but inL. fusca they decreased only at the highest Na/Ca ratios. The leaf soluble proteins of all the species remained unaffected at all Na/Ca ratios. The leaf free amino acids decreased significantly inL. fusca with the increase in Na/Ca ratios. The leaf proline content was only decreased inL. fusca at the highest Na/Ca ratio. The significant correlations between the growth of the three grass species and other variables determined in this study were not found.     

Population studies in Goodyera (Orchidaceae) with emphasis on the hybrid origin of G. Tesselata

Morphological, cytological, and paper Chromatographic studies of populations from northern Michigan and examination of herbarium specimens from throughout North America were used to clarify the relationships ofGoodyera oblongifolia, G. repens var.ophioides, andG. tesselata. A canonical analysis of morphological data from mixed populations of these three species depictsG. tesselata as intermediate betweenG. oblongifolia andG. repens var.ophioides. The latter two species are diploid (2n = 30) andG. tesselata is tetraploid (2n = 60). Triploids (2n = ca. 45) were found in two mixed-species populations in northern Michigan.Goodyera tesselata produces three phenolic compounds present inG. oblongifolia and five different compounds present inG. repens var.ophioides. The range ofG. tesselata is confined to glaciated territory (except for two stations) in northeastern North America where the postglacially produced ranges ofG. oblongifolia andG. repens var.ophioides overlap. However,G. tesselata is quite abundant in areas outside the region of sympatry of the other two species. Based on this evidence, it is postulated thatG. tesselata is an allotetraploid species which resulted from hybridization betweenG. oblongifolia andG. repens var.ophioides during early post-Pleistocene. The slightly earlier blooming season ofG. tesselata may have been selected for to provide a measure of reproductive isolation between the tetraploid and its parents and to adapt the new species to the rather short growing season of northeastern North America.     

The potential host ranges in Australia of some imported aphid parasites [Hym: Ichneumonoidea: Aphidiidae]

Host selection trials on restricted populations of the aphidiid parasites,Lysiphlebus fabarum (Marshall) andL. testaceipes (Cresson), imported into Australia as biological control agents ofAphis craccivora Koch, the cowpea aphid, have shown that these imported parasites are not widely polyphagous, and thus support a view that the 2 species, as presently recognized, each represent a complex of host-restricted biotypes or of sibling species. Whereas both of the importedLysiphlebus readily oviposited in species ofAphis andToxoptera, and developed successfully to adulthood inA. craccivora, A. gossypii Glover andT. aurantii (Boyer de Fonscolombe), they failed to complete development inA. citricola van der Goot, one of the most common aphid species in Australia, and only a small number completed development inT. citricidus (Kirkaldy). Both of these hosts, then, act as “egg traps” for theLysiphlebus. A. nerii Boyer de Fonscolombe was a suitable host forL. testaceipes but not forL. fabarum. NeitherL. fabarum notL. testaceipes oviposited inCavariella aegopodii (Scopoli),Brevicoryne brassicae (L.),Brachycaudus helichrysi (Kaltenbach),B. persicae (Passerini),Hyperomyzus lactucae (L.),Acyrthosiphon kondoi Shinji,A. pisum (Harris),Macrosiphum euphorbiae (Thomas) orM. rosae (L.); andL. fabarum did not oviposit inRhopalosiphum padi (L.) orMyzus persicae (Sulzer). The prognosis for the effective establishment in Australia of these 2 parasites is therefore not good In contrast, another purportedly polyphagous aphidiid,Praon volucre (Haliday), imported into Australia to help effect control ofH. lactucae, the sowthistle aphid, successfully and effectively parasitizedMacrosiphum euphorbiae, M. rosae, Acyrthosiphon pisum, A. kondoi, Aulacorthum solani (Kaltenbach),Myzus persicae andAphis craccivora, in addition toH. lactucae.     

Osmotic adjustment in leaves ofLycopersicon esculentum andL. pennellii in response to saline water irrigation

Two tomato species (Lycopersicon esculentum andL. pennellii) were grown under unheated plastic greenhouse and irrigated with 0 or 140 mM NaCl. Salinity induces a more important reduction in predawn leaf water potential (ψ_pd) inL. esculentum than inL. pennellii. In both species the osmotic adjustment was achieved by active solute accumulation. The leaf water potential at turgor loss point (ψ_tlp) seemed to be controlled by leaf osmotic potential (ψ_os). The results revealed the existence of limits to the accumulation of osmotic solutes in leaf tissues and the existence of an ontogenetic effect on the solute accumulation. In both species, but essentially inL. pennellii the inorganic solutes contribution especially Na⁺ and Cl^? accumulation to ψ_os was higher than the organic solutes. Therefore, wild species save energy more markedly.     

Nitrogen in litterfall and precipitation and its release during litter decomposition in the Chilean piedmont matorral

Parts of the nitrogen cycle involving two dominants (Lithraea caustica andQuillaja saponaria) in the Chilean piedmont matorral have been studied over a 15-month period. Analyses showed that 8.2 kg N ha^?1 yr^?1 entered the system in rainfall and dry deposition, though impaction of N-containing compounds on vegetation (not measured) may elevate this value.L. caustica, by virtue of its greater percent cover, contributed more leaf litter than didQ. saponaria to the system (1089,vs 737 kg dry matter ha^?1 yr^?1, respectively), although on an individual basisQ. saponaria produced more litter (640,vs 350 g dry leaf litter m^?2 yr^?1 rL. caustica). This plus the greater nitrogen release ofL. caustica leaf litter during decomposition (2.61,vs 0.60 g N kg dry litter^?1 yr^?1 forQ. saponaria) andQ. saponaria's higher N-content of dropped leaves (0.54,vs 0.37% N forL. caustica) may indicate a more external cycling of nitrogen inQ. saponaria relative to that inL. caustica. These two species may therefore represent two different strategies of individual nitrogen cycling, external and internal.     

Indigofera oblongifolia leaf extract regulates spleen macrophage response during Plasmodium chabaudi infection

Malaria is a major health problem that still affects numerous countries. The current study aimed to identify the role of Indigofera oblongifolia leaf extract in regulating mouse spleen macrophages during the progression of Plasmodium chabaudi infection. Three doses of the leaf extract (100, 200, and 300 mg/kg) were administered to mice inoculated with P. chabaudi infected erythrocytes. The weight of the infected mice improved after the treatment with I. oblongifolia. The infection causes disorganization of macrophage distribution in the spleen. After the mice had been treated with the leaf extract, the macrophages appeared to be reorganized in the white and red pulp areas. In addition, the I. oblongifolia leaf extract (IOLE) significantly increased the total antioxidant capacity of the mice spleens infected with P. chabaudi. The phagocytic activity of spleen macrophages was increased in the infected group as indicated by the significant decrease in the number of fluorescent particles in the spleen sections. This number increased in the mice spleens after treatment with IOLE. Based on these results, it is suggested that IOLE regulate macrophage response of the spleen during the blood stage of malaria in mice.     

Neotypification of Amellus villosus,the identity of a bradbury collection,and typification of some other goldenasters (Compositae: Astereae)

Nomenclatural problems involving closely related North American goldenasters are resolved. No original type material (a collection by John Bradbury) is known forAmellus villosus Pursh, which is the basionym for the taxon referred to asChrysopsis villosa and more recently asHeterotheca villosa. The species is the first-described taxon inHeterotheca sect.Phyllotheca. A collection by Bradbury (LIV) was found to belong inH. camporum and does not match Pursh's protologue. A neotype (PH) was selected from collections by Thomas Nuttall. A problem in the typification of the second oldest taxon in sect.Phyllotheca was encountered. The specimen filed at K as the type ofDiplopappus hispidus Hook. was not the specimen cited in the protologue. A lectotype has been designated from collections by Richardson at BM. Other taxa placed in synonymy are also typified.     

Life history told by a whale-louse: a possible interaction of a southern right whale <Emphasis Type="Italic">Eubalaena australis</Emphasis> calf with humpback whales <Emphasis Type="Italic">Megaptera novaeangliae</Emphasis>

Southern right whales (Eubalaena australis) are known to host three species of whale-lice, Cyamus gracilis, Cyamus ovalis and Cyamus erraticus. Such cyamids usually are generalists in toothed whales (Cetacea: Odontoceti) and host-specific in baleen whales (Cetacea: Mysticeti), and because they have no free-swimming stage, transmission only occurs by contact between whales. One southern right whale stranded at the southeastern coast of Brazil was found parasitized by a different species of cyamid. Over 300 specimens were collected and the only species identified based on morphological and molecular data was Cyamus boopis, a typical ectoparasite of humpback whales (Megaptera novaeangliae). This finding is the first record of C. boopis on the southern right whale. Both E. australis and M. novaeangliae are found in Brazilian waters and the presence of humpback’s whale-louse together with the lack of the three specific parasites of right whales suggest an interspecific interaction between these whales based on the parasite’s biology.     

Molecular characterization of ‘Clover proliferation’ phytoplasma subgroup-D (16SrVI-D) associated with vegetables crops in India

Nine vegetable plants species exhibiting phytoplasma suspected symptoms of white/purple leaf, little leaf, flat stem, witches’ broom, phyllody and leaf yellowing were observed in experimental fields at Indian Agricultural Research Institute, New Delhi from December 2015 to July 2016. Total DNA extracted from the three healthy and three symptomatic leaves of all the nine vegetables were subjected to PCR assays using phytoplasma specific primers P1/P7 followed by R16F2n/R16R2 and 3Far/3Rev to amplify the 16S rDNA fragments. No amplifications of DNA were observed in first round PCR assays with primer pair P1/P7 from any of the symptomatic samples. However, phytoplasma DNA specific fragments of ~ 1.3 kb were amplified from Apium graveolens L. (two isolates), Brassica oleracea vr. capitata L. (one isolate) and Solanum melongena L. (one isolate) by using 3Far/3Rev primer pair and 1.2 kb fragment was amplified from Lactuca sativa L. (one isolate) by using R16F2n/R16R2 primer pair. No DNA amplification was seen in other symptomatic vegetable samples of tomato, carrot, cucurbit, bitter gourd and Amaranthus species utilizing either P1/P7 primer pair followed by 3Far/3Rev or R16F2n/R16R2 primer pairs. Out of three leafhopper species collected from the symptomatic vegetable fields, only Hishimonus phycitis was found positive for association of phytoplasma. No DNA amplifications were observed in healthy plant samples and insects collected from non-symptomatic fields. Comparative sequence comparison analyses of 16S rDNA of positive found vegetable phytoplasma strains revealed 100% sequence identities among each other and with phytoplasma strains of ‘clover proliferation’ (16SrVI) group. Phytoplasma sequences, virtual RFLPs and phylogenetic analyses of 16S rDNA sequence comparison confirmed the identification of 16SrVI subgroup D strain of phytoplasmas in four vegetables and one leafhopper (HP) species. Further virtual RFLP analysis of 16S rDNA sequence of the vegetables phytoplasma strains confirmed their taxonomic classification with strains of ‘clover proliferation’ subgroup D. Since, H. phycitis feeding on symptomatic vegetable species in the study was also tested positive for the 16SrVI phytoplasma subgroup-D as of vegetables; it may act as potent natural reservoir of 16SrVI-D subgroup of phytoplasmas infecting vegetable and other important agricultural crops.     

Notulae de Chrysobalanaceis Malesianis Praecursoriae

In preparation for the treatment of Chrysobalanaceae forFlora Malesiana, New and critical taxa are discussed and described. Two new species were found,Atuna cordata andParastemon grandifructus.Hunga fusicarpa is transferred to the genusLicania asL. fusicarpa. Species complexes aroundParinari costata andP. papuana are discussed; in both cases previously recognized species are reduced to subspecific rank within rather polymorphic species.     

Activation of non-photochemical quenching in thylakoids and leaves

The mechanism of rapidly-relaxing non-photochemical quenching in two plant species,Chenopodium album L. andDigitalis purpurea L., that differ considerably in their capacity for such quenching has been investigated (Johnson G.N. et al. 1993, Plant Cell Environ.16, 673–679). Illumination of leaves of both species in the presence of 2% O₂ balance N₂ led to the formation of zeaxanthin. When thylakoids were isolated from leaves of each species that had been so treated it was found that inD. purpurea non-photochemical quenching was “activated” relative to the control; a higher level of quenching was found for a given trans-thylakoid pH gradient. No such activation of non-photochemical quenching was observed inC. album. Similar conclusions were drawn when comparing quenching in intact leaves. It is concluded that light activation of quenching is a process that cannot readily be induced inC. album. Measurement of the sensitivity of non-photochemical quenching in leaves ofC. album andD. purpurea to dithiothreitol (DTT; a reagent that inhibits formation of zeaxanthin) showed differences between the two species. In both cases, feeding leaves with DTT inhibited the light-induced formation of zeaxanthin. InC. album this was accompanied by complete inhibition of reversible non-photochemical quenching, whereas inD. purpurea this inhibition was only partial. Data are discussed in relation to studies on the mechanism of quenching and the role of zeaxanthin in this process.     

Conocephalum salebrosum (Marchantiopsida, Conocephalaceae) – a new Holarctic liverwort species

Detailed analysis of 270 specimens of Conocephalum conicum (L.) Dumort., mainly from the POZW Herbarium revealed some diagnostic differences between two cryptic species originally detected on the basis of isozyme studies. Several diagnostic characters were found in the structure of the archegoniophore, sporophyte and sterile thallus. The most reliable diagnostic features are size and structure of stomatal apparatus of the archegoniophore ‘heads’, type of junction of the air chamber walls with epidermal cells, and the thallus surface details. On the basis of morphological and anatomical diagnostic characters, two formerly cryptic species are recognized following the rules of formal taxonomy. The lectotype of C. conicum preserved in FI was found to possess characteristics of cryptic species C. conicum- species L. Accordingly, the species previously named as C. conicum–species L must bear the name Conocephalum conicum (L.) Dumort. No published name was related to C. conicum – species S, which is therefore described as a new species: Conocephalum salebrosum Szweykowski, Buczkowska &; Odrzykoski. Both species are fully described and their diagnostic characters are illustrated. Distribution maps for both species are given.     

A survey of C-band patterns in chromosomes ofLilium (Liliaceae)

C-band patterns are described for 20Lilium spp. distributed across six sections. All species have a similar basic karyotype (n = 12) but C-bands differ markedly between them. The patterns are characterized by a dispersed scattering of thin intercalary bands as well as centric and NOR bands. Only one species,L. canadense, shows a clear equilocal pattern with intercalary C-bands occurring proximally in all of the longer chromosome arms. Comparing species, similar patterns are revealed forL. regale andL. sulphureum, forL. formosanum andL. longiflorum (all in sect.Leucolirion) and to a lesser extent forL. hansonii, L. martagon, andL. tsingtauense (sect.Martagon). The pattern forL. henryi (previously classed in sect.Sinomartagon) matches those ofL. regale andL. sulphureum quite well and its transfer to sect.Leucolirion is proposed. This is consistent with results from interspecies hybrids betweenL. henryi andL. regale (and related species) which are reportedly fertile. No other clear similarities in C-band patterns were seen across species. It seems that C-band patterns change rapidly inLilium and hence their usefulness in classification will be restricted to identifying closely related species.Dedicated to Prof.D. G. Catcheside on the 80th anniversary of his birth.     

Culture-independent analysis of an endophytic core microbiome in two species of wheat: Triticum aestivum L. (cv. ‘Hondia’) and the first report of microbiota in Triticum spelta L. (cv. ‘Rokosz’)

The main goal of the study was to determine the structure of endophytic bacteria inhabiting different parts (endosperm, germ, roots, coleoptiles, and leaves) of two wheat species, Triticum aestivum L. (cv. ‘Hondia’) and Triticum spelta L. (cv. ‘Rokosz’), in order to provide new knowledge about the stability and/or changeability of the core microbiome in different plant organs. The endophytic core microbiome is associated with plants throughout their whole life cycle; however, plant organs can determine the actual endophytic community. Therefore, next generation sequencing with MiSeq Illumina technology was applied to identify the endophytic microbiome of T. aestivum and T. spelta. Bioinformatic analyses were performed with the use of the DADA2(1.8) package and R software (3.5.1).It was demonstrated that wheat, which is an important crop plant, was associated with beneficial endophytic bacteria inside the endosperms, germs, roots, leaves, and coleoptiles. Importantly, for the first time, biodiversity was recognized in the coleoptiles of the investigated wheat species. Flavobacterium, Pseudomonas and Janthinobacterium were shown to be common genera for both tested wheat cultivars. Among them, Pseudomonas was found to be the only endophytic genus accompanying both wheat species from the endosperm stage to the development of the leaf. Paenibacillus was recognized as a core genus for the ‘Hondia’ cv., whereas Pedobacter and Duganella constituted the core microbiome in the ‘Rokosz’ cv. In addition, the first insight into the unique and yet unrecognized endophytic microbiome of T. spelta is presented.     

Specific leaf weight and photosynthetic rate in sugar beet leaves of different age

No proportional changes in the photosynthetic rate,P, (measured as the dry weight increments in leaf discs) as related to the specific leaf weight,SLW (i.e. leaf dry weight per unit leaf area) were found because of different variation inP andSLW, respectively, with the age and insertion level of individual sugar beet leaves as well as with the age of the whole plant.     

Speciation and paraphyly in western mediterranean hares (Lepus castroviejoi,L. europaeus,L. granatensis,andL. capensis) revealed by mitochondrial DNA phylogeny

Mitochondrial DNA (mtDNA) variation among specimens of the northwestern African hare (Lepus capensis schlumbergeri) and three European hares sampled in Spain (L. castroviejoi andL. granatensis, which are endemic to the Iberian Peninsula, andL. europaeus) was analyzed using seven restriction endonucleases. Fourteen haplotypes were found among the 34 animals examined. Restriction site maps were constructed and the phylogeny of the haplotypes was inferred. mtDNA ofL. capensis was the most divergent, which is consistent with its allopatric African distribution and with an African origin of European hares. We estimated that mtDNA in hares diverges at a rate of 1.5–1.8% per MY assuming that the European and African populations separated 5–6 MYBP. Maximum intraspecies nucleotide divergences were 1.3% inL. capensis, 2.7% inL. castroviejoi, and 2.3% inL. granatensis but 13.0% inL. europaeus. The latter species contained two main mtDNA lineages, one on the branch leading toL. castroviejoi and the other on that leading toL. granatensis. The separation of these two lineages from theL. castroviejoi orL. granatensis lineages appears to be much older than the first paleontological record ofL. europaeus in the Iberian peninsula. This suggests that the apparent polyphyly ofL. europaeus is due not to secondary introgression, but to the retention of ancestral polymorphism inL. europaeus. The results suggest thatL. europaeus either has evolved as a very large population for a long time or has been fractionated. Such a pattern of persistence of very divergent lineages has also been reported in other species of highly mobile terrestrial mammals. As far as mtDNA is concerned,L. europaeus appears to be the common phylogenetic trunk which has diversified during dispersion over the European continent and from whichL. castroviejoi andL. granatensis speciated separately in southwest Europe.     

Impact of flower and seed predators on seed-set in two Banksia shrubs

A non-systemic Insecticide was used to exclude flower and seed predators from Banksia ericifolia and B. oblongifolia Inflorescenses. In B. ericifolia this treatment doubled the number of inflorescences that set seeds, and increased by 40% the number of seeds produced per Inflorescence. Insecticide treatment did not alter either of these components of seed-set in B. oblongifolia partly because the experiment began too late to exclude flower predators In this species. The results obtained for B. ericifolia support the hypothesis that flower and seed predators explain, in part, the low incidence of seed-bearing cones and the low seed:flower ratios reported for many Banksia species. Each Banksia species supports two guilds of Inflorescence predators. Two Lepidopteran species feed on young flowers; one of these causes tunnel damage to the rachis. Each Banksia species also supports five Lepidopteran and two Curcullonid seed-predators. About 40% of these herbivorous Insects are common to both shrubs.     

A systematic study of the genus hulsea (Asteraceae)

A systematic treatment based on genetic, biochemical, and morphological studies is presented for the 11 recognized taxa ofHulsea. A uniform diploid complement of 38 chromosomes was found in the 37 populations examined, including all species and representing first reports forH. brevifolia, H. californica, andH. mexicana. Thirteen flavonoid compounds, based on the aglycones quercetin, apigenin, cyanidin, and the 4′-O-methyl ether of luteolin, were detected inHulsea. Patterns of the flavonoid compounds are discussed with respect to the systematic treatment. The results of 595 synthetic crosses indicate thatHulsea species are self-incompatible, relatively cross-compatible, and that their F₁ hybrids are relatively fertile. Heterozygosity for one or two translocations is reported for 11 interspecific and intersubspecific hybrid combinations.     

Field evaluation of starter N and delayed inoculation ofLespedeza cuneata grown in minesoil

A field study was conducted on freshly reclaimed surface-mined area to determine response of sericea lespedeza (Lespedeza cuneata [Dumont] G. Don.) to delayed rhizobial inoculation. Soybeans (Glycine max L.) were used as a control legume. Plots were inoculated with spray applications of rhizobial suspensions at seeding, cotyledon stage or second trifoliate leaf stage, or not inoculated. Starter N at 0, 10 or 20 kg ha^?1 was applied preplant in a factorial arrangement with inoculation timings.G. max. was grown for 92 days andL. cuneata for 121 days. Starter N increased plant growth and total shoot N in both species. However, % shoot N was found to increase only inL. cuneata. Delaying inoculation had no significant effect upon total shoot N or % shoot N accumulation inL. cuneata. Inoculation ofG. max at planting produced greater plant growth and N accumulation than delayed inoculation treatments. Application of inoculum as a surface spray appeared to be an effective method for delayed inoculation as evidenced by nodule formation. Lack of increased plant growth, regardless of time of inoculation, suggests that delayed inoculation does not improve establishment and growth ofL. cuneata in minesoil.