Auxin induced morphogenetic responses in long-term in vitro subcultured Mammillaria san-angelensis Sánchez-Mejorada (Cactaceae)

Observations were made as to the influence of auxins, as the sole exogenous growth regulator, on the morphogenesis of long-term in vitro subcultured plantlets of the severely endangered cacti Mammillaria san-angelensis. Sections of long-term subcultured shoots were exposed to different auxins at various concentrations, and plant regeneration was recorded as a direct effect of auxin concentration. It was found that morphogenetic potentiality was retained in long-term subcultures, and that the best regeneration was seen in the presence of IAA (34.25 μM). Histological analysis revealed two processes leading to regeneration: de novo production of shoots and axillary meristem activation. Of the two, de novo shoot production was found to occur both in controls and in explants growing in the presence of IAA, while axillary meristem activation was observed only in the presence of IAA.     

Can Mineral Analysis be Used as a Tool to Predict ‘Braeburn’ Browning Disorders (BBD) in Apple in Commercial Controlled Atmosphere (CA) Storage in Central Europe?

‘Braeburn’ apples stored in controlled atmosphere (CA) frequently present internal flesh browning physiological disorder which is commonly referred as ‘Braeburn’ Browning Disorder (BBD). Apples from different orchards, years or site conditions can vary considerably in their sensitivity. The aim of this research was to evaluate the relationship between the mineral status of ‘Braeburn’ apples before-harvest (18 days) and at early and normal harvest, to correlate the data with the BBD incidence found in apples post storage and to investigate possible reasons for differences in disorder sensitivity. Fruits from seven orchards in the Lake Constance area (South-Western Germany) were harvested at two picking dates and the mineral content was measured before-harvest, at-harvest and during storage. Fruit were stored at 1.5?°C under CA conditions (1 kPa O₂ and 0.5 kPa CO₂) using either a 10 days or a 24 days delayed establishment of CA conditions. Fruit were evaluated after 6 months of storage plus 10 days of shelf life at 18?°C for mineral status and the browning disorder incidence. Results indicate no significant changes of the mineral concentrations in the fruit during CA-storage. Significant correlations between the post storage BBD incidence with K, and in some cases also for the K/Ca ratio and for P at-harvest were found.     

Nitric oxide in combination with indole-3-butyric acid improves root growth in ‘Ferdor Julior’ hardwood cuttings (Prunus insistitia (L.) × Prunus domestica (L.))

The production of plants for high density fruit orchards requires a highly efficient clonal propagation method. ‘Ferdor Julior’ rootstock is well adapted to different soil conditions, but its natural rooting potential is very limited. Propagation treatments, such as bottom heat and indole-3-butyric acid (IBA) applications have previously been used to improve rooting. The aim of this work is to evaluate the effects of either IBA, or sodium nitroprusside (SNP; a nitric oxide (NO) donor), or a combination of both on the rooting of hardwood cuttings of ‘Ferdor Julior’. As metabolism markers, ascorbic acid (AA) and glutathione (GSH) were measured in adventitious roots. ‘Ferdor Julior’ hardwood cuttings were treated as follows: untreated, 0.3 mM IBA, 1 mM SNP, 1 mM SNP previously exposed to light (as a negative control), and 1 mM SNP + 0.3 mM IBA. After 4 months, the combined use of SNP and IBA had increased root growth and lateral rooting, but resulted in less shoot growth, whilst AA and GSH concentrations were also reduced. IBA and SNP individual treatments showed intermediate results, compared to untreated cuttings. According to the results obtained, there may be an additive effect of auxin and NO signaling pathways. In conclusion, this new and promising technique for ‘Ferdor Julior’ propagation could improve lateral root development and promote early lateral root growth.     

Legacy effects of past land use on current biodiversity in a low-intensity farming landscape in Transylvania (Romania)

Context

Ecological impacts of past land use can persist for centuries. While present-day land use is relatively easy to quantify, characterizing historical land uses and their legacies on biodiversity remains challenging. Southern Transylvania in Romania is a biodiversity-rich area which has undergone major political and socio-economic changes, from the Austro-Hungarian Empire to two World Wars, communist dictatorship, capitalist democracy, and EU accession—all leading to widespread land-use changes.

Objectives

We investigated whether present-day community composition of birds, plants, and butterflies was associated with historical land use.

Methods

We surveyed birds, plants, and butterflies at 150 sites and classified those sites as forest, arable land, or managed grassland for six epochs using historical maps from the 1870s, 1930s, and 1970s, satellite imagery from 1985 to 2000, and field visits in 2012. Sites were labelled permanent if they had the same land use at all epochs and non-permanent otherwise. We used clustering and PERMANOVA based on community similarity to test for associations between community composition and land-use history.

Results

We found significant differences (p = 0.030) in bird communities between permanent and non-permanent forest sites, and permanent and non-permanent grassland sites (p = 0.051). No significant associations were found among plants or butterflies and land-use history.

Conclusions

Bird communities were associated with historical land use, though plants and butterflies were not. Historical land-use change in our study area was likely not sufficiently intense to cross relevant ecological thresholds that would lead to legacy effects in present-day plant and butterfly communities.

     

Analysis of differentially expressed proteins in the pollen of Malus spectabilis (crabapples) and Malus domestica (‘Gala’ apples) and their role in pollination

Our objective was to study the differentially expressed proteins (DEP) in various Malus spectabilis (crabapple) varieties (M. ‘Snowdrift’, M. ‘Hongling’ and M. ‘Hongjin’) in relation to Malus domestica (‘Gala’) and their role in pollination. Our method used a two-dimensional electrophoresis (2-DE) to analyse the differential proteins in the pollen of several crabapples. The 2-DE apples combined with the tandem mass spectrometry (MS-MS) and protein database retrieval helped us to identify the nature and function of DEPs in ‘Gala’ apples and crabapples. We identified 1195 proteins through 2-DE. Among these, six DEPs, namely chloroplast ferritin, Actin, Beta-fructofuranosidase, vacuolarH+-ATPase catalytic subunit, Full = Phosphoglucomutase, and Cytochrome b were identified by MS-MS. This study identified six DEPs among the pollen from the ‘Snowdrift’ crabapple, ‘Hongling’ crabapple, ‘Hongjin’ crabapple, and ‘Gala’ apples. The DEPs included metabolism related proteins, stress/regulatory proteins, and proteins involved in signal transduction.     

Phenology of strawberry guava (Psidium cattleianum) in ReÂunion Island

Summary

The phenology of wild stands of strawberry guava (Psidium cattleianum Sabine) was studied at 100, 480 and 720.m over 2 years in ReÂunion Island. The shoots bore flower buds at the basal nodes, and vegetative buds at the apical nodes. Trees produced vegetative growth from September to December, flowers from November to January and fruit from February to June. Shoot growth was earlier at 100 and 720.m the first year, but were synchronized in the second year. Flowering and fruiting were also earlier at 100.m. The intervals between shoot emergence and flowering, and flowering and fruit maturity were strongly related to temperature, with base temperatures of 5.58C and 2.68C, and heat units requirements of 675 and 2,5528C.d, respectively. The number of shoots, flowers and fruit per branch varied across sites and years, unrelated to temperature. However, production was significantly higher at 720.m. Production was much lower after a hurricane. Flowering (y) was related to shoot production per branch (x) (log(y)=111.33.log(x); r².=.0.78), whereas the fruit set rate was highly variable between trees (26±100%). The number of fruits per branch (1±6) was possibly related to poor shoot growth or fruit set, but unrelated to the timing of the phenological events. It is expected that commercial orchards would be more productive than feral stands.     

Drivers and trends in landscape patterns of stand-replacing fire in forests of the US Northern Rocky Mountains (1984–2010)

Context

Resilience in fire-prone forests is strongly affected by landscape burn-severity patterns, in part by governing propagule availability around stand-replacing patches in which all or most vegetation is killed. However, little is known about drivers of landscape patterns of stand-replacing fire, or whether such patterns are changing during an era of increased wildfire activity.

Objectives

(a) Identify key direct/indirect drivers of landscape patterns of stand-replacing fire (e.g., size, shape of patches), (b) test for temporal trends in these patterns, and (c) anticipate thresholds beyond which landscape patterns of burn severity may change fundamentally.

Methods

We applied structural equation modeling to satellite burn-severity maps of fires in the US Northern Rocky Mountains (1984–2010) to test for direct and indirect (via influence on fire size and proportion stand-replacing) effects of climate/weather, vegetation, and topography on landscape patterns of stand-replacing fire. We also tested for temporal trends in landscape patterns.

Results

Landscape patterns of stand-replacing fire were strongly controlled by fire size and proportion stand-replacing, which were, in turn, controlled by climate/weather and vegetation/topography, respectively. From 1984 to 2010, the proportion of stand-replacing fire within burn perimeters increased from 0.22 to 0.27. Trends for other landscape metrics were not significant, but may respond to further increases proportion stand-replacing fire.

Conclusions

Fires from 1984 to 2010 exhibited tremendous heterogeneity in landscape patterns of stand-replacing fire, likely promoting resilience in burned areas. If trends continue on the current trajectory, however, fires may produce larger and simpler shaped patches of stand-replacing fire with more burned area far from seed sources.

     

Gametophytic self-incompatibility causes seedlessness in ‘Kagzi Kalan’ lemon (Citrus limon)

The present study aimed to study the flower and pollen structure, pollen viability, in vitro pollen germination of ‘Kagzi Kalan’ lemon (Citrus limon (L.) Osbeck), and in vivo pollen tube growth in self- and cross pollination to understand the mechanism of seedlessness. The results revealed that Kagzi Kalan had tetra-colporate spherical shaped pollen of uniform size. The results of Acetocarmine and FDA test and in vitro germination indicated normal pollen viability and germinability in Kagzi Kalan. In vivo pollen tube growth showed > 50% pollen germination on stigma in all treatments though a greater number of pollen tubes at the mid style, base of the style, and near the ovule was found in cross pollination. Contrary to this, despite optimum pollen germination (53.51–70.37%) in self-pollination treatments, none of the pollen tubes reached the base of the style due to abnormal growth of pollen tubes, viz. curvatures, inhibition of pollen tube growth, and callose deposition. The inhibition of pollen tubes at the mid style under self-pollination treatments, and production of seeded fruits under cross pollination treatments, indicate the presence of self-incompatibility and the site of inhibition of pollen tubes. Thus, gametophytic self-incompatibility (SI) caused seedlessness in Kagzi Kalan by blocking fertilization in the ovary.     

《Method in Fruit Breeding》(果树育种方法)一书简介

<正> 我们曾在《中国果树》1978年第1期上,以“对《果树育种进展》一书的评述”为题,介绍了美国 Purdue 大学1975年出版,由 Jules Janick 和James N.Moorc 等著的《Advances in FruitBreeding》。不久,我国许多学者先后翻译出版了其中的柑桔、苹果、梨、桃、李、杏、樱桃、葡萄、核桃和板栗等部分。该书以各论形式编写,分别论述了各树种的起源和早期发展、品种改良的历史、     

Studies in the Development of the Strawberry: III. Flower-Bud Initiation and Development in Large-Fruited Perpetual (“Remontant”) Strawberries

Summary

Four N application rates generated a range of tree N status as indicated by leaf N concentrations in six year old trees of `Mission' almond (Prunus dulcis (Mill.) D. A. Webb). Leaf N concentrations were related positively with concentrations of amino acids - especially asparagine and glutamine - in phloem and xylem saps. A pulse of 1.25 kg N per tree was applied to trees previously receiving 0, 78, 157 or 313 g N per tree, annually. Apparent uptake of soil N into above-ground tree parts was determined over a 39 d period. N uptake was determined as the difference in the products of tree biomass and tissue N concentrations before and after the N pulse. Tissue N concentrations increased signi®cantly in trees previously receiving the two lowest N application rates, whereas trees previously receiving the high N treatments were unresponsive. Tree N contents (0 g N per year, and also 78 g N per year treatments) increased slightly in response to the N pulse, although statistical differences were not observed due possibly to high variability in biomass among trees. At the same time, the amino acid concentrations in phloem exudate and xylem sap were highest in trees grown under the highest N fertilization regime. We suggest that the high amino acid concentrations in the phloem and xylem saps are indicative of a larger pool of amino N cycling throughout the vasculature of high N-status trees. Our data indicate an inverse relationship between tree N status, amino acid concentrations in xylem and phloem saps and capacity for soil N uptake in ®eld-grown trees. These results represent the ®rst ®eld data to correlate the concentration of amino acids circulating in the plant vasculature with soil N uptake. A functional relationship between the amino acid concentrations cycling within the tree and the regulation of soil N uptake has, however, not yet been established.     

Uneven ripening in ‘Bangalore blue’ grape (Vitis vinifera × Vitis labrusca) berries in India is linked to seed viability

Uneven ripening (UR) is a physiological disorder of unknown origin in ‘Bangalore blue’ grape (Vitis vinifera × Vitis labrusca) leading to wine of inferior quality. A preliminary study found wide variations in total dehydrogenase activity (TDH) of seeds from unevenly ripe berries. In our experiments, gibberellin (GA₃) applied to young grapes increased seed TDH activity and reduced the incidence of uneven ripening to 2% compared with 35% in the control. In contrast, paclobutrazol (PBZ) decreased TDH activity and increased the incidence of the disorder to 58%. GA₃-treated berries had higher concentrations of sucrose and TDH activity in seed representing mature seeds with high viability. In contrast, PBZ-treated and control berries had higher concentrations of glucose and lower TDH activity, indicating immature seeds with low viability. These results suggested that competition among developing berries can lead to differences in seed gibberellin content, seed viability and the rate of berry growth resulting in green, purple, and black berries at harvest. The study established the role of seed viability in uneven ripening and demonstrated that the incidence of the disorder is reduced by the application of GA₃ to immature berries.     

Lysophosphatidic acid (LPA) induces the proliferation of astrocytes in rat via pathway of protein kinase C-α and calcium ion in vitro

AIM: To determine if lysophosphatidic acid (LPA) regulates the proliferation of astrocytes (AS) and to approach the mechanism of the process.METHODS: The cerebral AS of the neonatal SD rats were cultured in vitro and divided randomly into control group, PKC excitomotor (PMA) group, LPA group, PKC-α inhibitor (Ro31-8220) group, Ro31-8220+PMA group and Ro31-8220+LPA group. The proliferation of the cells was detected by MTT assay and flow cytometry (FCM). The concentration of intra-cellular calcium ion of the cells (［Ca2＋］i) which were labeled with Fura-2/AM was determined by ultraviolet spectrophotometer. The change of PKC-α inside the cells was observed by Western blotting.RESULTS: LPA and PMA stimulated the proliferation of AS, they also enhanced the expression of PKC-α and increased the concentration of ［Ca2＋］i. After pretreated with Ro31-8220, the abilities of LPA that mentioned above were decreased. The change of ［Ca2＋］i was associated with the diversity of PKC-α.CONCLUSION: LPA promotes the proliferation of AS via the way of PKC-α and Ca2＋.     

The ‘habitat backbone’ as strategy to conserve pioneer species in dynamic port habitats: lessons from the natterjack toad (Bufo calamita) in the Port of Antwerp (Belgium)

Biodiversity conservation in economic areas like ports has recently become more important in the European Union due to a stricter interpretation of nature protection laws. In this study we develop a planning and design strategy—the ‘habitat backbone’—with which to support the long-term survival of pioneer species that occur in ports and have low dispersal abilities. For those species, long-term survival in port areas is uncertain because supply of their habitats (on vacant lots) is capricious and depends on land use dynamics. By gaining knowledge about spatial and temporal characteristics of these dynamics we were able to develop a solution to conserve such species. Our solution is based on the creation of permanent habitat—defined as a ‘backbone’—on (semi-) public land with an overall carrying capacity sufficient to support persistent populations. This best ensures long-term survival, and the backbone may also act as refugium. Satellite populations that emerge on adjacent vacant lots will thereby add to the persistence of the overall metapopulation. Management of permanent habitat is focused on retaining early-successional stages of vegetation. Implementing this strategy in the case of the natterjack toad in the Port of Antwerp taught us that realization of a habitat backbone is possible only if landowners, local governments and environmental NGOs cooperate. In the case at hand, such cooperation resulted in a plan that should ensure a coherent and persistent habitat network in which a chorus of some 1,400 natterjack toads could be accommodated—more than the number of toads currently observed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Drivers of grassland loss in Hungary during the post-socialist transformation (1987–1999)

The increase in the speed of land-cover change experienced worldwide is becoming a growing concern. Major socio-economic transitions, such as the breakdown of socialism in Europe, may lead to particularly high rates of landscape transformations. In this paper we examined the loss of semi-natural grasslands in Hungary between 1987 and 1999. We studied the relationship between 9 potential driving forces and the fate of grasslands using logistic GLMs. Grassland loss was found to be very high (1.31 % per year), which is far higher than either before or after this period. The most influential predictors of grassland loss were environmental and landscape characteristics (soil type, area of remnant grassland patches), and the socio-economic context (distance to paved road, and nearest settlement, human population density). Several processes and relationships can only be understood from a historical perspective (e.g. large extent of afforestation, strong decrease of soil water table). Grassland loss during the study period emerged as a consequence of survival strategies of individual farmers seeking adaptation to the changing environmental and socio-economic conditions, and not urbanization and agricultural intensification which are the main underlying drivers for the ongoing landscape transformations in most parts of the developed world. Though globalization increasingly influences local land use decisions, reconstructing and modelling recent landscape changes cannot be done without a proper understanding of local history and culture. Our analysis shows the importance of large-area yet high resolution landscape change research, which may reveal unexpected patterns of land cover change, undetected at coarser scales.     

Variation in nitrogen deposition and available soil nitrogen in a forest–grassland ecotone in Canada

Regional variation in nitrogen (N) deposition increases plant productivity and decreases species diversity, but landscape- or local -scale influences on N deposition are less well-known. Using ion-exchange resin, we measured variation of N deposition and soil N availability within Elk Island National Park in the ecotone between grassland and boreal forest in western Canada. The park receives regionally high amounts of atmospheric N deposition (22 kg ha⁻¹ yr⁻¹). N deposition was on average higher ton clay-rich luvisols than on brunisols, and areas burned 1–15 years previously received more atmospheric N than unburned sites. We suggest that the effects of previous fires and soil type on deposition rate act through differences in canopy structure. The magnitude of these effects varied with the presence of ungulate grazers (bison, moose, elk) and vegetation type (forest, shrubland, grassland). Available soil N (ammonium and nitrate) was higher in burned than unburned sites in the absence of grazing, suggesting an effect of deposition. On grazed sites, differences between fire treatments were small, presumably because the removal of biomass by grazers reduced the effect of fire. Aspen invades native grassland in this region, and our results suggest that fire without grazing might reinforce the expansion of forest into grassland facilitated by N deposition.     

Antagonisten und Pr?datoren der Maulbeerschildlaus Pseudaulacaspis pentagona (Targioni-Tozzetti, 1886) (Homoptera: Diaspididae) in Baden-W��rttemberg

Antagonists of the white scale (Pseudaulacaspis pentagona, Targioni-Tozzetti, 1886) were determined from peaches and sweet cherries as host plant at the orchards of the Centre for Agriculture and Technology Augustenberg (LTZ) in 2009 and 2010 as well as from four other commercial red and black currant orchards in Baden-Wuerttemberg in 2010. The study focused mainly on the parasitoid species of P. pentagona as well as the rate of parasitism of white scale caused by these parasitoids using emergence traps with invested branch samples of the different host plants in the laboratory. Beside the parasitoids, possible predators of the white scale were observed in the field in 2010 at the orchard of the LTZ. The two parasitic wasp species Aphytis diaspidis and Encarsia berlesei (Howard, 1881 and 1906) were determined as parasitoids of the white scale, whereas A. diaspidis was dominant at most sites. Rate of parasitism caused by both species ranged from 1.9 to 23.0%. The Kidney-Spot Ladybird Beetle (Chilocorus renipustulatus, Scriba, 1790) could be observed as a predator of the white scale in the field.     

Advances in mitochondria injury by Aβ in Alzheimer's disease

The β-amyloid protein (Aβ) has long been considered to associate with Alzheimers disease (AD). In addition, groups of evidence show that the soluble intracellular Aβ plays an important role in the disease development. The mitochondrial dysfunction induced by Aβ accumulation is a main pathologic process in early stage of AD. Matured Aβ is imported into the mitochondria through an unclear route. Once inside the mitochondria, Aβ is able to interact with a number of targets, including amyloid-binding alcohol dehydrogenase (ABAD) and cyclophilin D (CypD), which is a component of the mitochondrial permeability transition pore. Interference with the normal functions of these proteins results in mitochondrial injury, such as energy dyshomeostasis, production of reactive oxygen species, membrane permeability alteration and so on. This review explores the Aβ generation and location in mitochondria. The mitochondrial injury induced by the interaction between Aβ and its targets are also discussed.     

Premature seed germination induced by very-long-chain fatty acids causes jelly seed disorder in the mango (Mangifera indica L.) cultivar ‘Amrapali’ in India

Jelly seed (JS) in ‘Amrapali’ mango (Mangifera indica L.) is a physiological disorder, the cause of which has long remained obscure. The disorder is distinguished by the appearance of jelly-like tissue in the pulp adjoining the stone, although the fruit show no external symptoms. The objective of this study was to determine the causative factor inducing the JS disorder in ‘Amrapali’ mango. Studies showed, for the first time, that JS in ‘Amrapali’ mango arose at the start of germination-associated events in the seed of developing fruit. The trigger for premature seed germination originated from reduced synthesis of very-long-chain fatty acids (VLCFAs) in the seed of developing fruit. This then promoted the production of cytokinins, leading to the onset of premature germination-associated events in the seed. Consequently, a large increase in the activities of pectinolytic enzymes in JS pulp occurred that led to the rapid degradation of pectin and excessive softening of the pulp, to the consistency of jelly. The application of plant growth regulators to developing fruit showed that gibberellic acid (GA₃) increased the incidence of JS, while paclobutrazol reduced the incidence of JS, confirming that the onset of early germination during fruit maturation and ripening played a primary role in the incidence of the JS disorder.