The efficacy of soil ameliorants to improve early establishment in trees and shrubs in degraded Eucalyptus gomphocephala woodlands

2012 ◽  
Vol 18 (4) ◽  
pp. 310 ◽  
Author(s):  
Katinka X Ruthrof ◽  
Tegan K Douglas ◽  
Michael C Calver ◽  
Michael D Craig ◽  
Bernard Dell ◽  
...  
Keyword(s):  
Seedling Establishment ◽  
Survival Rates ◽  
Field Trials ◽  
Establishment Success ◽  
Wide Range ◽  
Early Seedling ◽  
Study Sites ◽  
Eucalyptus Gomphocephala ◽  
Nutrient Resources ◽  
Early Establishment

Many Mediterranean-type ecosystems (MTEs) are now vulnerable to climate change, with some regions predicted to undergo a shift towards much drier and hotter conditions. Although MTE woodlands are highly resilient to periods of drought and perturbations such as fire, this shift increases the already wide range of threatening processes they face. Without intervention, such as revegetation, many of these woodlands could degrade to the point where they support little of the original biota. However, in MTEs with hard to predict breaks in the season and nutrient poor soils; seedling establishment success is often very low. Using degraded Eucalyptus gomphocephala woodlands as a case study, we undertook two field trials with five commercially available plant treatments to evaluate their effectiveness in increasing early seedling establishment. We found that the mere addition of seedlings may not be enough to undertake successful revegetation in some degraded woodlands because a) survival rates in controls were, on average 53% at one of the study sites and b) the supplementation of nutrient resources beneath the rootball when planting increased early seedling growth and health compared with other treatments. We suggest that under emerging and well-recognized challenges to revegetation, supplementing abiotic resources, in particular nutrients applied exclusively beneath planted seedlings, may increase early establishment success.

scholarly journals Cotyledon integrity on Anadenanthera colubrina (vell.) brenan (fabaceae - mimosoideae) germination and early establishment

CERNE ◽  
2010 ◽  
Vol 16 (2) ◽  
pp. 227-264
Author(s):  
Hisaias de Souza Almeida ◽  
Anne Priscila Dias Gonzaga ◽  
Helaine de Sousa ◽  
Yule Roberta Ferreira Nunes ◽  
Henrique Nery Cipriani
Keyword(s):  
Seed Germination ◽  
Seedling Establishment ◽  
Seedling Survival ◽  
Early Growth ◽  
Forest Species ◽  
Growth Reduction ◽  
Early Seedling ◽  
Growth Of Seedlings ◽  
Early Establishment

Despite the major ecological and economical relevance of forest species, little is known about their seedling establishment and seed germination, as well as the damage effects to seeds at these stages. This work aimed to assess the effects of partial cotyledon loss on the seed germination and early seedling establishment of Anadenanthera colubrina. Therefore, whole (control) and split seeds (with ¹/8, ¹/4, and ½ of their size cut) were evaluated. The seeds were then germinated and the early growth of seedlings was assessed. The treatments had no effect on seed germination, however, they influenced seedling survival and establishment. The highest mortality and growth reduction values were obtained with the most severe cotyledon removal. This indicates that the tegument and the partial cotyledon loss do not represent a barrier against seed germination. However, considerable damages may be detrimental to establishment and survival of A. colubrina seedlings.

Early Establishment of Photosynthesis and Auxin Biosynthesis Plays a Key Role in Early Biomass Heterosis in Brassica napus (Canola) Hybrids

2020 ◽  
Vol 61 (6) ◽  
pp. 1134-1143
Author(s):  
Anyu Zhu ◽  
Aihua Wang ◽  
You Zhang ◽  
Elizabeth S Dennis ◽  
W James Peacock ◽  
...  
Keyword(s):  
Brassica Napus ◽  
Plant Development ◽  
Seedling Establishment ◽  
Hybrid Vigor ◽  
Auxin Biosynthesis ◽  
Expression Of Genes ◽  
Early Expression ◽  
Early Seedling ◽  
Palisade Cells ◽  
Early Establishment

Abstract Heterosis or hybrid vigor has been used widely for more than a decade in Canola (Brassica napus) production. Canola hybrids show heterosis in a variety of traits compared to parents, including increased biomass at the early stages of seedling establishment, which is a critical developmental step that impacts future plant growth and seed yield. In this study, we examined transcriptomes of two parental lines, Garnet (Gar) and NX0052 (0052), and their reciprocal hybrids, Gar/0052, at 4 and 8 days after sowing (DAS). In hybrids, early seedling biomass heterosis is correlated with earlier expression of genes in photosynthesis pathways relative to parents. The hybrids also showed early expression of genes in the auxin biosynthesis pathway, consistent with the higher auxin concentrations detected in hybrid seedlings at 4 DAS. Auxin is a key phytohormone that regulates plant development promoting cell expansion and cell proliferation. Consistent with the increased levels of auxin, hybrids have larger and more palisade cells than the parents at the same time point. We propose a possible mechanism of early biomass heterosis through the early establishment of photosynthesis and auxin biosynthesis, providing insights into how transcriptional changes in hybrids are translated into phenotypical heterosis. This finding could be utilized in future Canola breeding to identify hybrid combinations with the superior early seedling establishment and strong levels of hybrid vigor in later plant development.

scholarly journals Imidacloprid seed treatments for the control of springtails in seedling brassicas

2002 ◽  
Vol 55 ◽  
pp. 317-321 ◽  
Author(s):  
P.J. Addison ◽  
P.W. Fisher
Keyword(s):  
Adverse Effect ◽  
Seedling Growth ◽  
Seedling Establishment ◽  
Seed Treatment ◽  
Field Trials ◽  
Seed Treatments ◽  
Early Seedling Growth ◽  
Pot Trials ◽  
Early Seedling

Two pot trials and two field trials were conducted to evaluate imidacloprid seed treatments for springtail control in forage brassica seedlings Imidacloprid at rates from 175 to 210 g ai/kg seed reduced garden springtail (Bourletiella hortensis) and lucerne flea (Sminthurus viridis) numbers by 6888 relative to the untreated controls Springtail damage was reduced and seedling establishment enhanced Imidacloprid proved as or more effective than furathiocarb or thiodicarb seed treatments and phorate granules Imidacloprid seed treatment had no adverse effect on either brassica germination or early seedling growth

Grain mineral density of bread and durum wheat landraces from geochemically diverse native soils

2018 ◽  
Vol 69 (4) ◽  
pp. 335 ◽  
Author(s):  
José Francisco Vázquez ◽  
Efraín Antonio Chacón ◽  
José María Carrillo ◽  
Elena Benavente
Keyword(s):  
Durum Wheat ◽  
Triticum Aestivum L ◽  
Field Trials ◽  
Mineral Elements ◽  
Small Scale ◽  
Mineral Density ◽  
Native Soil ◽  
Wide Range ◽  
Grain Zinc ◽  
Wheat Landraces

Future progress on the creation of wheat cultivars with high grain zinc (Zn) and iron (Fe) mineral density will depend on both the availability of suitable donor germplasm and the identification of genes or quantitative trait loci contributing to increase the accumulation of mineral elements in the wheat kernels. Multi-environment field trials were conducted to evaluate the grain Zn, Fe and protein concentration of 32 bread wheat (Triticum aestivum L.) and 20 durum wheat (T. turgidum L. var. durum) landraces locally adapted to soils covering a wide range of pH values and mineral composition. These landraces were selected after a preliminary, small-scale field trial that had analysed 425 Spanish local varieties. Analyses of variance demonstrated a significant effect of genotype on grain composition, and 16 wheat landraces with elevated grain Zn and/or Fe density across the environments were identified. These landraces rich in grain minerals represent valuable primary gene-pool parents for wheat biofortification. No pattern of native soil geochemical characteristics that could help to predict the success in collecting mineral-dense genotypes in a given area was found. Mapping populations derived from some pairs of grain-mineral-rich and -poor genotypes characterised in the study may facilitate the development of molecular markers to assist the selection of superior wheat genotypes.

scholarly journals In-field screening for host plant resistance to Delia radicum and Brevicoryne brassicae within selected rapeseed cultivars and new interspecific hybrids

2020 ◽  
Vol 15 (1) ◽  
pp. 711-720
Author(s):  
Janetta Niemann ◽  
Justyna Szwarc ◽  
Jan Bocianowski ◽  
Dorota Weigt ◽  
Marek Mrówczyński
Keyword(s):  
Life Sciences ◽  
Field Trials ◽  
Brevicoryne Brassicae ◽  
Delia Radicum ◽  
Sources Of Resistance ◽  
Cabbage Aphid ◽  
Hybrid Combination ◽  
Resistance To Insects ◽  
Wide Range ◽  
High Level

AbstractRapeseed (Brassica napus) can be attacked by a wide range of pests, for example, cabbage root fly (Delia radicum) and cabbage aphid (Brevicoryne brassicae). One of the best methods of pest management is breeding for insect resistance in rapeseed. Wild genotypes of Brassicaceae and rapeseed cultivars can be used as a source of resistance. In 2017, 2018, and 2019, field trials were performed to assess the level of resistance to D. radicum and B. brassicae within 53 registered rapeseed cultivars and 31 interspecific hybrid combinations originating from the resources of the Department of Genetics and Plant Breeding of Poznań University of Life Sciences (PULS). The level of resistance varied among genotypes and years. Only one hybrid combination and two B. napus cultivars maintained high level of resistance in all tested years, i.e., B. napus cv. Jet Neuf × B. carinata – PI 649096, Galileus, and Markolo. The results of this research indicate that resistance to insects is present in Brassicaceae family and can be transferred to rapeseed cultivars. The importance of continuous improvement of rapeseed pest resistance and the search for new sources of resistance is discussed; furthermore, plans for future investigations are presented.

scholarly journals Efficacy of Brentuximab Vedotin in Relapsed or Refractory High-CD30–Expressing Non-Hodgkin Lymphomas: Results of a Multicenter, Open-Labeled Phase II Trial

2020 ◽  
Vol 52 (2) ◽  
pp. 374-387 ◽  
Author(s):  
Seok Jin Kim ◽  
Dok Hyun Yoon ◽  
Jin Seok Kim ◽  
Hye Jin Kang ◽  
Hye Won Lee ◽  
...  
Keyword(s):  
Treatment Outcome ◽  
Disease Control ◽  
Phase Ii ◽  
Single Agent ◽  
Survival Rates ◽  
Sensory Neuropathy ◽  
Large Cell ◽  
Brentuximab Vedotin ◽  
Disease Control Rate ◽  
Wide Range

PurposeThe treatment outcome of brentuximab vedotin (BV) has not been related with CD30 expression in previous studies enrolling patients with a wide range of CD30 expression level. Thus, this study explored the efficacy of BV in high-CD30–expressing non-Hodgkin lymphoma (NHL) patients most likely to benefit.Materials and MethodsThis phase II study (Clinicaltrials.gov: NCT02280785) enrolled relapsed or refractory high-CD30–expressing NHL, with BV administered intravenously at 1.8 mg/kg every 3 weeks. The primary endpoint was > 40% disease control rate, consisting of complete response (CR), partial response (PR), or stable disease. We defined high CD30 expression as ≥ 30% tumor cells positive for CD30 by immunohistochemistry.ResultsHigh-CD30-expressing NHL patients (n=33) were enrolled except anaplastic large cell lymphoma. The disease control rate was 48.5% (16/33) including six CR and six PR; six patients (4CR, 2PR) maintained their response over 16 completed cycles. Response to BV and survival were not associated with CD30 expression levels. Over a median of 29.2 months of follow-up, the median progression-free and overall survival rates were 1.9 months and 6.1 months, respectively. The most common adverse events were fever (39%), neutropenia (30%), fatigue (24%), and peripheral sensory neuropathy (27%). In a <i>post-hoc</i> analysis for the association of multiple myeloma oncogene 1 (MUM1) on treatment outcome, MUM1- negative patients showed a higher response (55.6%, 5/9) than MUM1-positive patients (13.3%, 2/15).ConclusionBV performance as a single agent was acceptable in terms of disease control rates and toxicity profiles, especially MUM1-negative patients.

EARLY SEEDLING VIGOUR AND SEED WEIGHT IN RELATION TO BREEDING IN SMOOTH BROMEGRASS, BROMUS INERMIS LEYSS.

1960 ◽  
Vol 40 (2) ◽  
pp. 268-280 ◽  
Author(s):  
W. E. Tossell
Keyword(s):  
Seed Weight ◽  
Field Trials ◽  
Bromus Inermis ◽  
Rapid Progress ◽  
Initial Screening ◽  
Agronomic Characters ◽  
Smooth Bromegrass ◽  
Seedling Vigour ◽  
Close Relationship ◽  
Early Seedling

Variability in early seedling vigour was studied in polycross progenies from highly selected plants rated as good in other agronomic characters and in open-pollinated progenies from previously unselected So plants. Differences were found in both groups in rate and per cent emergence, and in height and vigour at 28 days. Considering the variability observed in these characters and the favourable associations found, it appears that early seedling vigour in bromegrass can be improved by selection within the species.Seed weight was closely associated with early seedling vigour. Plants differed widely in seed weight, and in breeding for early seedling vigour it appears that most rapid progress can be made by screening breeding material for seed weight. Because seed weight did not account for all of the differences among progenies in seedling vigour, progenies from high seed weight plants or families should be subjected to a seedling vigour test to further select for this character. The close relationship found between greenhouse and field trials indicates that at least the initial screening can be done in the greenhouse.

What geckos are – an ecological-biogeographic perspective

2019 ◽  
Vol 66 (3-4) ◽  
pp. 253-263 ◽  
Author(s):  
Shai Meiri
Keyword(s):  
Survival Rates ◽  
Large Degree ◽  
Body Temperatures ◽  
Similar Activity ◽  
Wide Range ◽  
Low Latitudes ◽  
Preferred Temperatures ◽  
Biological Attributes ◽  
Globally Distributed ◽  
Activity Times

Geckos are a hyper-diverse, ancient, and globally distributed group. They have diverged early from other squamates and thus can be expected to differ from them along multiple ecological, life history, and biogeographic axes. I review a wide range of gecko traits, comparing them to those of other lizard taxa, to identify the unique, and unifying, attributes of geckos among lizards, based on comprehensive databases of lizard distributions and biological attributes. Few traits completely separate geckos from other lizard taxa, yet they differ to a large degree along many axes: they are more restricted to low latitudes and altitudes, are especially diverse on islands, but relatively scarce in America. They are small lizards, that lay small, fixed clutch sizes, for which they compensate only partially by laying frequently. Because they mature at relatively similar ages and have similar lifespans to other lizards, geckos produce fewer offspring over a year, and over their lifetimes, perhaps implying that they enjoy higher survival rates. While being the only large lizard clade of predominantly nocturnal lizards a large proportion of species is active by day. Gecko body temperatures and preferred temperatures are lower than those of other lizards –even when they are compared to lizards with similar activity times. Worryingly, most geckos have small ranges that often reside completely outside of protected areas – much more frequently than in other reptile and vertebrate taxa.

Geographic Variation in Habitat Structure of the Black-Throated Green Warbler (Dendroica virens)

The Auk ◽  
1983 ◽  
Vol 100 (2) ◽  
pp. 382-389 ◽  
Author(s):  
Scott L. Collins
Keyword(s):  
New York ◽  
Plant Community ◽  
Habitat Structure ◽  
Habitat Management ◽  
Principal Component ◽  
Structural Features ◽  
Wide Range ◽  
White Mountain National Forest ◽  
Study Sites ◽  
Regional Analyses

Abstract Habitat structure of the Black-throated Green Warbler (Dendroica virens) was examined at five study sites: (1) Mount Desert Island, Maine; (2) Mount Blue State Park, Maine; (3) White Mountain National Forest, New Hampshire; (4) southern Adirondacks, New York; and (5) Itasca State Park, Minnesota. Principal component analysis of 13 habitat-structure variables measured at each site produced habitat gradients from tall to shorter canopies, large to smaller trees, and coniferous to deciduous forests. A second ordination indicated that the habitat sampled included five plant-community types: pine forests, spruce-arbor vitae, balsam fir, mixed spruce-fir-deciduous, and beech-maple-birch. Consistent structural features within the total range of habitats sampled were difficult to identify. I suggest that widely occurring species such as the Black-throated Green Warbler have a wide range of habitats with a suitable structure and that regional analyses, even within a single plant-community type, may be of limited value with regard to habitat management when considering the entire range of many species.

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