scholarly journals Seed Productivity of Epipactis atrorubens (Hoffm.) Besser (Orchidaceae, Liliopsida) on the Northern Border of its Distribution Area

2020 ◽  
pp. 191-208
Author(s):  
I. A. Kirillova ◽  
D. V. Kirillov
Keyword(s):  
Komi Republic ◽  
Limiting Factors ◽  
Distribution Area ◽  
Anthropogenic Factors ◽  
Limiting Factor ◽  
Ural Mountains ◽  
Seed Productivity ◽  
Northeast Russia ◽  
Reproductive Characteristics ◽  
Northern Border

The Orchids due to their biological features, high decorative properties and poor resistance against anthropogenic factors are one of the most vulnerable components in vegetation of the world. Their conservation cannot be efficient without the knowledge on their reproductive biology. These data are especially important for species on the borders of their distribution area with additional reproduction limiting factors. Our study object is a rare orchid species Epipactis atrorubens (Hoffm.) Besser. During field works on the territory of the Komi Republic (northeast Russia), we studied 50 populations of E. atrorubens. Reproductive characteristics (fruit set, seed productivity and seed morphometry) were studied in 19 of them. We established that the main limiting factor in the North is a short vegetation period. Frosts damage generative shoots and do not allow seeds to ripe. The capsule of E. atrorubens on the northern distribution border contains fewer seeds than in the central part of areal. Also less is the indicator of real seed productivity. Within the Komi Republic on sample of two sites (the Timan Range and the Ural Mountains), we also see the decrease in all reproductive characteristics from south to north: the number and size of flowers, the number and quality of seeds decrease, their shape changes. However deterioration in seed productivity is compensated by an increase in seed volume. The populations of less than 50 shoots, in which juvenile plants are not marked, are in critical condition.

scholarly journals Dactylorhiza incarnata (L.) Soó (Orchidaceae, Liliopsida) on the northern border of its distribution area: Population structure and seed productivity

2021 ◽  
pp. 272-292
Author(s):  
I. A. Kirillova ◽  
D. V. Kirillov
Keyword(s):  
Population Structure ◽  
Flowering Time ◽  
Population Biology ◽  
Seed Quality ◽  
Komi Republic ◽  
Average Density ◽  
Distribution Area ◽  
Seed Productivity ◽  
North East ◽  
Northern Border

The results of the study of the population biology of the rare orchid Dactylorhiza incarnata (L.) Soó on the territory of the Komi Republic (north-east of European Russia), where the species is located on the northern border of its range, are presented. Data on the population structure, morphometric features of plants, and reproductive characteristics of the species are given. It was found that the size of plants and the number of flowers in the inflorescence of this species in the region is lower than in the more southern parts of its range. The populations size ranges from 30 to 350 individuals with their average density of 0.7–3.7 per 1 m2 , and it is common for this species in other parts of its distribution area. Reproductive success is associated with the weather of the second decade of June because the flowering time of the species in the region happens in this time. It was found that the seed size of D. incarnata (0.55×0.20 mm) on its northern border is smaller than in other parts of the range. The seed productivity is rather high: one fruit contains an average of 6.2 thousands of seeds and one individual could produce about 49.4 thousands of seeds. Temperature during flowering time and precipitation during seed ripening may affect seed quality. The presence of juvenile individuals (%) in all the studied populations shows seed recruitment in populations of this species at the northern limit of the range, despite a lower seed set in comparison with southern populations. 

scholarly journals Fertilization the Omission One Test as Determination Limiting Factors for Maize Biomass (Zea mays L.)

2021 ◽  
Vol 4 (2) ◽  
pp. 94-105
Author(s):  
Koko Tampubolon ◽  
Bagus Fitra Azmi ◽  
Perdana Andriano Tamba ◽  
Ayu Widya Lestari ◽  
Kamaruddin Kamaruddin ◽  
...  
Keyword(s):  
Plant Height ◽  
Leaf Growth ◽  
Block Design ◽  
Relative Yield ◽  
Animal Husbandry ◽  
Dry Weight ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Test Technique ◽  
The Impact

Introduction: The research was aimed to obtain information on the impact of omission one test fertilization as a determination limiting factors for the growth and biomass of maize in variety Bonanza F1. Materials and Methods: The research was located in the experimental field, Faculty of Agriculture and Animal Husbandry, Universitas Tjut Nyak Dhien, Medan from December 2020 until February 2021. The research was applied by Randomized Block Design in non-factorial through fertilization of omission one test that has been converted (urea : SP-36 : KCl = 0.75 : 0.50 : 0.125 g polybag-1). The treatment of this research include P0 = non-fertilization; P1= N+P+K; P2= P+K; P3= N+K; P4= N+P using three replications. The parameters include plant height, leaf growth, total fresh weight, total dry weight, and the percentage of relative yield then processed using ANOVA and continued with DMRT at 5% ± standard error with SPSS v.20 software. Results: Informed that the omission one test technique significantly improved all the characteristics of maize in the variety Bonanza F1. The highest increase in plant height was found in the N+P of 83.65%, meanwhile, the highest leaf and biomass growth characters were found in N+P+K, ranged of 50.00 to 177.81% and 487.60 to 507.37%, respectively. It was obtained that the limiting factor for the maize growth in variety Bonanza F1 was found in the un-fertilization of nitrogen.

scholarly journals APLIKASI SIG UNTUK PENETAPAN KESESUAIAN WILAYAH PENERAPAN MEKANISASI PERTANIAN TANAMAN PANGAN

2016 ◽  
Vol 10 (1) ◽  
pp. 31
Author(s):  
Mubekti Mubekti
Keyword(s):  
Remote Sensing ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Physical Parameters ◽  
Know How ◽  
Agricultural Mechanization ◽  
Preliminary Research

The study is the preliminary research aiming to apply the usefulness of the GISsystem for classifying suitability of region to the agricultural mechanization. Simplebasic theory of GIS and classification of agricultural mechanization were presented.Nine physical and non-physical parameters as limiting factors were defined and aweight of each parameter was calculated in order to know how far its effect to theagricultural mechanization practice. Data coming from several types, ie: numeric,vector and remote sensing (raster) were prepared to support the process. Twoordoes consisting of five classes were employed to extract suitability classificationof each District in Jawa Barat dan Banten Province. The results show that tendistricts are classified into suitable for applying agricultural mechanization, and therest ten districts are classified into not suitable. Depending on the dynamic characterof limiting factor, suitability class would possibly change along the time. Saveralconclusions and advices for improving research are given.

scholarly journals Potential Distribution of Six North American Higher-Attine Fungus-Farming Ant (Hymenoptera: Formicidae) Species

2019 ◽  
Vol 19 (6) ◽  
Author(s):  
Sarah F Senula ◽  
Joseph T Scavetta ◽  
Joshua A Banta ◽  
Ulrich G Mueller ◽  
Jon N Seal ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Species Distribution ◽  
Evolutionary History ◽  
Niche Overlap ◽  
The United States ◽  
Flood Frequency ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Soil Variables ◽  
Precipitation Seasonality

Abstract Ants are among the most successful insects in Earth’s evolutionary history. However, there is a lack of knowledge regarding range-limiting factors that may influence their distribution. The goal of this study was to describe the environmental factors (climate and soil types) that likely impact the ranges of five out of the eight most abundant Trachymyrmex species and the most abundant Mycetomoellerius species in the United States. Important environmental factors may allow us to better understand each species’ evolutionary history. We generated habitat suitability maps using MaxEnt for each species and identified associated most important environmental variables. We quantified niche overlap between species and evaluated possible congruence in species distribution. In all but one model, climate variables were more important than soil variables. The distribution of M. turrifex (Wheeler, W.M., 1903) was predicted by temperature, specifically annual mean temperature (BIO1), T. arizonensis (Wheeler, W.M., 1907), T. carinatus, and T. smithi Buren, 1944 were predicted by precipitation seasonality (BIO15), T. septentrionalis (McCook, 1881) were predicted by precipitation of coldest quarter (BIO19), and T. desertorum (Wheeler, W.M., 1911) was predicted by annual flood frequency. Out of 15 possible pair-wise comparisons between each species’ distributions, only one was statistically indistinguishable (T. desertorum vs T. septentrionalis). All other species distribution comparisons show significant differences between species. These models support the hypothesis that climate is a limiting factor in each species distribution and that these species have adapted to temperatures and water availability differently.

scholarly journals Evaluation of survival and growth of Picea abies (L.) H. Karst. and Picea obovata Ledeb. provenances in the north of Russia

2017 ◽  
Vol 63 (No. 9) ◽  
pp. 401-407
Author(s):  
Nakvasina Elena N ◽  
Demina Nadezhda A ◽  
Prozherina Nadezhda A
Keyword(s):  
Picea Abies ◽  
Komi Republic ◽  
Climatic Conditions ◽  
Russian Plain ◽  
Distribution Area ◽  
Picea Obovata ◽  
Ecological Plasticity ◽  
The North ◽  
Provenance Trials ◽  
Hybrid Forms

Adaptation variability and ecological plasticity in the “genotype-environment” system of 22 provenances of Picea abies (Linnaeus) H. Karsten, Picea obovata (von Ledebour) and their introgressive hybrids growing within the Russian Plain were studied. Provenances grow in provenance trials located in the Arkhangelsk, Vologda Regions, and Komi Republic. For assessment of provenances in the “genotype-environment” system, the ranking method was used. Based on a complex ranking index (survival, diameter, height) two local areas of the most adaptive geographic races of P. abies, P. obovata and their hybrid forms were distinguished. In the south-western part of the Russian Plain the best provenances are represented by P. abies and related hybrids from Karelia, Vologda, Leningrad, and Pskov Regions. In the north-eastern part they are represented by P. obovata and its hybrids from the Komi Republic, Arkhangelsk, Sverdlovsk Regions. Provenances of local P. abies and related hybrid forms demonstrate high ecological plasticity on their growing in harsh climatic conditions of the north outside of the species distribution area.

scholarly journals Impact of the COVID-19 Epidemic on Stroke Care and Potential Solutions

Stroke ◽  
2020 ◽  
Vol 51 (7) ◽  
pp. 1996-2001 ◽  
Author(s):  
Jing Zhao ◽  
Hang Li ◽  
David Kung ◽  
Marc Fisher ◽  
Ying Shen ◽  
...  
Keyword(s):  
Big Data ◽  
Hospital Admissions ◽  
Stroke Care ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Significant Drop ◽  
The Public ◽  
Key Factor ◽  
Prehospital Delays ◽  
The Impact

Background and Purpose: When the coronavirus disease 2019 (COVID-19) outbreak became paramount, medical care for other devastating diseases was negatively impacted. In this study, we investigated the impact of the COVID-19 outbreak on stroke care across China. Methods: Data from the Big Data Observatory Platform for Stroke of China consisting of 280 hospitals across China demonstrated a significant drop in the number of cases of thrombolysis and thrombectomy. We designed a survey to investigate the major changes during the COVID-19 outbreak and potential causes of these changes. The survey was distributed to the leaders of stroke centers in these 280 hospitals. Results: From the data of Big Data Observatory Platform for Stroke of China, the total number of thrombolysis and thrombectomy cases dropped 26.7% ( P <0.0001) and 25.3% ( P <0.0001), respectively, in February 2020 as compared with February 2019. We retrieved 227 valid complete datasets from the 280 stroke centers. Nearly 50% of these hospitals were designated hospitals for COVID-19. The capacity for stroke care was reduced in the majority of the hospitals. Most of the stroke centers stopped or reduced their efforts in stroke education for the public. Hospital admissions related to stroke dropped ≈40%; thrombolysis and thrombectomy cases dropped ≈25%, which is similar to the results from the Big Data Observatory Platform for Stroke of China as compared with the same period in 2019. Many factors contributed to the reduced admissions and prehospital delays; lack of stroke knowledge and proper transportation were significant limiting factors. Patients not coming to the hospital for fear of virus infection was also a likely key factor. Conclusions: The COVID-19 outbreak impacted stroke care significantly in China, including prehospital and in-hospital care, resulting in a significant drop in admissions, thrombolysis, and thrombectomy. Although many factors contributed, patients not coming to the hospital was probably the major limiting factor. Recommendations based on the data are provided.

scholarly journals The TATA-binding protein is not an essential target of the transcriptional activators Gal4p and Gcn4p in Saccharomyces cerevisiae

2003 ◽  
Vol 370 (1) ◽  
pp. 141-147 ◽  
Author(s):  
Christine BONGARDS ◽  
Boon Shang CHEW ◽  
Norbert LEHMING
Keyword(s):  
Transcriptional Activation ◽  
Binding Protein ◽  
Tata Binding Protein ◽  
Limiting Factors ◽  
Clear Correlation ◽  
Limiting Factor ◽  
Local Concentration ◽  
Transcriptional Activators ◽  
Transcription Process

According to the recruitment model, transcriptional activators work by increasing the local concentration of one or several limiting factors for the transcription process at the target promoter. The TATA-binding protein Tbp1 has been considered as a likely candidate for such a limiting factor. We have used a series of Gal4p and Tbp1 mutants to correlate the in vivo interaction between the two proteins with the strength of activation. We find a clear correlation between activation strength and in vivo interaction for the series of Gal4p mutants. Consistently, the weaker activator Gcn4p does not interact with Tbp1. However, a corresponding analysis of the series of Tbp1 mutants revealed that Tbp1 is not an essential target of the acidic activators Gal4p and Gcn4p. Furthermore, detailed analysis of a Tbp1 mutant deficient for transcriptional activation by Gal4p revealed that the mutant is defective in interactions with five other proteins involved in the process of transcription.

KARAKTERISTIK DAN PRODUKTIVITAS LAHAN SAWAH IRIGASI DI KECAMATAN DUAMPANUA KABUPATEN PINRANG

2019 ◽  
Vol 8 (1) ◽  
pp. 34
Author(s):  
Rachmad Wunangkolu ◽  
Rismaneswati Rismaneswati ◽  
Christianto Lopulisa
Keyword(s):  
Nutrient Retention ◽  
Exchange Capacity ◽  
Land Suitability ◽  
Base Saturation ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Silty Clay ◽  
Field Surveys ◽  
Observation Units ◽  
Average Rainfall

Land potential can be assessed from biophysical land suitability including soil characteristics, climate, and land management. This study aims to determine the potential of paddy fields in Duampanua Sub-District, Pinrang District for irrigated paddy field based on the land biophysical characteristics. The method was qualitative and quantitative approaches. Field surveys use purposive sampling method with 3 object observation. The land suitability class evaluation uses a simple limiting factor approach according to FAO (1976). To support the analysis of rice production data, 30 farmers were interviewed in 3 (three) observation units. The results showed the average rainfall of 2,780.2 mm/year with 9 wet months and 3 dry months categorized as type B2 (Oldeman). The results of soil samples analysis showed the characteristics of the soil with a silty clay texture, silty clay loam and clay; bulk density ranges from 1.36-1.66 g/cm3; cation exchange capacity ranges from 49.64 - 79.75 cmol/kg clay; soil pH ranges from 5.26-5.97; base saturation ranges from 36% - 46.4%; and C-organic ranges from 1.34% - 1.38%. The most dominant types of minerals are orthoclase, biotite, pyroxene, augite, opaque and clay with the symptoms of micropedological concretions and nodules. The land suitability class in the three land units for irrigated paddy rice is classified as S2nr (quite suitability in accordance with the limiting factors for nutrient retention including: base saturation, pH, and C-organic). The average productivity in land units I is 5.1 ton/ha, land unit II is 4.5 ton/ha, and in land units III 5.26 ton/ha.

What are the limiting factors related to discontinuance of chemotherapy after failure of first-line S-1 plus CDDP in Japanese patients with advanced gastric cancer?

2012 ◽  
Vol 30 (4_suppl) ◽  
pp. 149-149
Author(s):  
Yoshihito Ohhara ◽  
Keisho Chin ◽  
Mariko Ogura ◽  
Mitsukuni Suenaga ◽  
Eiji Shinozaki ◽  
...  
Keyword(s):  
Multivariate Analyses ◽  
Japanese Patients ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Second Line ◽  
First Line ◽  
Second Line Chemotherapy ◽  
Group A ◽  
To Receive ◽  
Line Chemotherapy

149 Background: Recently, it is suggested that second-line chemotherapy improved survival in advanced gastric cancer (AGC) and it is commonly performed in Japanese daily practice in these several years. We investigated the limiting factor not to be able to receive second-line chemotherapy in Japanese patients with AGC. Methods: Between 2007 and 2009, 155 patients received S-1 plus cisplatin (SP) treatment as first-line chemotherapy in Cancer Institute Hospital of JFCR, Japan. Among them, 148 patients could not continue SP treatment because of disease progression or unacceptable toxicity. 109 patients could receive second-line chemotherapy (Group A), while 39 patients could not (Group B). We evaluated the clinicopathologic factors that affected not to receive second-line chemotherapy, retrospectively. Univariate and multivariate analyses were performed on the baseline factors before starting first-line chemotherapy. Results: Characteristics of patients were below (Group A vs B): median age, 60 vs 66 (years); gender (male), 71.6 % vs 66.7 %. Median progression-free survival were not different in both Group statistically (6.5 vs 7.2 months; log-rank, p=0.861). Median overall survival were 16.5 vs 10.3 months (log-rank, p<0.001), respectively. Univariate analyses found 4 limiting factors not to initiate second-line chemotherapy: age over 65 years old (p=0.025), performance status>1 (p=0.017), alkaline phosphatase (ALP) >400 IU/l (p<0.001), C-reactive protein (CRP) >1.0 mg/dl (p=0.004). Multivariate analyses showed ALP elevation was a limiting factor (HR 4.122, p=0.003). Conclusions: Alkaline phosphatase can be an uncomplicated and potent limiting factor of discontinuance of chemotherapy after failure of the first line S-1 plus CDDP in Japanese patients with AGC.

Reproductive characteristics of the Pyrenean high-mountain lizards: Iberolacerta aranica (Arribas, 1993), I. aurelioi (Arribas, 1994) and I. bonnali (Lantz, 1927)

2005 ◽  
Vol 55 (2) ◽  
pp. 163-190 ◽  
Author(s):  
Pedro Galán ◽  
Oscar Arribas
Keyword(s):  
Clutch Size ◽  
Reproductive Cycle ◽  
Reproductive Potential ◽  
Activity Cycle ◽  
Field Studies ◽  
Climatic Conditions ◽  
Distribution Area ◽  
High Mountain ◽  
Time Data ◽  
Reproductive Characteristics

AbstractThe three lacertid lizards species of the Iberolacerta genus, which have recently been described or recognised as different species, are reptiles that live strictly at the highest altitudes in Europe, from elevations of near 1900 up to more than 3000 m a.s.l. in the Pyrenees (Spain, Andorra, France). In this paper, the reproductive cycle and reproductive characteristics of these species are described for the first time. Data were obtained from field studies carried out in different high-mountain Pyrenean locations from 1989–2002. In addition we also conducted hatching studies in laboratory. Due to the harsh climatic conditions in the high mountains the activity cycle of these species is very short, just over 4 months, from mid-May to late September or beginning of October. This affects their reproductive cycle (i.e., only one annual egg-clutch is produced), as well as other reproductive characteristics, as the existence of a very advanced embryonic development at oviposition, which is interpreted as an advanced stage in the tendency towards viviparity, and diverse life history characteristics as a very little annual growth which greatly delays sexual maturity to 4 years in males and 4–5 years in females. Clutch size correlates significantly with female snout-vent length (SVL) in all three species. The average clutch size is 2.53 eggs in I. aurelioi (the smallest species), 3.03 in I. bonnali and 3.44 in I. aranica (the biggest species). Notwithstanding the differences in egg number the three species have a similar egg volume. The incubation period in the laboratory is very short with an average of 30–36 days among the species. The low reproductive potential observed in these three species and revealed in this paper is a strongly threatening factor which, together with their extremely reduced distribution area, endangers these endemic, rare and very threatened species.

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