PHENOLOGY, REPRODUCTIVE BIOLOGY AND SPATIAL DISTRIBUTION OF Chresta scapigera (LESS.) Gardner (ASTERACEAE)

2021 ◽  
Vol 25 (03) ◽  
pp. 710-721
Author(s):  
Écio Souza Diniz ◽  
◽  
Rodolfo Oliveira Costa ◽  
Larissa Areal Carvalho Müller ◽  
Jan Thiele ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Reproductive Biology ◽  
Floral Biology ◽  
The Self ◽  
Climatic Variables ◽  
Campo Rupestre ◽  
Climatic Data ◽  
Monthly Precipitation ◽  
Leaf Emergence ◽  
Self Pollination

Chrestas capigera (Less.) Gardner is an important medicinal herb which, however, has been poorly studied for its biology and ecology. This study aimed to investigate its phenology, floral biology, reproductive biology (self-pollination tests), spatial distribution and correlations between phenophases and climatic data in two sites (Cerrado stricto sensu and Campo rupestre) in southern Minas Gerais, Brazil. From August of 2012 to August of 2013, we monitored phenophase occurrence for 70 individuals: emission of new leaves, flowering, production of immature fruits, and mature fruits. Floral anthesis occurred during daytime and remained all day until fruit formation. Peak leaf emergence was observed in April, correlating with minimum monthly temperature and mean monthly precipitation. Flowering and green fruit peaked in May and June, respectively, and correlated negatively with all climatic variables. Mature fruits peaked in June, but did not correlate significantly with any of the climatic variables. However, no difference was found between the two sites regarding the timing of phenophases. The spatial distribution pattern of individuals within sites was random. The self-pollination tests showed that the individuals pollinated and fertilized themselves. Our findings allow us to conclude that the phenology of C. scapigera has pronounced phenological seasonality with reproductive peak activities in the drier and colder season, which is congruent with the self-pollination and anemochoric dispersion strategy.

scholarly journals Cytological Observation and Transcriptome Comparative Analysis of Self-Pollination and Cross-Pollination in Dendrobium Officinale

Genes ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 432
Author(s):  
Yaling Chen ◽  
Benchang Hu ◽  
Fantao Zhang ◽  
Xiangdong Luo ◽  
Jiankun Xie
Keyword(s):  
Pollen Tubes ◽  
The Self ◽  
Dendrobium Officinale ◽  
Self Incompatibility ◽  
Related Gene ◽  
Cytological Observation ◽  
Lectin Receptor ◽  
Cross Pollination ◽  
Self Pollination ◽  
Medicinal Value

Dendrobium officinale is a rare and traditional medicinal plant with high pharmacological and nutritional value. The self-incompatibility mechanism of D. officinale reproductive isolation was formed in the long-term evolution process, but intraspecific hybridization of different germplasm resources leads to a large gap in the yield, quality, and medicinal value of D. officinale. To investigate the biological mechanism of self-incompatibility in D. officinale, cytological observation and the transcriptome analysis was carried out on the samples of self-pollination and cross-pollination in D. officinale. Results for self-pollination showed that the pollen tubes could grow in the style at 2 h, but most of pollen tubes stopped growing at 4 h, while a large number of cross-pollinated pollen tubes grew along the placental space to the base of ovary, indicating that the self-incompatibility of D. officinale may be gametophyte self-incompatibility. A total of 63.41 G basesum of D. officinale style samples from non-pollinated, self-pollination, and cross-pollination by RNA-seq were obtained, and a total of 1944, 1758, and 475 differentially expressed genes (DEGs) in the comparison of CK (non-pollinated) vs. HF (cross-pollination sample), CK vs. SF (self-pollination sample) and SF vs. HF were identified, respectively. Forty-one candidate genes related to self-incompatibility were found by function annotation of DEGs, including 6 Ca2+ signal genes, 4 armed repeat containing (ARC) related genes, 11 S-locus receptor kinase (SRK) related genes, 2 Exo70 family genes, 9 ubiquitin related genes, 1 fatty acid related gene, 6 amino acid-related genes, 1 pollen-specific leucine-rich repeat extensin-like protein (LRX) related gene and 1 lectin receptor-like kinases (RLKs) related gene, showed that self-incompatibility mechanism of D. officinale involves the interaction of multiple genes and pathways. The results can provide a basis for the study of the self-incompatibility mechanism of D. officinale, and provide ideas for the preservation and utilization of high-quality resources of D. officinale.

scholarly journals Time Series Analysis of Climatic Variables in Peninsular Spain. Trends and Forecasting Models for Data between 20th and 21st Centuries

Climate ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 119
Author(s):  
Pitshu Mulomba Mukadi ◽  
Concepción González-García
Keyword(s):  
Time Series ◽  
Temperature Series ◽  
Climatic Variables ◽  
Monthly Precipitation ◽  
Agricultural Crops ◽  
Arima Models ◽  
Cover Time ◽  
Pests And Diseases ◽  
Historical Series ◽  
Preliminary Phase

Time series of mean monthly temperature and total monthly precipitation are two of the climatic variables most easily obtained from weather station records. There are many studies analyzing historical series of these variables, particularly in the Spanish territory. In this study, the series of these two variables in 47 stations of the provincial capitals of mainland Spain were analyzed. The series cover time periods from the 1940s to 2013; the studies reviewed in mainland Spain go up to 2008. ARIMA models were used to represent their variation. In the preliminary phase of description and identification of the model, a study to detect possible trends in the series was carried out in an isolated manner. Significant trends were found in 15 of the temperature series, and there were trends in precipitation in only five of them. The results obtained for the trends are discussed with reference to those of other, more detailed studies in the different regions, confirming whether the same trend was maintained over time. With the ARIMA models obtained, 12-month predictions were made by measuring errors with the observed data. More than 50% of the series of both were modeled. Predictions with these models could be useful in different aspects of seasonal job planning, such as wildfires, pests and diseases, and agricultural crops.

Reproductive biology of Melaleuca alternifolia (Myrtaceae) 1. Floral biology

2010 ◽  
Vol 58 (5) ◽  
pp. 373 ◽  
Author(s):  
L. Baskorowati ◽  
M. W. Moncur ◽  
J. C. Doran ◽  
P. J. Kanowski
Keyword(s):  
Reproductive Biology ◽  
Floral Biology ◽  
Morphological Development ◽  
Tea Tree Oil ◽  
Melaleuca Alternifolia ◽  
Tea Tree ◽  
Viable Seeds ◽  
Individual Trees ◽  
Days After Anthesis ◽  
Flowering Intensity

Melaleuca alternifolia (Maiden & Betche) Cheel is commercially important as the source of essential oil for the Australian tea tree-oil industry. Information on reproductive biology of M. alternifolia is important to the Australian breeding program directed at improving the quality and quantity of tea tree oil. Flowering in three geographically separated sites – two planted seed orchards and one managed natural population, all in NSW – was observed in the present study, with supporting data obtained from glasshouse-grown plants in Canberra. The majority of the work was conducted from 2004 to 2007, although the study also drew on some prior observations. M. alternifolia has spikes of flowers that open acropetally over a 6-day period. No strong separation of male and female phases was found in any individual flower; pollen was shed by 1.4 days after anthesis and the stigma reached peak receptivity 3–5 days after anthesis. Dichogamy and acropetal floral development may lead to geitonogamy. Flowering occurred during the months of October–November, with the peak in November, and was synchronous across all three sites. Flowering intensity and success in producing capsules appeared to be associated with total spring rainfall. Initiation of flowering in M. alternifolia appears to be correlated with daylength, or an environmental parameter closely correlated with daylength. Flowering intensity varied considerably among the years surveyed, sites and families, and appears to be promoted by a period of winter minimum temperatures below 5°C. In M. alternifolia, the morphological development of buds, flowers and fruit leading to the development of mature seed takes place over a period 16–18 months from flowering. M. alternifolia differed significantly in the number of viable seeds per capsule from individual trees, from 26 ± 3.8 to 57 ± 3.8 germinants.

scholarly journals Phenology, reproductive biology and growing degree days of the grapevine ‘Isabel’ (Vitis labrusca, Vitaceae) cultivated in northeastern Brazil

2016 ◽  
Vol 76 (4) ◽  
pp. 975-982 ◽  
Author(s):  
N. A. S. Nunes ◽  
A. V. Leite ◽  
C. C. Castro
Keyword(s):  
Reproductive Biology ◽  
Pollen Viability ◽  
Floral Biology ◽  
Climatic Conditions ◽  
Northeastern Brazil ◽  
Growing Degree Days ◽  
Base Temperature ◽  
Vitis Labrusca ◽  
Degree Days ◽  
Inflorescence Development

Abstract Phenology and reproductive biology of cultivated species are important for the comprehension of the requirements for fruit and seed production and the management of pollinators. This study aimed to characterise the phenology, reproductive biology and growing degree days of the grapevine ‘Isabel’ (Vitis labrusca) in northeastern Brazil during January 2011 (P1), Augst 2011 (P2), April 2012 (P3) and August 2012 (P4). We recorded the duration (days) of the phenological stages, pruning (P), woolly bud (W), budburst (B), inflorescence development (ID), flowering (F), ripening (R) and harvest (H). We analysed the floral biology, the sexual system and the breeding system. We measured the growing degree days (GDD) required to reach the subperiods P-B, B-F and F-H. The periods P1, P2, P3 and P4 lasted for 116, 125, 117 and 130 days, respectively. The number of days of harvest were similar in the same dry (P1 and P3) and rainy (P2 and P4) periods. All the periods that we recorded were shorter than those observed in other regions of Brazil, which may be attributable to the mean temperature and carbohydrate metabolism. The flowers are green, hermaphroditic, with an odour of mignonette, low pollen viability and autogamous. The base temperature of 10°C was considered the most adequate for the subperiods as has been documented for other grape varieties in Brazil. Thus, temperature was also the most adequate for the cycles, presenting a smaller standard deviation (0.119, 0.147, 0.156 and 0.153 to P1, P2, P3 and P4, respectively) when compared to a base temperature of 12°C (0.122, 0.158, 0.165 and 0.160 to P1, P2, P3 and P4, respectively). The higher and the lower observed GDD were 1972.17 and 1870.05, respectively, both above the values recorded in other parts of Brazil for same variety. The phonological results, including knowledge of growing degree days, are important to the planning of cultures at the study site and in other regions that have similar climatic conditions and make it possible to pre-determine the harvest.

scholarly journals Dominant Height Model for Site Classification ofEucalyptus grandisIncorporating Climatic Variables

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
José Roberto Soares Scolforo ◽  
Romualdo Maestri ◽  
Antonio Carlos Ferraz Filho ◽  
José Márcio de Mello ◽  
Antônio Donizette de Oliveira ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Eucalyptus Grandis ◽  
Site Index ◽  
Climatic Variables ◽  
Site Classification ◽  
Monthly Precipitation ◽  
Annual Increment ◽  
Dominant Height ◽  
Mean Annual Increment ◽  
Height Model

This study tested the effects of inserting climatic variables inEucalyptus grandisas covariables of a dominant height model, which for site index classification is usually related to age alone. Dominant height values ranging from 1 to 12 years of age located in the Southeast region of Brazil were used, as well as data from 19 automatic meteorological stations from the area. The Chapman-Richards model was chosen to represent dominant height as a function of age. To include the environmental variables a modifier was included in the asymptote of the model. The asymptote was chosen since this parameter is responsible for the maximum value which the dominant height can reach. Of the four environmental variables most responsible for database variation, the two with the highest correlation to the mean annual increment in dominant height (mean monthly precipitation and temperature) were selected to compose the asymptote modifier. Model validation showed a gain in precision of 33% (reduction of the standard error of estimate) when climatic variables were inserted in the model. Possible applications of the method include the estimation of site capacity in regions lacking any planting history, as well as updating forest inventory data based on past climate regimes.

scholarly journals NOAA’s 1981–2010 U.S. Climate Normals: Monthly Precipitation, Snowfall, and Snow Depth

2013 ◽  
Vol 52 (11) ◽  
pp. 2377-2395 ◽  
Author(s):  
Imke Durre ◽  
Michael F. Squires ◽  
Russell S. Vose ◽  
Xungang Yin ◽  
Anthony Arguez ◽  
...  
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Great Plains ◽  
Snow Depth ◽  
State Of The Art ◽  
The United States ◽  
Climatic Data ◽  
Monthly Precipitation ◽  
National Climatic Data Center ◽  
The Caribbean

AbstractThe 1981–2010 “U.S. Climate Normals” released by the National Oceanic and Atmospheric Administration’s (NOAA) National Climatic Data Center include a suite of monthly, seasonal, and annual statistics that are based on precipitation, snowfall, and snow-depth measurements. This paper describes the procedures used to calculate the average totals, frequencies of occurrence, and percentiles that constitute these normals. All parameters were calculated from a single, state-of-the-art dataset of daily observations, taking care to produce normals that were as representative as possible of the full 1981–2010 period, even when the underlying data records were incomplete. In the resulting product, average precipitation totals are available at approximately 9300 stations across the United States and parts of the Caribbean Sea and Pacific Ocean islands. Snowfall and snow-depth statistics are provided for approximately 5300 of those stations, as compared with several hundred stations in the 1971–2000 normals. The 1981–2010 statistics exhibit the familiar climatological patterns across the contiguous United States. When compared with the same calculations for 1971–2000, the later period is characterized by a smaller number of days with snow on the ground and less total annual snowfall across much of the contiguous United States; wetter conditions over much of the Great Plains, Midwest, and northern California; and drier conditions over much of the Southeast and Pacific Northwest. These differences are a reflection of the removal of the 1970s and the addition of the 2000s to the 30-yr-normals period as part of this latest revision of the normals.

scholarly journals Relationship between Climatic Variables and Reproduction Number (R0) of Confirmed COVID-19 Cases

2021 ◽  
Author(s):  
Azad Rasul
Keyword(s):  
Wind Speed ◽  
Reproduction Number ◽  
Virus Transmission ◽  
Climatic Variables ◽  
P Value ◽  
Climatic Data ◽  
High Wind Speed ◽  
Future Studies ◽  
The Relationship ◽  
Socio Economic Factors

Abstract Most transmittable diseases appear in a specific season and the effect of climate on COVID-19 is of special interest. This study aimed to investigate the relationship between climatic variables and R0 of COVID-19 cases in one hundred areas around the world. The daily confirmed cases COVID-19 and climatic data of each area per day from January 2020 to March 2021 are utilized in the study. The GWR and MLR methods were used to identify the relationship between R0 of COVID-19 cases and climatic variables. The MLR results showed a significant (p-value < 0.05) weak inverse relationship between R0 of COVID-19 cases and wind speed, but a positive significant (p-value < 0.01) relationship with precipitation. It implies that lower COVID-19 cases were recorded with high wind speed and low precipitations. Based on GWR, R0 of COVID-19 infection against principal climatic variables has found statistically significant using Monte Carlo p-value test and the effect of climatic variables on COVID-19 infection appears to vary geographically. However, besides climatic variables, many socio-economic factors could influence the virus transmission and will be considered in future studies.

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