scholarly journals Producción de estructuras reproductivas y fenología reproductuva de cinco especies de compuestas en una comunidad xerófita

2017 ◽  
pp. 67
Author(s):  
Dulce María Figueroa-Castro ◽  
Zenón Cano-Santana ◽  
Edgar Camacho-Castillo
Keyword(s):  
Rainy Season ◽  
Reproductive Period ◽  
Dry Season ◽  
Reproductive Phenology ◽  
Central Mexico ◽  
Light Conditions ◽  
Mature Fruit ◽  
Reproductive Structures ◽  
Open Site ◽  
Fruit Stage

We studied the production of reproductive structures and the reproductive phenology of five Compositae species in a xeric community in Central Mexico: Eupatorium petiolare, Tagetes lunulata, Senecio praecox, Dahlia coccinea and Verbesina virgata. The last three species were studied in two sites with contrasting light conditions. The number of reproductive structures produced by D. coccinea was higher in the open site than in the shaded one. In contrast, S.praecox had a higher production in the shaded site, but V. virgata showed no differences. The reproductive phenology of V. virgata and D. coccinea was different between sites, but it was not happen in S. praecox. The species that flowered during the dry season had a shorter reproductive period (E. petiolare: 2.8 mo; S. praecox: 2.0 mo) than those that flowered during the rainy season or during the late rainy season (D. coccinea: 11.0 mo; T. lunulala: 8.5 mo; V. virgata: 8.5 mo) , which was caused by the high duration of the mature fruit stage in these species.

scholarly journals Intra annual seed production and availability of two morphotypes of Brosimum rubescens taubert in forests of the Colombian Amazon

2014 ◽  
Vol 14 (4) ◽  
Author(s):  
Luis Eduardo Rivera ◽  
María Cristina Peãuela ◽  
Flavio Moreno
Keyword(s):  
Seed Production ◽  
Annual Cycle ◽  
Rainy Season ◽  
Dry Season ◽  
Primary Forest ◽  
Reproductive Phenology ◽  
Seed Limitation ◽  
Biological Station ◽  
Reproductive Structures ◽  
Colombian Amazon

We assessed the reproductive phenology, production, and availability of seeds for two morphotypes of Brosimum rubescens Taub. (Moraceae), locally known as black palosangre (BP) and white palosangre (WP) during an annual cycle in a 20-ha mega plot located in a primary forest at the El Zafire Biological Station, in the Colombian Amazon. We found that 87% and 41% of potentially reproductive individuals of BP and WP respectively, was fertile and the production of reproductive structures was variable within and between morphotypes. The phenological pattern was seasonal in both morphotypes, characterized by flowering at the end of the dry season and fruiting at the start of the rainy season. BP produced and aborted large amounts of infructescences (approximately 21743), possibly as a response to satiate predators. Relative predation in terms of pre-dispersion of seeds was similar in both morphotypes, with a greater damage generated by a Scolytidae Curculionidae (Coleoptera) and to a lesser degree by frugivorous vertebrates. The number of mature fruits, total seeds, and removed seeds was similar for both morphotypes. Differences in the amount of reproductive structures and in the timing of phenophases between morphotypes decreased the competition and contributed to their coexistence. It seems that in undisturbed forests seed limitation could be more conditioning for WP, while other limitations after fruit and seed production could occur in BP.

scholarly journals Phenological observations and sex ratios in Marchantia chenopoda L. (Hepaticae: Marchantiaceae)

1992 ◽  
Vol 6 (1) ◽  
pp. 161-168 ◽  
Author(s):  
María T. Moyá
Keyword(s):  
Puerto Rico ◽  
Rainy Season ◽  
Sex Ratios ◽  
Dry Season ◽  
Reproductive Structures ◽  
Female Bias ◽  
Young Sporophytes

Sex ratios were determined for 15 populations of Marchantia chenopoda L. along Puerto Rico. Sex was determined for twenty randomly selected individuals from each population. A female bias was observed in most populations. A census of reproductive structures of M. chenopoda was performed every two weeks in order to determine phenology. The highest archegoniophore count was observed to occur in January and February; minimum and maximum fertilization distances were 0.7 cm and 65 cm, respectively. Young sporophytes were most frequently observed at the beginning of the rainy season, in April and May. The highest frequency of mature sporophytes occurred during the dry season, in January and February. Capsules opened mostly during the heavy rainy season, from August to November. Protonemata were observed in the periphery of the population. Most young sporophytes aborted at the end of the moderate to heavy rainy season, from June to August. Immature gemmae cups were most frequent at the beginning of the rainy season, in April and May. Mature gemmae cups were observed throughout the rainy season, but were most frequent in September.

Croton blanchetianus modulates its morphophysiological responses to tolerate drought in a tropical dry forest

2017 ◽  
Vol 44 (10) ◽  
pp. 1039 ◽  
Author(s):  
Keila R. Mendes ◽  
João A. A. Granja ◽  
Jean P. Ometto ◽  
Antônio C. D. Antonino ◽  
Rômulo S. C. Menezes ◽  
...  
Keyword(s):  
Rainy Season ◽  
Tropical Dry Forest ◽  
Net Photosynthesis ◽  
Leaf Traits ◽  
Co2 Assimilation ◽  
Dry Season ◽  
Dry Forest ◽  
Light Conditions ◽  
Dry Tropical Forests ◽  
Use Efficiency

An understanding of variations in morphophysiological leaf traits of plant models in dry tropical forests is essential for quantifying C fluxes from forest ecosystems in response to climate changes. The present study evaluated the influences of seasonal rainfall and different light conditions on the gas exchange, nutrients, organic compounds and morphological traits in Croton blanchetianus Baill. trees within a fragment of Caatinga forest. Stomatal conductance (gs) and net photosynthesis (PN) demonstrated variations within the diurnal cycle, with maximum values at approximately midday and minimum values at predawn. The PN and the diurnal integrated CO2 assimilation were lower during the dry season than in the rainy season. Water use efficiency was positively correlated with PN (r = 0.73) during the dry season only. However, the correlation between PN and gs was observed during the rainy season only (r = 0.60). Thus we demonstrated that C. blanchetianus has a remarkable ability to adapt to global climatic changes and could be considered a model in studies exploring water relationships in woody plants; consequently, this species may be important in future reforestation studies.

scholarly journals Mold species and fungi load of washed and unwashed table eggs

2020 ◽  
Vol 14 (4) ◽  
pp. 286-290
Author(s):  
Naiara Silva Menezes Dantas ◽  
Luciene Almeida Siqueira de Vasconcelos ◽  
Pedro de Queiroz Costa Neto ◽  
Felipe Faccini dos Santos
Keyword(s):  
Rainy Season ◽  
Egg Quality ◽  
Tween 80 ◽  
Dry Season ◽  
Potato Dextrose Agar ◽  
Exploratory Research ◽  
Microscopy Observation ◽  
Reproductive Structures ◽  
Large Size ◽  
Egg Shells

Egg quality has been widely studied, mainly because defects in quality can pose risks to public health, as well as economic losses.Nevertheless, studies about fungiin eggsare scarce. The objective was to compare the fungal microbiota from washed and unwashed eggs in the rainy season and dry season of the year. This exploratory research consisted in the analysis of large size white table eggs acquired from 48 different lots. Two manufacturers were sampled considering the main characteristic of washed or unwashed eggs. From each lot, a 30-egg pack were purchased and six of those eggs were used for mycological analyzes. The eggs were analyzed externally with 0.1% peptone salt solution wash of the eggshells and internally with aliquots being sampled from a pool made from the six eggs content. Samples were inoculated in Potato Dextrose Agar and isolated colonies were passed to test tubes. When sporulated, the isolates were subjected to decimal dilutions using 0.1% Tween 80 to dissociate the conidia. Microcultures were carried out for optical microscopy observation of the reproductive structures of fungi, stained with lactophenol. Aspergillusspp. was the most frequently isolated fungi isolated, with A. nigerand A. flavuspredominant in the dry season, while A. fumigatusand A. terreusin the rainy season. Low numbers of fungi were identified from egg shells, with a higher amount from unwashed eggs. The seasondid not influence the numberof fungi in eggs, despite having influenced the fungal diversity.

scholarly journals Floristics and Reproductive Phenology of Trees and Bushes in Central West Brazil

2014 ◽  
Vol 86 (2) ◽  
pp. 785-800 ◽  
Author(s):  
VIVIAN A. ASSUNÇÃO ◽  
JOSÉ C. CASAGRANDE ◽  
ÂNGELA L.B. SARTORI
Keyword(s):  
Principal Component Analysis ◽  
Environmental Conditions ◽  
Physical Environment ◽  
Rainy Season ◽  
Deciduous Forest ◽  
Principal Component ◽  
Reproductive Period ◽  
Reproductive Phenology ◽  
Similarity Analysis ◽  
Floristic Similarity

Environmental conditions such as temperature, soil, photoperiodic factors and precipitation can determine the physical environment favoring the occurrence of given species and interfere with the reproductive period of plants. This work involved monthly excursions to a slope in the Serra de Maracaju between December 2009 and November 2010. Samples were collected in eight 25 x 50 m plots, transverse to the slope, totaling 1 ha sampled. Floristic richness included 79 species distributed into 58 genera and 31 families. Floristic Similarity Analysis and Principal Component Analysis showed the occurrence of two plant formations on the slope: seasonal deciduous forest andcerradão on the eutrophic soil of the slope. Flowering and fruiting occured in the rainy season; correlation with rainfall, mean temperature and photoperiod were negative for flowering and positive for fructification. Trees and bushes presented uniform flowering and a moderately seasonal fructification, which is unexpected in seasonal environments. We discuss the implications of the patterns found and make comparisons with others studies.

scholarly journals Diversity of Planthoppers (Hemiptera: Delphacidae) on Maize Crops and Edge Grasses in Mexico

2020 ◽  
Vol 49 (5) ◽  
pp. 1088-1095
Author(s):  
José Guillermo Rodríguez-Juárez ◽  
Charles R Bartlett ◽  
J Adilson Pinedo-Escatel ◽  
Gustavo Moya-Raygoza
Keyword(s):  
Plant Pathogen ◽  
Rainy Season ◽  
Plant Pathogens ◽  
Abundant Species ◽  
Dry Season ◽  
Central Mexico ◽  
Sap Feeding ◽  
High Diversity ◽  
Sweep Net ◽  
Dry And Rainy Seasons

Abstract Delphacid planthoppers (Hemiptera: Delphacidae) are a group of economically important sap-feeding insects that vector plant pathogens and are pests of crops, such as maize, wheat, and rice. This study was conducted to evaluate planthopper diversity, abundance, and the presence of potential vectors on maize crops and associated edge grass habitats. In Jalisco, west-central Mexico, delphacids were sampled using a sweep net in two different habitats (with and without irrigation) during the dry and rainy seasons of 2013 and 2014. A total of 5,621 specimens were collected and nine species were identified: Metadelphax propinqua (Fieber), Delphacodes koebelei Muir and Giffard, Delphacodes arcuata Beamer, Sogatella kolophon (Kirkaldy), Syndelphax fulvidorsum (Metcalf), Chionomus balboae (Muir & Giffard), Toya idonea (Beamer), Syndelphax humilis (Van Duzee), and Tagosodes cubanus (Crawford) (Hemiptera: Delphacidae), all belonging to the tribe Delphacini (Delphacinae). A high diversity of delphacids was found in the edge grasses during the dry season and rainy season. Planthopper abundance was higher in the edge grasses than in the maize fields during the rainy season. The most abundant species was M. propinqua representing 67.5% of the specimens collected. Populations of M. propinqua in edge grasses peaked during the dry season in December and January. Metadelphax propinqua, S. kolophon, and T. cubanus are known to be potential plant pathogen vectors.

STUDI BIONOMIK VEKTOR MALARIA DI KECAMATAN KALIBAWANG, KULONPROGO

2018 ◽  
Vol 4 (2) ◽  
Author(s):  
Sardjito Eko Windarso dkk
Keyword(s):  
Land Use ◽  
Malaria Vector ◽  
Rainy Season ◽  
Dry Season ◽  
Physical Factors ◽  
Mosquito Vector ◽  
Anopheles Species ◽  
Commercial Farming ◽  
Study Results ◽  
Dry And Rainy Seasons

The increasing of malaria cases in recent years at Kecamatan Kalibawang has been suspected correspond with the conversion of farming land-use which initiated in 1993. Four years after the natural vegetation in this area were changed become cocoa and coffee commercial farming estates, the number of malaria cases in 1997 rose more than six times, and in 2000 it reached 6085. This study were aimed to observe whether there were any differences in density and diversity of Anopheles as malaria vector between the cocoa and mix farming during dry and rainy seasons. The results of the study are useful for considering the appropriate methods, times and places for mosquito vector controlling. The study activities comprised of collecting Anopheles as well as identifying the species to determine the density and diversity of the malaria vector. Both activities were held four weeks in dry season and four weeks in rainy season. The mea-surement of physical factors such as temperature, humidity and rainfall were also conducted to support the study results. Four dusuns which meet the criteria and had the highest malaria cases were selected as study location. Descriptively, the results shows that the number of collected Anopheles in cocoa farming were higher compared with those in mix horticultural farming; and the number of Anopheles species identifi ed in cocoa farming were also more varied than those in the mix horticultural farming.Key words: bionomik vektor malaria, anopheles,

scholarly journals Understanding variability in greenhouse gas emission estimates of smallholder dairy farms in Indonesia

2021 ◽  
Author(s):  
Titis Apdini ◽  
Windi Al Zahra ◽  
Simon J. Oosting ◽  
Imke J. M. de Boer ◽  
Marion de Vries ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Rainy Season ◽  
Greenhouse Gas Emission ◽  
Dairy Farms ◽  
Dry Season ◽  
Enteric Fermentation ◽  
Tropical Regions ◽  
Population Mean ◽  
Smallholder Dairy ◽  
Smallholder Dairy Farms

Abstract Purpose Life cycle assessment studies on smallholder farms in tropical regions generally use data that is collected at one moment in time, which could hamper assessment of the exact situation. We assessed seasonal differences in greenhouse gas emissions (GHGEs) from Indonesian dairy farms by means of longitudinal observations and evaluated the implications of number of farm visits on the variance of the estimated GHGE per kg milk (GHGEI) for a single farm, and the population mean. Methods An LCA study was done on 32 smallholder dairy farms in the Lembang district area, West Java, Indonesia. Farm visits (FVs) were performed every 2 months throughout 1 year: FV1–FV3 (rainy season) and FV4–FV6 (dry season). GHGEs were assessed for all processes up to the farm-gate, including upstream processes (production and transportation of feed, fertiliser, fuel and electricity) and on-farm processes (keeping animals, manure management and forage cultivation). We compared means of GHGE per unit of fat-and-protein-corrected milk (FPCM) produced in the rainy and the dry season. We evaluated the implication of number of farm visits on the variance of the estimated GHGEI, and on the variance of GHGE from different processes. Results and discussion GHGEI was higher in the rainy (1.32 kg CO2-eq kg−1 FPCM) than in the dry (0.91 kg CO2-eq kg−1 FPCM) season (P < 0.05). The between farm variance was 0.025 kg CO2-eq kg−1 FPCM in both seasons. The within farm variance in the estimate for the single farm mean decreased from 0.69 (1 visit) to 0.027 (26 visits) kg CO2-eq kg−1 FPCM (rainy season), and from 0.32 to 0.012 kg CO2-eq kg−1 FPCM (dry season). The within farm variance in the estimate for the population mean was 0.02 (rainy) and 0.01 (dry) kg CO2-eq kg−1 FPCM (1 visit), and decreased with an increase in farm visits. Forage cultivation was the main source of between farm variance, enteric fermentation the main source of within farm variance. Conclusions The estimated GHGEI was significantly higher in the rainy than in the dry season. The main contribution to variability in GHGEI is due to variation between observations from visits to the same farm. This source of variability can be reduced by increasing the number of visits per farm. Estimates for variation within and between farms enable a more informed decision about the data collection procedure.

Sign in / Sign up

Export Citation Format

Share Document