scholarly journals Seasonal change of flower sex ratio and pollinator dynamics in three reproductive ecotypes of protandrous plant

Ecosphere ◽  
2020 ◽  
Vol 11 (9) ◽  
Author(s):  
Tsubasa Toji ◽  
Natsumi Ishimoto ◽  
Takao Itino
Keyword(s):  
Sex Ratio ◽  
Seasonal Change ◽  
Flower Sex Ratio

scholarly journals Assessment of weather effect on flower morphogenesis and fruit set in mango varieties in central India

2022 ◽  
Vol 24 (1) ◽  
Author(s):  
N. R. RANGARE ◽  
MANISH BHAN ◽  
S. K. PANDEY
Keyword(s):  
Sex Ratio ◽  
Minimum Temperature ◽  
Fruit Set ◽  
Male Flower ◽  
Central India ◽  
Flower Initiation ◽  
Hermaphrodite Flower ◽  
Flower Morphogenesis ◽  
Bud Initiation ◽  
Flower Sex Ratio

A two-year field experiment was initiated in 2017-18 and 2018-19 years simultaneously to assess temperature on flower morphogenesis stages, flower sex ratio (hermaphrodite/staminate male flower) and fruit set in monoembryonic Langra and Amrapali varieties. Different dates of flower phenological stages viz., bud, panicle, bloom and flower initiation, pea, marble, egg, and maturity of fruits were recorded. The Langra variety exhibited bud initiation after mid December whereas Amrapali variety by the end of December. The range of mean maximum / minimum temperature as 26-31/10-12 °C promoted hermaphrodite flowers per panicle by 74 per cent in Langra variety, whereas range of 27-29/11-13 °C favored by 35 per cent in Amrapali variety. A positive and significant correlation between total number of flower / panicle and flower sex ratio in both the varieties suggested that higher temperature during initial flower phenologies improved number of hermaphrodite flowers. A mean minimum temperature for producing more number of hermaphrodite flower  exhibited a range of 11-14 °C under central Indian conditions.  Fruit set was maximum during pea stage and decline afterwards in marble and fruit maturity stages due to sudden rise in temperature at marble stage that caused in drop down of humidity thereby resulted in fruit drop in both the varieties.

Seasonal change in sex ratio in Acraea quirina (F.) (Lep. Nymphalidae), and notes on the factors causing distortions of the sex ratio in butterflies

1974 ◽  
Vol 5 (2) ◽  
pp. 110-114 ◽  
Author(s):  
D.F. Owen
Keyword(s):  
Sex Ratio ◽  
Sierra Leone ◽  
Seasonal Change ◽  
Sex Ratios ◽  
Wet Season ◽  
Two Generations

AbstractThe butterfly, Acraea quirina, occurs as an adult in all months of the year in forests around Freetown in Sierra Leone. For ninc months (July— March) it is not common but in April—June, at the onset of the wet season, becomes exceedingly abundant. During this period there are two generations, the first containing mainly females, while in the second there is what is probably a normal sex ratio. In butterflies the sex ratio is usually 1 : 1 but a number of instances of an excess of females are now known. The possible mechanisms and significance of distorted sex ratios in butterflies are discussed, not only for A. quirina, but for other species, including Hypolimnas bolina.

scholarly journals Status, abundance and population ecology of Nilgai (Boselaphus tragocamelus Pallas) in Aligarh District, Uttar Pradesh, India

2016 ◽  
Vol 8 (2) ◽  
pp. 1080-1086 ◽  
Author(s):  
Khursid A. Khan ◽  
Jamal A. Khan
Keyword(s):  
Sex Ratio ◽  
Seasonal Change ◽  
Group Size ◽  
Population Ecology ◽  
Group Structure ◽  
Uttar Pradesh ◽  
Summer Season ◽  
Encounter Rate ◽  
Female Ratio

The data on population ecology of nilgai was collected in Aligarh District, Uttar Pradesh, India from August 2013 to June 2014. A total of 108 herds of nilgai 54 in each season (summer and winter) were encountered, respectively. The density of nilgai was found 0.49/km2 in Aligarh district. While the encounter rate was found 0.66individuals per km. There was a mark seasonal change seen in group size of nilgai i.e. 11.38 ± 2.76, and 22.83 ± 5.40 in winter and summer, respectively. The overall mean group size was found 17.10 ± 4.08. The sex ratio of nilgai was female biased, adult male:adult female ratio was found 1:3 while overall sex ratio was found 61.55%,26.32% and 44% male, yearling and calves on per 100 females, respectively. The nilgai shows mark seasonal change in their group structure. The group size was found maximum at 25% in 0-5 individual category and minimum 9.25 in >21 category in winter, while about 30% were seen in >21 category and only 11% were seen in between 0-5 category in summer season. Thus, the nilgai was found less sociable in winter and more gregarious in summer season.

Effect of flower sex ratio on fruit set in pumpkin (Cucurbita maxima)

2019 ◽  
Vol 246 ◽  
pp. 1005-1008 ◽  
Author(s):  
Sinu Palatty Allesh ◽  
Sangeetha Varma ◽  
K.S. Reshmi ◽  
K. Aswathi ◽  
P.P. Megha ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Fruit Set ◽  
Cucurbita Maxima ◽  
Flower Sex Ratio

Die unbehandelten Kranken: Ältere Männer mit Depression

2008 ◽  
Vol 27 (07) ◽  
pp. 617-619 ◽  
Author(s):  
M. Wittmann ◽  
E. Haen ◽  
H. Spießl ◽  
H. Hausner
Keyword(s):  
Sex Ratio ◽  
Epidemiologische Studien

ZusammenfassungZahlreiche epidemiologische Studien zeigen, dass sich das Geschlechterverhältnis der Prävalenz depressiver Erkrankungen ab der 6. Lebensdekade – also nach der weiblichen Menopause – wieder annähert. Wir haben untersucht, ob sich dieser epidemiologische Effekt auch in der stationären Versorgung abbildet. Unter Verwendung der AGATE-Stichtagsdaten der Jahre 2000 bis 2004, wurde der Zusammenhang zwischen Geschlecht und Alter bei stationär behandelten depressiven Patienten analysiert. Der Zusammenhang zwischen Geschlechterverhältnis und dem Alter wurde mithilfe des Korrelationskoeffizienten nach Spearman sowie mit χ2-Test untersucht. In der 5. und 6. Lebensdekade lag die Sex-Ratio F/M bei 1,7:1, sie stieg in der 7. Dekade auf 2,2:1 und in der 8. Dekade auf 2,6:1 an. Anders als aufgrund epidemiologischer Studien zu erwarten wäre, nähert sich in der stationär psychiatrischen Versorgung das Verhältnis depressiver Patienten im Alter nicht an. Depressive ältere Männer sind also im stationären Versorgungssystem unterrepräsentiert.

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