Studies in Andean Ocotea (Lauraceae) V. Species with Unisexual Flowers and Sparsely Appressed-Pubescent or Glabrous Leaves without Domatia Occurring above 1000 m in Altitude

2020 ◽  
Vol 28 (3) ◽  
pp. 192-230
Author(s):  
Henk Van der Werff

This is the fifth installment of a treatment of Ocotea Aubl. occurring above 1000-m altitude in the Andean countries of Venezuela, Colombia, Ecuador, Peru, and Bolivia. This part covers species with unisexual flowers lacking distinctive characters such as presence of domatia or erect or dense pubescence on leaves. Twenty-six species are treated, of which 12 are new to science. These are O. nidiae van der Werff from Venezuela; O. erugata van der Werff, O. gymnantha van der Werff, and O. lorda van der Werff from Colombia; O. ceronii van der Werff, O. depilis van der Werff, O. homeieri van der Werff, and O. pilosa van der Werff from Ecuador; and O. calcicola van der Werff, O. fulgida van der Werff, O. nana van der Werff, and O. tunquiensis van der Werff from Peru. Ocotea cernua (Nees) Mez is synonymized with O. leptobotra (Ruiz & Pav.) Mez and O. longifolia Kunth is synonymized with O. aurantiodora (Ruiz & Pav.) Mez.

1985 ◽  
Vol 3 (4) ◽  
pp. 156-157
Author(s):  
Peter B. Schultz

Four Cotoneaster species were evaluated for resistance to hawthorn lace bug. In a preference study using adults, the lace bugs preferred C. x watereri Exell. ‘Brandekeir’ when compared to the other 3 species, C. lacteus W.W.Sm., C. nitens Rehd. & E.H. Wils. and C. acutifolius Turcz. Significantly fewer nymphs completed development on foliage of C. lacteus than on C. x watereri ‘Brandekeir,’ C. nitens and C. acutifolius. The presence of dense pubescence is suggested as a factor in this reduced development.


2021 ◽  
pp. 204361062199583
Author(s):  
Thaís de Carvalho

In Andean countries, the pishtaco is understood as a White-looking man that steals Indigenous people’s organs for money. In contemporary Amazonia, the Shipibo-Konibo people describe the pishtaco as a high-tech murderer, equipped with a sophisticated laser gun that injects electricity inside a victim’s body. This paper looks at this dystopia through Shipibo-Konibo children’s drawings, presenting composite sketches of the pishtaco and maps of the village before and after an attack. Children portrayed White men with syringes and electric guns as weaponry, while discussing whether organ traffickers could also be mestizos nowadays. Meanwhile, the comparison of children’s maps before and after the attack reveals that lit lampposts are paradoxically perceived as a protection at night. The paper examines changing features of pishtacos and the dual capacity of electricity present in children’s drawings. It argues that children know about shifting racial dynamics in the village’s history and recognise development’s oxymoron: the same electricity that can be a weapon is also used as a shield.


2000 ◽  
Vol 77 (11) ◽  
pp. 1569-1579
Author(s):  
W A Charlton

Wiesneria triandra (Dalzell) Micheli is an unusual annual plant of the Alismataceae with spike-like inflorescences bearing unisexual flowers. Shoot development follows the sympodial pattern of other Alismataceae, but the cycle is so condensed that initiation of each foliage leaf is followed by inflorescence formation. The plant develops a tufted habit by the formation of an unusual accesory bud adjacent to each inflorescence. Male flowers have three sepals, three petals, three stamens, and usually three carpellodes; female flowers have a similar perianth, three staminodes, and three or more carpels. Up to the first three carpels, floral parts are arranged in alternating trimerous whorls. Additional carpels may occur above and between those of the first whorl. The androecium is particularly unusual for the Alismataceae since it has conventional alternation of stamens with petals rather than the antipetalous pairs of stamens commonly perceived in the family, but the phylogenetic postion of Wiesneria within the family (as revealed by other studies) indicates that the apparently conventional androecium of Wiesneria represents a derived state rather than a primitive one. The unisexual flowers also represent a derived state.


2007 ◽  
Vol 23 (5) ◽  
pp. 607-610 ◽  
Author(s):  
Mathieu Chouteau ◽  
Melanie McClure ◽  
Marc Gibernau

Data on pollination ecology of Araceae are still scarce and most concern species belonging to the subfamily Aroideae (García-Robledo et al. 2004, Gibernau 2003, Ivancic et al. 2004, 2005; Maia & Schlindwein 2006). In this subfamily, inflorescences consist of unisexual flowers: female flowers are located in the lower portion and the male flowers are in the upper portion of the inflorescence (Mayo et al. 1997). In the documented neotropical Aroideae, pollinators are nocturnal beetles and pollination mechanisms take place within a floral chamber during a short flowering cycle (generally 24–48 h) with floral rewards (sterile flowers rich in proteins and/or lipids) for the beetle pollinators, the secretion of resin to secure pollen on the pollinator, and the production of heat and odours (Chouteau et al. 2007, García-Robledo et al. 2004, Gibernau & Barabé 2002, Gibernau et al. 1999, 2000, 2003; Maia & Schlindwein 2006, Young 1986).


2021 ◽  
Author(s):  
Mateus C. R. Neves ◽  
Felipe De Figueiredo Silva ◽  
Carlos Otávio Freitas

In this working paper, we estimate agricultural total factor productivity (Ag TFP) for South American countries over the period 19692016 and identify how road density affect technical efficiency. In 2015, Colombia, Peru, Venezuela, Ecuador, and Bolivia, the Andean countries, had 205,000; 166,000; 96,000; 89,000; and 43,000 kilometers of roads, respectively. A poor-quality and limited road network, along with inaccessibility to markets, might limit the ability of farms to efficiently manage production inputs, raising technical inefficiency. We find that the Ag TFP growth rate per year for South American countries, on average, is 1.5%. For the Andean countries, we find an even smaller growth rate per year of 1.4% on average. Our findings suggest that higher road density is associated with lower technical inefficiency.


2021 ◽  
Author(s):  
Mateus C. R. Neves ◽  
Felipe De Figueiredo Silva ◽  
Carlos Otávio Freitas

In this paper we estimate the average treatment effect from access to extension services and credit on agricultural production in selected Andean countries (Bolivia, Peru, and Colombia). More specifically, we want to identify the effect of accessibility, here represented as travel time to the nearest area with 1,500 or more inhabitants per square kilometer or at least 50,000 inhabitants, on the likelihood of accessing extension and credit. To estimate the treatment effect and identify the effect of accessibility on these variables, we use data from the Colombian and Bolivian Agricultural Censuses of 2013 and 2014, respectively; a national agricultural survey from 2017 for Peru; and geographic information on travel time. We find that the average treatment effect for extension is higher compared to that of credit for farms in Bolivia and Peru, and lower for Colombia. The average treatment effects of extension and credit for Peruvian farms are $2,387.45 and $3,583.42 respectively. The average treatment effect for extension and credit are $941.92 and $668.69, respectively, while in Colombia are $1,365.98 and $1,192.51, respectively. We also find that accessibility and the likelihood of accessing these services are nonlinearly related. Results indicate that higher likelihood is associated with lower travel time, especially in the analysis of credit.


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