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Context: Cultivation of quinoa (Chenopodium quinoa Willd.) is rapidly expanding worldwide. Characterisation of populations of Chenopodium hircinum Schard., its wild ancestor, which thrives in some of the hottest environments in South America, may provide adaptations to new environments. Aims: This study evaluated the developmental patterns of populations of C. hircinum collected from a range of agroecological environments in Argentina, in order to quantify variability among sites of origin and to explore the association between climatic data from environments of provenance and variation in development. Methods: Thirty-three populations of C. hircinum from contrasting sites of origin in Argentina were multiplied in a common-garden experiment under non-limiting conditions of water and nutrient availability. Plants were sampled once or twice weekly (according to parameter) for estimation of the duration of developmental phases, leaf number, and dates of initiation of branching on the main stem. Key results: Significant variation was detected for all phenological traits, and populations were categorised into six groups based on similarity of patterns of variation. We found positive association of the duration of development phases and the number of leaves on the main-stem with maximum temperature during the growing season, and negative association with altitude of origin, consistent with variation in growing-season duration. Conclusions: The finding that late-flowering populations are associated with warmest climates reveals that longer vegetative growth is an adaptive strategy to cope with heat stress in Chenopodium spp. Implications: Time to flowering should be considered in attempts to improve quinoa performance under heat-stress conditions. Further work is needed to understand the genetic basis controlling this response in wild populations of C. hircinum. Chenopodium hircinum , the wild ancestor of quinoa, thrives in some of the hottest environments in South America. We found a wide range of variability for phenological traits among Argentinean populations of C. hircinum related to climatic variables from their sites of provenance. Populations originating from warmer climates show a suitable set of phenological traits for development of future quinoa varieties with resistance to heat stress. [ABSTRACT FROM AUTHOR]

Cactus flowers have traditionally been considered to be specialized to certain pollination guilds, but pollination studies reveal that most species are actually generalists. This suggests that floral traits are not always predictive of the animal visitors that pollinate cactus flowers. Here, we studied the pollination of Echinopsis leucantha (Gillies ex Salm-Dyck) Walp., an endemic cactus of Argentina, whose floral traits would suggest that it is pollinated by moths. The floral lifespan and flower availability throughout the reproductive period were evaluated. Field experiments were carried out to study the reproductive system and the identity and effectiveness of floral visitors. Echinopsis leucantha flowers had a nocturnal anthesis time that extended into the following morning. The species was self-incompatible. Floral visitors included moths, bees, and passerine birds. However, diurnal visitors were more effective as pollinators than nocturnal ones. The flowers of E. leucantha were phenotypically specialized (sphingophily); however, the pollination system was functionally and ecologically generalized. The results confirm that generalized pollination systems are widespread among species of the Echinopsis genus with nocturnal flowers, for which diurnal pollinators seem to have a key role in fruit and seed production. Our study constitutes the first record of passerine bird pollination in the Cactaceae for mainland South America. Keywords: Cactaceae, Echinopsis, floral syndrome, passerine, pollination. Les fleurs de cactus ont traditionnellement ete considerees comme specialisees envers certaines guildes de pollinisateurs, mais les etudes de pollinisation revelent que la plupart des especes sont en fait generalistes. Cela suggere que les traits floraux ne sont pas toujours predicteurs des visiteurs animaux qui pollinisent les fleurs de cactus. Les auteurs ont etudie ici la pollinisation d'Echinopsis leucantha (Gillies ex Salm-Dyck) Walp., un cactus endemique de l'Argentine, dont les traits floraux pourraient suggerer qu'il est pollinise par des papillons nocturnes. La duree de vie et la disponibilite des fleurs a travers toute la periode de reproduction ont ete evaluees. Des experiences sur le terrain ont ete realisees afin d'etudier le systeme reproducteur et l'identite et l'efficacite des visiteurs floraux. Les fleurs d'E. leucantha avaient une periode d'anthese nocturne qui s'etendait durant la matinee suivante. L'espece etait auto-incompatible. Les visiteurs floraux comprenaient les papillons nocturnes, les abeilles et les passereaux. Cependant, les visiteurs diurnes etaient des pollinisateurs plus efficaces que les visiteurs nocturnes. Les fleurs d'E. leucantha etaient specialisees phenotypiquement (sphingophilie); cependant, le systeme pollinisateur etait fonctionnellement et ecologiquement generaliste. Les resultats confirment que les systemes de pollinisation generalistes sont repandus chez les especes du genre Echinopsis possedant des fleurs nocturnes, pour lesquelles les pollinisateurs diurnes semblent jouer un role cle dans la production de fruits et de graines. Leur etude est la premiere a rapporter une pollinisation par des passereaux chez des Cactaceae du continent sudamericain. [Traduit par la Redaction] Mots-cles : Cactaceae, Echinopsis, syndrome floral, passereau, pollinisation., Introduction Most angiosperms have been found to have generalist pollination systems, and specialization is now believed to be less common than once supposed (Waser et al. 1996; Ollerton et al. [...]

As a contribution to understanding the world biogeography of seed dormancy in the cosmopolitan genus Ilex, we studied seeds of I. argentina, I. brasiliensis, I. brevicuspis, I. dumosa, I. paraguariensis and I. theezans from the subtropical region of Argentina. We hypothesized that seeds of these species have non-deep simple morphophysiological dormancy (MPD). Effects of temperature, cold stratification and gibberellic acid (GA3) on seed germination and embryo growth were tested. Regardless of incubation temperature, little or no germination occurred for any species until ≥6 weeks. There was an up to 3-fold increase in embryo length to seed length (E:S) ratio before seeds germinated, and embryos grew only during warm-stratifying conditions. Seeds of I. brasiliensis, I. brevicuspis and I. theezans had non-deep simple MPD and germinated to ≥80% after 12, 24 and 16 weeks, respectively. Cold stratification increased germination of I. brasiliensis and I. brevicuspis, and GA3 increased the rate but not final germination percentage of I. brasiliensis and I. theezans. Fresh seeds of I. dumosa required 40 weeks of warm stratification to germinate to 53%, while those after-ripened for 2 months germinated to 81% after 30 weeks; this species has intermediate simple MPD. Seeds of I. argentina and I. paraguariensis germinated to 15 and 21%, respectively, after 40 weeks of warm stratification and did not after-ripen or respond to GA3; these seeds have deep simple MPD. This is the first report of intermediate and deep simple MPD that is broken by warm stratification, thereby increasing our knowledge of seed dormancy in Ilex and in subtropical regions. [ABSTRACT FROM AUTHOR]

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The Cactaceae family in Argentina: diversity patterns and political priorities for their conservation. In this paper we used species richness and endemism of Argentine cacti to select those provinces with highest priority for the conservation of this plant family in the country. The role of cactus diversity as a surrogate for dicot diversity was further analyzed. Species richness (number of species) and endemism (number of endemic species) were determined for each of the 24 provinces of Argentina. Fifteen provinces were selected as priority based on the number of species and 14 provinces were selected based on the number of endemic species. Salta province presents the highest species richness and endemism. Endemic species are a good surrogate for cactus diversity. Similarly, cactus diversity is a good surrogate for dicot diversity. [ABSTRACT FROM AUTHOR]

Copyright of Botanical Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)