RELATIONSHIP OF CHLOROGENIC ACID CONCENTRATION IN SUNFLOWER ACHENES TO BIRD PREDATION OF SUNFLOWER

1986 ◽  
Vol 66 (1) ◽  
pp. 11-17 ◽  
Author(s):  
D. E. PARFITT ◽  
G. J. FOX ◽  
J. D. BROSZ
Keyword(s):  
Chlorogenic Acid ◽  
Great Plains ◽  
Passer Domesticus ◽  
Northern Great Plains ◽  
Bird Predation ◽  
Xanthocephalus Xanthocephalus ◽  
Helianthus Annus ◽  
Bird Damage ◽  
Relationship Of ◽  
The Relationship

Blackbird feeding on sunflower is a significant problem in parts of the Northern Great Plains. Therefore, experiments were initiated to determine the relationship of chlorogenic acid (CA) in sunflower achenes to bird predation and the amount of variability for CA in sunflower genotypes. Eight inbred sunflower (Helianthus annuus L.) genotypes with variable levels of resistance to blackbird (Agelaius phoeniceus L. and Xanthocephalus xanthocephalus Bonaparte) and house sparrow (Passer domesticus L.) predation were evaluated at two locations in 1979 and 1980 for seed and hull CA. Differences were observed among inbred sunflower genotypes for CA concentration in both hull and seed. However, no significant correlation between percent CA in seed and mean percent bird damage over the four tested environments was observed. An unexpected positive correlation for hull CA and bird damage was found, however. Achene samples were taken from three positions within the sunflower head (outside, middle and inside) from seven inbred lines at three sampling dates. Genotype influenced CA level in both achene components while sampling date influenced CA level in the seed only. Position of achenes within the sunflower head did not influence CA concentration of either hull or seed. Thus, it is unlikely that the CA concentration of physiologically mature sunflower achenes (hull or seed) causes the observed bird predation pattern (edge to center) on sunflower heads. CA concentration is not apparently related to bird damage.Key words: Sunflower, bird feeding, chlorogenic acid, Helianthus annus L., blackbird

Bores Observed during IHOP_2002: The Relationship of Bores to the Nocturnal Environment

2017 ◽  
Vol 145 (10) ◽  
pp. 3929-3946 ◽  
Author(s):  
Kevin R. Haghi ◽  
David B. Parsons ◽  
Alan Shapiro
Keyword(s):  
Great Plains ◽  
Deep Convection ◽  
Horizontal Wind ◽  
Wave Trapping ◽  
Southern Great Plains ◽  
Direction Of Movement ◽  
Low Level Jet ◽  
Relationship Of ◽  
The Relationship ◽  
Scorer Parameter

This study documents atmospheric bores and other convergent boundaries in the southern Great Plains’ nocturnal environment during the IHOP_2002 summer campaign. Observational evidence demonstrates that convective outflows routinely generate bores. Statistically resampled flow regimes, derived from an adaptation of hydraulic theory, agree well with observations. Specifically, convective outflows within the observed environments are likely to produce a partially blocked flow regime, which is a favorable condition for generating a bore. Once a bore develops, the direction of movement generally follows the orientation of the bulk shear vector between the nose of the nocturnal low-level jet and a height of 1.5 or 2.5 km AGL. This relationship is believed to be a consequence of wave trapping through the curvature of the horizontal wind with respect to height. This conclusion comes after analyzing the profile of the Scorer parameter. Overall, these findings provide an impetus for future investigations aimed at understanding and predicting nocturnal deep convection over this region.

Genetic variation in male Yellow-headed Blackbirds from the northern Great Plains

1992 ◽  
Vol 70 (11) ◽  
pp. 2280-2282 ◽  
Author(s):  
Daniel J. Twedt ◽  
William J. Bleier ◽  
George M. Linz
Keyword(s):  
Great Plains ◽  
Geographic Origin ◽  
Northern Great Plains ◽  
North Central ◽  
East Central ◽  
Allelic Frequencies ◽  
Xanthocephalus Xanthocephalus ◽  
Geographic Populations ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Central South

Electrophoretic differences at 15 presumptive loci were used to assess allelic frequencies, heterozygosities, and polymorphism for male Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) collected in east-central Alberta, north-central North Dakota, and east-central South Dakota. Five loci were polymorphic and mean heterozygosities ranged from 0.119 to 0.133. Significant differences were detected among these geographic populations of Yellow-headed Blackbirds, primarily due to differences in the allelic frequencies of isocitrate dehydrogenase and glucose-6-phosphate dehydrogenase. Differences detected were not sufficient to uniquely identify the geographic origin of Yellow-headed Blackbrids.

scholarly journals Relationship between Winter/Spring Snowfall and Summer Precipitation in the Northern Great Plains of North America

2009 ◽  
Vol 10 (5) ◽  
pp. 1203-1217 ◽  
Author(s):  
Steven M. Quiring ◽  
Daria B. Kluver
Keyword(s):  
Great Plains ◽  
Standardized Precipitation Index ◽  
Summer Precipitation ◽  
Northern Great Plains ◽  
Study Region ◽  
Temperature And Precipitation ◽  
Air Temperatures ◽  
Moisture Conditions ◽  
The Relationship ◽  
Preceding Winter

Abstract On the basis of snowfall observations from 1929 to 1999, positive (negative) snowfall anomalies are associated with wetter (drier) than normal conditions during the summer [July–August (JJA)] in the northern Great Plains. The five driest summers are associated with negative snowfall anomalies during the preceding winter (−66.7 mm) and spring (−62.4 mm) that cover most of the study region (∼85%). Snowfall anomalies during the late spring (April–May) are more important for determining summer moisture conditions than snowfall anomalies in fall [September–November (SON)] or winter [December–February (DJF)]. The link between snowfall anomalies and summer moisture conditions appears to be, at least partly, through soil moisture since positive (negative) snowfall anomalies are associated with wetter (drier) soils, a later (earlier) date of snowmelt, cooler (warmer) air temperatures, and more (less) evaporation during spring and summer. However, the relationship between spring snowfall and summer moisture conditions is only statistically significant when the moisture anomaly index (Z), which accounts for both temperature and precipitation, is used to characterize summer moisture conditions and the signal is weak when just considering precipitation (e.g., standardized precipitation index). Results also indicate that the strength of the relationship between winter/spring snowfall and summer moisture varies significantly over space and time, which limits its utility for seasonal forecasting.

The relationship of tissue chlorogenic acid concentrations and leaching of phenolics from sunflowers grown under varying phosphate nutrient conditions

1976 ◽  
Vol 54 (7) ◽  
pp. 593-599 ◽  
Author(s):  
D. E. Koeppe ◽  
L. M. Southwick ◽  
J. E. Bittell
Keyword(s):  
Phenolic Compounds ◽  
Chlorogenic Acid ◽  
Caffeic Acid ◽  
Phosphate Deficiency ◽  
Allelopathic Interactions ◽  
Relationship Of ◽  
The Relationship ◽  
Intact Roots ◽  
Nutrient Conditions

A large increase in the concentration of the isomers of chlorogenic acid was observed in extracts of sunflowers grown under phosphate-deficient conditions when compared with phosphate-sufficient plants. More phenolic compounds were leached from living intact roots, dried roots, and tops of phosphate-deficient plants than from phosphate-sufficient ones. These leachates did not contain any of the isomers of chlorogenic acid or caffeic acid but did contain scopolin. The influence of phosphate deficiency on polyphenol concentrations in plants and their possible role in allelopathic interactions between plants are discussed.

scholarly journals Phylogeographical structure and evolutionary history of two Buggy Creek virus lineages in the western Great Plains of North America

2008 ◽  
Vol 89 (9) ◽  
pp. 2122-2131 ◽  
Author(s):  
Abinash Padhi ◽  
Amy T. Moore ◽  
Mary Bomberger Brown ◽  
Jerome E. Foster ◽  
Martin Pfeffer ◽  
...  
Keyword(s):  
North America ◽  
Great Plains ◽  
Population Decline ◽  
Passer Domesticus ◽  
The Other ◽  
Northern Great Plains ◽  
Coding Region ◽  
Temperate Latitude ◽  
Western Great Plains ◽  
Western Equine Encephalitis

Buggy Creek virus (BCRV) is an unusual arbovirus within the western equine encephalitis complex of alphaviruses. Associated with cimicid swallow bugs (Oeciacus vicarius) as its vector and the cliff swallow (Petrochelidon pyrrhonota) and house sparrow (Passer domesticus) as its amplifying hosts, this virus is found primarily in the western Great Plains of North America at spatially discrete swallow nesting colonies. For 342 isolates collected in Oklahoma, Nebraska, Colorado and North Dakota, from 1974 to 2007, we sequenced a 2076 bp region of the 26S subgenomic RNA structural glycoprotein coding region, and analysed phylogenetic relationships, rates of evolution, demographical histories and temporal genetic structure of the two BCRV lineages found in the Great Plains. The two lineages showed distinct phylogeographical structure: one lineage was found in the southern Great Plains and the other in the northern Great Plains, and both occurred in Nebraska and Colorado. Within each lineage, there was additional latitudinal division into three distinct sublineages. One lineage is showing a long-term population decline. In comparing sequences taken from the same sites 8–30 years apart, in one case one lineage had been replaced by the other, and in the other cases there was little evidence of the same haplotypes persisting over time. The evolutionary rate of BCRV is in the order of 1.6–3.6×10−4 substitutions per site per year, similar to that estimated for other temperate-latitude alphaviruses. The phylogeography and evolution of BCRV could be better understood once we determine the nature of the ecological differences between the lineages.

RELATIONSHIP OF MORPHOLOGICAL PLANT CHARACTERISTICS OF SUNFLOWER TO BIRD FEEDING

1984 ◽  
Vol 64 (1) ◽  
pp. 37-42 ◽  
Author(s):  
DAN E. PARFITT
Keyword(s):  
Passer Domesticus ◽  
Morphological Characters ◽  
Agelaius Phoeniceus ◽  
Feeding Damage ◽  
Head Shape ◽  
House Sparrows ◽  
Breeding Programs ◽  
Helianthus Annus ◽  
Plant Characteristics ◽  
Relationship Of

Bird damage to sunflower (Helianthus annuus L.) is a serious problem in many areas where the crop is grown commercially. This study identifies morphological characters of sunflower that could be used in breeding programs to develop genotypes with improved resistance to bird feeding. An open-pollinated population of sunflower genotypes was tested in four environments for the effects of head shape, bract length, achene size, achene color, plant height, head diameter, distance between head and stem, and head angle. Feeding damage from blackbirds (Agelaius phoeniceus L.) and house sparrows (Passer domesticus L.) was visually estimated. Concave heads, medium distances between the heads and stems, and white achenes discouraged blackbird feeding. Concave heads and downturned heads were aversive to sparrows.Key words: Sunflower, plant characteristics, bird feeding, Helianthus annus L.

Tamarisk (Tamarixspp.) Establishment in its Most Northern Range

2011 ◽  
Vol 4 (1) ◽  
pp. 58-65 ◽  
Author(s):  
Erik A. Lehnhoff ◽  
Fabian D. Menalled ◽  
Lisa J. Rew
Keyword(s):  
Great Plains ◽  
Storage Time ◽  
Storage Period ◽  
Water Levels ◽  
Regulated River ◽  
Northern Great Plains ◽  
Riparian Areas ◽  
Greenhouse Study ◽  
The Relationship ◽  
Hydrologic Conditions

AbstractTamarisk, a shrub or small tree native to Eurasia, was introduced to North America in the early 1800s and is now naturalized throughout many riparian areas of the southwestern United States, where extensive research has been conducted. It is a more recent invader to the northern Great Plains, and fewer studies have been conducted on tamarisk ecology and management in this area. The objectives of this research were to investigate the overwintering potential of tamarisk seeds in Montana and the relationship between hydrologic conditions and historic tamarisk establishment. Emergence of seedlings from seeds stored for different time periods at a range of temperatures was evaluated in a greenhouse study. Emergence rates declined after a 7-d storage period, but storage time had no effect on subsequent emergence rates, and seeds stored at −14 C and 5 C had greater emergence rates than those stored at 20 C and 35 C. Patterns in tamarisk establishment were assessed through age and hydrologic data collected from a reservoir (Fort Peck), a regulated river (Bighorn), and an unregulated river (Yellowstone) in Montana. These data indicated that tamarisk establishment at the reservoir was closely related to historic water levels, whereas establishment on rivers was not related to flow. However, data from the rivers indicated that recruitment differed between regulated and unregulated rivers, with the regulated river having less recruitment after the period of initial colonization than the unregulated river. Our results show that tamarisk seeds have the ability to overwinter in Montana and can establish under a range of flow conditions, indicating potential recolonization of sites after tamarisk removal.

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