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One of the major constraints to profitable soybean [Glycine max (L.) Merr.] production is yield losses caused by disease. The mid-southern region of the United States typically experiences environmental conditions that are conducive to disease development, particularly during later reproductive growth stages. It is common for producers in this region to apply fungicides at the beginning of pod development (R3 growth stage; development of pods 3/16 inches long). Producers often question if establishing crops in different row patterns would alter the yield response to prophylactic fungicide applications. Producers also seek answers regarding the yield and grain quality responses to fungicide applications across different row patterns. However, limited data exist to determine if fungicide applications influence the responses of soybean’s yield and grain quality between different row spacings. The objective of this research was to evaluate soybean’s growth, development, yield, and grain quality across various row spacings, planting dates, and prophylactic fungicide application programs in the absence of disease. These data support that early-planted soybean had greater yield than later-planted soybean. No interactions were observed among row spacing, planting date, and fungicide product with respect to yield. Independently, no yield differences were observed regardless of the row spacing or the fungicide product. Regarding quality, soybean planted later resulted in fewer total damaged soybean kernels. These data suggest that row spacing and planting date may not influence soybean’s yield response to prophylactic fungicide. Furthermore, these data also suggest that prophylactic fungicide during pod development may not influence the subsequent grain quality. [ABSTRACT FROM AUTHOR]

Properly terminating furrow irrigation in mid-southern United States (U.S.) crops could reduce irrigation costs, the likelihood of adverse harvest conditions, and agricultural withdrawal from the Mississippi River Valley Alluvial Aquifer (MRVAA). This research was conducted to determine an optimum termination window for furrow-irrigated cotton (Gossypium hirsutum L.) in the mid-southern U.S. The effects of irrigation termination timing on cotton lint yield, net returns, and irrigation water use efficiency (IWUE) were evaluated on a Leeper silty clay loam (fine, smectitic, nonacid, thermic Vertic Epiaquepts) and on a Dundee silty clay (fine-silty, mixed, active, Typic Endoaqualfs). Neither terminating nor continuing to irrigate cotton from cutout (NAWF = 5) up to three weeks past first cracked boll had an effect on lint yield or fiber quality (p ≥ 0.6107). Irrigation water use efficiency declined when water was applied past cutout (p < 0.0001). Results indicate that irrigation in cotton can be terminated at cutout without adversely effecting lint yield and fiber quality if soil water potential does not exceed -130 kPa prior to first cracked boll. Terminating irrigation in cotton at cutout could reduce late season irrigation cost and reduce water withdrawal from the MRVAA thus improving it sustainability. [ABSTRACT FROM AUTHOR]

The article presents the Forty-Ninth Supplement to the Check-list of North American Birds by the American Ornithologists' Union (AOU). It states the changes in the supplement including the additions to the main list for distributional information, the addition of six genera, and the removal of the species Buteogallus subtilis. The article shows the summary of decisions made by the Committee on Classification and Nomenclature of the AOU in North and Middle America for the calendar year 2007.

In the socially monogamous barn swallow, previous studies of individuals in the European subspecies Hirundo r. rustica have shown that a male's tail streamer length is under strong sexual selection and is positively associated with several measures of reproductive success, including a low probability of being cuckolded by other males. The prominence of these results has led to subsequent experimental and correlational investigations of individuals in the phenotypically divergent subspecies H. r. erythrogaster in North America, where it has been shown that male tail streamer length is not as strongly associated with reproductive success as in European populations. We examined relationships between male tail streamer length and patterns of: (1) social mate selection and reproductive success, and (2) extra-pair paternity in 265 progeny of 53 social fathers within a New York barn swallow population. Although tail streamers in this population were sexually dimorphic, male tail streamer length did not predict patterns of mate selection, seasonal reproductive success, or extra-pair paternity. Moreover, in contrast to the strong positive relationships between paternity and male streamer length in European populations, summarized in this paper, we found no positive relationship between a male's paternity of young in the nest he is attending and his tail streamer length in our study population in New York. Our results further corroborate recent suggestions that the function of sexual signals varies geographically in this species, although we await additional experimental analyses on streamer lengths to understand the maintenance of sexual dimorphism in this trait. [ABSTRACT FROM AUTHOR]

The determinants of the geographic distribution of avian hematozoa are poorly understood. Sampling parasites from one avian host species across a wide geographic range is an accepted approach to separate the potential influence of host species distribution from geographic effects not directly related to host species biology. We used polymerase chain reaction to screen samples for hematozoan infection from 490 house finches (Carpodacus mexicanus) collected at 8 sites spanning continental North America. To explore geographic patterns of parasite lineage distributions, we sequenced a portion of the mitochondrial cytochrome b gene of Plasmodium species infecting 77 house finches. We identified 5 distinct Plasmodium haplotypes representing 3 lineages that likely represent 3 species. One lineage was common at all sites where we detected Plasmodium species. The second lineage contained 3 haplotypes that showed phylogeographic structuring on a continent-wide scale, with 1 haplotype common in eastern North America and 2 common in western North America. The third divergent lineage was recovered from 1 individual host. Considered together, the partial phylogeographic structuring of Plasmodium cytochrome b lineages over the range of the house finch suggests that parasite lineage distribution is not solely dependent on host species distribution, and other factors such as arthropod vector competence and distribution may be important.