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Yield monitor data are being used for a variety of purposes including conducting on-farm studies, assessing nutrient balances, determining yield potential, and creating management zones. However, standardization of raw data processing is needed to obtain comparable data across fields, farms, and years. Our objective was to evaluate the impact of data cleaning protocols on corn (Zea mays L.) grain and silage yield data at the whole field (with and without headlands) and within field (soil map unit) scales. Corn silage data from 145 fields (three farms) and grain data from 88 fields (three farms) were processed. Comparisons were made to evaluate yields among three levels of cleaning: (i) none; (ii) automated cleaning ("Auto") with filter settings derived for 10 fields per farm; and (iii) automated cleaning with manual inspection for unrepresentative patterns, after the automated cleaning step was completed ("Auto+"). The Auto+ cleaning process was conducted separately by three individuals to evaluate person-to-person differences. Spatial Management System software was used to read raw data and transfer to Ag Leader format. Yield Editor software was used to clean data (Auto and Auto+). Results showed the necessity of data cleaning, especially for corn silage. However, considering less than 5% deviation between methods at three spatial scales, the Auto and Auto+ cleaning resulted in similar output, as long as (i) each field or subfield included at least 100 harvester measurement points, and (ii) a moisture filter was applied for corn silage data. [ABSTRACT FROM AUTHOR]

Current New York land grant university fertility guidelines for corn (Zea mays L.) recommend the use of 22 to 34 kg N ha-1 of band-applied starter fertilizer. On-farm research was conducted in 2006 and 2007 on a western New York dairy farm with an alfalfa (Medicago sativa L.)--corn rotation to evaluate the need for starter N for corn in regularly manured fields. In 2009, the study was expanded to include 21 fields varying in soil type, manure history, and soil N supply potential as expressed by the Illinois soil N test (ISNT). At the western New York farm, there was no increase in corn silage yield or quality with starter N use in first-, second-, or fourth-year corn fields. The results of the statewide assessment also showed that for fields with optimal ISNT-N, manure could replace starter N without a decline in corn silage yield or quality. Starter N fertilizer application was needed for optimal yield in fields deficient or marginal in ISNT-N and without a manure history. For such fields, manure could replace the need for starter N as long as sufficient N was applied with the manure, indicated by corn stalk NO test (CSNT) results between 750 and 2000 mg NO3-N kg-1. A response of silage yield to starter N was common when CSNT-N was <750 mg NO3-N kg-1. We conclude that manure can replace the need for starter N, but rates should be adjusted to obtain CSNT values between 750 and 2000 mg kg-1. [ABSTRACT FROM AUTHOR]

Immunolocalizations in whole mounts of walled cells require an empirically derived, species-specific permeabilization strategy. Particularly when cell walls are recalcitrant to enzymatic digestion, as with many fungi, permeabilization can degrade structure and reduce or destroy antigenicity. To avoid these potential problems, hyphae were freeze-substituted, embedded in a methacrylate resin, thick-sectioned and de-embedded prior to immunolocalization. The cytoskeletal proteins actin and β-tubulin were labelled via indirect immunofluorescence in hyphal tip cells of Magnaporthe grisea, and Trichoderma viride. Well-defined punctate actin plaques were observed concentrated at the subapical cell periphery in both species, especially near the hypha-substratum interface. In addition, a Spitzenkörper core and less intense cytoplasmic binding were observed. Immunoelectron microscopy confirmed localization of actin in the Spitzenkörper core and filasomes. β-Tubulin was immunolocalized as both linear arrays and punctate dots via epifluorescence microscopy. Analysis of 450-550-nm-thick serial sections contributed to improved resolution by the reduction of out-of-focus blur. Overall, the freeze substitution methacrylate de-embedment technique provided superior preservation, serial section analysis, and improved antibody penetration and resolution of these cytoskeletal proteins. The technique will be a valuable tool for use with a variety of reporter molecules in cells of fungi. [ABSTRACT FROM AUTHOR]