RMUP‐C5 (Random Mated Upland Population Cycle 5) (Reg. No. GP‐893, PI 652942) is a unique random mated germplasm population of Upland cotton (Gossypium hirsutum L.) involving six cycles of random mating beginning with an 11 parent half diallel. This germplasm was developed through cooperative research by the USDA‐ARS, Mississippi Agricultural and Forestry Experiment Station, North Carolina State Agricultural Experiment Station, and Cotton Incorporated. Parents used in development represented nonrelated or distantly related cultivars or breeding lines from across the U.S. Cotton Belt. The bulked pollen method of pollination was used in the development, and there were six cycles of random mating, with intercrossing of the F1 considered cycle zero. Selfed seed of C5S1 has been released. Changes in correlations between traits among parents, C0, and C5 cycles show that after random mating, the C5 population has recombinations that should be useful for selection and cultivar development. Because this germplasm represents random mating among 11 very diverse breeding programs and includes parents from the major seed breeding companies, this population should be of value to breeders across the U.S. Cotton Belt.

AbstractWe consider the stability of high Reynolds number flow past a heated, curved wall. The influence of both buoyancy and curvature, with the appropriate sense, can render a flow unstable to longitudinal vortices. However, conversely each mechanism can make a flow more stable; as with a stable stratification or a convex curvature. This is partially due to their influence on the basic flow and also due to additional terms in the stability equations. In fact the presence of buoyancy in combination with an appropriate local wall gradient can actually increase the wall shear and these effects can lead to supervelocities and the promotion of a wall jet. This leads to the interesting discovery that the flow can be unstable for both concave and convex curvatures. Furthermore, it is possible to observe sustained vortex growth in stably stratified boundary layers over convexly curved walls. The evolution of the modes is considered in both the linear and nonlinear régimes.

Accurate prediction of soybean growth and development stages is important for soybean farmers and researchers to effectively manage production practices. The objective of this study was to develop accurate time-tables to predict soybean growth and development stages under field conditions. Data from experiments conducted under irrigated conditions at Stoneville, MS from 1998 to 2002 were used. The period of prediction covered the entire growing season from early March to late October, and maturity group (MG) ranged from early III to late V. Tables were constructed based on regression analysis using iterative approximation. Cross validation was performed using randomly selected subsets of the 2002 data set. Accuracies of prediction were similar to model fitting errors. Overall, the error of prediction ranged from 0 to 8 days. It was concluded that soybean phenological stages could be adequately predicted using regression approaches and tables and methodology of table construction can be used by other researchers to build models and tables for their particular situations.

Baseline information on the diversity and population densities of fungi collected from soil debris and cotton (Gossypium hirsutum L.) roots was determined. Samples were collected from Tifton, GA, and Starkville, MS containing cotton field soil treated with the nematicides 1,3-dichloroproprene (fumigant) and aldicarb (granules). A total of 10,550 and 13,450 fungal isolates were collected from these two study sites, respectively. Of this total, 34 genera of plant pathogenic or saprophytic species were identified. Pathogenic root fungi included Fusarium spp. (40% of all isolations), Macrophomina, Pythium, Rhizoctonia, and Sclerotium. Fusarium and Rhizoctonia were the most common fungal species identified and included F. oxysporum, F. verticillioides and F. solani, the three Fusarium species pathogenic on cotton plants. Population densities of Fusarium were not significantly different among locations or tissue types sampled. Macrophomina was isolated at greater numbers near the end of the growing seasons. Anastomosis groups of R. solani isolated from roots and soil debris included AG-3, -4, -7, 2-2, and -13 and anastomosis groups of binucleate Rhizoctonia included CAG-2, -3, and -5. Occurrences and frequency of isolations among sampling dates were not consistent. Fluctuations in the frequency of isolation of Rhizoctonia did not correspond with changes in frequency of isolation of the biological control fungus, Trichoderma. When individual or pooled frequencies of the mycobiota were compared to nematicide treatments, no specific trends occurred between treatments, application methods or rates. Results from this study show that use of 1,3-D and aldicarb in cotton fields does not significantly impact plant pathogenic fungi or saprophytic fungal populations. Thus cotton producers need not adjust seedling disease control measures when these two nematicides are used.

A 2-year (1999–2000) study was conducted at Starkville and Stoneville, MS to determine if the occurrence of the mycoflora varied on Roundup® Ready (transgenic) compared to conventional soybean (Glycine max) cultivars. A total of 7,658 fungal isolates were identified from the pod and seed tissues of four cultivars compared at growth stages R6 and R8. Ninety-nine percent of all fungi isolated were mitosporic fungi and ascomycetes. In both years, total fungal isolates from the two locations were greater from the pod (65%) than from seed (33%) tissues. Isolation frequency from conventional cultivars was 54% compared to 46% for the transgenic cultivars. The most common fungi identified that are reported pathogens of soybean included Alternaria, Cercospora, Cladosporium, Diaporthe, Fusarium and Verticillium spp. When main effects and interactions were compared among the frequency data for the fungal genera, significant differences occurred, but consistent trends were not noted. Isolation frequencies of Diaporthe spp. during the R6 growth stage, were significantly greater on the conventional than on the transgenic cultivars in both years of the study, but only at Starkville. Isolation frequencies from samples taken during the R8 growth stage were similar at both locations in 1999 and 2000.Fusarium spp. isolated at R6 and R8 growth stages from pod and seed tissues were significantly greater on conventional than on transgenic cultivars in 2000. Even though frequencies were often significantly different between the transgenic and conventional cultivars, the data was not consistent between locations, pod and seed tissues, or growth stages. The pod and seed mycoflora of transgenic and conventional soybean cultivars was, therefore, similar in Mississippi.

The southern root-knot nematode (RKN) [Meloidogyne incognita (Kofoid & White)] is a serious pest of cotton (Gossypium hirsutum L.) with detrimental effects being most pronounced on sandy soils that are also infested with the Fusarium wilt pathogen. Varietal resistance is an effective method of managing the RKN/Fusarium wilt complex. In 1970, a high level of RKN resistance was developed in the germplasm line Auburn 623 RNR, but no commercial cultivar has been developed with this near-immunity level of resistance. The objective of this study was to evaluate the mode of inheritance of RKN resistance in M-315 RNR (M-315), a germplasm line with the Auburn 623 RNR source of resistance, and in M78-RNR, a day-neutral version of the race stock line T78. These lines were crossed with M8, an RKN-susceptible cotton line, and with each other. The parental, F1, F2, and backcross generations of these crosses were evaluated in the greenhouse for RKN reproduction 40 d after planting in a Wickham sandy loam soil that had been infested with either 5,000 or 10,000 RKN eggs per pot. The minimum number of genes conditioning resistance in M-315 and M78-RNR was estimated at two and one, respectively. Mendelian analyses indicated that a two gene, one dominant (Mi1) and one additive (Mi2), model fit the data for M-315. The data from crosses with M78-RNR indicated that it had only the dominant Mi1 gene. These data indicate that the Auburn 623 RNR source of RKN resistance should be easily transferable to commercial cultivars.

El acame de raices en maiz dulce (Zea mays L.) es una de las principales causas de perdidas de rendimiento debido a las dificultades que ocasionan la caida de las plantas al momento de realizar la cosecha mecanica. Los genotipos de maiz superdulces, los cuales son muy demandados por su buena calidad comestible son senalados como muy susceptibles al acame (Tracy, 1997). Los objetivos de este estudio fueron evaluar el modo de herencia de la resistencia al acame en una poblacion de maiz “shrunken-2” (sh2) y examinar la posibles relaciones entre caracteristicas morfologicas relativas al acame en condiciones de campo. Dos lineas, R33 (susceptible ) y Mp708 (resistente), fueron cruzadas, posteriormente los progenitores y las progenies resultantes (F1, F2, F3, F4, RC1; R2 y RC3) fueron evaluados en condiciones de campo durante el periodo 1996-1998, se llevaron registros por planta de, resistencia al acame de raices a 2 edades del cultivo, altura de planta, altura de la mazorca y diametro del tallo. El analisis de la media generacional indico que mucha de la variacion genetica para la resistencia genetica al acame de raices fue aditiva. La estimacion de heredabilidad en un sentido estricto para resistencia al acame fue moderada para los anos 1996 y 1998, al menos dos genes influenciaron la resistencia. Resistencia al acame en genotipo sh2 fue mejorada por seleccion de pedigri. Las evaluaciones de acame en campo a las doce semanas, despues de la siembra, diferenciaron mejor los genotipos que las evaluaciones realizadas a las 8 semanas

Theoretical comparisons for quantitativetrait loci (QTL) mapping properties wereconducted among simulated recombinantinbred (RI) populations developed bysingle-hill (SH), complete bulk, and singleseed descent (SSD) procedures by MonteCarlo simulations based on variouspopulation sizes, heritabilities, and QTLeffects. Our simulations includedestimation of QTL effects, QTL positions,and statistical testing power in the RIpopulations by comparing the estimates withpreset values. The simulation resultsshowed that the single hill (SH) bulk andsingle seed descent RI populations weregenerally not significantly different withrespect to quality of estimated QTL effectsand positions. Furthermore, when each RIpopulation had 150 lines, each couldprovide desirable properties for QTLmapping. The results implied that a SH RIpopulation consisting of 75 or moreF2-derived families with two lines perfamily (corresponding population size of150 or above) was appropriate for QTLmapping and was not significantly differentthan a SSD RI population of 150. Thus, theSH method could be used to develop largenumbers of RI lines for achieving betterresults in QTL mapping. Simulations alsoshowed that there was no significantdifference between means using SH methodswith 10 and 100 fruits per family. However, RI populations developed by thecomplete bulk method where F2identities are lost were not suitable forQTL mapping.

Genes for improved yield and fiber quality are available in Australian cultivars and wild accessions of cotton (Gossypium hirsutum L.); however, their combining ability with U.S. cultivars is unknown. We evaluated combining ability and inheritance of yield and fiber traits among nine diverse cotton lines: two cultivars developed in Australia, two experimental lines from wild accessions, and five U.S. cultivars. Parents and F 2 ’s from a half-diallel cross were grown in Leeper silty clay loam and Marietta sandy clay loam in 1999 and 2000. F 2 hybrids had higher lint yield, heavier bolls and longer fibers than parents. Variance components and genetic effects were calculated utilizing an extended additive dominance model with genotype by environment interaction effects using a mixed norm quadratic unbiased estimation analysis. Parents varied in genetic combining ability (GCA). ‘Fibermax 832’, developed in Australia, was the best in GCA for yield and fiber quality. ‘Stoneville 474’ was the best in GCA for yield. Experimental line, B 1388, was good in GCA for fiber strength, although other properties suffered. ‘Paymaster 1560’ exhibited good GCA ability for yield and fiber length. ‘Fibermax 975’ exhibited good GCA for fiber length. Lint yield, boll size, and fiber elongation had approximately equal additive and dominance genetic effects. Lint percentage and fiber strength exhibited primarily additive genetic effects. Micronaire and length exhibited primarily dominance genetic effects. A significant residual component of the phenotypic variance was present for each trait except lint percentage. The Australian cultivars and wild accessions can combine with cultivars from U.S. breeding programs to provide genes for fiber and/or yield improvement.

F2 hybrid cultivars continue to occupy a small portion of the cotton (Gossypium hirsutum L.) production are in the United States, but occupy a larger proportion of the production area in some other countries. Sixty-four F2 hybrids resulting from crosses of four commercial cultivars and 16 pest-resistant germplasm lines were evaluated for five fiber and four yield traits in four environments at Mississippi State, MS. An additive-dominance genetic model was employed for these traits. The minimum norm quadratic unbiased estimation (MINQUE) method was used with a mixed model approach for estimating genetic variance and covariance components and for predicting genetic correlations. This study investigated genetic variances, heritabilities, and genetic and phenotypic correlations between agronomic and fiber traits among these 64 F2 hybrid populations and discussed the usefulness of these populations for use as hybrids or for selections for pure lines.

Two F2 populations of cotton (Gossypium hirsutum L.) from the crosses of HS46 x MARCABUCAG8US-1-88 (MAR) and HS46 x Pee Dee 5363 (PD5363) were characterized for restriction fragment length polymorphisms (RFLPs) using DNA probes. Seventy-three probe/enzyme combinations were used in the HS46 x MAR population analysis, which resulted in 42 informative polymorphic fragments. These 42 moleclar markers represented 26 polymorphic loci, which consisted of 15 codominant and 11 dominant (+/-) genotypes. Chi-square analyses of these loci fit expected genotypic ratios of 1∶2∶1 and 3∶1, respectively An analysis of these loci with the MAPMAKER program resulted in the establishment of four linkage groups A, B, C, and D with 4,2,2, and 2 loci, respectively, as well as 16 unlinked loci. Six probe-enzyme combinations were assayed on the HS46 x PD5363 population, which resulted in 11 informative polymorphic fragments. These 11 fragments represented 6 polymorphic loci, 1 dominant (+/-) and 5 codominant genotypes. The MAPMAKER analysis of these loci yielded 2 linked loci. Thus, a total of 53 polymorphic fragments and 32 polymorphic loci, representing five linkage groups, were identified among the two families.

Crop ScienceVolume 35, Issue 3 cropsci1995.0011183X003500030057x p. 939-939 Registration of Cultivars Registration of ‘DeSoto’ Tall Fescue C. E. Watson Jr., Corresponding Author C. E. Watson Jr. n/a@.dne MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Corresponding author.Search for more papers by this authorS. D. Linscombe, S. D. Linscombe MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorS. D. McLean, S. D. McLean MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorC. A. Meurer, C. A. Meurer MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorM. A. Smith, M. A. Smith MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorD. S. Wofford, D. S. Wofford (former graduate assistants)Search for more papers by this authorJ. W. Baswell, J. W. Baswell (retired)Search for more papers by this author C. E. Watson Jr., Corresponding Author C. E. Watson Jr. n/a@.dne MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Corresponding author.Search for more papers by this authorS. D. Linscombe, S. D. Linscombe MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorS. D. McLean, S. D. McLean MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorC. A. Meurer, C. A. Meurer MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorM. A. Smith, M. A. Smith MAFES Res. Support Units, Box 9653,, Mississippi State, MS, 39762Search for more papers by this authorD. S. Wofford, D. S. Wofford (former graduate assistants)Search for more papers by this authorJ. W. Baswell, J. W. Baswell (retired)Search for more papers by this author First published: 01 May 1995 https://doi.org/10.2135/cropsci1995.0011183X003500030057xCitations: 1 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume35, Issue3May–June 1995Pages 939-939 RelatedInformation

In situ airborne measurements of the turbulent flux and mean values for O3, CO, and CH4 were obtained in the boundary layer over selected wetland systems in Alaska. These measurements were obtained in July–August 1988 as part of the NASA Global Tropospheric Experiment Program's Arctic Boundary Layer Expedition (ABLE 3A). The flux measurements obtained from this study provide information on the source/sink distribution of O3 and CH4 over the Yukon‐Kuskokwim Delta (YKD) and Alaskan North Slope (ANS) regions of Alaska. The source/sink distribution over the YKD is qualitatively correlated with surface vegetation type, identified from multispectral scanner imagery. Direct measurements of the spatial variation in the CH4 source strength were obtained over the YKD. The CH4 source strength over the YKD ranged from 25 to 85 mg m−2 d−1 during a flux survey flight which spanned a considerable portion of the YKD. A spatially averaged, seasonally adjusted source strength of 51 mg m−2 d−1 was established for the YKD. Indirect CH4 flux estimates obtained over the ANS indicate a much lower (∼10 mg m−2 d−1) source strength. The global CH4 emissions from tundra were estimated to be 44 Tg/a based on (1) the spatially averaged source strength obtained over the YKD, (2) current estimates of the global coverage of tundra, and (3) assuming a similarity between other tundra areas and that of the YKD. This estimate is taken to be an upper limit due to possible sampling inadequacies and because the spatial distribution of the CH4 source function over the YKD may not extend to all other northern wetland regions. This estimate is, however, in reasonable agreement with previous estimates. Airborne CO flux measurements over the YKD indicated low negative flux values over the coastal areas, while some positive fluxes were observed in the inland, sparsely forested regions. An inspection of the cospectrum of CO with vertical velocity for sample runs in coastal areas indicated a minimum at wavelengths which were noticeably shorter (70–400 m) than where any prominent feature could be found for similar cospectrums of heat, moisture, O3, or CH4 with vertical velocity. Similar analyses for transects over inland areas indicated occasional peaks in this same, short wavelength band. These features indicate the possibility of in situ photochemical destruction/production of CO, although the identification of a possible chemical mechanism was not attempted at this time. Tundra surfaces are estimated to be responsible for ∼32% of the total deposition loss of O3 poleward of 60°N. Data from the airborne O3 flux measurements made during this study indicate similar values of Rc for the ANS and YKD regions.

White clover was compared against five rates of nitrogen fertilizer (NH4NO3) as sources of N for tall fescue over a 3 year period. The white clover-tall fescue combination produced as much forage as tall fescue alone fertilized with 132–198 kg N ha−1 in the first 2 years. However, in the third year the white clover-tall fescue combination only produced as much forage as tall fescue alone fertilized with 0–66 kg N ha−1 as a result of a large decline in the stand of white clover. Tall fescue alone showed a significant response to fertilization up to the maximum rate of 264 kg N ha−1. Tall fescue fertilized with 264 kg N ha−1 produced significantly more forage than the white clover-tall fescue combination in all 3 years.

Cochliobolus sativus (Ito and Kurib.) Drechsl. ex Dastur is a major foliar pathogen of tall fescue (Festuca arundinacea Schreb.) which can greatly reduce the quantity and quality of forages available for animal consumption. A greenhouse screening program was initiated to determine the inheritance of resistance to C. sativus in tall fescue over several cycles of mass selection. Resistance to C. sativus in four tall fescue cultivars was increased with 2–3 cycles of mass selection. Realized heritabilities were low to moderate (0.04 to 0.58) indicating that environmental influences on the expression of resistance are quite high. Variances were unchanged by selection, indicating that further improvement should be possible. However, progress with mass selection can be expected to be slow. Lesion size was decreased in each cultivar by selecting for lesion coverage. Lesion size, being independent of inoculum load and therefore less subject to environmental variation, should be considered as an additional selection criteria to improve the rate of progress.

Crop ScienceVolume 22, Issue 6 cropsci1982.0011183X002200060050x p. 1260-1260 Registration of Crop Cultivar Registration of Fresa Strawberry Clover1 (Reg. No. 38) A. A. Baltensperger, A. A. BaltenspergerSearch for more papers by this authorC. E. Watson, C. E. WatsonSearch for more papers by this authorM. A. Smith, M. A. SmithSearch for more papers by this authorS. D. McLean, S. D. McLeanSearch for more papers by this authorR. E. Gaussoin, R. E. Gaussoin Professor of agronomy professor emeritus of agronomy, research assistant, research aide and research assistant Dep. of Crop and Soil Sciences, New Mexico State Univ., Las Cruces, NM 88003Search for more papers by this author A. A. Baltensperger, A. A. BaltenspergerSearch for more papers by this authorC. E. Watson, C. E. WatsonSearch for more papers by this authorM. A. Smith, M. A. SmithSearch for more papers by this authorS. D. McLean, S. D. McLeanSearch for more papers by this authorR. E. Gaussoin, R. E. Gaussoin Professor of agronomy professor emeritus of agronomy, research assistant, research aide and research assistant Dep. of Crop and Soil Sciences, New Mexico State Univ., Las Cruces, NM 88003Search for more papers by this author First published: 01 November 1982 https://doi.org/10.2135/cropsci1982.0011183X002200060050xCitations: 4 1 Registered by the Crop Sci. Soc. Am. Contribution from the New Mexico Agric. Exp. Stn. Journal Article No. 930 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume22, Issue6November–December 1982Pages 1260-1260 RelatedInformation

Crop ScienceVolume 21, Issue 3 cropsci1981.0011183X002100030034x p. 474-475 Registration of Crop Cultivar Registration of Marshall Annual Ryegrass1 (Reg. No. 72) B. L. Arnold, B. L. ArnoldSearch for more papers by this authorC. E. Watson Jr., C. E. Watson Jr.Search for more papers by this authorN. C. Edwards Jr., N. C. Edwards Jr. Superintendent, North Mississippi Branch Exp. Stn. Holly Springs, MS 38635; assistant professor of agronomy, Mississippi State Univ., Mississippi State, MS 39762; associate agronomist, Brown Loam Branch Exp. Stn., Raymond, MS 39152.Search for more papers by this author B. L. Arnold, B. L. ArnoldSearch for more papers by this authorC. E. Watson Jr., C. E. Watson Jr.Search for more papers by this authorN. C. Edwards Jr., N. C. Edwards Jr. Superintendent, North Mississippi Branch Exp. Stn. Holly Springs, MS 38635; assistant professor of agronomy, Mississippi State Univ., Mississippi State, MS 39762; associate agronomist, Brown Loam Branch Exp. Stn., Raymond, MS 39152.Search for more papers by this author First published: 01 May 1981 https://doi.org/10.2135/cropsci1981.0011183X002100030034xCitations: 26 1 Registered by the Crop Sci. Soc. of Am. Contribution of the Mississippi Agric. and Forestry Exp. Stn. Mississippi State, MS 39762. Paper No. 4628. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume21, Issue3May–June 1981Pages 474-475 RelatedInformation

Fifteen single-crosses of a six-parent diallel of tall fescue (Festuca arundinacae, Schreb.) were evaluated for perloline concentration, N content, and in vitro digestibility. The crosses were planted at Corvallis, Oregon, and Columbia, Missouri, and harvested on 8 Apr. and 22 Sept. 1975 at Corvallis and on 16 Oct. 1975 at Columbia. The data were analyzed as two experiments. Experiment I consisted of the two harvests at Corvallis and experiment II consisted of the harvests of 22 September at Corvallis and 16 October at Columbia. Both experiments were analyzed for perloline concentration and N content, but only experiment II was analyzed for in vitro digestibility. General (GCA) and specific combining ability (SCA) were significant sources of variation for perloline concentration. SCA indicated some nonadditive gene action for perloline concentration. There were differences between environments as well as genotype ✕ environment interactions in both experiments. GCA was a significant source of variation for nitrogen content in each experiment. However, environmental differences were larger than genetic differences. No differences were found among the crosses for in vitro digestibility, but there was a rather large difference between the two locations. It appeared that digestibility could be improved more by management than by selection in this population.