bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Row Spacing and Cotton Cultivars on Seedling Diseases, Verticillium Wilt, and Yield1
Authors: Minton Earl B. 
Published: July 2010

Cotton (Gossypium hirsutum L.) cultivars ‘Rilcot 90’ (susceptible to Vertkillium wilt) and ‘Paymaster 266’ (resistant to Verticillium wilt) were grown in one, two, and four rows per bed spaced 100 cm apart to determine the effects of cultivars and row spacings on seedling diseases, Verticillium wilt, and yield. Each treatment was applied to the same plot for 3 consecutive years. Plant stands increased with close row spacings but were not directly related to the seeding rates. The prevalence of foliar symptoms of Verticillium wilt was higher in Rilcot 90 than in Paymaster 266, but the percentage decreased with close row spacing. The number of diseased plants of each cultivar was higher with closer row spacing but did not increase directly with plant populations. Lint yield was highest in plants having two rows per bed and lowest in those having one row per bed, but the differences were not significant. The high moisture level maintained during the growing season provided good conditions for disease evaluations but probably reduced lint yield.In the 4th year, each plot was halved. Seeds of the wilt‐susceptible ‘Lockett 4789A’ and of the wilt‐resistant ‘Paymaster 909’ were planted in one half of each plot in rows 100 cm apart. Stands were reduced slightly by seedling diseases. The prevalence of Verticillium wilt was lower when each cultivar was grown after Paymaster 266 rather than Rilcot 90. Close row spacing during the previous 3 years did not significantly increase the prevalence of Verticillium wilt. A disease‐resistant cultivar should be grown at high plant populations to minmize losses from Verticillium wilt and to maximize lint yields.
Vegetative Propagation of Temperate Forage Grasses through Callus Culture1
Authors: Lo P. F. , Chen C. H. , Ross J. G. 
Published: July 2010

Five temperate forage grass species, creeping foxtail (Alopecurus arundinaceus Poir.), crested wheatgrass (Agropyron cristatum (L.) Gaertn.), green needlegrass (Stipa viridula Trin.), smooth bromegrass (Bromus inermis Leyss.) and western wheatgrass (Agropyron smithii Rydb.) were cultured in vitro. Callus was initiated from segments of young inflorescences of each species cultured in the dark at 25 C on Linsmaier and Skoog (RM) or Gamborg, Miller, and Ojima (BS) medium supplemented with 5 mg of 2,4‐dichlorophenoxyacetic acid (2.4‐D) combination with 0 or 0.2 mg kinetin/liter. All of the calluses subcultured on RM medium unsupplemented with hormones in the dark at 25 C developed plantlets via organogenesis. An addition of 1 mg kinetin/liter to the basal medium enhanced shoot initiation in calluses of western wheatgrass, green needlegrass, and creeping foxtail. Regenerated plants were subsequently established in soil.Albinism was noted among the regenerated plantlets of smooth bromegrass, creeping foxtail, crested wheatgrass, and green needlegrass. The relative frequency of albino plantlets emerging from a callus tended to increase with age of the subculture. Albinism was reduced in calluses differentiating on RM medium containing 1 mg kinetin/ liter, possibly due to improved plastid formation.All of the calluses were maintained on RM medium supplemented with 5 mg 2,4‐D/liter. Improved growth of green needlegrass callus was obtained by supplementing the above medium with 0.5 mg of kinetin/liter.Two warm‐season grasses, big bluestem and Indiangrass, have previously been shown to respond to the same general tissue culture methods used in the present study. This suggests that these methods may have general applicability for forage grass species.
Preharvest Desiccants for Rice1
Authors: Eastin E. F. 
Published: July 2010

Preharvest desiccation of rice (Oryza saliva L.) would improve timeliness of harvest and allow more efficient and faster combining of the grain. Field studies to determine the suitability of diquat (6,7‐dihydrodipyrido [1,2‐α:2′,1′‐c]pyrazinediium ion), glyphosate [N‐(phosphonomethyl)glycine], paraquat (1,1′‐dimethyl‐4,4′‐bipyridinium ion), and sodium chlorate as preharvest desicants for rice were conducted for 2 years. Diquat at 0.28 kg/ha and paraquat at 0.14 kg/ha resulted in good leaf desiccation in 2 days under the hot cloudy conditions of the studies. Three days were required for desiccation when diquat at 0.14 kg/ha was applied, while 4 days were required when sodium chlorate at 5.04 kg/ha was applied. Glyphosate at rates up to 1.12 kg/ha did not adequately desiccate rice leaves in 7 days under the conditions of this study. When applied to rice with grain moisture of 22%, diquat at 0.56 kg/ha, paraquat at 0.14 kg/ha, and sodium chlorate at 5.04 kg/ha significantly reduced grain moisture 3 days after application. Diquat at 0.14 kg/ha and glyphosate at 1.12 kg/ha required 7 days to reduce grain moisture. Only paraquat at 0.14 kg/ha 7 days after application to 16.5% moisture rice reduced grain moisture.Whole kernels after milling were slightly reduced by diquat at 0.28 and 0.56 kg/ha, paraquat at 0.14 kg/ha and sodium chlorate at 5.04 kg/ha, all applied to 25% grain moisture rice 7 days before harvest. None of the desiccants evaluated reduced grain yield, seed germination, or 1,000 grain weight. These results indicate that diquat, paraquat and sodium chlorate may have potential as preharvest desiccants for rice.
Genetics of Vegetative Stand Establishment Characters in Reed Canarygrass Clones1
Authors: Casler M. D. , Hovin A. W. 
Published: July 2010

The objectives of this study were to evaluate characters related to vegetative stand establishment of reed canarygrass (Phalaris arundinarea L.), their heritabilities, interrelationships, and responses with plant age. Characters were evaluated for 22 clones and 12 full‐sib families grown in the field and included plant height, plant maturity, axillary shoot length, and node diameter. Vegetative stand establishment characters evaluated in the greenhouse included percentage of rooted nodes (RN%) and number of adventitious roots produced per node (R/N). In the field, chopped culms were covered with soil to determine number of plants produced per culm, number of plants produced per fresh weight of culms (P/W), percentage of nodes establishing plants, and number of tillers per plant (T/P). Axillary shoot length (SL) was measured on plants grown in four environments and all other characters were measured on plants grown in two environments.Narrow‐sense heritabilities of R/N, RN%, P/W, and T/P were estimated by midparent‐progeny regressions and ranged from 0.36 to 0.78. Broad‐sense heritability estimates ranged from 0.53 to 0.79 based on clones and 0.65 to 0.79 based on full‐sib families.Comparisons among previously established clonal classes of vegetative stand establishment capacity were significant for R/N. Mean R/N was significantly higher for clones classified as high compared to clones classified as intermediate and was lower for eiones classified as low compared to all other clones. Mean R/N and RN% were highly correlated (r = 0.85; P < 0.01), but variation among clonal classes for RN% was nonsignificant. Mean R/N and RN% were significantly greater in a 4‐year‐old stand compared to a 1‐year‐old stand. Basal nodes had higher mean R/N than did apical nodes. Vegetative propagation of reed canarygrass should, if possible, be done with initial growth forage from the lower portion of the canopy of stands at least 3 years old. Genotypes with improved establishment capacity can be identified by their root and shoot production potential in the greenhouse.
Comparison of Artificial and Natural Selection in American Pima Cotton under Different Environments1
Authors: Feaster C. V. , Young E. F. , Turcotte E. L. 
Published: July 2010

The effectiveness of artificial vs. natural selection for improving lint yield and other traits in American Pima cotton (Gossypium barbadense L.) when grown in predictable environments was evaluated at low and high elevations. A cross was made between ‘Pima S‐3,’ adapted to the less fertile soils at high elevations, and ‘Pima S‐4,’ adapted to low elevations and to the more fertile soils at high elevations. F2 through F8 populations from this cross were grown at one low‐elevation and two high‐elevation locations. These populations were subjected to natural selection by bulking all plants to form the next generation, or to artificial selection by bulking only selected plants to form the next generation. Phenotypic differences for lint yield, plant height, and fruiting height among plants within the succeeding generations were greatest at Phoenix, next greatest at Safford, and least at El Paso. Therefore, selection of genotypicaliy productive plants was most effective at Phoenix, somewhat less effective at Safford, and the least effective at El Paso.Artificial‐ vs. natural‐selection cycles 0 (F2), 3, and 6 from each of the three locations were evaluated at all locations. The populations developed by artificial selection at a given location tended to yield more than naturally selected populations at that location, with the greatest advantage at Phoenix, next greatest at Safford, and no advantage at El Paso. Likewise, among locations, natural selection had the most influence on yield potential at Phoenix. In some years, the artificially selected populations from one location tended to yield well at the other locations, but no population yielded well at all‐three locations in both years. Selection for improvement of traits such as lint yield in the environment where the selected population will be utilized was effective. However, if the Pima improvement program were confined to one location, Phoenix appears to be the best of the three locations. At Phoenix, the magnified expression of productivity, and fruiting‐ and plant‐height differences would permit the selection of genotypes that would be productive at each elevation of the American Pima Belt.
Effect of Genotype and Tuber Size on Eye Number and Blind Seedpieces in Potato1
Authors: Reeves Alvin F. , Hunter James H. 
Published: July 2010

Samples of 60 to 200 tubers from each of 10 potato cultivars (Solanum tuberosum, L.) and six different unnamed clones from the Maine Potato Breeding Program were hand‐sized and the number of eyes per tuber ascertained. Eye number showed significant positive correlation with tuber size. Each of three size categories differed significantly from the other two in mean eye number. Although several clones and cultivars differed significantly in mean eye number, the relationship of eye number to tuber size was similar for all clones and cultivars tested.Larger samples of the six unnamed clones were sized and cut by machine. The percentage of blind seedpieces (pieces with no eyes) was then determined for the three tuber size categories. In general, larger tubers produced more blind seedpieces. Clones with low eye numbers produced four times as many blind seedpieces in all size categories as clones with high eye numbers.
Influence of Semidwarfism and Genetic Background on Stand Establishment of Wheat1
Authors: Allan R. E. 
Published: July 2010

The objective of this study was to determine the influence of genetic backgrounds and semidwarf plant height genes (Rht1 and Rht2) on wheat (Triticum aestivum L.) stand establishment. Final stands (FS) and emergence rate indexes (ERI) were measured in 2 test years for eight populations, each including 15 isolines of two‐gene scmidwarf, one‐gene semidwarf, and normal heights. In 62 of 64 comparisons, the FS and ERI values of two‐gene semidwarfs were significantly lower than those of their one‐gene semidwarf or normal counterparts. One‐gone semidwarfs usually had lower FS and ERI values than their normal counterparts and these differences were significant for 23 of 32 comparisons.Two‐gene and one‐gene semidwarfs and normal isolines of the eight populations averaged 38.9, 51.9 and 61.0 seedlings per plot (FS), respectively; the average ERI values of these three height classes for all populations were 89.7, 161.2, and 228.2, respectively. However, highly significant differences for both FS and ERI occurred among the eight populations during both test years. Variations due to height classes, test years, populations, and their interactions were also significant.Results indicate that the Rht1 and Rht2 genes for semi‐dwarfism either reduce stand establishment capabilities or are genetically related to genes which do. The extent to which semldwarfism influences FS and ERI was appreciably altered by different genetic backgrounds. The backgrounds of the ‘Omar’ and ‘Golden’ cultivars minimized adverse effects of semidwarfism on FS and ERI, whereas the backgrounds of ‘Brevor,’ ‘Burt,’ ‘Itana,’ and ‘Marled’ cultivars had especially adverse or erratic effects on both stand establishment traits.
Inheritance of β‐Amylase Nulls in Soybean Seed1
Authors: Hildebrand D. F. , Hymowitz T. 
Published: July 2010

The soybean [Glycine max (L.) Men.] cultivar ‘Altona’ lacks β‐amylase activity (AM null 1) and the Sp1b seed protein electrophoretic band. Altona also has a genotype with β‐amylase activity and the Sp1b band (Rf 0.42). The cultivar ‘Chestnut’ lacks detectable β‐amylase activity (AM null 2), but it produces the Sp1a seed protein electrophoretic band (Rf 0.36). Seed from reciprocal crosses of Altona (AM null 1) and ‘Amsoy 71’ (Sp1a), the cross Altona (Sp1b) ✕ Altona (AM null 1), the cross Altona (AM null 1) ✕ ‘Corsoy’ (Sp1b), reciprocal crosses of Chestnut (AM null 2) and Altona (Sp1b), reciprocal crosses of Chestnut (AM null 2) and Amsoy 71 (Sp1a), and the cross Chestnut (AM null 2) ✕ Altona (AM null 1) were analyzed to determine the inheritance of AM nulls 1 and 2 relative to Sp1a and Sp1b.The F2 and F3 data establish that AM null 1 is recessive to the codominant alleles Sp1a and Sp1b for both β‐amylase activity and the seed protein band. AM null 2 is recessive to Sp1a and Sp1b for β‐amylase activity but codominant to Sp1b for the seed protein band. The symbols sp1 are proposed for the AM null 1 allele and Sp1an for the AM null 2 allele.
Performance of Paired Nectaried and Nectariless F3 Cotton Hybrids1
Authors: Meredith William R. 
Published: July 2010

Amino acids and sugars are removed from cotton, Gossypium hirsutum L., nectaries in large amounts by various insects. Nectariless [2(ne1ne2)] cottons conceivably could utilize this photosynthate to increase yield or fiber quality. The possibility of identifying superior nectariless populations motivated this study. The objectives were to: 1) evaluate a method of detecting nectariless populations that contained favorable interactions of yield and fiber quality with nectariless genes and 2) determine the magnitude and frequency of occurrence of these favorable interactions.Nectaried (Ne) and nectariless (ne) hybrid populations were derived from crosses of DES 24‐8ne with 19 diverse strains (S) at Stoneville, Mississippi. In 1976, 8 pairs and in 1977, 11 pairs of Ne and ne F3 hybrids were each grown in six replications at two Stoneville locations. Averaged over both years, nectaried plants had 1.8% larger seeds and 1.6 and 0.9% longer fiber (50 and 2.5% span length, respectively) than nectariless plants. In 1977, boll size in nectaried plants was 1.5% larger than in nectariless ones. No other significant differences or trends were detected. These results reinforced previous studies indicating no strong deleterious association between nectariless and yield and fiber properties. No significant Ne vs. ne ✕ S interactions were detected for lint yield, but small significant interactions were detected for lint percentage in 1977 and 2.5% span length in both years. Breeders should therefore not expect any large increases in yield due to the ability of nectariless plants to utilize the nectar photosynthate for agronomic purposes. However, the detection of favorable small interactions for lint percentage and fiber length suggested small advances in germplasm development.
A Search for Condensed Tannins in Annual and Perennial Species of Medicago, Trigonella, and Onobrychis1
Authors: Goplen B. P. , Howarth R. E. , Sarkar S. K. , Lesins K. 
Published: July 2010

Bloat of ruminant animals feeding on fresh, green alfalfa (Medicago sativa L.) is caused by high levels of soluble plant proteins which act as foaming agents. It is postulated that bloat‐safe cultivars may be bred by introducing condensed tannins (flavolans) which would act as protein precipitants to preclude foam formation and consequent bloat. Using the vanillin‐HCl spot test, large populations of alfalfa were screened for tannins. These included several accessions, cultivars, and breeding populations. Extensive screening of 2n M. falcata L. and 4n M. sativa treated with the chemical mutagens ethyl methanesulfonate or ethyleneimine failed to reveal any mutations for tannins. Screening of 33 species (a total of 86 accessions) of annual Medicago was negative. Similarly, screening of 28 species (a total of 92 accessions) of perennial Medicago was also negative. Examination of 30 species (46 accessions) of the closely related Trigonella genus did not reveal any tannin‐containing plants. On the other hand, testing of 123 accessions of 10 species of Sainfoin (Onobrychis) showed that all plants examined within this bloat‐safe genus contained high levels of tannins.Several of the common pasture legumes, including both bloat‐causing and bloat‐safe types, were examined for tannins in leaf tissue, flower (petal) tissue and seeds. All of these legumes except alfalfa and cicer milkvetch (Astragalus cicer I.,) contained tannins in petal tissue. All of the legumes, including alfalfa, contained tannins in seedcoat tissue except that of a homozygous recessive, white‐seeded strain of alfalfa.The implications of breeding for tannins to provide a bloat‐safe alfalfa are discussed.
Development of Root‐branching in Three Alfalfa Cultivars1
Authors: McIntosh M. S. , Miller D. A. 
Published: July 2010

A study of rooting habit of three winter‐hardy alfalfa, Medicago sativa L., cultivars was conducted at the Univ. of Illinois Agronomy South Farm. The objectives were to study the rooting habit of three high‐yieldlng, winterhardy alfalfa cultivars during their first growing season in order to determine if any differences in root branching exist among the cultivars and to estimate phenotypic correlations between the branching‐root habit and other agronomic characters. ‘Saranac,’ ‘Victorian’ and ‘Iroquois’ alfalfa plants were sampled eight times during the first growing season. Root and top growth of the alfalfas were measured and rooting habit was evaluated on a scale where l=tap‐rooted and 5=branching‐rooted.The majority of the plants in all three cultivars were predominantly tap‐rooted, although there was a considerable amount of variation for rooting habit within cultlvars. Nine percent of the plants were classified as branching‐rooted by the last harvest. The mean root branching scores, which fluctuated during the growing season, ranged from 1.9 to 2.5. The branching.root habit in all three cultivars was positively correlated with top (r=0.27 to 0.53, significant at the 0.01 level) and root (r=0.36 to 0.57, significant at the 0.01 level) dry weights. The results indicated that these cultivars could be used as germplasm sources in developing high‐yielding, branching‐rooted alfalfa.
Effectiveness of Single Plant Selection During Successive Generations of Inbreeding in Soybeans1
Authors: Wilcox J. R. , Schapaugh W. T. 
Published: July 2010

Phenotypically superior plants were selected in the F2 through the F4 generations in 12 soybean [Glycine max (L.) Merr.] crosses, three among superior soybean cultivars and nine between those cultivars and plant introductions. Seed from the selected plants within each cross was composited to form the bulk for the succeeding generation of selection. The objective was to determine how effective single plant selection would be in the heterogeneous bulk populations.Visual selection for superior plants from the heterogeneous populations had no effect on seed yield. selected F4 bulks matured later than the unselected F2 populations in 7 of the 12 crosses and were taller than unselected F2 populations in 9 of the 12 crosses. Selected F4 bulks from crosses among the three cultivars lodged more than their F2 progenitors; however, only three F4 bulks from crosses between cultivars and plant introductions lodged more than the unselected F2 populations. The data indicated that even though tall, late maturing plants in these bulk populations appeared to be phenotypically superior, they were not superior in yield to the unselected bulks.
Duration of Grain Filling and Kernel Weight of Wheat as Affected by Temparature1
Authors: Wiegand C. L. , Cuellar J. A. 
Published: July 2010

Once kernels are set, cereal grain yields are proportional to kernel weight. Thus environmental effects on kernel size merit better understanding as a source of yield variability.Plant phenology was observed, environmental conditions were monitored, and kernel weights were determined for wheat during two seasons at 26°N. Lat. These observations provided data sets for relating mean daily temperature during grain filling (from the beginning of flowering to mealy ripeness of the kernels) to kernel weight and to duration of grain filling.The data indicate a 3.1 day shortening of grain filling per degree C increase in mean daily air temperature during grain filling which compares with 2.8 days C‐1 for seven studies reported in the literature. Kernel weight in this study decreased 2.8 mg kernel ‐1 C‐1 compared with 1.5 mg for each degree C increase in temperature for seven studies in the literature.We concluded that temperature is pacing plant senescence and that shortening the duration of grain filling is its common manifestation in commercial winter and spring wheats. Temperature, when in excess of about 15 C, apparently explains the dependence of 1,000 kernel weight on grain filling duration.The findings imply that genetic variability in plant senescence and grain filling rates need to be searched for and exploited to help stabilize the kernel size component of yield.
Variation Among Alfalfa Cultivars for Indices of Nitrogen Fixation1
Authors: Hoffman David , Melton Bill 
Published: July 2010

Alfalfa (Medicago sativa L.) cultivars with increased nitrogen fixation potential would be beneficial. The desirability of existing cultivars as genetics source material for a breeding program to accomplish this objective has not been reported.Ten alfalfa cultivars contrasting in fall dormancy, date of release, and germplasm origin were evaluated as 10‐week‐old seedlings for indices of N2‐fixation under nil‐nitrate sand culture in a lathehouse during the summer months. Largest variability for indices at N2‐fixation was among plants within cultivars and not among cultivars. The results indicated that all of the cultivars evaluated would be equally desirable as source material to improve N2‐fixation potential in alfalfa. No effects were noted which could be attributed to fall dormancy, age of the cultivar, or germplasm source.