bluuebunny/crossref_metadata_2025_split huggingface dataset:
Implications of Genotype ✕ Planting Date and Row Spacing Interactions in Double‐cropped Soybean Cultivar Development1
Authors: Carter T. E. , Boerma H. R. 
Published: July 2010

Soybeans (Glycine max (L.) Merr.) are grown in the southeastern U.S. as both a full‐season crop and a double crop. The cultivars currently grown in the doublecropped environment were developed and released based on performance in full‐season environments. To determine the need of a breeding program for double‐cropped cultivars, 10 genotypes were evaluated at two row spacings (48 and 96 cm) in an early (21 May and 3 June) and late (28 June and 30 June) planting date in 1975 and 1976.The genotype ✕ planting date interaction was significant for seed yield, lodging, flowering date, and height at flowering and maturity over years. For seed yield, this interaction resulted hi changes in rankings of genotypes and differences in the results of the L.S.D. means test. The genotype ✕ row spacing interaction was significant for seed yield, seed size, and number of pods/ms over years. The interaction for seed yield was large enough to cause changes in rankings of genotypes and differences in the results of L.S.D. means test. The genotype ✕ planting date ✕ row spacings interaction was significant for seed yield. Comparison of the yield of the 10 genotypes in the early‐wide and late‐narrow environments, the common planting date‐row spacing combination for full season and double‐cropped soybeans, respectively, indicated that the two highest yielding genotypes hi the early‐wide environment ranked ninth and 10th in the late‐narrow environment. The correlation for yield or rank order based on yield of the genotypes between the two environments were negative, but nonsignificant.The relationships between yield and various plant traits were different in the various planting date‐row spacing environments. A later flowering date, more seeds/pod, longer internodes, and shorter reproductive period were associated with increased yield in the late‐narrow but not the early‐wide environments. Since double‐cropped soybeans are usually planted in late June in narrow rows, the magnitude of the interactions among genotypes, planting date, and row spacing for yield and the different relationships between plant traits and yield in the fullseason and double‐cropped environments would indicate that development and testing of double‐cropped cultivars should be practiced in a late‐planted, narrow‐row environment for maximum progress.
Genetic Variability Among Glandless Cottons for Resistance to Two Insects1
Authors: Meredith W. R. , Hanny B. W. , Bailey J. C. 
Published: July 2010

The objective of this study was to determine if genetic resistance to tarnished plant bug (Lygus lineolaris Palisot de Beauvois) and tobacco budworm (Heliothis virescens F.) could be detected among glandless strains of cotton (Gossypium hirsutum L.). We grew 97 glandless strains in the field in two environments. In the first environment, tarnished plant bugs were controlled by five weekly sprayings of an insecticide. In the other environment, tarnished plant bugs were attracted and increased by growing mustard (Brassica juncea (L.) Czern. & Coss), nearby rows. A significant strain ✕ environment interaction for lint yield indicated that there was genetic variability among the glandless strains for resistance to tarnished plant bug. Inspection of the least sensitive strains indicated that many possessed some combination of nectarilessness, hirsuteness, or rapid fruiting ability. These traits and characteristics had been previously found to result in less susceptibility to tarnished plant bugs.First instar tobacco budworm larvae were established on young plants of 99 glandless strains when the third true leaf was expanding. Significant variability was detected for 7‐day average larval weight. Inspection of the 14 strains supporting these smallest larva revealed no readily observable morphological trait that might confer resistance. A second test with the 14 selected strains indicated that the ability of the larvae to develop on these strains was generally lower than on glandless ‘Stoneville 7A’. While four strains did not differ significantly from glanded Stoneville 7A, none of the resistant glandless strains equalled glanded Stoneville 7A in suppressing larval weight. Most of the resistant glandless strains came from one cross of the Louisiana breeding program at Bossier City.These results indicate that significant useful variability for decreased susceptibility to both tarnished plant bug and tobacco budworm is present in glandless cottons.
Effects of Mineral Elements on Hydrocyanic Acid Potential in Sorghum Seedlings1
Authors: Clark R. B. , Gorz H. J. , Haskins F. A. 
Published: July 2010

Sorghum [Sorghum bicolor (L.) Moench ‘Early Hegari’] seedlings were grown in nutrient solutions with various combinations of chlorides, nitrates, sulfates, and phosphates (dihydrogen) of ammonium, potassium, calcium, and magnesium to determine the effects of the mineral elements on hydrocyanic acid potential (HCN‐p) in leaves.Growth was maximum or near maximum for the shoots of sorghum seedlings at 1 to 30 meq salt in solution and for the roots at 0.3 to 3 meq. The duration of exposure of seedlings to the treatment solution required for significant changes in HCN‐p was at least 2 days. The effects of various concentrations of individual salts on HCN‐p were: KCl, a slight decrease; K2SO4, KH2PO4, NH4Cl, NH4NO3, (NH4)2SO4, NH4H2PO4, and Ca(H2PO4)2, an increase; and KNO3, CaCl2, Ca(NO3)2, CaSO4, MgCl2, Mg(NO3)2, and MgSO4, no significant effect.When potassium and ammonium salts of a common anion were added in 3 × 3 factorial experiments, increasing levels of ammonium salts at the 1X potassium level generally increased HCN‐p, but varied effects of higher levels of potassium salts were observed. In factorial experiments, different levels of pairs of potassium salts of the various anion had no significant effect on HCN‐p. In experiments with pairs of ammonium salts, increases in salt concentration generally increased HCN‐p.It was concluded that large changes in salt concentration affected alterations in HCN‐p were associated with changes in ammonium salt levels.
Cyanogenesis in Indiangrass Seedlings1
Authors: Haskins F. A. , Gorz H. J. , Vogel K. P. 
Published: July 2010

In a study of seedlings of 72 entries representing 39 species, 14 genera, and 2 tribes of grasses, only entries of the genus Sorghastrum were found to contain the cyanogenic glucoside, dhurrin [(S)‐p‐hydroxymandelonitrile β‐D‐glucopyranoside], Dhurrin was found in seedlings of each of the 10 entries of indiangrass [Sorghastrum nutans (L.) Nash] and the three entries of S. pellitum.Seedlings of five indiangrass cultivars were assayed for dhurrin concentration. Levels expressed as HCN potential (HCN‐p) ranged from about 900 ppm for ‘Holt’ to about 1,200 ppm for ‘Llano’ and ‘Oto’.Further studies with Oto seedlings indicated that first leaves were higher and more uniform in HCN‐p than were other portions of the shoot, but all shoot portions contained dhurrin. Seedling roots also contained dhurrin, but the HCN‐p of roots was appreciably lower than that of shoots.Spectral evidence indicated that dhurrin was present in extracts of leaves of tillers harvested from field‐grown plants. Dhurrin was not detected in all such tillers, however. Indiangrass tiller extracts contained more interfering substances than seedling extracts, in agreement with previous observations on Sorghum seedlings.
Selection for Cold Germination in Two Corn Populations1
Authors: McConnell R. L. , Gardner C. O. 
Published: July 2010

Tolerance of corn (Zea mays L.) to low temperature conditions after planting requires rapid germination, vigorous seedling growth, and resistance to disease and insect pests. A selection scheme designed to improve cold tolerance in breeding material was initiated in two breeding populations, Iowa Stiff Stalk Synthetic (SSCG) and Pioneer Cold Tolerant Synthetic (CTCG). Laboratory and field selection were employed in the procedure. Seedlings developed from the first seeds to germinate at 7.2 C in the laboratory (20% selected) were transplanted to the field, selected for agronomic traits, and self‐pollinated. The selfed progenies were recombined in winter nurseries to initiate the next cycle of selection in the laboratory.Regression analyses of the four cycles of selection indicated that cold germination under laboratory conditions (7.2 C) improved 8.8 and 9.9% per cycle in CTCG and SSCG, respectively. In the field, however, little improvement was observed in emergence or seedling vigor. The lack of correlation between laboratory and field results for these cold‐tolerant traits was attributed to mild spring weather during the 2 years of evaluation. Selection for germination at cold temperatures did not have any detrimental effects on other agronomic traits measured in the populations.
Imbibitional Chilling Sensitivity Among Soybean Cultivars1
Authors: Bramlage W. J. , Leopold A. C. , Specht J. E. 
Published: July 2010

Fifteen soybean (Glycine max (L.) Merr.) cultivars were screened for sensitivity of embryos to imbitional chilling injury. All were susceptible to injury, but sensitivity varied greatly. Some showed no injury at 7 C while others were injured at 17 C. Embryos of earlier maturing cultivars tended to be more susceptible to imbibitional chilling injury than those of later maturing cultivars. This relationship of time of maturation to chilling sensitivity was confirmed using near‐isogenlc lines of ‘Clark’ soybean, a cultivar possessing various genes that advanced or delayed maturity. Earlier maturing lines were more sensitive to chilling than later maturing lines. Leakage of solutes during imbibition, measured as OD280, was negatively correlated with germination when near.isogenic strains were compared, but was not closely correlated when different cultivars were compared.It is proposed that seed maturation occurring later in the growing season, during periods of relatively low temperature, hardens seeds against chilling injury.
Environmental and Genetic Influences on Alfalfa Nectar1
Authors: Teuber L. R. , Barnes D. K. 
Published: July 2010

Alfalfa (Medicago sativa L.) is a major source of nectar for honey production in the USA, but no attempts have been made to improve its nectar production potential. The objectives of this research were to provide basic information on several environmental and genetic factors to establish recommended sampling and selection procedures for a nectar breeding program.Two high, two intermediate, and two low nectar‐producing clones from each of two unrelated sources (‘Vernal’ and ‘Team’) were used to study the effect of soil moisture, raceme age, and raceme position on nectar volume and percentage solids. Twenty‐eight clones from Vernal were used to compare measurements of nectar volume and percentage solids on plants grown in the field and greenhouse. Inheritance studies of nectar volume were conducted on diallel crosses made among six parents in each of two populations. Design II crosses were made between populations. Pxogenies from all crosses were grown in the greenhouse.Soil moisture did not significantly affect either nectar volume or percentage solids in the nectar. Raceme age significantly affected nectar volume but not percentage solids in the nectar. Racemes with newly opened terminal florets had less nectar than either intermediate age racemes or older racemes on which some basal florets were beginning to wilt. Raceme position on the stem did not affect either nectar volume or percentage solids in the nectar. The correlation between field and the average of three greenhouse measurements of nectar volume was significant (r = 0.49, 26 dr). Nectar volume plants selected based on two greenhouse sampling dates (May‐October) was 125% of the nectar volume of the population grown in the field. Results of the inheritance study indicated there were no reciprocal differences for nectar volume and that inheritance of nectar volume was predominantly additive. A recommended list of sampling procedures was developed for nectar breeding.
Temperature and Drought Effects on Blast and Other Characteristics in Developing Oats1
Authors: Chinnici Madeline F. , Peterson David M. 
Published: July 2010

Increased blast and reduced kernel yield have been observed in oat (Arena sativa L.) when periods of environmental stress occur during the growing season. The objective of this experiment was to determine the differential effects of controlled temperature and drought stress at specific times during panicle development on percent blast (blasted spikelets/total spikelets ✕ 100), total spikdets/panicle, plant height, and several kernel characteristics.‘Froker,’ a late season cultivar, and ‘Clintland 64’ and ‘Wright,’ midseason cultivars, were grown in pots in a mixture containing equal parts of peat and vermiculite. The pots were irrigated with half‐strength Hoagland's solution, and placed in an environmental room programmed for the natural photoperiod and daily normal temperatures and relative humidity for 23 April to 15 August at Madison, Wis. Plants were subjected to heat, cold, and drought treatments at four times during panicle development: 26, 40, 53 and 63 days after planting, stages 1 to 4 respetively.Typical environmental stresses that occur during the growing season of oats were found to increase blast and decrease yield and kernels/panicle. Blasting in Froker was increased by temperature and/or drought at all stages, in Wright by drought at stage 1 and temperature at stages 2 and 3, but in Clintland 64 only by drought at stage 4. Total spikelets/panicle were reduced by drought and heat at stages 2 and 3 (mean of all cultivats). These effects resulted in fewer kernels/panicle and reduced yield. The most severe yield reductions occurred as a result of drought at stage 2 and 4, and heat at stage 3. Compensation for increased blasting by formation of heavier kernels did not occur. Drought at stage 4 reduced kernels/fertile spikelet to near 1.0. In general, plant height was reduced by the same treatments causing yield reductions. Kernel protein concentration was mostly unaffected, except for an increase in kernels from plants that were drought stressed at stage 4.These results emphasize the value of early planting to avoid the potential damage of heat and drought. Cold treatments had the least effect on yield. The data suggest cultivar variability in stress tolerance. Stress‐tolerant cultivars could possibly be developed by selection and breeding, if suitable screening procedures could be established.
Effect of Planting Dates and Soybean Cultivars on Pod Damage by Corn Earworm1
Authors: Joshi J. M. 
Published: July 2010

Eight soybean [Glycine max (L.) Merr.] cultivars during 1974 and 16 cultivars during 1975 and 1976 were planted on five different planting dates with 14‐day intervals between each planting to determine which soybean cultivars may escape corn earworm (Heliothis zea Boddie) damage. Soybeans planted by or after mid‐June generally were more susceptible to corn earworm than the earlier plantings. Each successive delay in planting resulted in more pod damage.The cultivar ‘Delmar’ was highly susceptible, whereas ‘Wye’ exhibited minimum pod damage. The corn earworm showed a high level of non‐preference towards Wye. Corn earworm infestations increased with each successive delay in planting. Maximum infestation was observed on soybeans planted in July. Strain ED 73.371 had the highest amount of active infestation, yet pod damage was very low. This indicates some other mechanism of resistance, such as antibiosis. Proper choice of soybean cultivar according to the desired planting date can help in minimizing pod damage from corn earworm.
Gibberellin Studies with Sugarcane. III. Effects of Rate and Frequency of Gibberellic Acid Applications on Stalk Length and Fresh Weight1
Authors: Moore Paul H. , Ginoza Harold 
Published: July 2010

Sugarcane (Saccharum spp. hybrids) stalk length, fresh weight, dry weight, and sucrose content, normally reduced when plants are grown under reduced sunlight (250 Langleys/day) and cool temperatures (mean daily temperature 23 C), can be increased with foliar applications of gibberellic acid (GA3). Maximum increases in lengths and fresh weights of seven Hawaiian commercial cultivars were a function of cultivar treated, the amount of GA3 applied, the number of applications, and the interval between applications.Lowland cultivars produced the largest gains in response to the largest quantities of GA3; highland cultivars produced smaller gains. The effects of two applications of 1.0 mg GA3 per stalk depended on the interval between applications. Least growth gains occurred when the intervals were 0 and 45 days; greatest growth gains occurred when the interval between applications was 15 days. The effect of a 30‐day interval was nearly equal to the 15‐day interval, but the 30‐day interval did not result in as great a loss of stalks as occurred at the 15‐day interval. Three and four applications of 0.5 mg GA3 per stalk at 15‐day intervals were less effective in increasing stalk length and fresh weight than were three and four applications of 0.5 mg GA3 per stalk at 30‐day intervals. Greatest gains in fresh weight in response to 2.0 mg GA3 per stalk were in response to the greatest number of applications, four, if they were at 30‐day intervals.
Male‐Fertility Restoration in Crosses of R5 with Soft Red Winter Wheats1
Authors: Wickersham Dale S. , Patterson F. L. 
Published: July 2010

The inheritance of male‐fertility restoration was studied in crosses of the spring wheat restorer germplasm line R5 with cms ‘Monon’ and cms ‘Redcoat’ soft red winter wheat (Triticum aestivum L.) cultivars with T. timopheevii Zhuk. cytoplasm. Two greenhouse cycles of Fl's, F2's, BC1's, along with the restored parent, and malesterile parents, were grown to provide two sets of data. Genetic hypotheses were postulated as expected ratios of fertile: semi‐sterile: sterile plants and data were tested for goodness of fit by chi‐square analyses. The BC1F2 populations and F3 populations were grown in the field to determine the proportion of families segregating for sterility. Results from the cms Monon/R5 crosses indicated the presence of two partially dominant complimentary restorer factors in the greenhouse and field environments. Complete fertility restoration was expressed only when both dominant factors were present to either the homozygous or heterozygous condition. Results from the cms Redcoat/R5 crosses suggested the presence of three dominant factors in the greenhouse environment, but segregation in the field environment suggested that only two factors were involved.The complete restoration of fertility of F1 plants in the environments tested suggests that R5 is a valuable source of restorer factors for developing R‐lines for hybrid soft red winter wheats.
Seasonal Variation in the Performance of Soybeans in Hawaii1
Authors: Beard Benjamin H. , Gilbert James C. , Sekioka Terry 
Published: July 2010

Our objectives were to determine the variation in yield and other characteristics of soybeans (Glycine max (L.) Merr.) grown in Hawaii. We were especially interested in finding the best adapted cultlvars for planting during the winter months to use as parental germplasm for cultivar improvement.Soybean cultivars were grown at three locations in Hawaii in each month of the year, except July and December. Higher than average yields were obtained when soybeans were planted in March, April, May, or June, while lower than average yields were obtained if planted in other months.Significant differences in soybean yields were associated with years, locations, dates of planting, and cultivars. Cultivar ✕ date, and cultivar ✕ location interactions were significant in some analyses, but nonsignificant in others. ‘Davis’ had the highest mean yield at each location.
Interrelationships among Wheat Genes for Resistance to Hessian Fly1
Authors: Stebbins Nancy B. , Patterson F. L. , Gallun R. L. 
Published: July 2010

The interrelationships among genes for resistance in six cultlvars and one llne of hexaplold wheat (Triticum aestivum L. aestivum group) of three biotypes of Hessian fly (Mayetiola destructor Say) were analyzed using reactions of F, lines or backcrosses plant progenies at 20 C. Chi‐square goodness‐of‐fit tests were used to test genetic hypotheses. Recombination frequencies and standard errots were determined using the maximum fikelihood method.Three hexaploid wheats, Purdue 4835A4‐6, ‘Knox 62’, and ‘Lathrop’ have resistances to biotypes A and B of Hessian fly derived from PI 94587 tetraploid durum wheat (T. durum L. durum group). The single dominant gene pair H6‐H6, which also confers resistance in Knox 62 and Purdue 4835A4‐6, governs Lathrop's resistance. PurPurdue selection 822‐34 has a single dominant gene pair derived from ‘Elva’ (T. turgidum L. durum group) for resistance to biotype D of Hessian fly. The resistance was found to be inherited independently of the H5H5 gene pair in ‘Abe’. The new gene for resistance was assigned the symbol H9 H9 was linked to H3 (on chromosome 5A) with a recombination frequency of 0.155±0.048. This places H3, H6, and H9 on chromosome 5A but the gene order was not established. The genotypes of ‘Arthur 71’ and Abe were found to be H3H3 H5H5. We established that H5 is independent of the linkage block containing H3, H6, and H9.
Hydrocyanic Acid Potential in Several Sorghum Breeding Lines as Affected by Nitrogen Fertilization and Variable Harvests1
Authors: McBee George G. , Miller F. R. 
Published: July 2010

Many sorghum (Sorghum bicolor (L.) Moench) breeding lines have not been evaluated for inherent potential hydrocyanic acid (HCN‐p) levels under field conditions. Additionally, levels of HCN‐p remaining in sorghum stover used for animal grazing after grain harvest needs elucidation as well as N effects on lines shown to be inherently low in HCN‐p.Fifteen entries, including 13 sorghum lines, one sweet sorghum, and one sudangrass (Sorghum sudanense (Piper) Stapf), were evaluated for differences in HCN‐p, influence of N fertilization, and date of harvest. The entry Tx7000 was consistently low in HCN‐p at all harvest dates and only exceeded the “threshold of danger” (200 ppm) at the preboot stage. This level is considered to be an approximate value at which HCN may become toxic to ruminant animals. The highest ranking entry was SC0599‐6, a Rio selection, which exceeded the 200 ppm level at all stages of harvest employed. Even in entries inherently low, added N increased HCN‐p, which supports the theory that caution must be exercised when growing cultivars reportedly low in HCN‐p, especially when N fertilizer is applied.As expected, HCN‐p tended to decrease with plant maturity. After physiological maturity of the grain, panicles were removed and leaf blades sampled 8 days later. Two of the entries still retained HCN‐p in excess of 200 ppm, indicating a need to exercise caution with some cultivars when allowing cattle to graze stover after grain harvest.