bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of R‐nj Aleurone Color to Improve Grain Yields of Early Maize1
Authors: Cross H. Z. 
Published: July 2010

Effectiveness of a mass selection technique utilizing variable R‐nj aleurone color expression to select for a correlated yield response in maize (Zea mays L.) was evaluated in 10 North Dakota environments. Two cycles of mass selection for high and low color expression for ears pollinated with a common source of R‐nj pollen were compared with randomly selected check populations. Selection for high R‐nj color expression increased observed yields 0.3 q/ha/cycle and reduced ear moisture at harvest 1.6%/cycle. True gains were estimated to be 2.8 q/ha for yield and − 1.2% for ear moisture. Yield increase was due to an increase in kernels/row. Shelling percentage also was increased.Low R‐nj color selections had a similar trend toward higher yields, but specific yield instability estimated by deviations from regression was increased as compared to random selection. The low color expression populations had greater ability to respond to high yield environments than the high color expression populations.Direct evidence on the effects of color selection on duration and rate of grain fill was not obtained, therefore, the hypothesis that selection for high R‐nj color expression parallels increased grain‐fill rate and/or duration could not be tested. This selection method appears promising for maize improvement and should be subjected to more research to determine why yield differences were associated with aleurone color expressions.
Allelopathy in a Grass‐Legume Association: I. Effects of Hemarthria altissima (Poir.) Stapf. and Hubb. Root Residues on the Growth of Desmodium intortum (Mill.) Urb. and Hemarthria altissima in a Tropical Soil.1
Authors: Young C. C. , Bartholomew D. P. 
Published: July 2010

In Hawaii, Desmodium intortum (Mill.) Urb. ‘Greenleaf’ could not be established in a pasture of the tetraploid Hemarthria altissima (Poir.) Stapf. and Hubb. ‘Bigalta,’ while good survival of ‘Greenleaf’ seedlings was obtained in a sward of the diploid H. altissima ‘Greenalta.’ To help characterize the association further, Greenleaf seeds were planted alone and in mixtures with cuttings of Bigalta or Greenalta in pots with soil containing root residues of Greenleaf and the two grasses. The effects of these residues on the growth and mineral nutrient content of the three species were measured.Growth of Greenleaf was very poor in soil containing root residue of Bigalta. Plant fresh weights were only about one‐fourth of those obtained in the presence of Greenleaf and Greenalta residues. Levels of N, K, Mg, and Ca in the tops of Greenleaf were unaffected by residue source. However, the level of P in Greenleaf tops grown in Bigalta residue was 0.15% on a dry weight basis compared to 0.20% or greater for plants grown in the other two residues. The inhibition of Greenleaf growth in soil in which Bigalta had been grown previously was likely due to allelopathic substances in the Bigalta root residues rather than to competition for environmental factors.
Moisture Migration into Soybean Pods1
Authors: Yaklich R. W. , Cregan P. B. 
Published: July 2010

An evaluation of moisture absorption by soybean [Glycine max (L.) Merr.] pods was conducted in 1978 and 1979. Forty‐six cultivars representing Maturity Groups II through VI were grown to harvest maturity in the field. Representative plants from each cultivar were taken to the laboratory and intact pods were removed from each plant. In each year, two sets of 20 pods from each cultivar were submerged in water for 0, 1, 6, and 24 hours to allow moisture uptake by the pod and seed.Pods and seeds from cultivars in Maturity Groups II through IV absorbed significantly more moisture than those from Maturity Groups V and VI. Pods of ‘Williams’ and ‘Celest’ absorbed the least amount of moisture in Maturity Groups III and V, with both having absorbed approximately 78.0 g H2O/100 g dry wt at 24 hours. Water uptake in these two cultivars were significantly different from the cultivars that absorbed the most water within their respective maturity groups. Seed of ‘Perry’ and ‘Ware’ absorbed the least moisture of the 16 cultivars in Maturity Group IV.
Field Evaluations of Morphactins and Other Growth Regulators for Senescence Delay of Flax, Soybean, Wheat, and Oats1
Authors: Dybing C. Dean , Lay Charles 
Published: July 2010

Field trials were conducted from 1975 through 1979 to detect chemicals which would delay senescence of flax (Linum usitatissimum L.), soybean [Glycine max (L.) Merrill], wheat [Triticum aestivum (L.) em Thell], and oats (Avena sativa L.). Of 18 regulators tested 2 or more years on flax, 11 delayed leaf yellowing after single applications in at least I year. The morphactin chlorflurenol (methyl 2‐chloro‐9‐hydroxyfluorene‐9‐carboxylate), applied postbloom at rates of 25 to 50 g/ha retarded losses of chlorophyll and leaf area and promoted shoot growth and flowering. Early‐flowering cultivars were more responsive than late cultivars. Dichlorflurenol (methyl 9,7‐dichloro‐9‐hydroxyfluorene‐9‐carboxylate) and n‐butyl flurenol (n‐butyl 9‐hydroxyfluorene‐9‐carboxylate), were slightly less and markedly less effective than chlorflurenol, respectively. Other regulators which were effective when applied postbloom were 3‐CPA (2‐(3‐chlorophenoxy)propionamide), TIBA (2,3,5‐triiodobenzoic acid), ethephon (2‐chloroethyl)phosphonic acid), SD‐8339 (N‐ (phenylmethyl)‐9‐(tetrahydro‐2H‐pyran‐2‐yl)‐9‐ H‐purin‐6‐amine), BA + GA4,7(6‐(benzylamino) purlne plus gibberellins 4 and 7), and PP528 (ethyl 5‐(4‐chloro‐phenyl)‐2H‐tetrazole‐2‐acetate). Treatments made earlier than postbloom often resulted in growth abnormalities. Combination of cytokinin or gibberellin with other regulators usually did not enhance effectiveness.Chlorflurenol delayed yellowing of ‘Swift’ soybean when applied in R5 stage at rates of 25 and 50 g/ha. Applications at higher rates or earlier dates caused growth abnormalities. Other effective chemicals included dichlorflurenol, BA, and BA + GA4,7. For oats and wheat, chlorflurenol was ineffective when applied from boot stage to postanthesis at rates up to 1000 and 2000 g/ha, respectively.
Exotic Cottons as Genetic Sources for Drought Resistance1
Authors: Quisenberry J. E. , Jordan W. R. , Roark B. A. , Fryrear D. W. 
Published: July 2010

As irrigation water becomes more limited and energy costs increase on the Southern Great Plains, more cotton (Gossypium hirsutum L.) acreage will be diverted to dryland production. Because water is the most limiting resource for cotton production in this region, production will be positively related to changes which increase the water supply or make more efficient use of water. The purpose of this study was to evaluate plant (shoot) dry matter accumulation in photoperiodic (exotic) cotton strains under irrigated (water optimal) and dryland (water stressed) field conditions, to estimate their water‐use efficiency under dryland, and to determine the relationship between field growth parameters, laboratory evaluations of heat tolerance, and greenhouse estimates of root growth. Fifteen photoperiodic strains and one commerciacl ultivar were planted in irrigated and dryland field tests at Big Spring, Texas and in acrylic tubes in the greenhouse at Temple, Texas. In the Big Spring test, dry weight harvests from both the irrigated and the dryland plots were made at 44, 58, 72, and 86 days after planting (DAP). Soil‐water use was measured with a neutron probe in the dryland plots, and leaf discs were taken from both the irrigated and the dryland tests to measure heat tolerance. In them Temple test, shoot dry weight, leaf area, taproot length, and the number of major root laterals were measured 35 DAP. Analyses of variance and regression analyses were used to evaluate the data.Significant variability was demonstrated among entries for shoot dry weights under both irrigated and dryland conditions, for water‐use efficiency in the dryland test, for heat tolerance at Big Spring, and for root growth at Temple. The number of lateral roots measured in the greenhouse was positively associated with shoot dry weights in the dryland plots, but not in the irrigated plots. Root morphology and root growth potentials appear to be important traits in the adaptation of cotton to conditions where limited soil‐water availability is a major constraint on plant growth.
Vernalization and Photoperiod Requirements for Maximum Flowering of Cicer Milkvetch1
Authors: Townsend C. E. 
Published: July 2010

Cicer milkvetch (Astragalus cicer L.) does not flower in artificial environments that are used to induce flowering of the more commonly grown forage legumes. Therefore, the objectives of this study were to determine the vernalization and photoperiodic requirements of cicer milkvetch and to develop a practical chilling treatment for subsequent flowering in a greenhouse environment. When field grown plants of the cultivar ‘Lutana’ were brought to the greenhouse every 2 weeks from mid‐September through December, percent of plants flowering increased linearly from 29 to 100. Removal of top growth in mid‐September reduced subsequent flowering from 75 to 33%. Flowering after vernalization at 5 C night/20 C day (5/20 C) the laboratory was better than after vernalization in the field except for the late November and early December sampling dates. Percentge of plants flowering (95 to 100%) and profuseness of flowering (12 to racemes/plant) were similar [or the 5/20 C laboratory treatment and the late field sampling dates. The 5/20 C treatments were 6 weeks in duration with a total of 364 hours at 5 C.Considerable variability exists among vernalized plants of the cultivar Lutana for photoperiodic response to flowering. Although only 30% of the plants flowered at the 13‐hour photoperiod, a few plants flowered profusely. The highest percentage of plants flowering (98%) and the most profuse flowering (13.3 racemes/plant) occurred at photoperiods of 15 and 16 hours.
Digestibility of Kleingrass Forage Grown Under Moisture Stress1
Authors: Pitman W. D. , Victor D. M. , Holt E. C. 
Published: July 2010

Low forage digestibility of warm‐season perennial grasses frequently limits performance of grazing animals. Digestible energy intake is of particular concern during hot, dry periods of mid‐summer. Although relationships between plant characteristics affecting digestibility and temperature, irradiance, and soil fertility have been reported, the relationship between forage digestibility and moisture stress has yet to be clearly determined. The purpose of this study was to determine the influence of moisture limitations on digestibility of kleingrass (Panicum coloratura L.) forage.Kleingrass plants cloned from a single parent were grown in pots under greenhouse conditions at five watering levels. Soil moisture ranged among watering levels from field capacity down to near the permanent wilting point. Four pots or replications for each of five watering levels were arranged in a randomized block design. Plants were harvested on four successive harvest dates after a 15‐day period of regrowth. In vitro digestible organic matter (IVDOM) of leaves and stems, gravimetric soil moisture, plant water status (leaf xylem pressure potential), forage yield, and plant leafiness were determined at each harvest date. Although percent soil moisture and leaf xylem pressure potential declined as a result of successively lower watering levels, yields per pot and IVDOM of both leaves and stems were not significantly reduced until reduced watering lowered soil moisture to 9.1% and leaf pressure potential to −7 bars. Only leaf growth occurred when soil moisture and leaf xylem pressure potential were reduced to 7% and −14 bars, respectively. Leaf and stem IVDOM ranged from 63.8% and 60.8% with non‐stressed material down to 33.6% and 42.8% at the most stressed level producing leaf or stem growth, respectively. The results indicate that low forage digestibility of warm‐season grasses in midsummer may be associated with moisture limitations.
Selection Procedures for Developing Fertility Restorer Lines in Wheat1
Authors: Ghiasi H. , Lucken K. A. , Hammond J. J. 
Published: July 2010

The effectiveness of selection for anther extrusion in fertility restorer lines of wheat (Triticum aestivum L. em Thell.) to improve cross‐pollination potential and the relationship between the self‐fertility of the restorer lines and the fertility of their testcrosses were examined in six R/B (restorer/conventional line) crosses and one R/R (restorer/restorer) cross. A common restorer parent, R109, was used in all crosses. One hundred and fifty‐two F6 R‐lines, selected from 722 F5 lines, were evaluated in yield trials at three locations in North Dakota in 1979. All F6 lines were testcrossed to male steriles with Triticum timopheevi Zhuk. cytoplasm, and fertility of testcross progeny was used as the criterion for fertility restoration potential. The effect of restorer genes on several agronomic and quality traits also was investigated.Regressions of the F6 on F5 generations indicated that selection for anther extrusion in the F5 was effective although somewhat less effective than selection for heading date and plant height. Forty percent of the variation in the F6 for anther extrusion was determined by variation in the F5 compared to 64 % for heading date and 72 % for plant height. R‐line anther extrusion was only slightly indicative of fertility restoration potential; the R2 for testcross F1 seed set vs. F6 R‐llne anther extrusion was 10%.Among the 152 R‐lines, there was a low negative association between anther extrusion and 200‐kernel weight and a low positive association between R‐line test weight and testcross seed set, When lines were grouped by testcross fertility, no differences among testcross fertile, testcross partially fertile, and testcross male‐sterile lines were found for any trait except R‐line anther extrusion and testcross anther extrusion. The R109‐derived restorer genes and their associated linkage blocks had no deleterious effects on agronomic traits.
Abscisic Acid and Abscission of Young Cotton Bolls in Relation to Water Availability and Boll Load1
Authors: Guinn Gene 
Published: July 2010

A field experiment was conducted to determine whether two factors, water deficit and fruit load, that are known to affect fruit abscission might also affect the concentrations of ABA in young cotton (Gossypium hirsuturm L. ‘Deltapine 70’) bolls. The effects of water deficit were estimated by comparing ABA concentrations and abscission rates of boils in control and stressed plots, and by following changes during irrigation cycles. The effects of fruit load were determined by removing about 4/7 of the flowers in partially defruited plots, and by comparing changes as boll load increased during the season.Both ABA concentration and abscission rate of bolls increased with water deficit and decreased with relief of stress by irrigation. Boll abscission rates increased as boll load increased, and were lower in the partially defrulted than in the fruited plots. Bolls in the partially dcfruited plots contained less ABA on some, but not all, harvest dates. Watei: deficit apparently had a greater effect than boll load on the ABA content of young bolls.The results indicate that water deficit increases the ABA content of cotton bolls, and they provide additional circumstantial evidence that ABA is one regulator of young boll abscission in cotton. However, differences in ABA content did not account for increased boll abscission rate with increasing boll load during the season nor for differences in abscission between fruited and partially defruited plants.
Sampling for Eggs, Larvae, and Adults of the Bluegrass Billbug1,2
Authors: Kindler S. D. , Kinbacher E. J. 
Published: July 2010

A test was conducted to determine the precision of a pyrethrlns drench applied to the surface of Kentucky bluegrass, Poa pratenis (L.), to estimate the densities of soil and thatch inhabiting adult and root‐feeding larvae of the bluegrass billbug, Spenophorus parvulus Gyllenhal. Eighty‐seven percent of the adults were recovered from in situ sod with a 0.45 cm thick thatch while 82% of the adults were recovered from in situ sod with a 1.15 cm thick thatch. Root‐feeding larvae did not respond to the pyrethrins drench.In tests comparing a food blender extraction method with a hand dissection, method of extracting eggs and young larvae from infested plants, the number of eggs and larvae recovered from the blender extraction method did not differ significantly from the number of eggs and larvae recovered by hand dissecting the plant material.
Response to Selection for Low Temperature Sprouting Ability in Tomato Populations1
Authors: De Vos D. A. , Hill R. R. , Hepler R. W. 
Published: July 2010

Selection for low temperature sprouting ability was conducted in field and laboratory environments in parental and F2 families derived from a six‐parent dial lei of tomatoes (Lycopersicon esculentum Mill.). Two cold tolerant (CT) and four non‐cold tolerant (NCT) parents were examined. Variation among parental and F3 progeny selections was partitioned into average effects and into linear and quadratic responses to selection. The results of the selection experiment were compared with expectations based on a previous experiment which involved the parents and F1 hybrids.Variation among parents for average effects was highly significant, but no response to selection was observed in families derived from the parents. Average response to selection in the field was significant for families derived from CT ✕ NCT crosses, and there was significant variation among families in this group for the magnitude of response to selection. A response to selection in the field was not observed in families derived from CT ✕ CT or from NCT ✕ NCT crosses. Average response and variability among families for response to selection in the laboratory was significant for each of the family groups, but the greatest response was observed in families derived from CT ✕ NCT crosses.Observed responses to selection did not always agree with expectations based on diallel analysis of the parents and F1 hybrids. Some families for which the F1 analysis indicated a great degree of genetic diversity showed almost no response to selection.
Advanced Generation Analysis of Days to Heading in Three Winter Wheat Crosses1
Authors: Avey D. P. , Ohm H. W. , Patterson F. L. , Nyquist W. E. 
Published: July 2010

Three hierarchal populations in the F6 generation were used to estimate the importance of additive, additive‐by‐additive, and dominance genetic variances for heading date in three winter wheat (Triticum aestivum L. em. Thell) populations. The populations were progenies from three single crosses between the cultivars ‘Aobakomugi’, ‘Doublecrop’, and the Purdue Univ. line, P6879. Under Indiana conditions, Aobakomugi heads about 5 and 14 days earlier than Doublecrop and P6879, respectively.Two random F3 plants were grown from each of 291 random F2 plants from the three crosses. Two random F4 plants were grown from each of the F3 plants. Twenty random F5 plants from each of the 1164 F4 plants were grown in a row 1 m long. F6 seed from plants within each row was bulked to give rise to the 1164 F6 lines.F6 lines, the three parents, and two cultivars, ‘Monon’ and ‘Beau,’' were grown in a randomized complete block design in experiments at Lafayette and Sullivan. Ind. in 1980 and analyzed as a nested effects model.Additive variance was significant for heading date in the cross Aobakomugi/Doublecrop; additive and dominance variances were significant in the cross Aobakomugi/P6879; and additive × additive effects were significant in the cross Doublecrop/P6879. A duplicate dominant genetic system is proposed to account for part of the genetic variance in populations from crosses with P6879. The appropriateness of early and advanced generation selection for heading date is briefly discussed.
Soybean Mosaic Virus Investigations with Susceptible and Resistant Soybeans1
Authors: Hartwig E. E. , Keeling B. L. 
Published: July 2010

The soybean mosaic virus (SMV) susceptible soybean [Glycine max (L.) Merr.] breeding line D60‐9647 was inoculated with SMV‐1 at five different stages of development in each of 4 years to observe the effects of SMV in an area where vector dissemination of SMV is not apparent. Mean reduction in seed yield over the 4‐year period was 12%. Time of inoculation made little difference. There was a large increase in percent mottled seed following SMV inoculation with the highest percentage resulting from inoculation at the V7 stage of development. Percent of seedlings showing virus symptoms (15%) was highest from the inoculation at the V7 stage. Percentage of seed germination was reduced from 95 to 88%.Another study was conducted in which closely related SMV resistant and susceptible lines were compared using seed harvested from susceptible lines which had been inoculated with SMV. Seed yield of the susceptible lines, not again inoculated, did not differ from that of the resistant lines. Seed yield of SMV‐susceptible lines inoculated with SMV‐1 averaged 8% lower in seed yield than resistant lines in 1974 and 12% lower in 1975. The results indicate that under conditions similar to those in which our studies were conducted, seed from SMV infected plants can be utilized for planting with no undesirable effects.
Variation in Leaflet Orientation among Soybean Cultivars1
Authors: Wofford T. J. , Allen F. L. 
Published: July 2010

The degree of leaflet orientation was measured for five soybean (Glycine max L., Merr.) cultivars on an hourly basis from 0620 (0700 EST) until 1820 (1900 EST) hours Local Solar Time during the 10 node stage of development (V10) and from 0520 (0700 EDT) until 1820 (2000 EDT) hours during the beginning pod stage (R3). Measurements were taken on 4 separate days during each growth stage. Our primary objective was to determine if differences exist among soybean cultivars in degree of leaflet orientation.There was significant variation among cultivars in the degree of orientation of the center and the side leaflets of trifoliolates at different times of the day.during both growth stages. The orientation of the center leaflets of a trifoliolate differed from that of the side leaflets. The vertical inclination of the center leaflets tended to change over time while the horizontal inclination remained relatively constant. On the other hand, the horizontal inclination of the side leaflets tended to change over time while their vertical orientation remained relatively constant. However, due to their location relative to each other, the different directions of movement of the center vs. side leaflets seem necessary in order for all three leaflets to attain similar exposures to incoming radiation.Maximum variation in leaf movement was noted from 0820 until 1620 hours during both V10 and R3 stages of development. Higher angles of inclination were obtained and maintained during R3 than V10.The K concentration in pulvini was significantly higher (p < 0.01) during the tense state (higher angles of leaflet orientation) than during the relaxed state. It appears that the K concentration in the pulvinus might have some role in regulating the bending and straightening movements of the pulvini, perhaps by inducing changes in turgor pressure.