bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Bagging Sweet Sorghum Panicles on Stalk Yield and Juice Quality1
Authors: Broadhead Dempsey M.
Published: July 2010

Panicles of sweet sorghum plants (Sorghum bicolor (L.) Moench) are bagged to insure self‐pollination and seed preservation. The top two leaf blades are removed just before applying the bag to facilitate bagging. Plants with bagged and unbagged panicles with the top two leaf blades attached or removed were compared. These comparisons were made with ‘Brandes’, ‘Dale’, and ‘Rio’ in 1974, 1975, 1976, and 1977 to determine the influence of panicle bagging on stalk yield, juice Brix, sucrose, and purity. Bagging the panicle or removing the top two leaf blades of unbagged sweet sorghum plants significantly reduced the juice Brix, sucrose, and purity compared with normal plants. Removing the top two leaf blades and then bagging the panicle gave an even greater reduction in juice Brix, sucrose, and purity than either bagging the panicle or removing the top two leaf blades alone. Bagging the panicle with the top two leaves did not reduce gross stalk yield. However, removing the top two leaf blades of either bagged or unbagged plants gave a slight reduction in gross stalk yield. Stripped stalk yield was not affected by the treatments.
Growth Type and Yield Comparisons of Forage Species after Seed Multiplication in Germany and in the United States. II. Meadow Fescue, Timothy, and Perennial Ryegrass1
Authors: Simon Uwe , Kastenbauer A.
Published: July 2010

Seedlots of meadow rescue (Festuca pratensis Huds.), timothy (Phleum pratense L.), and perennial ryegrass (Lolium perennial L.) were increased for two to four consecutive generations at one location in Germany and three locations in the United States. The population structure and forage yields of the original seed and advanced generations were investigated at Weihenstephan, Germany.

All meadow rescue progenies were significantly taller and earlier and made better regrowth than the original seed. American lots and the corresponding German populations did not significantly differ in these characters. In timothy, variation of plant characteristics among locations and generations was neglegible. In perennial ryegrass, most progenies were significantly more vigorous in spring, earlier and taller than the original lot. American lots from lower latitudes were taller and earlier. The fourth subsequent generation from the most south. erly location, Shafter, Calif., headed 6 days earlier and grew 11 cm taller than the original lot. Percentage of seedling fluorescence of samples from the United States did not differ from the corresponding German progenies. There was no detrimental effect on dry‐matter forage yield due to seed multiplication in the United States.
A Developmental Analysis of Seed Size in Common Bean1
Authors: Hsu Francis C.
Published: July 2010

A comparative, developmental analysis of seed size was made between two cultivars of common bean (Phaseolus vulgaris L.) with contrasting mature seed sizes. The seed of large‐seeded cultivar ‘Taylor's Horticultural’ is smaller than that of small‐seeded cultivar P.I. 226895 from anthesis to day 20, and this relationship is reversed from day 20 to maturation. This pattern of relative size relationship is manifested by the whole seed and by both major components of the seed (embryo and seed coat). Length, weight, and volume were the parameters measured to determine seed size; measurements of all three were continued throughout development of the seed.
Evaluation of Vigor Tests in Soybean Seeds: Relationship of the Standard Germination Test, Seedling Vigor Classification, Seedling Length, and Tetrazolium Staining to Field Performance1
Authors: Yaklich Robert W. , Kulik Martin M.
Published: July 2010

Laboratory tests for standard germination, seedling vigor classification, seedling length, and tetrazolium staining were performed on 144 and 81 seed lots of soybean [Glycine max (L.) Merr.] in 1975 and 1976, respectively. Results from the laboratory tests were compared with emergence and stand data obtained from these same seed lots on two sites (sandy and heavy soil types) and three dates of planting (early, pre‐optimum, and optimum) each year. Yield was obtained for the heavy soil type, optimum planting date.

Most laboratory test measurements were significantly correlated with field emergence, but r values were <0.8. Overall, the correlations showed a trend that was dependent on soil type but not date of planting. Generally, the laboratory test measurement was correlated with emergence for all planting sites and dates of planting. The corresponding correlations for plant stand and emergence were similar. Correlations of laboratory test measurements with yield were low, r≤0.340 and r≤0.282 in 1975 and 1976, respectively

Laboratory test measurements were used to develop models predicting field emergence. Combinations of three laboratory test measurements in the model gave near maximum R2 values. Four such models were able to predict emergence at five of the six planting date and site combinations each year.
Cell Wall Constituents in Plant Parts of Reed Canarygrass Clones1
Authors: Marum P. , Hovin A. W.
Published: July 2010

Forage dry matter intake potential by ruminants is negatively associated with cell wall constituent concentration (CWC%) above a critical level. Two experiments were conducted to determine the effects of leaf blade, leaf sheath, stem, and maturity on total CWC% (TCWC%) to improve selection procedures in breeding of reed canarygrass (Phalaris arundinacea L.).

Three clones, previously characterized as being high, medium, and low in T‐CWC%, were sampled 11, 29, 33, 44, 55, and 66 days afer growth started in spring. Throughout the sampling period the clone with high T‐CWC% had the largest proportion of stems and the low T‐CWC% clone had the smallest proportion of stems. The CWC% in leaf sheath and stem tissues of all clones increased with age through anthesis. After anthesis, no consistent CWC% change took place due to formation of new shoots from stem nodes. Mean daily increase in CWC% of stems (1.11%) was twice that of blades (0.52%). Selection plants for low forage CWC% anytime up to anthesis would have given smiliar results for all three clones.

Plant parts of 12 clones, which had been selected previously for different concentrations of CWC, were analyzed at anthesis and regrowth stages. At anthesis, the ranges in CWC among clones were 10.5 percentage points in stems and 5.2 points in blades. For 7‐week.old regrowth forage, the ranges were 7.7 percentage points and 7.9 points, respectively. The average CWC% in stems was 19.9 percentage points higher than that in blades at anthesls, and 25.8 percentage points higher in the regrowth forage. Leafy plants had less T‐CWC% than did stemmy plants. Leafy plants also tended to have lower CWC% in all plant parts. Dry forage yield was positively co~related with T‐CWC%. Path‐coefficient analysis suggested CWC% in the stem to be the most important factor affecting total T‐CWC% of the forage at anthesis, and CWC% in the leaf blade to be most important in the regrowth forage. At both harvests CWC% in stems and blades were highly correlated.
Comparison of Emasculation and Nonemasculation for Hybridization of Soybeans1
Authors: Walker A. K. , Cianzio S. R. , Bravo J. A. , Fehr W. R.
Published: July 2010

Emasculation and nonemasculation of the soybean [Glycine max (L.) Merr.] flower for hybridization were compared for percentage of pollinations that produced a pod (percent success), number of seeds per pod, number of selfed seed, percentage of hybrid seed based on total pollinations, and time required for hybridization. Two persons made pollinations with three sets of parents in each of three Iowa and two Puerto Rico environments. The gene controlling flower and hypocotyl color was used to differentiate hybrid and selfed seed.

Average percentage of successful pollinations across environments was significantly greater for nonemasculation (44%) than for emasculation (36%). Average number seeds per pod was similar for the two procedures. The average number of selfed seed was not significantly different for nonemasculation and emasculation. The percentage of hybrid seed based on total pollinations averaged across environments was significantly greater for nonemasculation (94%) than for emasculation (73%). Time saved by not emasculating the female parent permitted at least 10% more flowers to be pollinated per hour than when emasculation was used. Emasculation of soybean flowers prior to pollination is not justified on the basis of these results.
Inheritance of Resistance to Common Bunt in Wheat, C.I. 70901
Authors: Metzger R. J. , Schaller C. W. , Rohde C. R.
Published: July 2010

The wheat line C.I. 7090 (Triticum aestivum L.) was shown by previous work to carry an unidentified gene(s) for resistance to many races of common [Tilletia caries (DC.) Tul. and T. foetida (Wallr) Liro], and dwarf bunt (T. controversa Kuhn). C.I. 7090 was crossed with completely susceptible cultivars (‘Triumph’ and ‘Elgin’) and with bunt‐host differentials. The F3 and F4 progenies of these crosses were analyzed to determine the identity and number of genes involved in resistance. The results showed that a new gene, designated Bt9 was involved and the Bt9 plus Bt7 conferred resistance in C.I. 7090 to 36 of the 41 reported races of common bunt. Inheritance for Bt9 is independent of that for Bt1, 2, 4, 6, and 7.
Genetic Variation and Interrelationships of In Vitro Dry Matter Disappearance and Fiber Content in Orchardgrass Herbage1
Authors: Stratton S. D. , Sleper D. A. , Matches A. G.
Published: July 2010

Forage digestibility, fiber content, and their relationship to animal performance are important aspects of improving forage quality through plant breeding. The objectives of this study were to determine the genetic variation and heritability of in vitro dry matter disappearance(IVDMD), acid detergent fiber (ADF), neutral tergent fiber (NDF), and to examine the interrelationships among these quality factors in orchardgrass (Dactylis glomerata L.) herbage. Fourteen selected orchardgrass parents and their open‐pollinated progenies were transplanted and planted, respectively, into a randomized, complete block experiment at Mt. Vernon, Mo. The forage was analyzed for IVDMD, ADF, and NDF at each of three harvest dates in 1976 and 1977. Parents differed significantly for all of these quality traits. There was less variation among the progenies. Years and harvests within years were significantly different. Narrow‐sense heritabilities ranged from 49 to 91, 21 to 126, and 0 to 110% for IVDMD, ADF, and NDF respectively, suggesting improvement of these traits in the populations studied may be possible through breeding

Correlations of IVDMD, ADF, and NDF with yield were low at the first harvest, but significant in the re‐growth. Maturity was negatively associated with these quality factors at the first harvest date. Stability for these traits between years was favorable
Genetic Variability for Cell Wall Constituents and Associated Quality Traits in Reed Canarygrass1
Authors: Marum P. , Hovin A. W. , Marten G. C. , Shenk J. S.
Published: July 2010

Forage dry matter intake potential by ruminants is negatively associated with its cell wall constituent (CWC) concentration. The objectives of this study were to estimate genetic variance components and determine combining ability and heritability of CWC percent, and other associated quality traits in reed canarygrass (Phalaris arundinacea L.). Genotypic correlations were computed between paired characters. Twelve heterozygous clones used in two 6 ✕ 6 diallels and progenies from 30 crosses were grown for 2 years at two locations with three replicates arranged in randomized complete blocks. One plot consisted of six plants on 91 cm spacing in a row. Infrared spectroscopy was used to determine CWC, acid detergent fiber (ADF), acid detergent lignin (lignin), silica, crude protein, and in vitro digestible dry matter (IVDDM). Separate predictive equations were necessary for each year, probably due to yearly differences in drying procedures of samples. General (GCA) and specific combining ability (SCA) were estimated least squares analysis for one harvest in 1976, two harvests in 1977, and for the mean of the three harvests.

Mean squares for GCA were significant for CWC, ADF, and lignin. Mean squares for SCA were significant for CWC, ADF, lignin, crude protein, and IVDDM. Estimates of variance components due to SCA were nearly twice as large or larger than the variance components due to GCA for CWC, ADF, lignin, crude protein, and IVDDM, indicating the presence of large amounts of nonadditive genetic variance under noncompetitive, spacedplant conditions. Broad‐sense and narrow‐sense heritabilities for CWC were 0.81 and 0.26, respectively.

Estimates of genotypic correlations suggested that: (i) CWC was strongly positively correlated with ADF and lignin and strongly negatively correlated with protein and IVDDM; (ii) ADF had the highest correlation with IVDDM and was closely followed by lignin and CWC, which agreed with other reports using laboratory procedures for estimating these traits; (iii) none of the quality components was strongly correlated with spaced‐plant yield of first growth.
Glandular Trichomes on Medicago Species1
Authors: Kreitner Gerald L. , Sorensen E. L.
Published: July 2010

Glandular hairs have been implicated in resistance of Medicago species to the alfalfa weevil [Hypera postica (Gyllenhal)]. Using light and scanning electron microscopy, we studied the morphology of glands on annuals (diploid M. disciformis DC, tetraploid M. scutellata (L) Mill.) and perennials (diploid M. prostrata Jacq., tetraploids M. sativa L. subsp, sativa and praefalcata) as the itial phase of an investigation to determine the role of glands in resistance.

Erect and procumbent multicellular types with capitatestalked morphology are present. The stalk of erect trichomes is composed of four to six cells including an enlarged basal cell arising from the epidermis. Gland heads contain numerous ceils arranged in distinct tiers. The basal tier contains four cells that constitute about one‐third of the head. Two additional tiers, which together contain 8 to 16 cells, form the remainder of the gland head.

The procumbent trichomes are generally composed of a basal cell embedded in the epidermis, a single stalk cell, and a gland head of four cells in two tiers. The gland curves sharply at the stalk and basal cells, so that much of the axis parallels the adjacent epidermis. The direction of bending is highly stabilized toward the terminal on stems and toward the distal ends of stipules, petioles, leaflets, peduncles, and sepals. Diploid and tetraploid annuals (M. disciformis DC, M. scutellata Mill.) and diploid perennial (M. prostrata Jacq.) contain erect andprocumbent glands. M. sativa L. subsp, sativa (tetraploids, ‘Buffalo’ ‘DuPuits’, ‘Lahontan’, and ‘San Pedro’, and diploid CADL 15) have only procumbent glands. In M. sativa subsp. praefalcata (Sinskaya) C. R. Gunn, erect glands are generally confined to floral structures, with only precumbent glands on vegetative parts. We found a few plants with erect glands on vegetative parts.
Effect of Different Levels of Pollen Production on Polycross Seed Yield in Alfalfa1
Authors: Melton Bill
Published: July 2010

Recent studies have shown relationships among pollen production, and percentages of hybrid seed produced as well as self‐ and cross‐fertility. It was the objective of this study to evaluate pollen production as a possible selection criterion for seed yield in a polycross breeding situation.

A source population of 212 unreplicated plants was evaluated for pollen production using a visual scale of 1 (no dehisced pollen) to 5 (abundant pollen). Five plants were selected within each of pollen indices 1, 3, and 5. These plants were vegetatively propagated and arranged in polycross crossing blocks. Screen cages were used for isolation and honeybees (Apis mellifera) provided pollination. Separate propagules were used for self‐fertility determinations

Self‐fertility and seed yield were greatest on plants with abundant pollen production and lowest on those plants with no visually dehisced pollen. Seed yield did not in. crease in linear pattern according to pollen abundance. Seed production of plants classified as intermediate in pollen abundance was closer to the high than the low pollen producers.

When all plants were combined in the same crossing block, seed yteld of the low pollen producers increased but not to the same level as the other plants. This suggests that factors other than pollen production were involved in determining seed yield of these plants. Pollen production would be a simple and inexpensive selection criterion to eliminate plants with low seed yield potential.
Gibberellin Studies with Sugarcane. II. Hand‐sampled Field Trials1
Authors: Buren L. L. , Moore P. H. , Yamasaki Y.
Published: July 2010

Seven sugarcane (Saceharum sp. hybrids), cultivars grown on 1,600 ha of the four sugarcane growing islands in Hawaii received 140 g/ha gibberellic acid (GA3) in single or in two haft‐rate applications during the wnter of 1976. Stalks harvested 4 to 6 months after the last GA3 application were divided into supposedly responding and non‐responding segments. Analyses of lengths and weights for each segment and for the sum of the three segments showed significant increases due to treatment. The effect of GA3 was not limited to the “responding” segment, so that whole stalk data were necessary to calculate the response of yield to treatment. In addition to increasing weights, GA3 treatments improved the sucrose content of juice. These gains resulted in a calculated yield improvement of 0.93 to 1.47 metric tons sugar/ha.
Genetic Stability of ‘Kenland’ Red Clover During Seed Multiplication1
Authors: Taylor Norman L. , May R. G. , Decker A. M. , Rincker C. M. , Garrison C. S.
Published: July 2010

Foundation and certified seed lots of ‘Kenland’ red clover (Trifolium pretense L.) produced in the western U.S., Kentucky, and Japan were evaluated in Kentucky, Indiana, and Maryland in comparison with Kentucky produced breeder seed to determine the frequency and significance of genetic shifts. Genetic shift toward lower yield and less persistence generally occurred with advancing generation, and was more pronounced in seed lots produced in the southern locations (California and Kentucky). No advantage of third year over second year breeder seed was shown either in performance of the seed lots or their progenies. However, third year certified seed from the southern latitudes was generally less productive than second year seed, presumably because of more opportunity for differential selection in an area of greater genetic shift. Differences in performance of foundation and certified seed lots could not be associated with their parental seed lots. Performance of lots was generally similar at the three evaluation locations except that plant type scores at Indiana were not correlated with yields at the other locations or with regrowth height scores at Indiana. Plant type scores may not be a valid technique for measurement of genetic shifts in Kenland red clover. Percent bloom at Kentucky, and regrowth height at Indiana both in the second year were strongly correlated with forage yields suggesting the use of these efficient non‐laborious ratings for detecting genetic shifts in Kenland. Larger amount of bloom (earliness) was negatively correlated with forage yield corroborating the hypothesis that earlier blooming types are less persistent and lower yielding than late types. In the northern locations longer day length possibly allowed more equal blooming and seed production among genotypes than at southern locations. Measures to insure genetic stability in Kenland red dover should include restriction of seed multiplication to northern locations and strict adherence to present seed certification standards.
An Empirical Approach for the Prediction of Maize F2 Synthetics with Varying Numbers of Lines1
Authors: Marquez‐Sanchez Fidel
Published: July 2010

A method is proposed to predict the yield of an F2 synthetic of maize (Zea mays L.) based on Wright's formula, F2 = F̄1 − F̄1 − P̄)/n. Its basic principle is the fitting of the expected yields of F̄1 and P̄ to asymptotic curves that are functions of the number of lines (n) involved the synthetics. The asymptote of the F1 function is assumed to be the yield (V) of the open‐pollinated cultivar from which the lines are derived, that is, the base population. Although it is not possible to define the limit of the P̄ function, the average (P) of the possible lines derived from the base population may be used. Curves for F̄1 and P̄ were calculated for every n‐line group by selecting the highest yielding F1 synthetic (best F1 synthetic) out of the C (m, n) possible combinations of m lines. The calculated data were fitted to a theoretical asymptotic curve ( a hyperbola) by non‐linear least squares to estimate the corresponding points on the curves. The F2 prediction was a curve with a minimum at n=2, maximum at n=k and a limit V as n increased. A comparison is made between this method and that used by M.L. Kinman and G. F. Sprague in 1945 with data obtained from the Mexican maize breeding program for the humid tropics.
Identification of Multiple Insect Resistant Soybean Lines1
Authors: Hatchett J. H. , Beland G. L. , Kilen T. C.
Published: July 2010

Five soybean [Glycine max (L) Merr.] breeding lines derived from crosses involving P.I. 229358, a plant introduction with multiple insect resistance, were evaluated in a greenhouse or laboratory for leaf‐feeding resistance to the soybean looper (SBL) [Pseudoplusia includens Walker], bollworm (BW) (Heliothis zea Boddie), Mexican bean bettle (MBB) (Epilachna varivestis Mulsant), and tobacco budworm (TBW) (H. virescens Fabricius). The objective of the study was to determine if direct selection for resistance to one or two insect species would result in indirect selection for resistance to other species. P.I. 229358 (resistant parent), ‘Bragg’ (susceptible parent), and ‘Davis’ (highly susceptible check) were used for comparisons. All five breeding fines were as resistant as P.I. 229358 to SBL and BW larvae. Three of the five lines were also as resistant as P.I. 229358 to MBB larvae, based on percentage defoliation and pupal weights. On the basis of larval weights, duration of larval stage, and mortality, three lines were similar to P.I. 229358 in resistance to TBW larvae. Two of the breeding lines were similar to P.I. 229358 in resistance to all four insect species. Because some lines resistant to one, two, or three of the species may not be resistant to other species, identification of breeding lines with multiple insect resistance equal to that in P.I. 229358 should be based on evaluation against each species. These breeding fines could serve as basic germplasm for development of cultivars with multiple insect resistance and would be useful in evaluating the impact of resistance in an overall soybean insect management program.
Lightweight Small‐Plot Sprayer Construction1
Authors: Wolf D. D. , Alls H. L.
Published: July 2010

A push‐type garden cultivator with a single wheel was modified to carry a pressurized air tank, a spray solution tank, adjustable boom, and controls. A ground speed indicator was made from a 6‐Volt bicycle generator connected to a 0 to 3 Volt A.C. panel meter and powered by friction against the bicycle tire. The electrical current generated was proportional to ground speed and indicated travel rate. The entire unit was lightweight, easily disassembled for clean‐up, transport or storage, and was constructed with parts that were available from local retail stores
Inheritance of “Chaffy Head” in Sunflower1
Authors: Brigham Raymond D. , Young J. Keith
Published: July 2010

A sunflower (Helianthus annuus L.) line that produces some plants with heads of vegetative tissue was studied. These completely sterile heads have a massive proliferation of chaffy vegetative tissue where disk florets, and later achenes, usually form. The resulting head is revolute, extremely contorted, more or less globular, and usually splits in the center of the disk early in development. Ray flowers are not present, nor are the usual disk florets. The line was derived from PI 175728 introduced from Turkey. In 1976 normal plants were selfed in segregating nursery rows, and 113 normal: 35 chaffy head plants were observed [χ3(3:1) = 0.144] in 1977. The symbol ch is suggested for this chaffy head character that is apparently conditioned by a single recessive gene.
Maternal Control of Seed Oil Percentage in Sunflower1
Authors: Thompson T. E. , Fick G. N. , Cedeno J. R.
Published: July 2010

Whether maternal genotype or kernel genotype determines seed (achene) oil percentage in sunflower (Helianthus annuus L.) was studied using cytoplasmic male‐sterile and maintainer components of two oilseed and two nonoilseed (confectionery) inbred lines. Genotype the maternal parent controlled oil percentage, and the genotype of the pollen parent had no effect on this characteristic of F1 seed. This was true for determinations made on whole seeds and on kernels alone.

Application of this knowledge in a breeding program means that controlled crosses to determine the value of the maternal genotype for oil production are unnecessary since open‐pollinated seed accurately expresses the genetic potential of any maternal parent. The maternal control further suggests that selection for oil percentage among individual seeds on the same plant is not an effective breeding technique to change oil content.

Pollen parent effects on seed weight, test weight, and percent kernel of seed were also determined. Specific parental combinations and perhaps environment appeared to affect each of these three measuremenets, specially seed weight.
Protein Yield and Its Relationship to Other Traits in Backcross Populations from an Arenas ativa ✕ A. sterilis Cross1
Authors: Takeda K , Frey K. J.
Published: July 2010

Relationships of various traits to protein yield of oats were studied by using F2‐derived lines in the F3 populations from Bc0 through Bc5 of an interspecific oat cross Avena sativa ✕ A. sterilis.

Mean heritabilities ranged from 64 to 68% for heading date and plant height, 45 to 51% for bundle weight, straw yield, grain yield, growth rate, grain number, and protein yield, and 36 to 42% for harvest index, unit straw weight, groat weight, protein percentage, and protein per groat.

Protein percentage had high negative genotypic correlations with grain yield and harvest index and positive genotypic correlations with plant height and protein per groat. Protein yield had genotypic correlations above 0.80 with bundle weight, straw yield, grain yield, growth rate, unit straw weight, and grain number, but it had no correlation with heading date, groat weight, protein percentage, and protein per groat. Thus, grain yield was the primary determinant of variation in protein yield, and protein percentage was negatively associated with grain yield and had little effect on protein yield.

Simulated selection experiments based on the line mean (selection intensity = 5%) showed that selection for protein yield via itself or via grain yield both caused ca. 26% improvement; whereas selection for protein yield via protein percentage caused no improvement.

Protein yield was significantly (P = 0.01)) above the recurrent parent in four oat lines. In three of these increased protein yield was primarily due to increased grain yield. The increased protein yield of the fourth line, however, was due 45% to increased grain yield, 46% to increased protein percentage and 9% to the interaction of these two traits.
Influence of Longevity of Use on Cotton Cultivars' Performance1
Authors: Meredith William R. , Culp T. W.
Published: July 2010

The objective of this study was to determine whether continued use of cotton (Gossypium hirsutum L.) cultivars over 8 to 12 years markedly affected performance. The four cultivars and the year the seed of each was received for evaluation trials were ‘Coker 201’, 1967, 1971, and 1976; ‘Coker 310’, 1969, 1972, and 1976; ‘Stoneville 213’, 1965, 1971, and 1976; and ‘Deltapine 16’ 1967, 1972, and 1976. Seed of the 12 cultivar‐age versions were all produced at Stoneville, Miss. in 1976. In 1977, evaluation trials were grown at two locations each in South Carolina and Mississippi. Cultivars constituted whole plots and the three age versions of each cultivar constituted sub‐plots. Six replications were used in all studies.

No significant differences among age versions were detected for lint yield, 50% fiber length, and fiber strength for any cultivar. However, certain small but statistically significant differences were detected for lint percentage, boll size, seed index, 2.5% fiber length, elongation, and micronaire. No evidence of major changes in cultivar performance with increasing age of the cultivar was detected. Apparently, such factors as inbreeding depression, seed contamination, reselection within a cultivar, and accumulation of seed carrying pathogens were not major problems in the maintenance of cotton cultlvars. Commercial companies appear to have effectively maintained the purity and characteristics of these esablished cotton cultivars.
Direct Application of Ninhydrin Reagent Solution to Exposed Maize Endosperm to Screen for Protein Mutants
Authors: Zorilla Hugo L. , Crane Paul L.
Published: July 2010

The “ninhydrin reagent solution” chemically reacts with the free amino acids present in the exposed maize (Zea mays L.) endosperm to produce a blue color. This study utilized that reaction to search for new mutants and also tested the effectiveness of the use of ninhydrin reagent solution applied to exposed maize endosperm of known opaque‐7 material.

In the search for new mutants, 300 kernels each of 55 collections of maize were tested. In general, there was a lack of ninhydrin penetration on vitreous kernels, but there were exceptions. Sources with floury endosperm type, or a soft crown or “cap” showed good ninhydrin penetration. Lysine content of positive reacting kernels was at the normal level, but protein showed a tendency to higher levels.

Ears of a population with families segregating for opaque‐7 were used to test the practical effectiveness of this ninhydrin technique for mutant screening. Homozygous opaque‐7 testers were used to verify the presence of the opaque‐7 gene. Ears with kernel moistures of 15.6 to 44.1% were tested, but higher moisture levels did not facilitate the penetration of the endosperm tissue by the ninhydrin reagent. In fact, moistures above 35% tended to inhibit the reaction.

Some of the numerous deviations from expectation in this experiment were apparently due to a variety of modifier genes not only masking the opaque‐7 phenotypic expression in varying degrees, but also altering levels of free amino acids. The potential effectiveness of the ninhydrin test in locating any new high lysine mutant would be limited by any interaction between that mutant gene and its genetic background which reduced the level of free amino acids.
Rate and Duration of Growth of Kernels Formed at Specific Florets in Spikelets of Spring Wheat1
Authors: Simmons Steve R. , Crookston R. Kent
Published: July 2010

In an earlier study, large differences in individual kernel weight were observed within spikelets of spring wheat genotypes (Triticum aestivum L. em Thell). To account for these differences, growth rates and effective filling periods were measured in field experiments for kernels formed at each floret position in central spikelets. The genotypes ‘Era’, ‘8037’, and ‘72316’, which differed in kernel weight and kernel number per spikelet, were used. Kernels formed in the fourth and fifth florets (numbered from the spikelet base) displayed significantly lower growth rates than proximal kernels during the period of linear kernel dry matter accumulation. Kernel growth rates during this period over all years, genotypes, and floret positions were significantly correlated with final individual kernel weights.

Another factor that influenced kernel weight within a spikelet was the earlier occurrence of anthesis in the proximal florets compared to distal ones. Kernels formed in proximal florets already had a considerable weight advantage even before the period of linear dry matter accumulation. Effective filling period durations of proximal kernels of Era and 72316 were longer, a probable consequence of the earlier anthesis in these florets. Cessation of dry matter accumulation (and the associated sharp decline in kernel water content) were judged to occur at approximately the same time for all kernels in a spikelet. Additional research oriented toward understanding those factors responsible for establishing kernel growth rate during the linear dry matter accumulation period is advocated.
Evaluation of Seedling Emergence in Cicer Milkvetch by Linear Regression1
Authors: Townsend C. E. , Remmenga E. E. , Dewald C. L. , Ditterline R. L. , Melton B. A. , Smoliak S.
Published: July 2010

We used linear regression to evaluate the stability and adaptability of polycross progenies of cicer milkvetch (Astragalus cicer L.) for seedling emergence in diverse environments. The environments included four sites in Colorado and one each in Montana, Oklahoma, New Mexico, and Alberta, Canada, with 2 or more years of evaluation at some sites. Data from the last two sites were omitted from regression analysis because of extreme variation. Although there were large differences among environments for seedling emergence, several progenies ranked high in all environments. Such progenies were average or above average for stability and could be considered well adapted to most environments. The progeny with the highest average emergence had below average stability because it was poorly adapted to the most unfavorable environment. Soil moisture conditions at planting time and subsequent precipitation greatly influenced seedling emergence. Linear regression was a simple and effective method of demonstrating the relative stability and adaptability of polycross progenies for seedling emergence in these environments.
A Small Plot Combine for Rice1
Authors: Eastin E. F. , Bowling C. C.
Published: July 2010

A small Japanese combine used in rice (Oryza sativa L.) fields in Japan was modified to harvest rice research plots by removing the auger assembly and replacing it with a removable grain collection tray that holds up to 5 kg of grain. The combine cuts a swath 0.8 m wide. Our plots are normally 4 to 7 m long. A crew of two can harvest approximately 60 plots per hour, whereas, it would take the same crew at least 6 hours to hand harvest, thresh, and sack the grain. The combine is equipped with tracks and works well on dry ground or in water; however, if the ground is muddy the soil tends to stick to the tracks and curtail mobility of the combine. The modified combine also has been used to successfully harvest wheat (Triticum aestivum L.) plots but has not been satisfactory for harvesting sorghum (Sorghum bicolor (L.) Moench) or soybean (Glycine max (L.) Merr.) plots.
Responses to Mass Selection in Maize and Stability of Resulting Populations1
Authors: Mareck J. H. , Gardner C. O.
Published: July 2010

Four mass‐selected populations of maize (Zea mays L.), the base population ‘Hays Golden’ (H.G.), and a double cross hybrid check ‘Nebr. 501D’ were evaluated in a range of environments involving five locations and 3 years. The four mass‐selected populations were: C15, the 15th generation of selection for high grain yield; I15, the 15th generation of selection for high grain yield following treatment with thermal neutrons in early cycles of selection; P10, the 10th generation of selection for increased prolificacy; and I14E3, the third generation of selection for yield plus earliness, low ear height, and stalk quality after 14 generations of selection for only high grain yield following irradiation with thermal neutrons.

Mass selection significantly increased grain yield 12 to 15% on the average. When selection was for high grain yield only, correlated increases occurred in prolificacy, days to flower, plant and ear height, and gram mmsture at harvest. Selection for earliness and low ear height in a population previously selected for high grain yield seemed effective without reducing yield. Ten cycles of selection for prolificacy were about as effective in in. creasing yield as 15 generations of selection for yield itself. At the same time, grain moisture did not change and days to flower, plant height and ear height increased less than in selection for yield.

Responses to environment mean yields were all linear and were much greater in mass‐selected populations than in H.G. or in the Nebr. 501D hybrid. Selection appears to have increased the frequencies of those genes which permit genotypes to take advantage of more favorable growing conditions. Under low yield levels caused by heat and drouth, the original population performed as well as or better than mass‐selected populations. However, when grown under favorable conditions, mass‐selected populations had substantially greater yields. Differences in yield responses under varying environments may be related to correlated responses that have occurred in mass selection programs.
Pyro‐Chemiluminescent Differentiation of Oxidized and Reduced N Forms Evolved from Plant Foliage1
Authors: Weiland R. T. , Stutte C. A.
Published: July 2010

Evaluations were made to differentiate the forms of water soluble, non‐elemental nitrogen lost with the trans. piration water vapors from plant foliage. Chemiluminescent detection of chemically bound N, with O2 present as a reactant‐carrier gas, and then absent and replaced with N2 during the pyrolysis of transpiration samples, distinguished the oxidized from the reduced N forms in the transpirate. The majority of the N in several crop and weed species was in the reduced state; however, at least 5% of the N in all species tested was in an oxidized form. The percent of loss of oxidized N was fairly constant in cotton (Gossypium hirsutum L.), ‘Forrest’ beans [Glycine max (L) Merr.], and palmer amaranth [Amaranthus palmeri (S.) Wats.] over the solar day. Older soybean leaf tissue lost a higher percentage of oxidized forms than did younger tissue. Both younger and older soybean tissue evolved greater total amounts of N than foliage in the middle of the plant canopy; yet the rate of transpiration was maximal in the middle foliage. Water‐stressed soybeans evolved greater quantities of oxidized N forms than did irrigated soybeans. The N loss increased in ‘Davis’ soybeans and transpiration decreased in the cultivar ‘Forrest’ as a result of water stress.
Germination Rate and Growth Characteristics of Blue Panicgrass1
Authors: Neal Wright L.
Published: July 2010

Genotypes of blue panicgrass (Panicum antidotale Retz.) previously selected for extremes of fast and slow rate of germination were evaluated for plant growth characteristics. Germination rate and growth characteristics were predictive indicators of the success of plant establishment under arid conditions. Depletion of seed food reserves, elongation of shoots and roots, and production of dry matter were determined during germination and during initial, seedling, and young‐plant growth. Sampling was conducted at various intervals to 54 days in three environments. Nutrient solution and soil provided similar estimates of a positive relationship between germination rate and plant growth characteristics. Selections for fast germination rate showed greater growth rates than selections for slow germination during germination and initial, seedling, and young‐plant growth periods. Selections for fast and slow rate of germination after the seed food reserves were utilized showed increased growth performances with photosynthetic activity. Genetic potential of selections with fast germination rate was reflected in the physiological processes of growth and development. Establishment of blue panicgrass under arid environments could be influenced by germplasm developed for germination rate. After germination and initial growth, seedling plants may provide a competitive advantage to young plants for greater dry matter production.
Effect of Three Ploidy Levels on Meiosis and Mode of Reproduction in Paspalum hexastachyum1
Authors: Quarin Camilo L. , Hanna Wayne W.
Published: July 2010

Chromosome behavior, mode of reproduction, and fertility characteristics were studied in diploid (2n = 12) and colchicine‐induced tetraploid and hexaploid Paspalum hexastachyum Parodi. Diploids could be distinguished from teraploid and hexaploid plants by floret size. Guard cell length and pollen diameter also were useful in identifying ploidy levels. Chromosomes paired mainly as bivalents with an occasional quadrivalent in the diploids; bivalents and quadrivalents in the tetraploids; and bivalents, quadrivalents and hexavalents in the hexaploid. The diploids were sexual but induced tetraploids and hexaploids reproduced by facultative apomixis. Diploid plants were self‐incompatible but cross compatible. The plants were self‐compatible at the tetraploid‐chromosome level.
Effect of Seeding Rates and Row Spacing on Forage and Grain Production of Triticale, Wheat, and Rye1
Authors: Bishnoi U. R.
Published: July 2010

Triticale (X Triticosecale Wittmack) is being used for supplemental winter grazing and has potential to be a grain crop in the southeastern U. S. There is little information on the effect of cultural practices on the agronomic performance of triticale. An experiment was conducted on a Decatur silty clay loam soil (Rhodic Paleudult) to study the effects of two row spacings (12.5 and 25 cm) and three seeding rates (50, 75, and 100 kg/ha) for two growing seasons on the performance of a triticale cultivar, 6TA 131, in comparison with commonly grown Wrens Abruzzi rye (Secale cereale L.) and Arthur 71 wheat (Triticum aestivum L.).

Differences in forage yields due to row spacing and seeding rates of triticale, wheat, and rye were highly significant. The optimum rate of seeding for triticale appears to be 75 and 100 kg/ha for grain and forage production, respectively, when planted at 12.5‐cm row spacings. In wheat and rye, seeding rates of 75 and 100 kg/ha produced significantly more forage, whereas seeding at 50 kg /ha was adequate for grain yields. Clipping effects on triticale and wheat grain yields were inconsistent, but reduced rye yield considerably.
The Sp1 Locus in Soybean Codes for β‐amylase1
Authors: Hildebrand D. F. , Hymowitz T.
Published: July 2010

One hundred F2 soybean [Glycine max (L.) Merrill] seeds from the cross PI 87525 ✕ ‘Ebony’ and 116 cultivars from Maturity Groups 00 through IV were analyzed using polyacrylamide gel electrophoresis and amylase assays to determine whether Sp1a and Sp1b seed protein bands were the same as the slow and fast amylase variant bands. In the PI 87525 ✕ Ebony cross, the slow and fast amylase variant bands had precisely the same segregation ratios and the same electrophoretic mobilities as the Sp1a and Sp1b protein bands. For 114 out of 116 cultivars tested, exact correspondence was obtained for Sp1a and slow amylase bands, and Sp1b and fast amylase bands. ‘Chestnut’ lacked an amylase band, however, the Sp1a seed protein band was present. ‘Altona’ was a mixture of genotypes that lacked or had the amylase band. The Altona genotype that had the fast amylase band also had the Sp1b band. The Altona genotype that lacked an amylase band also lacked a Sp1 seed protein band. From the data obtained, we believe that the slow and fast amylase bands are the Sp1a and Sp1b seed protein bands.

The use of selective α and β‐amylase inhibition and studies of the hydrolysis of amylopectin by the amylase variant support the hypothesis that the Sp1 locus in soybeans codes for β‐amylase.
Gamma Ray Dosage and Mutation Breeding in St. Augustinegrass1
Authors: Busey Philip
Published: July 2010

Stolon pieces of St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] were irradiated with gamma rays in an attempt to cause mutations. A practical dosage for most genotypes was 4,500 fads. This dosage caused considerable (50%) growth retardation and a mean survival of about 40% of single‐node cuttings. However, ‘Bitterblue’ and another accession were entirely killed at 4,000 rads. At 4,500 rads, up to 7% recognizable mutants of accession FA‐243 were obtained. This proportion resulted when irradiated cuttings were propagated clonally and observed for 1.5 years in replicated microplots. In addition, to morphological variants, a chimeral anthocyanin change was noticed. From this chimera arose a stable genotype with green stolons and white stigmas, whereas the source genotype (FA‐243) had red stolons and purple stigmas. Associated reduction in fertility from 56 to 0.6% suggested that the mutation arose as a small chromosome deletion. Mutation breeding is effective in improving St. Augustinegrass when easily recognizable variants are needed.
Seasonal Changes in Morphology and Anatomy of Field‐grown Soybean Leaves1
Authors: Lugg D. G. , Sinclair T. R.
Published: July 2010

The objective of this study was to examine seasonal changes in specific leaf weight (SLW) of soybean (Glycine max [L.] Merrill) leaves and to compare these with changes in leaf area, thickness, and anatomical features. For individual leaves, SLW generally decreased as leaf area increased, and then increased as leaves thickened. In most cases, leaves thickened after the period of greatest leaf area expansion. Specific leaf weight then decreased as leaves senesced. In general, the maximum SLW achieved by each leaf was successively greater with each successive node. Similarly, leaves at upper nodes were thicker than those of the lower nodes. Leaf thickening was largely the result of concurrent thickening of palisade and spongy mesophyll tissues. An important discovery was that in the uppermost, thickest leaves a third layer of palisade mesophyll cells was formed by periclinal division in the outermost palisade layer. The final SLW and leaf thickness obtained were modified by solar radiation levels during the period of leaf development. Differences in radiation distribution seemed to accentuate differences among leaves in 1976 studies and reduce differences in 1977.