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T Hymowitz

Publications and source records attributed to T Hymowitz.

17 recordsLinked to original sources
PubMed2004

SSR marker and ITS cleaved amplified polymorphic sequence analysis of soybean x Glycine tomentella intersubgeneric derived lines.

Wild perennial Glycine species are an invaluable gene resource for the cultivated soybean [ Glycine max (L.) Merr., 2 n=40]. However, these wild species have been largely unexplored in soybean breeding programs because of their extremely low crossability with soybean and the need to employ in vitro embryo rescue methods to produce F(1) hybrids. The objective of this study was to develop molecular markers to identify gene introgression from G. tomentella, a wild perennial Glycine species, to soybean. A selection of 96 soybean simple sequence repeat (SSR) markers was evaluated for cross-specific amplification and polymorphism in G. tomentella. Thirty-two SSR markers (33%) revealed specific alleles for G. tomentella PI 483218 (2 n=78). These SSR markers were further examined with an amphidiploid line (2 n=118) and monosomic alien addition lines (MAALs), each with 2 n=40 chromosomes from soybean and one from G. tomentella. The results show that the use of SSR markers is a rapid and reliable method to detect G. tomentella chromosomes in MAALs. We also developed a cleaved amplification polymorphism sequence (CAPS) marker according to the sequences of internal transcribed spacer (ITS) regions in soybean and G. tomentella. Four MAALs that carry the ITS (rDNA) locus from G. tomentella were identified. The SSR and ITS-CAPS markers will greatly facilitate the introgression and characterization of gene transfer from G. tomentella to soybean.

Base Sequence↗
PubMed2004

Effect of soybean variety and processing on growth performance of young chicks and pigs.

The objective of this study was to determine whether soybeans without the Kunitz trypsin inhibitor and lectins could be fed effectively to young chicks and pigs. Specifically, we compared the growth performance of chicks and pigs fed diets containing modified soybeans: Kunitz trypsin inhibitor-free (KF), lectin-free (LF), lectin and Kunitz trypsin inhibitor-free (LFKF), conventional soybeans (CSB), and commercially obtained, dehulled, solvent-extracted soybean meal (SBM). A 7-d chick experiment was conducted to evaluate the nutritional value of CSB, KF, LF, LFKF, and SBM. The experiment was conducted as a completely randomized design, with four replicates, five treatments, and six male chicks per pen (n = 120). The five treatments consisted of 23% CP dextrose-soybean-based diets containing KF, LF, LFKF, CSB, or SBM as the source of dietary protein. A 28-d pig experiment was conducted to evaluate the nutritional value of CSB, LF, LFKF, and SBM. Pens of four pigs were assigned randomly to a control, corn-SBM, or one of six corn-soybean diets containing raw or extruded soybean varieties as a 2 x 3 factorial arrangement of treatments in a randomized complete block design with five blocks per treatment (n = 140). Chicks fed diets containing any of the raw soybean varieties gained less weight (P < 0.05) than chicks fed SBM (22.81 g/d for SBM vs. 14.17 g/d for the raw soybeans combined). Among the raw soybean treatments, there was a greater effect on growth performance (P < 0.05) by removing both lectins and Kunitz trypsin inhibitor (ADG of 16.56 g for LFKF) than by removing each antinutritional factor separately (ADG of 14.38 and 14.11 g for KF and LF, respectively). Pig growth performance was different (P < 0.001) for SBM (ADG of 409 g) and all the varieties when extruded (ADG of 450 g for CSB, 417 g for LF, and 408 g for LFKF) compared with the raw soybean treatments (ADG of 101 g for CSB, 165 g for LF, and 266 g for LFKF). Among the raw soybean treatments, growth performance improved (P = 0.003) as the antinutritional factor, lectin, was removed from the soybean and improved further (P = 0.045) when both lectins and Kunitz trypsin inhibitor were removed. The growth-inhibiting effect of feeding modified soybeans to young animals was more detrimental for pigs than for chicks in our experiments. Soybeans without the Kunitz trypsin inhibitor and lectins cannot be fed successfully to young chicks and pigs without heating.

Animal Feed↗
PubMed2003

Assignment of molecular linkage groups to soybean chromosomes by primary trisomics.

Gene-linkage groups (classical linkage groups, CLGs; molecular linkage groups, MLGs) and chromosome relationship in soybean [ Glycine max (L.) Merr., 2n = 40] is not yet established. However, primary trisomics provide an invaluable cytogenetic tool to associate genes and linkage groups to specific chromosomes. We have assigned 11 MLGs to soybean chromosomes by using primary trisomics (2 x + 1 = 41) and SSR markers. Primary trisomics were hybridized with Glycine soja Sieb. and Zucc. (2n = 40) in the greenhouse, F(1) plants with 2n = 40 and 41 were identified cytologically and 41 chromosome plants were selfed. A deviation from the 1:2:1 ratio in the F(2) population suggests a marker is associated with a chromosome. Of the possible 220 combinations involving 20 MLGs and 11 primary trisomics, 151 combinations were examined. The relationships between soybean chromosomes and MLGs are: 1 = D1a+q, 3 = N, 5 = A1, 8 = A2, 9 = K, 13 = F, 14 = C1, 17 = D2, 18 = G, 19 = L and 20 = I. This study sets the stage to establish relationship between nine remaining MLGs with the other genetically unidentified nine primary trisomics. The association of CLGs with the soybean chromosomes will be discussed.

Chromosomes, Plant↗
PubMed1999

Nutritional evaluation of lectin-free soybeans for poultry.

This study evaluated the nutritional value of raw lectin-free soybeans in comparison with raw Kunitz trypsin inhibitor-free soybeans, raw conventional soybeans, and commercial heat processed soybean meal (SBM). Analyzed lectin values (milligrams per kilogram) were 7.2, 7.1, and < 0.00015 for the Kunitz-free, conventional, and lectin-free soybeans, respectively. Three experiments were conducted using New Hampshire x Columbian male chicks fed 23% CP dextrose-soybean diets from 8 to 17 d of age. Growth performance of chicks fed lectin-free soybeans was greater (P < 0.05) than that of chicks fed raw conventional soybeans in all three experiments. However, performance of chicks fed lectin-free soybeans was lower than that of chicks fed Kunitz-free soybeans or SBM. The SBM yielded weight gains and feed efficiencies that were much higher than those observed from any of the raw soybeans. True amino acid digestibility and TMEn of the lectin-free and conventional soybeans were determined using the precision-fed cecectomized rooster assay. Seven roosters were crop-intubated with 30 g of soybeans and excreta were collected for 48 h. Digestibility coefficients of most amino acids for lectin-free soybeans were 5 to 8 percentage units higher than those for conventional soybeans, but the differences were not significant (P > 0.05). Likewise, the TMEn for lectin-free soybeans was 11% higher than that for raw conventional soybeans (3.577 vs 3.227 kcal/g DM) but the difference was not significant (P > 0.05). The results of this study indicate that the nutritional value of raw lectin-free soybeans is greater than raw conventional soybeans but is less than raw Kunitz-free soybeans and SBM, suggesting that trypsin inhibitor is a greater antinutritional factor than lectins.

Amino Acids↗
PubMed1997

Phylogenetic and genomic relationships in the genus Glycine Willd. based on sequences from the ITS region of nuclear rDNA.

Phylogenetic relationships among all 18 species of the genus Glycine were inferred from nucleotide sequence variation in the internal transcribed spacer (ITS) region of nuclear ribosomal DNA. Pairwise sequence divergence values ranged from 0.2% (a single nucleotide) between Glycine max and Glycine soja to 8.6% between Glycine hirticaulis and Glycine falcata. The length of the ITS1 and ITS2 sequences ranged from 215 to 238 nucleotides and from 205 to 222 nucleotides, respectively, and that of 5.8S was 168 nucleotides across all the species. Phylogenetic analyses of the ITS region clearly resolved all the genomic groups that were established previously based on cytogenetic and biochemical studies. Based on this study, we assign new genome symbols: HH to Glycine arenaria, H1H1 to Glycine hirticaulis, H2H2 to Glycine pindanica, II to Glycine albicans, and I1I1 to Glycine lactovirens. Parsimony analysis of the entire ITS region, using subgenus Soja as outgroup, resulted in a trichotomy consisting of the clades: G. falcata (F genome), Glycine cyrtoloba and Glycine curvata (C genome), and all other species (A, B, D, E, H, and I genomes) of the subgenus Glycine.

Base Sequence↗
PubMed1992

Effect of heating on nutritional quality of conventional and Kunitz trypsin inhibitor-free soybeans.

Five 10-day chick growth experiments and an amino acid digestibility assay were conducted to assess the effect of steam heating on in vivo protein quality of raw, full-fat Kunitz trypsin inhibitor-free soybeans (KFSB) compared with raw, conventional full-fat soybeans (CSB). Protein solubility in .2% KOH was also evaluated as an in vitro test of in vivo protein quality for underprocessed CSB. The CSB and KFSB were autoclaved for 0, 3, 6, 9, 12, 15, 18, or 21 min at 121 C and 124 kPa. The soybeans were then fed to 8- or 9-day-old chicks as the sole source of protein in dextrose and soybean diets containing 23% protein. Growth performance of chicks fed raw KFSB was superior to that of chicks fed raw CSB. Growth performance of chicks fed autoclaved KFSB or CSB increased and pancreas weight (percentage of body weight) decreased as autoclaving time increased. Slightly less autoclaving time was consistently required to achieve maximum chick performance for KFSB compared with CSB. Less autoclaving time was also required to obtain maximum digestibility of amino acids in KFSB compared with CSB. Urease activity of the soybeans decreased as autoclaving time increased, whereas protein solubility in .2% KOH for CSB did not change consistently in response to heating time. The results of the present study indicate that raw KFSB must be heated to obtain maximum protein quality for chicks and that protein solubility in KOH is not a sensitive indicator of underprocessing of CSB soybeans.

Amino Acids↗
PubMed1991

Effect of heat on the nutritional quality and safety of soybean cultivars.

To evaluate whether soybean strains with reduced levels of trypsin inhibitors have enhanced nutritional and safety characteristics, we measured protease inhibitor content of a standard cultivar (Williams 82) and an isoline (L81-4590) lacking the Kunitz trypsin inhibitor, using enzyme inhibition assays and enzyme-linked immunosorbent assays (ELISA). Less heat was needed to inactivate the remaining trypsin inhibitory activity of the isoline than that of the standard soybean cultivar. In fact, autoclaving (steam heating at 121 degrees C) of the isoline for 20 min resulted in a near zero level of trypsin inhibitor activity, while 20% remained in the Williams 82 sample. Feeding studies with rats showed that the raw soy flour prepared from the isoline was nutritionally superior to the raw flour prepared from the standard variety, as measured by PER and pancreatic weights. Since the content of amino and fatty acids of the flours from both strains was identical and the hemagglutinating activities were within a factor of 2, the increased PER was likely due to the lower level of trypsin inhibitory activity in the isoline. Steam heating the flours for up to 30 min at 121 degrees C progressively increased the PER for both strains. Preliminary screening of several accessions from the USDA Soybean Germplasm Collection showed considerable variation in the content of trypsin inhibitors, sulfur amino acids, and lectins. The BBI content of these cultivars, determined by chymotrypsin inhibition assays, was identical to that found by ELISA. The results indicate that further screening studies could lead to the discovery of soybeans which yield flour that is safe and nutritious, with minimal need for heating.

Amino Acids↗
PubMed1991

Fluorescent in situ hybridization to soybean metaphase chromosomes.

Repetitive DNA sequences were detected directly on somatic metaphase chromosome spreads from soybean root tips using fluorescent in situ hybridization. Methods to spread the forty small metaphase chromosomes substantially free of cellular material were developed using protoplasts. The specific DNA probe was a 1.05 kb internal fragment of a soybean gene encoding the 18S ribosomal RNA subunit. Two methods of incorporating biotin residues into the probe were compared and detection was accomplished with fluorescein-labeled avidin. The rDNA probe exhibits distinct yellow fluorescent signals on only two of the forty metaphase chromosomes that have been counterstained with propidium iodide. This result agrees with our previous analyses of soybean pachytene chromosomes showing that only chromosome 13 is closely associated with the nucleolus organizer region. Fluorescent in situ hybridization with the rDNA probe was detected on three of the forty-one metaphase chromosomes in plants that are trisomic for chromosome 13.

Biotin↗
PubMed1991

Nutritional evaluation of soybeans varying in trypsin inhibitor content.

A series of experiments was conducted to assess, by various methods, the nutritional value of a raw, Kunitz inhibitor-free, low trypsin-inhibitor soybean variant (LTS) in comparison with raw conventional soybeans (RCS) and heated dehulled soybean meal (HDS). The gross energy, protein, and amino acid concentrations of LTS were similar to those of RCS. The protein quality of the soybeans was compared in two trials in which young chicks were fed 9% or 16% CP diets containing one of the soybeans as the sole source of dietary protein. The protein quality of LTS was superior to that of RCS but inferior to that of HDS. True digestibilities of amino acids and TMEn were determined with a precision-fed cockerel assay using conventional and cecectomized birds. No significant effect of bird type on digestibility was found. The mean digestibility of 16 amino acids in RCS, LTS, and HDS was found to be approximately 68, 83, and 92%, respectively. The TMEn of LTS was greater than that of RCS. Chick growth assays indicated that amino acid bioavailability values of lysine and TSAA for LTS were greater than those for RCS but slightly lower than those for HDS. In an additional chick assay with a corn and HDS diet (22% CP), the dietary HDS protein was replaced with LTS or RCS protein at 25, 50, 75, or 100%. Performance of chicks fed LTS was better than that of chicks fed RCS at all replacement levels, but the difference was not significant at the 25% replacement level. Feed efficiencies of chicks fed 25 or 50% of the dietary soybean protein as LTS were not significantly different from that of chicks fed the corn and HDS control diet. The results of the present study indicated that the nutritive value of LTS is substantially greater than that of RCS but somewhat lower than that of HDS.

Amino Acids↗
PubMed1991

Research note: effect of soybeans varying in trypsin inhibitor content on performance of laying hens.

A 6-wk experiment was conducted with commercial laying hens (35 wk of age) to study the effects of feeding raw, conventional, full-fat soybeans (CSB) and raw, Kunitz trypsin inhibitor-free, full-fat soybeans (KFSB) on layer performance. Dietary treatments consisted of corn and soybean meal diets formulated to contain 16% total protein with 100, 72, or 48% of the soybean protein from CSB or KFSB. The remainder of the dietary soybean protein was provided as dehulled soybean meal (DSBM). Egg production, egg weight, egg yield (grams of egg per hen per day) and feed efficiency increased as the level of CSB and KFSB decreased. In general, diets containing KFSB resulted in better performance than those containing CSB. The diet containing 48% of the soybean protein from KFSB yielded performance that was not different (P greater than .05) than that obtained from a corn-DSBM diet. Performance from all other diets was inferior to that from the corn-DSBM diet. Pancreas weight (as a percentage of body weight) was greater for hens fed CSB compared with those fed KFSB, and both were greater than pancreas weight of hens fed the corn-DSBM diet. The dietary treatments had no consistent effect on egg specific gravity or Haugh units.

Animal Feed↗
PubMed1988

Utilization by growing and finishing pigs of raw soybeans of low Kunitz trypsin inhibitor content.

Three trials were conducted to compare acceptance and utilization by growing and finishing pigs of diets containing supplemental protein from either heated, solvent-extracted soybean meal (SBM), raw low-Kunitz trypsin inhibitor soybean (LT) or raw commercially grown Williams cultivar soybean with high Kunitz trypsin inhibitor content (HT). In Trial 1, 36 crossbred pigs, averaging 7 kg in weight, were fed 1) corn-SBM, 2)corn-LT or 3) corn-HT diets for 28 d. Diets were formulated to be isolysinic and to have similar calorie:lysine ratios. Average daily gain and gain/feed were higher (P less than .01) for pigs fed the corn-SBM diet than for pigs fed the corn-LT diet; average daily gain and gain/feed were higher (P less than .01) for the corn-LT diet than for the corn-HT. Average daily feed intake did not differ (P greater than .05) among diets. In Trial 2, 48 crossbred pigs averaging 67 kg were fed diets similar to those in Trial 1 but with lower lysine values. The daily gain (.95 kg) of pigs fed the corn-SBM diet was greater (P less than .05) than for pigs fed the corn-LT diet (.87 kg), which in turn was greater (P less than .05) than for the pigs fed the corn-HT diet (.83 kg). Daily feed intake (kg) and gain/feed were 3.27 and .291, 2.97 and .293, and 3.07 and .270, respectively, for pigs fed the corn-SBM, corn-LT and corn-HT diets. In Trial 3, 18 castrate male pigs averaging 12.4 kg were fed cornstarch-based diets with either SBM, LT or HT as the source of protein.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1986

Genetics and breeding of soybeans lacking the Kunitz trypsin inhibitor.

The major trypsin inhibitor present in soybean [Glycine max (L.) Merrill] seed is the Kunitz trypsin inhibitor or soybean trypsin inhibitor A2 (SBTI-A2). Four forms of SBTI-A2 have been identified in the U.S. soybean germplasm collection. Three of the forms designated Ti(a), Ti(b), and Ti(c) are electrophoretically distinguishable from one another by their different Rf values of 0.79, 0.75, and 0.83, respectively. The three forms are inherited as codominant alleles in a multiple allelic series at a single locus. The fourth form which is the absence of SBTI-A2 is found in P.I. 157440 and P.I. 196168. The allele lacking SBTI-A2 is designated ti and is inherited as a simple recessive to the other three SBTI-A2 forms. Tia is the most common SBTI-A2 allele in the germplasm collection. Ti(b) primarily is found in Japan and Korea. Ti(c) is associated with the Tohoku District, Japan. P.I. 157440 and P.I. 196168 are from Korea. Linkage studies revealed that the Ti and Ap loci are linked by 16.2 +/- 1.5 map units. Three isolines of soybeans lacking the Kunitz trypsin inhibitor, derived by backcrossing P.I. 157440 to three commercial cultivars (Ti(a)Ti(a)), were released to the research community. Results of preliminary feeding trials, with chicks and young pigs, revealed that gain/feed was significantly higher in lines lacking the Kunitz trypsin inhibitor than cultivars containing the inhibitor. However, the gain/feed was lower in both feeds than commercially processed soybean meal.

Animals↗
PubMed1980

Response of young chicks to raw, defatted, Kunitz trypsin inhibitor variant soybeans as sources of dietary protein.

Two trials, using 264 8-day-old male crossbred chicks, were conducted to evaluate the nutritional value of two trypsin-inhibitor (Kunitz) variant soybeans. These two variants, designated PI 157440 (PI) and number 661, have lower trypsin-inhibitor activities than do US commercially grown soybean cultivars such as Amsoy 71. Raw PI, 661, and Amsoy 71 soybeans were defatted and then compared to a commercially processed solvent extracted soybean meal (SBM) using purified diets with soybeans or SBM as the sole source of protein. Trials 1 and 2, respectively, were of 6 and 7 days duration. SBM was superior to each of the raw meals. In Trial 1, gain/feed was higher from PI than from Amsoy 71. In Trial 2, gain and gain/feed were higher (P < .05) from PI and 661 than from Amsoy 71. Pancreas weight as a percent of body weight reflected the trypsin-inhibitor intake. The addition of .3% DL-methionine to each diet improved (P < .05) gain and gain/feed. In Trial 2 gain and gain/feed from PI plus methionine was greater (P < .05) than from 661 plus methionine. In both trials, raw PI plus 3% methionine produced gain and gain/feed comparable to SBM without added methionine.

Animal Nutritional Physiological Phenomena↗
PubMedDate not supplied

Association of the yellow leaf (y10) mutant to soybean chromosome 3.

At least 19 single recessive gene yellow leaf mutants and one duplicate recessive gene mutant have been described in soybean. This study was conducted to associate a yellow leaf mutant, y10, with a specific soybean chromosome by using primary trisomics (2n = 41). Seven soybean primary trisomics were hybridized as female parent with genetic stock strain, T161, carrying y10. F(1) disomic and primary trisomic plants were identified cytologically. One disomic (control) and all primary trisomic plants were allowed to self-pollinate and F(2) populations were classified for green versus yellow leaf mutant. The F(2) population of Triplo 3 segregated in a 17:1 ratio, while a disomic (3:1) ratio was observed with Triplo 8-, 17-, 18-, and 20-derived F(2) populations, suggesting that the y10 locus is on chromosome 3. The y10 locus was examined with four simple sequence repeat (SSR) markers (Satt584, Sat_033, Satt387, and Satt022) from molecular linkage group (MLG) N and y10 was found linked with Satt022. Therefore we confirmed the association of MLG N with chromosome 3. The possible association of y10 with Triplo 16 and Triplo 19 are discussed.

Chromosome Mapping↗
PubMedDate not supplied

Pollen from Glycine species survive cryogenic exposure.

Pollen of 12 genotypes of the annual soybean and its wild perennial relatives were stored without pre-desiccation at low temperatures (-20 C and -196 C) and tested for their viability in vitro. The influence of cryopreserved pollen on pod set and seed production was also investigated. Cryopreserved pollen of all the genotypes showed germination in vitro. Pollen of annual soybean stored at -20 C retained their viability for 4 months, however, pollen of its wild perennial relatives at same storage conditions failed to germinate in vitro. Flowers pollinated with cryopreserved pollen had similar pod set and number of seeds/pod as those pollinated with fresh pollen. Results of this study suggest that cryopreservation of pollen can be used successfully for soybean breeding, and also offers the possibility of conserving the haploid gene pool of soybean and wild perennial species in a cryobank facility.

Adaptation, Physiological↗