Genetic analysis of salt tolerance during germination in Lycopersicon

Summary The salt-tolerant cultivated tomato (Lycopersicon esculentum) accession, PI174263, and a sensitive cv, UCT5, were crossed to develop reciprocal F₁, F₂ and BC₁ populations for genetic analysis of salt tolerance in tomatoes during seed germination. Variation was partitioned into embryo, endosperm and maternal (testa and cytoplasmic) components. Generation means analysis indicated that there were no significant embryo (additive, dominance or epistatic) effects on germination performance under salt stress. Highly significant endosperm additive and testa dominance effects were detected. The proportion of the total variance explained by the model containing these two components was R²=98.2%. Variance component analysis indicated a large genetic variance with additive gene action as the predominant component. Furhter inspection indicated that this variance was attributable to endosperm additive effects on germinability under salt stress. Narrow-sense heritability was estimated as moderately high. Implications for breeding procedures are discussed.     

Analysis of cytoplasmic and maternal effects I. A genetic model for diploid plant seeds and animals

A genetic model for modified diallel crosses is proposed for estimating variance and covariance components of cytoplasmic, maternal additive and dominance effects, as well as direct additive and dominance effects. Monte Carlo simulations were conducted to compare the efficiencies of minimum norm quadratic unbiased estimation (MINQUE) methods. For both balanced and unbalanced mating designs, MINQUE (0/1), which has 0 for all the prior covariances and 1 for all the prior variances, has similar efficiency to MINQUE(), which has parameter values for the prior values. Unbiased estimates of variance and covariance components and their sampling variances could be obtained with MINQUE(0/1) and jackknifing. A t-test following jackknifing is applicable to test hypotheses for zero variance and covariance components. The genetic model is robust for estimating variance and covariance components under several situations of no specific effects. A MINQUE(0/1) procedure is suggested for unbiased estimation of covariance components between two traits with equal design matrices. Methods of unbiased prediction for random genetic effects are discussed. A linear unbiased prediction (LUP) method is shown to be efficient for the genetic model. An example is given for a demonstration of estimating variance and covariance components and predicting genetic effects.     

Inheritance of resistance to blackmold (Alternaria alternata (Fr.) Keissler) in two interspecific crosses of tomato (Lycopersicon esculentum ×L. cheesmanii f.typicum)

Inheritance of resistance to blackmold, a disease of ripe tomato fruit caused byAlternaria alternata, was studied in two interspecific crosses. The parents, F₁ and F₂ generations of a cross between the susceptibleLycopersicon esculentum Mill. cultivar Hunt 100 and the resistantL. Cheesmanii f.typicum Riley accession LA 422, and the parents, F₁, F₂, F₃, and BC₁ P₂ generations of a cross between the susceptibleL. Esculentum cv. VF 145B-7879 and LA 422 were evaluated. The following disease evaluation traits were used: symptom rating (a symptom severity rating based on visual evaluation of lesions), diseased fruit (the number of diseased fruits divided by the total number of fruit scored), and lesion size (a function derived from the actual lesion diameter). Generation means analysis was used to determine gene action. The data of the Hunt 100 × LA 422 cross fit an additive-dominance model for all three traits. The VF 145B-7879 × LA 422 cross data best fit a model that included the additive × additive and additive × dominance interaction components for the trait diseased fruit, whereas higher-order epistatic models would have to be invoked to fit the data for the traits symptom rating and lesion size. A minimum of one gene segregated for all three traits. Broad-sense heritability estimates ranged from 0.09 to 0.16 for all three traits, indicating that selection for improved resistance to blackmold will require selection on a family performance basis.     

Properties of components of covariance of inbred relatives and their estimates in a maize population

Summary Properties of three parameterizations, denoted as the C-model, D-model and Q-model, for covariances of inbred relatives under assumptions of no linkage or epistasis are explored and compared. Additive variance in an inbred population with inbreeding coefficient F, ² _AF =(1+F) ² _A where ² _A is additive variance in a panmictic population, if Q-model parameters Q _xx and Q _xy are both zero. Conditions sufficient for this to hold are presented in terms of gene frequencies and dominance contrasts (homozygotes vs. heterozygotes). Some other properties and potential uses of estimates of components in the models are also discussed. Estimates of components in the D-model and Q-model were calculated from a maize (Zea mays L.) study from which estimates of components in the C-model were previously published. Of particular interest were the covariance (Q _xy ) of effects of alleles at complete homozygosity with inbreeding depression effects, the covariance (D ₁) of additive effects at panmixia with inbreeding depression effects and the within-locus variance (D ₂, alias Q _xx ) of inbreeding depression effects. Estimates of Q _xy , D ₁, and D ₂ were small and nonsignificant in most cases. For ear height in the second year of the study, D ₂ appeared to be a major component. In some cases, results were obtained which had contradictory implications (negative D ₂ coupled with positive Q _xy or D ₁, and positive D ₂ coupled with negative ² _D ). A negative estimate of one or the other of ² _D or ² _A was obtained in one of the two within-year analyses for every character. Problems in getting realistic results were thought to be owing to excessive multicollinearity among the coefficients of the components in the expectations of the covariances of the kinds of relatives included in the study. Implications for future studies of this kind are discussed.Journal Article No. 87-3-14 of the Kentucky Agricultural Experiment Station published with the approval of the Director     

The mechanism of object fixation and its relation to spontaneous pattern preferences in Drosophila melanogaster

The orientation behavior of walking flies, Drosophila melanogaster, towards a single 6° wide black vertical stripe (elementary stripe) can be explained by use of the turning tendency function H(). This function is characterized by maximal values at an angular distance of =25° from the stable zero position (=orienting direction), a sharp decline from this maximum to =60°, and a very slow approach to the unstable zero position (Horn and Wehner, 1975). The shape of this function is influenced by both translatory and rotatory components of movement. If the translatory component is minimized by measuring the turning function W() (see 2.3) at a distance of 10 mm (C1) from the center of the arena, a change in the strength of this decline is caused. But with increasing translatory component, i.e. at a greater distance from the center of the arena, W() approximates the heuristical function H() (Fig. 12). The turning functions W() are pattern-specific; the angular positions of the maximum responses shift to greater angles with increasing width of the patterns (Fig. 2). In the twopattern configuration with double or single stripes, there is always a coincidence between the stable zero positions of W (), the mean of the frequency distributions P() of the flies' positions and n _g() of the straight courses, and the stable zero positions of H () obtained from an additive superposition of two or more angular shifted turning tendency functions H() (Fig. 5, 7). Therefore, the mean positions of the flies in a multi-stripe experiment composed of elementary stripes can be predicted from the addition of many angular shifted turning tendency functions H(). Between H() and the frequency distribution P() of the flies' positions , the following formula holds: P() =C·H()d (Fig. 13). With this equation, the spontaneous preference of the broader of two double stripes can be explained presuming lateral interactions between the components of the patterns (Fig. 8, 10). The strength x _i ^* of this lateral interaction depends on the width of the double stripes. The greater , the smaller is x _i ^* . x _i ^* is a pattern-specific value (Table 1, 2).Supported by the Deutsche Forschungsgemeinschaft, Ho 664/2     

Estimates of ϕ and ψ torsion angles in proteins from one-, two- and three-bond nuclear spin-spin couplings: Application to staphylococcal nuclease

Summary Calculated coupling constants (³J_H ^N _H , ¹J_{C H} , ²J_CH , ¹J_{C N} and ²J_{C N}) from our accompanying paper [Edison, A.S. et al. (1994) J. Biomol. NMR, 4, 519–542] have been used to generate error surfaces that can provide estimates of the and angles in proteins. We have used experimental coupling data [³J_H ^N _H : Kay, L.E. et al. (1989) J. Am. Chem. Soc., 111, 5488–5490; ¹J_{C H} : Vuister, G.W. et al. (1993) J. Biomol. NMR, 3, 67–80; ²J_CH : Vuister, G.W. and Bax, A. (1992) J. Biomol. NMR, 2, 401–405; ¹J_{C N} and ²J_{C N}: Delaglio, F. et al. (1991) J. Biomol. NMR, 1, 439–446] to create error surfaces for selected residues of the protein staphylococcal nuclease. The residues were chosen to include all those with five experimental couplings, as well as some with four experimental couplings, to demonstrate the relative importance of ³J_H ^N _H and ¹J_{C H} . For most of the cases, we obtained good agreement between the X-ray structure [Loll, P.J. and Lattman, E.E. (1989) Protein Struct. Funct. Genet., 5, 183–201] and the NMR data.Abbreviations CUPID Contin Uous ProbabIlity Distribution analysis of rotamers - ⁿJ_AB single-bond (n=1), geminal (n=2), or vicinal (n=3) coupling constant between nuclei A and B - NOE nuclear Overhauser enhancement - r² correlation coefficient     

Heteronuclear relayed E.COSY applied to the determination of accurate 3J(HN,C′) and 3J(Hβ,C′) coupling constants in Desulfovibrio vulgaris flavodoxin

Summary A simple constant-time 3D heteronuclear NMR pulse sequence has been developed to quantitatively determine the heteronuclear three-bond couplings ³J(H^N,C) and ³J(H,C) in uniformly ¹³C-enriched proteins. The protocols for measuring accurate coupling constants are based on ¹H,¹³C-heteronuclear relayed E.COSY [Schmidt, J.M., Ernst, R.R., Aimoto, S. and Kainosho, M. (1995) J. Biomol. NMR, 6, 95–105] in combination with numerical least-squares spectrum evaluation. Accurate coupling constants are extracted from 2D spectrum projections using 2D multiplet simulation. Confidence intervals for the obtained three-bond coupling constants are calculated from F-statistics. The three-bond couplings are relevant to the determination of and X ₁ dihedral-angle conformations in the amino acid backbone and side chain. The methods are demonstrated on the recombinant ¹³C, ¹⁵N-doubly enriched 147-amino acid protein Desulfovibrio vulgaris flavodoxin with bound flavin mononucleotide in its oxidized form. In total, 109 ³J(H^N,C) and 100 ³J(H,C) coupling constants are obtained from a single spectrum.Abbreviations ANOVA analysis of variances - COSY correlated spectroscopy - E.COSY exclusive correlation spectroscopy - FMN flavin mononucleotide - HMQC heteronuclear multiple-quantum coherence - HSQC heteronuclear single-quantum coherence     

Genetic analysis of carbon isotope discrimination and agronomic characters in a bread wheat cross

Carbon isotope discrimination () has been suggested as a selection criterion to improve transpiration efficiency (W) in bread wheat (Triticum aestivum L.). Cultivars Chinese Spring with low A (high W) and Yecora Rojo with high (low W) were crossed to develop F₁, F₂, BC₁, and BC₂ populations for genetic analysis of and other agronomic characters under well-watered (wet) and water-stressed (dry) field conditions. Significant variation was observed among the generations for only under the wet environment. Generation x irrigation interactions were not significant for . Generation means analysis indicated that additive gene action is of primary importance in the expression of under nonstress conditions. Dominance gene action was also detected for , and the direction of dominance was toward higher values of . The broad-sense and the narrow-sense heritabilities for were 61 % and 57% under the wet conditions, but were 48% and 12% under the draughted conditions, respectively. The narrow-sense heritabilities for grain yield, above-ground dry matter, and harvest index were 36%, 39%, and 60% under the wet conditions and 21%, 44%, and 20% under dry conditions, respectively. The significant additive genetic variation and moderate estimate of the narrow-sense heritability observed for indicated that selection under wet environments should be effective in changing in spring bread wheat.     

Lactate conversion to acetate,CO2 and H2 in cell suspensions of Desulfovibrio vulgaris (Marburg): indications for the involvement of an energy driven reaction

Cell suspensions of Desulfovibrio vulgaris were found to catalyze, in the absence of sulfate, the complete conversion of 1 lactate to 1 acetate, 1 CO₂, and 2 H₂ (G₀=-8.8 kJ/mol) and of 1 pyruvate to 1 acetate, 1 CO₂, and 1 H₂ (G₀=-52 kJ/mol). Protonophores, the proton translocating ATPase inhibitor N,N-dicyclohexylcarbodiimide, and arsenate specifically inhibited H₂ formation from lactate but not from pyruvate. The results suggest that lactate oxidation to pyruvate and H₂ (G ₀=+43.2 kJ/mol) is energy driven.     

Structure and function of H+-ATPase

(1) Extensive studies on proton-translocating ATPase (H⁺-ATPase) revealed that H⁺-ATPase is an energy transforming device universally distributed in membranes of almost all kinds of cells. (2) Crystallization of the catalytic portion (F₁) of H⁺-ATPase showed that F₁ is a hexagonal molecule with a central hole. The diameter of F₁ is about 90 Å and its molecular weight is about 380,000. (3) Use of thermophilic F₁ permits the complete reconstitution of F₁ from its five subunits (, , , , and ) and demonstration of the gate function of the -complex, the catalytic function of (supported by and ), and the H⁺-translocating functions of all five subunits. (4) Studies using purified thermostable F₀ showed that F₀ is an H⁺-channel portion of H⁺-ATPase. The direct measurement of H⁺-flux through F₀, sequencing of DCCD-binding protein, and isolation of F₁-binding protein are described. (5) The subunit stoichiometry of F₁ may be ₃₃. (6) Reconstitution of stable H⁺-ATPase-liposomes revealed that ATP is directly synthesized by the flow of H⁺ driven by an electrochemical potential gradient and that H⁺ is translocated by ATP hydrolysis. This rules out functions for all the hypothetical components that do not belong to H⁺-ATPase in H⁺-driven ATP synthesis. The roles of conformation change and other phenomena in ATP synthesis are also discussed.     

Electron transport reactions in respiratory particles of hydrogenase-induced Anacystis nidulans

Respiratory particles from hydrogen-grown Anacystis nidulans were found to oxidize H₂, NADPH, NADH, succinate and ascorbate plus N,N,N,N-tetramethyl-p-phenylenediamine at rates corresponding to 28, 15, 6, 2.5, and 70 nmol O₂ taken up x mg protein^–1xmin^–1, respectively. The particles were isolated by brief sonication of lysozyme-pretreated cells. Respiratory activities were studied in terms of both substrate oxidation and O₂ uptake. The stoichiometry between oxidation of H₂, NADPH, NADH or succinate, and consumption of O₂ was calculated to be 1.95+-0.1 with each substrate.Inhibitors of flavoproteins did not affect the oxyhydrogen reaction while 2-n-heptyl-8-hydroxyquinoline-N-oxide as well as compounds known to block the terminal oxidase impaired the oxidation of both H₂ and of NAD(P)H or succinate in a parallel fashion. No additivity of O₂ uptake was observed when NADPH, NADH or succinate was present in addition to H₂. Instead, H₂ uptake was depressed under such conditions, and also the oxidation of NAD(P)H or succinate was increasingly lowered by increasing H₂ tensions.The results suggest that in Anacystis molecular hydrogen is oxidized through the same type of respiratory chain as are NAD(P)H and succinate. Moreover, the cyanide-resistant branch of respiratory O₂ uptake will be discussed, and a few results obtained with particles prepared from thylakoid-free Anacystis will also be presented.Abbreviations BAL 2,3-dimercaptopropanol-(1) - DCPIP 2,6-dichlorophenolindophenol - HOQNO 2-n-heptyl-8-hydroxyquinoline-N-oxide - TMPD N,N,N,N-tetramethyl-p-phenylenediamine - tricine N-tris-(hydroxymethyl)-methylglycine - Tris tris-(hydroxymethyl)-aminomethane - TTFA thenoyltrifluoroacetone NAD(P)H indicates NADPH and/or NADH     

Polymorphism and mapping of the class II genes in the rat: RT1.B,RT1.D,and RT1.H,a new DP-like region

The major histocompatibility complex of the rat (RTI) encodes the class II molecules involved with antigen presentation and cell to cell communication. The organization of these class II genes has been studied by Southern blot hybridization using genomic DNA from inbred and recombinant rat strains digested with various restriction endonuclease and hybridized under stringent conditions with probes for mouse class II and human class II genes. Analysis of the restriction fragment length polymorphisms has mapped the class II genes relative to each other. We have confirmed the order of the - and -chain genes in the RT1.B region, mapped the RT1.D region relative to RT1.B and showed that it has - and -chain loci, and identified a new HLA-DP-like locus, RT1.H, to the RT1.A side of RT1. B. The RT1. H and RT1.H genes map to the region around the recombination point in R22, and there appears to be a hot spot of recombination in RT1.H. The H and D genes have high levels of polymorphism; B , B ,and H have intermediate levels of polymorphism, and D has a low level of polymorphism.     

Indigoidine and other bacterial pigments related to 3,3′-bipyridyl

Zusammenfassung Die extracelluläre Abscheidung eines unlöslichen blauen Pigments (Indigoidin) wurde zuerst bei Pseudomonas indigofera beobachtet. Historisch wird auf die verschiedenen Benennungen dieses Bakteriums eingegangen. Beschrieben wird die Darstellung blauer Farbstoffe aus Kulturen verschiedener Bakterien. Die von Corynebacterium insidiosum, Arthrobacter atrocyaneus und Arthrobacter polychromogenes gebildeten Pigmente sind identisch mit Indigoidin von P. indigofera. Die Identität wird bewiesen durch physikalische und chemische Vergleiche der Pigmente und ihrer Derivate. Der Name Indigoidin, der früher nur für das Pigment von P. indigofera verwendet wurde, wird nun unabhängig von der Herkunft des Pigments benützt.Indigoidin (I), C₁₀H₈N₄O₄, ist 5,5-Diamino-4,4-dihydroxy-3,3-diazadiphenochinon-(2,2). Durch Erhitzen mit 6 n HCl entsteht daraus ein Hydrolyseprodukt (III), C₁₀H₆N₂O₆, das als 4,5,4,5-Tetrahydroxy-3,3-diazadiphenochinon-(2,2) erkannt wurde. Dieses Hydrolyseprodukt (III) bildet ein Monokaliumsalz (VII), das identisch ist mit dem grünen Pigment, das Arthrobacter crystallopoietes bei Zusatz von Pyridon-(2) bildet. Über Synthesen des Indigoidins (I) und seines Hydrolyseprodukts (III), die von 3,3-Bipyridyl, von Citrazinsäure oder 5-Amino-pyridon-(2) ausgehen, wird an anderer Stelle berichtet.Beschrieben wird die Darstellung folgender Indigoidin-Derivate: 5,5-Diacetamino-4,4-dihydroxy-3,3-diazadiphenochinon-(2,2) (II), C₁₄H₁₂N₄O₆; 4,4-Dihydroxy-5,5-diacetoxy-3,3-diazadiphenochinon-(2,2) (IV), C₁₄H₁₀N₂O₈; 2,5,6,2.5.6-Hexaacetoxy-3,3-bipyridyl (VI), C₂₂H₂₀N₂O₁₂ und 4,4-Dihydroxy-5,5-dimethoxy-3,3-diazadiphenochinon-(2,2) (V), C₁₂H₁₀N₂O₆.     

Labdane diterpene derivatives from Holwaya mucida

Clumps of white crystals present in 40-day-old malt agar cultures of Holwaya mucida were isolated as long white needles by crystallization from ethanol following short extraction with chloroform. The levorotary compound ([] ₂₈₉ ²¹ =-193.8°) was recognized as a -lactone (C₁₇H₂₀O₅) by infrared and mass spectrometry. It was identified as 7-methoxy-3a, 10b-dimethyl-1, 2, 3, 3a, 5a, 7, 10b, 10c-octahydro-4H, 9H-furo[2, 3, 4 : 4, 5]naphtho[2, 1-c]pyran-4, 9-dione, a labdane-derived compound known as antibiotic LL-Z1271. Preparative thin-layer chromatography of the mother liquor afforded 2 minor metabolites. One was identified as LL-Z1271, the demethylated analogue of LL-Z1271. The other one named LL-Z1271, was recognized as a compound related to and : its structure could not be fully elucidated. H. mucida (anamorph: Crinula calciiformis) has no taxonomic relationship with two other LL-Z1271 producing species viz. Acrostalagmus sp. (= Acremonium cf. atrogriseum) and Oidiodendron truncatum.     

Energetics of syntrophic ethanol oxidation in defined chemostat cocultures

The ethanol-oxidizing, proton-reducing Pelobacter acetylenicus was grown in chemostat cocultures with either Acetobacterium woodii, Methanobacterium bryantii, or Desulfovibrio desulfuricans. Stable steady state conditions with tightly coupled growth were reached at various dilution rates between 0.02 and 0.14 h^-1. Both ethanol and H₂ steady state concentrations increased with growth rate and were lower in cocultures with the sulfate reducer < methanogen < homoacetogen. Due to the higher affinity for H₂, D. desulfuricans outcompeted M. bryantii, and this one A. woodii when inoculated in cocultures with P. acetylenicus. Cocultures with A. woodii had lower H₂ steady state concentrations when bicarbonate reduction was replaced by the energetically more favourable caffeate reduction. Similarly, cocultures with D. desulfuricans had lower H₂ concentrations with nitrate than with sulfate as electron acceptor. The Gibbs free energy (G) available to the H₂-producing P. acetylenicus was independent of growth rate and the H₂-utilizing partner, whereas the G available to the latter increased with growth rate and the energy yielding potential of the H₂ oxidation reaction. The critical Gibbs free energy (G_c), i.e. the minimum energy required for H₂ production and H₂ oxidation, was-5.5 to-8.0 kJ mol^-1 H₂ for P. acetylenicus,-5.1 to-6.3 kJ mol^-1 H₂ for A. woodii,-7.5 to-9.1 kJ mol^-1 H₂ for M. bryantii, and-10.3 to-12.3 kJ mol^-1 H₂ for D. desulfuricans. Obviously, the potentially available energy was used more efficiently by homoacetogens > methanogens > sulfate reducers.     

Interconversion of F430 derivatives of methanogenic bacteria

F₄₃₀ is the prosthetic group of the methylcoenzyme M reductase of methanogenic bacteria. The compound isolated from Methanosarcina barkeri appears to be identical to the one obtained from the only distinctly related Methanobacterium thermoautotrophicum. F₄₃₀ is thermolabile and in the presence of acetonitrile or C10 _in4 ^sup- two epimerization products are obtained upon heating; in the absence of these compounds F₄₃₀ is oxidized to 12, 13-didehydro-F₄₃₀. The latter is stereoselectively reduced under H₂ atmosphere to F₄₃₀ by cell-free extracts of M. barkeri or M. thermoautotrophicum. H₂ may be replaced by the reduced methanogenic electron carrier coenzyme F₄₂₀.Abbreviations CH₃S-CoM methylcoenzyme M, 2-methylthioethanesulfonic acid - HS-CoM coenzyme M, 2-mercaptoethanesulfonic acid - F₄₃₀ Ni(II) tetrahydro-(12, 13)-corphin with a uroporphinoid (III) ligand skeleton - 13-epi-F₄₃₀ and 12,13-di-epi-F₄₃₀ the 12, 13- and 12, 13-derivatives of F₄₃₀ - 12, 13-didehydro-F₄₃₀ F₄₃₀ oxidized at C-12 and C-13 - coenzyme F₄₂₀ 7,8-didemethyl-8-hydroxy-5-deazaflavin derivative - coenzyme F₄₂₀H₂ reduced coenzyme F₄₂₀ - MV⁺ methylviologen semiquinone - HPLC high-performance liquid chromatography     

Aliphatic 1H and 13C resonance assignments for the 26-10 antibody VL domain derived from heteronuclear multidimensional NMR spectroscopy

Summary Extensive ¹H and ¹³C assignments have been obtained for the aliphatic resonances of a uniformly ¹³C-and ¹⁵N-labeled recombinant V_L domain from the anti-digoxin antibody 26-10. Four-dimensional triple resonance NMR data acquired with the HNCAHA and HN(CO)CAHA pulse sequences [Kay et al. (1992) J. Magn. Reson., 98, 443–450] afforded assignments for the backbone H^N, N, H and C resonances. These data confirm and extend H^N, N and H assignments derived previously from three-dimensional ¹H-¹⁵N NMR studies of uniformly ¹⁵N-labeled V_L domain [Constantine et al. (1992), Biochemistry, 31, 5033–5043]. The identified H and C resonances provided a starting point for assigning the side-chain aliphatic ¹H and ¹³C resonances using three-dimensional HCCH-COSY and HCCH-TOCSY experiments [Clore et al. (1990), Biochemistry, 29, 8172–8184]. The C and C chemical shifts are correlated with the V_L domain secondary structure. The extensive set of side-chain assignments obtained will allow a detailed comparison to be made between the solution structure of the isolated V_L domain and the X-ray structure of the V_L domain within the 26–10 Fab.     

Genetic evaluation with autosomal and X-chromosomal inheritance

Summary At present, genetic evaluation in livestock using best linear unbiased prediction (BLUP) assumes autosomal inheritance. There is evidence, however, of X-chromosomal inheritance for some traits of economic importance. BLUP can accommodate models that include X-chromosomal in addition to autosomal inheritance. To obtain BLUP with autosomal and X-chromosomal additive inheritance for a population in which allelic frequency is equal in the sexes, and that is in gametic equilibrium, we write y _i = x_i + a_i + s_i + e_i, where y _i is the phenotypic value for individual i, x_i, is a vector of constants relating y _i to fixed effects, is a vector of fixed effects, a _i is the additive genetic effect for autosomal loci, S _i is the additive genetic effect for X-chromosomal loci, and e _i is random error. The covariance matrix of a _i's is A _A ² , where A is the matrix of twice the co-ancestries between relatives for autosomal loci, and _A ² is the variance of additive genetic effects for autosomal loci. The covariance matrix of s _i's is S _F ² , where S is a matrix of functions of co-ancestries between relatives for X-chromosomal loci and _F ² is the variance of additive genetic effects for X-chromosomal loci for noninbred females. Given the covariance matrices of random effects a _i, s_i, and e _i, BLUPs of autosomal and of X-chromosomal additive effects can be obtained using mixed model equations. Recursive rules to construct S and an efficient algorithm to compute its inverse are given.Dedicated to the memory of Dr. C. R. Henderson, whose encouraging comments stimulated the research in this paper. Supported in part by the Illinois Agricultural Experiment Station, Hatch Project 35-0367, Estimation of Genetic Parameters.     

Inheritance of heading date,plant height,ear length and spikelets per spike in an intervarietal cross of wheat

Summary A study to obtain information on early segregating generations of an intervarietal cross WG 357 X Tobari 66 in spring wheat on the genetics of days to heading, plant height, ear length and spikelets per spike was conducted. WG 357 has amber, hard and lustrous grains and is a well adapted high yielding variety of North India whereas Tobari 66 is red grained introduction from CIMMYT.The parental F₁, F₂, B₁, B₂, biparentals, F₃ (parents of biparentals), F₃ bulk and F₄ bulk generations were studied in order to provide analysis of generations means (Mather 1949; Hayman 1958) and variance component analysis (Kearsay 1965; Perkins and Jinks 1970).There were highly significant differences among the generations for all the characters studied. There were significant differences among the F₃ lines as well as among the biparental progenies. Only in case of ear length was the contrast between the two also significant. The mean value of most of the generations arising from the cross fell between the parental range.The three-parameter model failed to account for the variation in generation means in the case of days to heading. This character was concluded to be influenced by linkage and higher order interactions. For the other characters the three parameter model was adequate. For all characters, additive gene effects were most important as compared to dominance gene effects.The analysis of gene action as provided by the generation variance indicated that additive variance was much more pronounced as compared to dominance variance. The heritability was high for days to heading (71 per cent for narrow sense and 80 per cent in broad sense) and plant height (62 and 93 per cent in narrow and broad sense respectively.The implications of the results in breeding programmes have been discussed.     

The linear tetrasaccharide,Galβ1-4GlcNAcβ1-6Galβ1-4GlcNAc,isolated from radiolabeled teratocarcinoma poly-N-acetyllactosaminoglycan resists the action ofE. freundii endo-β-galactosidase

A novel linear tetrasaccharide, Gal1-4GlcNAc1-6Gal1-4GlcNAc, was isolated from partial acid hydrolysates of metabolically labeled poly-N-acetyllactosaminoglycans of murine teratocarcinoma cells. It was characterized by exo-glycosidase sequencing and by mild acid hydrolysis followed by identification of all partial cleavage products. The tetrasaccharide, and likewise labelled GlcNAc1-6Gal1-4GlcNAc, resisted the action of endo--galactosidase (EC 3.2.1.103) fromE. freundii at a concentration of 125 mU/ml, while the isomeric, radioactive teratocarcinoma saccharides Gal1-4GlcNAc1-3Gal1-4GlcNAc and GlcNAc1-3Gal1-4GlcNAc were cleaved in the expected manner.Abbreviations WGA wheat germ agglutinin - BSA bovine serum albumin - [³H]GlcNAc1-4-GlcNAc1-4GlcNAcOL N,N,NN'-triacetylchitotriose reduced with NaB³H₄