A general procedure for protoplast recovery,callus and plant regeneration in plants

A portion of this work was supported by NSF grant DCB 8718314 and by the Missouri Agricultural Experiment Station. This research is a joint contribution from the Missouri Agricultural Experiment Station, Journal Series No. 10,789 and from the Massachusetts Agricultural Experiment Station, Amherst, MA 01003; Journal Paper No. MAES 2959. Ousama Zaghmout was supported by the Food for the 21st Century Program, College of Agriculture, University of Missouri, Columbia, MO.     

Dependence of gibberellic acid-induced dark germination of lettuce seed on RNA synthesis

Summary Gibberellicacid-induced dark germination of Grand Rapids lettude seed was completely inhibited by 6-azauracil and partly by 2-thiouracil. Other inhibitors of nucleic acid and protein synthesis used were without effect. Inhibition of gibberellic acid-induced dark germination was reversed by uracil but not by thymine, deoxycytidine and orotic acid. The results suggest that gibberellic acid-induced dark germination is dependent on RNA synthesis and not on DNA synthesis.Gibberellic acid-induced lettuce hypocotyl growth was inhibited by all the inhibiters of nucleic acid and protein synthesis used, including actinomycin D, puromycin, chloramphenicol and p-fluorophenylalanine.Approved by the Director of the New York State Agricultural Experiment Station for publication as Journal Paper No. 1507.     

Copper as essential to wheat reproduction

Summary The role of Cu in promoting the reproductive phase of growth was examined using Thatcher spring wheat (Triticum aestivum L.). Plants were grown in limed Bladen soil (pH 5.3) in a controlled growth room. The plants were first harvested when five leaves had developed (day 23) and some top leaves of Cu-deficient (-Cu) plants had rolled (withertip) indicating a Cu deficiency. The leaves were shorter on Cu than Cu-sufficient (+Cu) plants, and fewer leaves developed. As they entered the reproductive growth phase, +Cu plants accumulated reducing sugars and reduced 2, 3, 5- triphenyltetrazolium chloride (TTC) in their stems, while Cu plants had lower concentration of the reducing sugars and very little TTC was reduced indicating a reduction in energy and in reducing capacity. Thin-layer-chromatography showed that top leaves of Cu plants contained higher concentrations of aspartic acid, alanine, and serine; and less aminobutyric acid than +Cu plants. Nitrate, P, and K concentrations were higher, and Ca and Cu were lower in Cu than in +Cu plants.Contribution of U.S. Department of Agriculture, Agricultural Research Service, Plant Stress Laboratory, Northeast Region, Beltsville, MD 20705 and North Central Region, Department of Agronomy, University of Nebraska, Lincoln, NE 68583 as Paper No.5187, Journal Series, Nebraska Agricultural Experiment Station.Contribution of U.S. Department of Agriculture, Agricultural Research Service, Plant Stress Laboratory, Northeast Region, Beltsville, MD 20705 and North Central Region, Department of Agronomy, University of Nebraska, Lincoln, NE 68583 as Paper No.5187, Journal Series, Nebraska Agricultural Experiment Station.     

Modification of amino acid and sugar transport in uncoupler-adaptedEuglena gracilis

Uncoupler-adaptedEuglena gracilis have a greatly impaired capacity to take up and incorporate some exogenously supplied amino acids and sugars. The degree of inhibition varies widely from >90% in the case of valine or glucose to none in the case of histidine. The inhibition is due to a decreased activity of the transport mechanism itself and is not due to either a lesion in the control mechanism for endogenous amino acid or sugar synthesis nor to a direct inhibition of the transport mechanism by uncouplers.No preferential labeling of mitochondrial membranes by [¹⁴C]amino acids occurs during the process of adaptation, a time when no cell division occurs. Apparently, during the long time required for adaptation, there occurs no major modification of mitochondrial proteins which could explain the subsequent resistance to uncouplers.Contribution from the Department of Biochemistry, School of Agriculture and Life Sciences and School of Physical and Mathematical Sciences. Paper No. 5179 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, North Carolina 27607.     

Mitochondrial biogenesis during fungal spore germination. Development of cytochrome c oxidase activity.

Mitochondria from dormant spores of the fungus Botryodiplodia theobromae did not contain extractable cyctochrome c oxidase (EC 1.9.3.1) activity; however, this enzyme activity was elaborated rapidly after 150 min of the 240-min germination sequence. The absence of cytochrome c oxidase activity in the dormant spores apparently is not an artifact caused by spore disruption and fractionation procedures, transient enzyme instability, or insensitivity of the enzyme assay. Mitochondria from dormant spores of three other phylogenetically diverse genera of fungi were observed to contain readily detectable quantities of cytochrome c oxidase, suggesting that the absence of the enzyme in B. theobromae may be relatively novel. The elaboration of cytochrome c oxidase activity in germinating spores was abolished by cycloheximide if the drug was added at or before 95 min of germination, but development of enzyme activity was initially insensitive to inhibitors of the mitochondrial genetic system, chloramphenicol or ethidium bromide. Incubation of spores in both ethionine and S-2-aminoethyl-l-cysteine reduced the amount of extracted cytochrome c oxidase activity. Elaboration of enzyme activity was severely retarded by cerulenin, an inhibitor of fatty acid biosynthesis and of spore germination. This enzyme activity developed in water-incubated or 1% Tween 80-incubated spores in which only the cytoplasmic ribosomes are functional in translation of a stored nuclear messenger RNA. The results of this study show that cytoplasmic (but not mitochondrial) ribosome function is required for development of this enzyme activity during spore germination, and they suggest that a portion of the cytochrome c oxidase enzyme or some other protein required for its activity is synthesized de novo upon germination.     

Effect of moisture and oxidation status of alkaline rice soils on the adsorption of soil phosphorus by an anion resin

Summary Considerable effort was devoted to experimentally explaining the greater amount of anion resin-adsorbable P (ARAP) in water-saturated alkaline soils relative to moist soils with the purpose of explaining the phenomenon of increased P availability in flooded rice soils. ARAP increased when waterlogged conditions were imposed on soils, but the increase in ARAP occurred before reducing conditions were obtained. Reducing conditions did not increase ARAP. The increase in ARAP in the water-saturated alkaline soils was attributed to the enhanced P diffusion resulting from a decrease in tortuosity, thus indicating that increased P availability upon flooding could be due to increased P diffusion.Paper number 4533 of the Journal Series of the North Carolina Agricultural Experiment Station.Paper number 4533 of the Journal Series of the North Carolina Agricultural Experiment Station.     

Nontarget effects of the herbicide tebuthiuron on mycorrhizal fungi in sagebrush semidesert

The effects of the herbicide tebuthiuron (0.36, 0.6, and 1.01 kg/ha in pellet form) on nontarget organisms, vesicular-arbuscular mycorrhizal fungi, were observed in sagebrush semidesert in central Utah. Only the highest level of tebuthiuron application showed any significant effects on mycorrhizal fungi compared to the untreated control. The introduced annual Bromus tectorum L. had both a reduced percent mycorrhizal root infection and reduced spore density in its rhizosphere with the highest herbicide level. The herbicide did not significantly affect mycorrhizal root infection of Sitanion hystrix, a short-lived perennial grass, at any level of application. There was no significant effect of any level of tebuthiuron on germination of mycorrhizal spores collected 6 months after herbicide application.Published with the approval of the Director, Utah Agricultural Experiment Station, as Journal Paper No. 3777     

Nutritional requirements and biochemical activities of pineapple pink disease bacterial strains from Hawaii

Bacteria which cause pink disease of pineapple, identified on the basis of their nutritional and biochemical activities, were found to belong to three genera. These bacteria include the following species: Gluconobacter oxydans, Acetobacter aceti, and Erwinia herbicola. Several pink disease strains required one to three vitamins for growth. Both G. oxydans strains 303D and 180 required biotin, nicotinic acid, and pantothenic acid for growth; E. herbicola 189 required only nicotinic acid; however, A. aceti 295 was able to grow without any added supplements in glucose mineral salts medium. Optimal vitamin concentrations for maximal growth and optimal pH for the maximal number of generations per hour was established for a few pink disease strains.Journal Series Paper No. 2373 of the Hawaii Agricultural Experiment Station, Honolulu.     

Characteristics of developing mitochondrial genetic and respiratory functions in germinating fungal spores

Spores of the fungus Botryodiplodia theobromae began a cyanide-sensitive oxygen consumption immediately upon exposure to a liquid medium, and spore germination and respiration were not affected by ethidium bromide, d-threochloramphenicol, and acriflavin until later during germ tube emergence. These inhibitors of the mitochondrial genetic system all inhibited total cell protein synthesis to the same intermediate degree from the outset of incubation. When spores were incubated in water under non-germinating conditions, protein synthesis and oxygen uptake proceeded at initial rates almost identical to those seen in spores germinating in the presence of the three mitochondrial system inhibitors. Although the spores respired at rapid rates from the onset of incubation, no cytochrome absorption peaks could be observed in mitochondrial fractions prepared from ungerminated spores; they were readily observed in germinated spores, however. When the spores were germinated in the presence of inhibitors of the mitochondrial system, an excess of cytochrome c was observed in the near absence of cytochromes a and b. The results indicate that the ungerminated spores of this organism contain a preserved, potentially functional aerobic respiratory system which requires cycloheximide-sensitive ribosome activity to become functional when the spores are inoculated into a liquid medium.     

DNA content of Phaseolus coccineus x P. vulgaris suspensors

Summary At the globular stage of embryo development, the level of DNA, as determined from microspectrophotometric analysis of Feulgen-stained squashes, was significantly higher in the interspecific hybrid suspensor than in suspensors from self-pollination of Phaseolus coccineus, the maternal parent. However, at the early-heart and early-cotyledonary stages of development, DNA content of interspecific hybrid suspensors was significantly lower than that of suspensors formed after self-pollination of either P. coccineus or P. vulgaris. The relationship between DNA content and suspensor cell length for P. coccineus and P. vulgaris at all developmental stages and between DNA content and cell area for P. coccineus at the early-cotyledonary stage was altered in hybrid suspensor cells. Nuclei in large cells of interspecific suspensors exhibited uneven distribution of polytene chromosomes and no clear nuclear outline.Paper number 18,470 of the Scientific Journal Series, University of Minnsota Agricultural Experiment Station, St. Paul, MN. This research was funded by the USDA CRGO under grant number USDA-85-CRCR-1-1676     

Sporophytic recognition of pollen S alleles in the gametophytic self-incompatibility system of Nemesia strumosa benth

Summary Several seedlings of Nemesia strumosa with various levels of pseudo-self-compatibility (PSC) often produced more seed after self pollination than when pollinated using pollen from incompatible plants bearing the same S alleles. Sporophytic recognition of self pollen apparently increases PSC levels above those attributable to modifying genes which interfere with normal stylar activity.Scientific Journal Series Paper Number 9546 of the Minnesota Agricultural Experiment Station.     

Plasmid-like DNAs associated with mitochondria of cytoplasmic male-sterile Sorghum

Summary Plasmid-like, linear DNAs were detected in preparations of mitochondrial DNA from cytoplasmic male-sterile sorghum. Designated N-1 and N-2, the DNAs exhibited molecular sizes of ca. 5,700 and 5,300 bp, respectively. The DNAs occurred in only the IS1112C entry among 24 entries examined. Electron microscopy of the DNAs indicated that the molecules were linear as isolated. Nick translation of N-1 and N-2 followed by membrane hybridization indicated substantial homology between the two DNAs, and some homology to the S-1 and S-2 maize plasmid-like DNAs. At least four additional DNA species, ranging from ca. 1,000–4,000 bp if linear, were also detected in sorghum mitochondrial DNA. The detection of plasmid-like DNAs in sorghum, with homology to the plasmid-like DNAs of maize, suggests an etiological relationship of the molecules to the inheritance and expression of cytoplasmic male sterility in sorghum, perhaps in a manner analogous to the postulated role of these elements in maize.Cooperative Investigations of Agricultural Research Service, U.S. Department of Agriculture, Institute of Food and Agricultural Sciences, University of Florida, Texas Agricultural Experiment Station, and Department of Genetics, North Carolina State University. Florida Experiment Stations Journal Series No. 3578     

Opposing effects of strychnine and brucine on the germination and growth of lettuce seeds

Strychnine and brucine, two related alkaloids that occur in plants belonging to theStrychnos species, were shown to have opposing effects on the elongation of the radicle of lettuce seeds. Strychnine was found to be inhibitory, whereas brucine was found to be stimulating to radicle elongation. Alkaloids, generally, are more commonly known for their inhibitory effects on plant growth rather than on their stimulating effects.Paper No. 2435 of the Journal Series of the South Dakota Agricultural Experiment Station, Brookings, South Dakota, USA.     

Isozyme variability in species of the genus Drosophila. VII. Genotype-environment relationships in populations of D. melanogaster from the eastern United States

Collections of D. melanogaster were analyzed for genetic variation at nine enzyme loci. Allelic frequencies were determined, and comparisons between observed phenotypic proportions and those expected under equilibrium conditions were made. A significant tendency toward homozygote excess was noted. Relationships between patterns of genetic variability and between patterns of genetic and environmental variability were examined by the method of principal components and correlation analysis. Several of the loci showed a clinal pattern in gene frequencies, and overall there was an appreciable amount of genetic-genetic and genetic-environmental association.This work was supported by PHS Research Grant No. GM 11546 and AEC Contract No. AT-(40-1)-3980. Paper No. 4026 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, North Carolina.     

Patulin effects on wheat plants in field treatments

Summary Fall field patulin applications (500 µg/g of soil) to Cheyenne winter wheat seedlings at growth stages 0, 1, and 2, decreased germination, plant growth, winter survival, and tillering. Decreased tillering decreased the number of heads and grain yield. Spring patulin application of 250 and 500 µg/g of soil to wheat at growth stages 6, 7, 8, 9, and 10 decreased yields by decreasing the number of heads, kernels per head, and kernel weight. With fall patulin applications, yields were decreased more when patulin was applied near seeding. Spring patulin applications to wheat during sensitive heading stages decreased yield the most.Stages of wheat growth especially susceptible to patulin are the germination, stem-elongation, and flowering, which occur during the fall and spring when soil Penicillium urticae Bainier numbers are maximun and patulin has been extracted from the soil.Contribution from the Soil, Water, and Animal Waste Management Research Unit, North Central Region, Agricultural Research Service, U.S. Department of Agriculture, in cooperation with the Nebraska Agricultural Experiment Station, Lincoln. Published as Paper No. 4071, Journal Series, Nebraska Agricultural Experiment Station.Microbiologist, USDA, A.R.S. University of Nebraska, Lincoln; Soil Scientist, USDA, A.R.S. Fort Collins, Colorado; and Microbiologist, USDA, A.R.S. University of Nebraska, Lincoln, respectively.     

Order of the ilv genes of Salmonella montevideo

Summary Ilv mutants of aSalmonella typhimurium-Salmonella montevideo hybrid were used in cotransduction studies to obtain evidence for the order of theilv genes ofS. montevideo. The following order, which is the same as that previously reported forS. typhimurium, is derived:ilvE-ilvD-ilvA-ilvC.From the Departments of Genetics and Biochemistry, School of Agriculture and Life Sciences, and School of Physical and Mathematical Sciences, North Carolina State University, Raleigh, North Carolina 27607. Paper No. 3300 of the Journal Series of the North Carolina State University Agricultural Experiment Station, Raleigh, North Carolina. Supported by Research Grant GM 14184-04 from the Public Health Service.     

Characteristics of ribonucleic acids isolated from Botryodiplodia theobromae pycnidiospores

Nucleic acids isolated from dormant and germinated Botryodiplodia theobromae pycnidiospores contain five distinct species of RNA. They include two ribosomal species, two ribosomal-associated species and transfer RNAs. Sedimentation coefficients of 25.1S and 18S were obtained for the two ribosomal RNA species and 5.8S and 5S for the two ribosomal-associated RNA components. Molecular weights of 1.20, 0.67, 0.054 and 0.035x10⁶ daltons were obtained after formaldehyde treatment and electrophoresis on polyacrylamide gels for these same four RNAs. Methylated nucleotides were present in the transfer RNAs and large and small ribosomal RNAs; in contrast 5.8S and 5S RNAs contained few methylated nucleotides. In addition to the 5 distinct RNA species, polyadenylate-containing RNA was isolated from both dormant and germinated spores.Published with the approval of the Director as paper no. 5006, Journal Series, Nebraska Agricultural Experiment Station. The work was conducted under Nebraska Agricultural Experiment Station Project no. 21-17.     

Growth characteristics of a continuous cell line from the velvetbean caterpillar,Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae)

Summary The cell line UFL-AG-286 was established from the embryos ofAnticarsia gemmatalis (Lepidoptera: Noctuidae). The cell line was characterized by isozyme analysis and from molecular weight determination of the restriction endonuclease bands of the mitochondrial DNA. Cells seeded in 24-cluster wells had a doubling time of 5.9 d when seeded at 2×10⁵ cells ml and 6.7 d when seeded at 3×10⁵ cells/ml. This work was funded by U.S. Department of Agriculture grant 84-CRCR-1-1431. Florida Agricultural Experiment Station Journal Series, no. 8181.     

Associative nitrogenase activity by some Hawaiian grass roots

Summary Nitrogenase activity by the roots of some tropical grasses was detected by the acetylene reduction technique. In some cases particular plant species, evaluated at different times from different sites, displayed marked variations in nitrogenase activity.Acetylene reduction by root samples which had undergone preincubation under low O₂ displayed an increase of approximately 5-fold when compared to plant-containing soil cores. These increases in nitrogenase activity correspond to an increase in the number of nitrogen-fixing bacteria associated with the roots.Journal Series No. 2066 of the Hawaii Agricultural Experiment Station, Honolulu, Hawaii 96822Journal Series No. 2066 of the Hawaii Agricultural Experiment Station, Honolulu, Hawaii 96822     

Gene dosage at the amylose-extender locus of maize: Effects on the levels of starch branching enzymes

Soluble starch branching enzymes and starch synthases from maize kernels of differing dosage of the ae locus were purified by DEAE-cellulose chromatography. A near-linear relationship between increasing dosage of the dominate amylose-extender allele (Ae) and branching enzyme IIb activity was found. In contrast, levels and properties of branching enzymes I and IIa, as well as the citrate-stimulated and primer-requiring starch synthases, remained unchanged. The near-linear increase in branching enzyme IIb activity with increasing doses of the Ae allele is consistent with the hypothesis that ae is the structural gene coding for branching enzyme IIb.Paper of the Journal Series, New Jersey Agricultural Experiment Station, Cook College, Rutgers University, New Brunswick. This work was performed as part of NJAES Projects 12442 and 12201 (NE-124), supported by the New Jersey Agricultural Experiment Station, Regional Research Funds, NSF Grant PCM 78-16127, and funds from Corn Refiners Association, Inc.