Experimental evaluation of the foliar flag hypothesis using fruits of Rhus glabra (L.)

I tested experimentally whether the presence of colorful plastic ovals (simulating foliar flags) attached to infructescences of Rhus glabra increase fruit removal by birds in a forest-oldfield border. I used a factorial experimental design testing for the effect of size (small or large) and color (yellow or red) of the flags. There was also a control, without flags. Large red flags increased the percent of fruits removed from the panicles, but yellow and small flags had no effect. My results give partial support to Stiles (1982) hypothesis that early color change of leaves close to the fruits in some plants may serve as visual signals that attract frugivorous birds and enhances seed dispersal.     

Agronomic and chemical evaluation of selected sorghums as sources of pulp

Nine accessions representing three sorghum species were grown at six locations in a single crop year to evaluate their potential as fibrous raw materials for pulp and papermaking. Evaluations were based on field yields, agronomic characteristics, and physical and chemical composition. Growing conditions caused considerable variation, but maturity, time of harvest, and harvesting methods also influenced composition. Preferred locations based on production of whole stalks (exclusive of roots) and of culms were Iowa, Indiana, and Georgia. The best productivity for several accessions exceeded 10 tons per acre (o.d.) for whole stalks and 6 tons per acre for culms. The mean content (for three locations) of crude cellulose in culms, ranged from 40.9 to 53.8% and of alpha cellulose from 25. 7 to 34. 7%; the level of pith ranged from 6.1 to 15.2%. Ash content in culms was 3% or less compared with 7% or more in leaves. Late-maturing PI 22983 7 and 229847 were consistently good yielders, but were chemically inferior to PI 177549 and 190579. Composition of PI 177549 was the most favorable, with a high proportion of culms to leaves and with crude cellulose content of 58.4% in culms (Georgia). In Iowa, the content of crude cellulose in culms of PI 229837 was equivalent to 3.40 tons per acre, and that of alpha cellulose was equivalent to 2.31 tons per acre. Accessions meriting further consideration are: PI 177549 (broom corn), 229837 and 229847 (kafir types), and 190579 (sorghum grass).     

Agronomic,genetic and chemical tools for hop cultivation and breeding

Phytochemistry Reviews - Humulus lupulus L. (hop) is a dioecious climbing plant of which the females bear particular inflorescences, called hops, ‘cones’ or ‘strobiles’,...     

Agronomic evaluation of tissue-culture-derived soybean plants

Summary Genetic alterations of regenerated plants based on the tissue culture process (somaclonal variation) have become common for many plant species including soybean [Glycine max (L.) Merr.]. The objective of this study was to test for the presence of tissue-culture-derived genetic variation in eight agronomic traits in homozygous progeny regenerated by organogenesis using the commercially important cultivar Asgrow A3127. A total of 86 lines derived by repeated self-pollination of nine regenerated plants was grown in two locations for 2 years. When compared to the unregenerated parent, statistically significant variation (P<0.05) was found for maturity, lodging, height, seed protein and oil, but not for seed quality, seed weight, or seed yield. All of the variation noted was beneficial and did not involve decreased yield. Since the differences were not large, the results indicate that the tissue culture process is not necessarily detrimental to plant performance, which is an important consideration since tissue culture techniques are used in many genetic engineering methods.     

Comparative morphology and physiology of fruit and seed development in the two shrubs Rhus aromatica and R. glabra (Anacardiaceae)

Morphology and physiology of fruit and seed development were compared in Rhus aromatica and R. glabra (Anacardiaceae), both of which produce drupes with water-impermeable endocarps. Phenology of flowering/fruiting of the two species at the study site was separated by ∼2 mo. However, they were similar in the timetable and pattern of fruit and seed development; it took ∼2 mo and ∼1.5 mo for flowers of Rhus aromatica and R. glabra, respectively, to develop into mature drupes. The single sigmoidal growth curve for increase in fruit size and in dry mass of these two species differs from the double-sigmoidal one described for typical commercial drupes such as peach and plum. Order of attainment of maximum size was fruit and endocarp (same time), seed coat, and embryo. By the time fruits turned red, the embryo had reached full size and become germinable; moisture content of seed plus endocarp had decreased to ∼40%. The endocarp was the last fruit component to reach physiological maturity, which coincided with development of its impermeability and a seed plus endocarp moisture content of <10%. At this time, ∼50, 37, and 13% of the dry mass of the drupe was allocated to the exocarp plus mesocarp unit, endocarp, and seed, respectively. The time course of fruit and seed development in these two species is much faster than that reported for other Anacardiaceae, including Rhus lancea, Protorhus, and Pistacia.     

Stabilization of erythrocytes against oxidative and hypotonic stress by tannins isolated from sumac leaves (Rhus typhina L.) and grape seeds (Vitis vinifera L.)

Erythrocytes are constantly exposed to ROS due to their function in the organism. High tension of oxygen, presence of hemoglobin iron and high concentration of polyunsaturated fatty acids in membrane make erythrocytes especially susceptible to oxidative stress. A comparison of the antioxidant activities of polyphenol-rich plant extracts containing hydrolysable tannins from sumac leaves (Rhus typhina L.) and condensed tannins from grape seeds (Vitis vinifera L.) showed that at the 5-50 μg/ml concentration range they reduced to the same extent hemolysis and glutathione, lipid and hemoglobin oxidation induced by erythrocyte treatment with 400 μM ONOO(-) or 1 mM HClO. However, extract (condensed tannins) from grape seeds in comparison with extract (hydrolysable tannins) from sumac leaves stabilized erythrocytes in hypotonic NaCl solutions weakly. Our data indicate that both hydrolysable and condensed tannins significantly decrease the fluidity of the surface of erythrocyte membranes but the effect of hydrolysable ones was more profound. In conclusion, our results indicate that extracts from sumac leaves (hydrolysable tannins) and grape seeds (condensed tannins) are very effective protectors against oxidative damage in erythrocytes.     

Agronomic evaluation of prospective new crop species

Preliminary field evaluations for 162 species are reported. This work represents a portion of a team-oriented effort to develop new crops for American agriculture. These species are potential new oilseed sources of epoxy, crepenynic, erucic, and other fatty acids, and sources of seed gum, steroids, and pulp. Euphorbia lagascae andCephalaria setosa show the most promise for crop development as epoxy acid sources, but both require substantial improvement through breeding.Crepis alpina, a small-seeded species with excellent seed retention, is the best prospect for providing an oil rich in crepenynic acid. A selection and breeding program is under way. None of the species tested as erucic acid sources equalled the crop potential of crambe and selected Brassicas.Briza spicata, a small, moderately productive grass, is the richest known source of glycolipids.B. spicata has been grown successfully as a winter annual at several locations. Earlier maturity and better seedling vigor is needed inSatureja hortensis, a source of oil similar to linseed oil.Xeranthemum annuum, an attractive, winter annual and everlasting, is very good agronomically, but the use of the oil with its mixture of several fatty acids is not economically favorable.Solanum khasianum shows agronomic promise as a source of the steroid, solasodine.Cassia occidentalis, C. bonariensis, Crotalaria leioloba, andC. stipularia are productive potential seed gum sources. These species, especiallyCassia occidentalis, seem to be sufficiently good agronomically to justify intensive breeding. Of the various sources of pulp, emphasis is on kenaf because highyielding, well-adapted varieties are available.Crotalaria juncea merits breeding effort, and other species show sufficient promise for further evaluation.     

Identification of a mutagenic substance in a spice, sumac, as quercetin.

The mutagenicity of a spice, sumac, was demonstrated on Salmonella typhimurium strain TA98. The active principle was purified and characterized by thin-layer chromatography, UV-absorption spectroscopy and mass spectrometry. All the mutagenic activity of sumac was found to be due to quercetin.     

N,N-dimethylsphingosine-coumarin: synthesis, chemical characterization, and biological evaluation

Coumarin derivatives of N,N-dimethylsphingosine (DMSP) were prepared and chemically characterized. They were apparently biologically equivalent to DMSP in terms of tumor cell cytotoxicity and were used to establish the rapid mitochondrial localization of this sphingolipid in tumor cells, followed closely by its marked reduction of mitochondrial membrane potential.     

Juvenile Rhus glabra leaves have higher temperatures and lower gas exchange rates than mature leaves when compared in the field during periods of high irradiance

We sought to test the hypothesis that stomatal development determines the timing of gas exchange competency, which then influences leaf temperature through transpirationally driven leaf cooling. To test this idea, daily patterns of gas exchange and leaflet temperature were obtained from leaves of two distinctively different developmental stages of smooth sumac (Rhus glabra) grown in its native habitat. Juvenile and mature leaves were also sampled for ultrastructural studies of stomatal development. When plants were sampled in May-June, the hypothesis was supported: juvenile leaflets were (for part of the day) from 1.4 to 6.0 degrees C warmer than mature leaflets and as much as 2.0 degrees C above ambient air temperature with lower stomatal conductance and photosynthetic rates than mature leaflets. When measurements were taken from July to October, no significant differences were observed, although mature leaflet gas exchange rates declined to the levels of the juvenile leaves. The gas exchange data were supported by the observations that juvenile leaves had approximately half the number of functional stomata on a leaf surface area basis as did mature leaves. It was concluded that leaf temperature and stage of leaf development in sumac are strongly linked with the higher surface temperatures observed in juvenile leaflets in the early spring possibly being involved in promoting photosynthesis and leaf expansion when air temperatures are cooler.     

The regulation of inflammatory cytokine secretion in macrophage cell line by the chemical constituents of Rhus sylvestris

In our preliminary screening study on the anti-inflammatory activity, eight triterpenes, one sterol, and one chalcone were isolated from the CH₂Cl₂-soluble extract of the stems and leaves of Rhus sylvestris Siebold and Zucc (Anacardiaceae). On the basis of their spectroscopic data, these compounds were identified as 10α-cucurbitadienol (1), glut-5-en-3-ol (2), β-amyrin acetate (3), β-amyrin (4) and lupeol (5), cycloart-24-en-3-one (6), cycloart-25-en-3,24-dione (7), 24-hydroxycycloart-25-en-3-one (8), β-sitosterol (9), and 2′-hydroxy-4,4′-dimethoxychalcone (10). All of them were isolated from this plant for the first. Furthermore, the compounds in non-cytotoxic concentrations (0–1.0 μM) were tested for their ability to block inflammatory cytokine secretion in the presence of LPS in the murine RAW264.7 macrophage cell line. Among the compounds that were tested, compounds 8 and 9 reduced the LPS-induced secretion of IL-6, as well as TNF-α, in a mouse RAW264.7 macrophage cell line. Moreover, compounds 2, 3, 7, and 10 specifically diminished only the secretion of TNF-α even in 0.01 μM concentrations. It is thus suggested that they are potential therapeutics of TNF-α-related diseases and conditions, such as transplant rejection, type II diabetes, and atherosclerosis.     

Agronomic evaluation of inbred lines derived from tissue cultures of maize

Summary Tissue culture-induced variation has been proposed as a novel source of variation for crop improvement. In maize (Zea mays L.), chromosome aberrations and qualitative genetic variants have been induced during in vitro culture. The proportion of regenerated plants carrying such variants has been shown to increase with culture age. The objective of this research was to evaluate the relationship between culture age and somaclonal variation for several agronomic traits. Six sib-pollinated ears of S₀ (F₂) plants in four OH43 ms/A188 populations each provided control seed and embryos for culture initiation. S₂ lines derived from control seed and from plants regenerated 4 and 8 months after culture initiation were grouped according to their source ear and grown in 6 separate trials. A total of 305 tissue culture-derived and 48 control lines were evaluated as lines per se and in a testcross at each of three locations. Tissue culturederived lines and their testcrosses generally had lower grain yield and moisture. Since grain yield and moisture were not positively correlated in any trial, the highest yielding lines could be selected without increasing grain moisture. Grain yield and plant height tended to decrease with culture age. Although tissue culture-derived lines were, on average, inferior, the highest yielding line per se in three of six trials and the top-ranked line in five of six trials for yield and moisture were derived from tissue culture. The results indicate that tissue culture may generate variation for agronomic traits. Some of the variation, particularly the trend towards earlier maturity, could be useful. However, this method may require screening large populations because of the tendency to generate a large proportion of inferior lines.Contribution from Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108. Minnesota Agric. Exp. Stn. Scientific Journal Series Paper No. 15,172     

Agronomic evaluation of prospective mnew crop species II. The AmericanLimnanthes

Limnanthes is a potential seed oil source of long chain fatty acids. Agronomic evaluations in Alaska, California, Maryland, and Oregon indicate that theL. alba group has the best crop potential because of superior seed retention and erect growth habit. Experimental seed yields of 1700 kg/ha or more indicate that economically feasible yields on a commercial scale will be attainable, as continued study reveals optimum cultural practices and utilizes variability present in the various accessions. For the best seed yields,Limnanthes must be handled as a winter annual in California, Maryland, and Oregon but as a spring-seeded annual in Alaska.Limnanthes plants mature rapidly during hot weather; thus the timing of harvest is critical for maximization of seed yields. Further studies on seeding rates, weed control, and harvest methods are suggested.     

31P NMR spectroscopy, chemical analysis, and free Mg2+ of rabbit bladder and uterine smooth muscle

31P NMR spectra of isolated rabbit bladder and uterus were obtained under steady-state arterial perfusion in vitro at rest and while stimulated. The spectra contained seven major peaks: phosphoethanolamine, sn-glycero(3)phosphocholine, inorganic phosphate (Pi), phosphocreatine, and the gamma, alpha, and beta peaks of ATP. Chemical analyses, high-pressure liquid chromatography, and NMR spectroscopy of aqueous extracts of bladders identified a number of other components that also made contributions to, but were not resolved in, the spectra of the intact tissues: UTP, GTP, UDP-Glc, NAD+, phosphocholine, and sn-glycero(3)phosphoethanolamine. Intracellular pH of unstimulated bladders and uteri, measured from the chemical shift of the Pi peak, was 7.10 +/- 0.09 S.D. and 7.01 +/- 0.12 S.D., respectively. The chemical shift of the beta-ATP peak in the smooth muscles was significantly upfield (-0.3 ppm) compared to the chemical shift observed in striated muscles (cat biceps and rat myocardium). An ADP peak was identified in stimulated and ischemic bladders. The chemical shifts of the nucleotides observed in perfused bladders were calibrated as a function of free Mg2+ concentration in solutions containing phosphocreatine, Pi, ADP, and ATP at an ionic strength of 180 mM. We derived the following estimates for the intracellular free Mg2+ concentration: uterus, 0.40 mM; unstimulated bladder, 0.46 mM; stimulated and ischemic bladder, 0.50 mM (from the ATP chemical shift) and 0.45 (from the ADP chemical shift); cat biceps, 1.5 mM; and rat myocardium, 1.4 mM.     

Two bioactive mono-tetrahydrofuran acetogenins, annoglacins A and B, from Annona glabra

Two new bioactive mono-THF Annonaceous acetogenins, annoglacins A and B, have been isolated from the fractionated ethanolic extracts of the leaves of Annona glabra, directing the fractionation with the brine shrimp lethality test (BST). Their structures were elucidated based on spectroscopic and chemical methods and the absolute stereochemistries were determined by the advanced Mosher ester method. Annoglacins A and B were selectively 1000 and 10,000 times, respectively, more potent than adriamycin against the human breast carcinoma (MCF-7) and pancreatic carcinoma (PACA-2) cell lines in our panel of six human solid tumor cell lines.     

Cloning,expression and purification of an ascorbate peroxidase gene from Rhus chinensis

Journal of Plant Biochemistry and Biotechnology - The sumac species Rhus chinensis is widely used in traditional Chinese medicine. APX is the key enzyme in hydrogen peroxide degradation, and may...     

火炬树的组织培养及植株再生

植物名称　火炬树 (Ｒｈｕｓｔｙｐｈｉｎａ)。2　材料类别　茎尖。3　培养条件　培养基 :( 1 )ＭＳ 6 ＢＡ 2 .0ｍｇ·Ｌ-1(单位下同 ) ;( 2 )ＭＳ 6 ＢＡ 1 .0 ＮＡＡ 0 .1 ;( 3)ＭＳ。以上培养基均加蔗糖 30ｇ·Ｌ-1、琼脂 7ｇ·Ｌ-1,ｐＨ 6～ 6 .5 ;培养温度白天 2 5～ 30℃ ,夜间 1 5～ 2 0℃ ;光照时间 1 2ｈ·ｄ-1,光照度 2 0 0 0～ 2 5 0 0ｌｘ。4　生长与分化情况4.1　芽的分化　剪取健壮的枝条 ,先将枝条切成小段 ,每段带一个芽 ,在无菌条件下 ,将切段浸入 70 %酒精中 ,经数秒钟 ,再用 0 .1 %升汞溶液浸泡 8ｍｉｎ ,然后…