bluuebunny/crossref_metadata_2025_split huggingface dataset:
EFFECTS OF N‐(1,1‐DIMETHYLPROPYNYL)‐3,5‐ DICHLOROBENZAMIDE ON THE ANATOMY OF AGROPYRON REPENS (L.) BEAUV.
Authors: PETERSON R. L. , SMITH L. W. 
Published: July 2006

Summary. .Plants of Agropyron repens (L.) Beauv. which bad been sprayed with N‐(1,1‐dimethylpropynyl)‐3,5‐dichlorobenzamide (pronamide) were examined for changes in external and internal morphology at various times after spraying. Cell enlargement, some necrosis, and an increase in nuclear volume characterized treated rhizome apices. Abnormal metaxylem vessel elements and necrotic phloem were characteristic of the rhizome vascular tissues. Roots showed precocious differentiation and maturation of tissues and eventual vacuolation of the apical maeristem, resulting in complete inhibition of root growth. Nuclei of root meristem cells were much enlarged and contained several nucleoli. Effets du N‐(1,1‐diméthylpropynyl)‐3,5‐dichlorobenzamide sur l'anatomie de l' Agroyron repens (L.) Beauv.
DEGRADATION OF FLUORODIFEN‐1′‐14C BY PEANUT SEEDLING ROOTS
Authors: EASTIN E. F. 
Published: July 2006

Summary. Degradation of p‐nitrophenyl‐α,α,α:‐trifluoro‐2‐nitro‐p‐tolyl ether (fluorodifen) labelled with 14C in the 1 position of the p‐nitrophenyl ring (1′‐14C) proceeded rapidly in peanut (Arachis hypogaea L. cv. Starr) seedling roots. All degradation products were present after only 2 h.The major degradation products for fluorodifen‐1′‐14C were the water‐soluble compounds p‐nitrophenol and Unknown I, a polar compound or complex which remained on the origin during thin‐layer chromatography. Minor products included p‐nitrophenyl‐α,α,α‐trifluoro‐2‐amino‐p‐tolyl ether, p‐aminophenyl‐α,α,α‐trifluoro‐2‐nitro‐p‐tolyl ether and traces of p‐aminophenol. No p‐aminophenyl‐α,α,α‐trinuoro‐2‐amino‐p‐tolyl ether was detected. The p‐aminophenol previously reported [PL Physiol., Lancaster, 44,1397‐1401 (1969)] was not p‐aminophenol, but primarily Unknown I with a possible trace of p‐aminophenol.Fluorodifen continued to be absorbed throughout the 72‐h treatment period.
EFFECTS OF LIGHT INTENSITY, PHOTOPERIOD AND NITROGEN ON THE GROWTH OF SEEDLINGS OF AGROPYRON REPENS (L.) BEAUV. AND AGROSTIS GIGANTEA ROTH
Authors: WILLIAMS E. D. 
Published: July 2006

Summary. Seeding of Agropyron repens (L.) Beauv. und Agrostis gigantea Roth were grown in two photoperiods and with amounts of nitrogen. On two occasions plants transferred between photoperiods.The early growth of the seedlings was increased most by increasing the light intensity, but later nitrogen had the greatest effect. In short photoperiods, plants of both species were decumbent and had many more shoots than in long photoperiods. At the end of the experiment, plants of both species responded more to nitrogen in bright than in dim light, and the dry weight of Agropyron was increased more than that of Agrostis by increased photoperiod and nitrogen. Agropyron initiated rhizomes sooner than Agrostis; it had fewer rhizomes but they were longer and thicker and weighed more. Brighter light, longer photoperiod and nitrogen all increased rhizome weight. Photoperiod did this mainly by producing more rhizomes, light by increasing thickness or density, and nitrogen by both. The effects of photoperiod and nitrogen on the rhizome dry weight of Agropyron, but not of Agrostis, were additive.Transferring plants from short to long photoperiods or from long to short, respectively increased or decreased total growth, but had an opposite effect on the rhizomes.
DEGRADATION OF BROMOXYNIL IN REGINA HEAVY CLAY*
Authors: SMITH ALLAN E. 
Published: July 2006

SummaryA spectrophotometric method was developed to detect bromoxynil in Regina heavy clay, and the breakdown under different temperature and moisture conditions was studied. At rates equivalent to 14 kg/ha, over 50% of the applied bromoxynil was degraded in 2 weeks at 25°C and at moisture levels in excess of the wilting point. Losses at 18°C were slightly slower. Little breakdown occurred in sterile soil, indicating that microbial degradation could be an important factor contributing to bromoxynil breakdown under field conditions.Paper and thin‐layer chromatographic techniques were used to isolate and identify soil degradation products. In addition to the parent compound small amounts of 3,5‐dibromo‐4‐hydroxybenzamide and 3,5‐dibromo‐4‐hydroxybenzoic acid were detected.
REGENERATIVE CAPACITY OF ROOT FRAGMENTS OF CIRSIUM ARVENSE (L.) SCOP.
Authors: HAMDOUN A. M. 
Published: July 2006

Summary. Root fragments less than 5 mm long were unable to form shoots. However, shoots were produced by fragments 10 mm long and 1 mm in diameter, unless originating from immature apical regions. The number of shoots per unit length of root was greater if the root was cut into many small pieces than into a few long ones. The ability to produce shoots was apparently unrelated to the presence or absence of visible buds.Root fragments showed polarity; most of the shoots originated from the basal (proximal) end and the roots from the apical (distal) end. Soil moisture content had relatively little effect upon growth from a fragment unless the soil was waterlogged or very dry for prolonged periods. Growth from fragments was prevented by temperatures below 5°C; optimum growth occurred at 15°G. Shoots from fragments 25 mm long emerged successfully from depths of 50 cm. Capacité de régenération de fragments de racines de Cirsium arvense (L.) Scop.
A SPLIT‐ROOT TETRAZOLIUM METHOD FOR EVALUATING EFFECTIVENESS AND PHYTOTOXICITY OF ROOT‐ACTIVE HERBICIDES
Authors: DUFFY SPENCER L. 
Published: July 2006

Summary. Copper sulphate (GUSO4.5H2O) and sodium hydroxide (NaOH) were used to test the performance of a split‐root method for evaluating the effectiveness and phytotoxicity of root‐active herbicides. This method involves a vertical separation of the root system of weeping willow (Salix babylonica L.) cuttings. One section is treated with the herbicide dissolved in half‐strength Hewitt's medium while the other remains in medium without herbicide during the test period. Roots are assayed with 2,3,5‐triphenyttetra‐zolium chloride 24 h after treatment to determine their viability. Both herbicides satisfactorily reduced the viability of the treated roots as measured by the quantity of formazan extracted. Copper sulphate was systemic and injured untreated plant parts; sodium hydroxide affected only treated roots. The split‐root tetrazolium method is relatively rapid and does not require sophisticated laboratory equipment.Méthode au tétrazolium sur portions de racines pour l'évaluation de l'efficacité et de la phytotoxicité des herbicides agissant par les racines
BEKÄMPFUNG VON GALIUM APARINE MIT MECOPROP IN ABHÄNGIGKEIT VON VERSCHIEDENEN BODENARTEN
Authors: SCHMIDT ROBERT R. 
Published: July 2006

Zusammenfassung. Die Bekämpfung von Galium aparine L. mit Mecoprop im Nachauflaufverfahren ist abhangig sowohl von der Pflanzengrösse ab auch vor allem vom Boden, in dem die Pflanzen wachsen:

Kleine Pflanzen werden leichter vernichtet als grosse.
Pflanzen, die auf einem Boden mit hohem organischen Anteil wachsen, sind gegen Mecoprop widerstandsfähiger als solche, die auf einem Boden mit niedrigem C‐Gehalt wachsen.
Ein Teil der im Nachauflaufverfahren gespritzten Herbizidmenge gelangt auf den Boden und wirkt zusätzlich durch Aufnahme über die Wurzeln.
Diese zusätzlichc herbizide Wirkung ist auf den Bodenproben I und II mit hohem organischen Anteil geringer als auf dem Boden mit niedrigem C‐Gehalt. Als Ursache der geringeren Wirksamkeit ist eine verstärkte Adsorption des Mecoprop in den Bodenproben I und II gegenüber Boden III verantwortlich.
Als Adsorbens kommt nur die organlsche Substanz der Bodenproben in Frage.

Der zu erzielende Gesamtbekämpfungserfolg hängt neben der Aufnahme des Mecoprop über das Blatt auch von der zusätzlichen Wirkung des Herbizids über den Boden ab. Control of Galium aparine with mecoprop in relation to soil type
MORPHOLOGICAL, ANATOMICAL AND BIOCHEMICAL EFFECTS OF PROPACHLOR ON SEEDLING GROWTH*
Authors: DHILLON NIRMAL S. , ANDERSON J. LaMAR 
Published: July 2006

Summary. The root and shoot growth of oat (Avena saliva L.) and squash (Cucurbita maxima Duchesne) was reduced in proportion to propachlor concentration. Corn (Zea mays L.) root growth was inhibited only by concentrations of 16 ppm and higher. Cell division in onion (Allium cepa L.) root tips was reduced by propachlor and totally inhibited by 16 ppm. Auxin‐induced cell elongation of oat coleoptiles was inhibited in proportion to propachlor concentration. Propachlor treatment prevented the normal senescence of squash cotyledons by inhibiting the autolysis of proteinaceous and lipid reserves.Effets morphologiques, anatomiques et biochimiques du propachlore sur la croissance des plantules Riisumi.
THE EFFECT OF CHLORMEQUAT SEED‐PARENT TREATMENT ON THE RESISTANCE OF WHEAT SEEDLINGS TO TERBUTRYNE AND SIMAZINE
Authors: PINTHUS MOSHE J. 
Published: July 2006

Summary. The effects of pre‐sowing treatments with terbutryne (4‐ethylamino‐2‐ niethylthio‐6‐t‐butylamino‐1,3,5‐triazine) and with simazine (2‐chloro‐4,6‐bisethyl‐amino‐1,3,5‐triazine) on seedling mortality of wheat grown from regular seed and from seed containing about 40 ppm chlormequat (2‐chloroethyl trimethylammonium chloride), due to a late chlormequat treatment of the seed‐parent, were tested in two pot experiments. In another pot experiment the effects of pre‐sowing and post‐emergence treatments of terbutryne on dry matter accumulation and moisture content in SPT (= Seed‐Parent Treated) and regular wheat seedlings were examined.No significant differences in simazine resistance between regular and SPT seed were found. However, there was a marked and significant increase in terbutryne resistance of SPT over regular seeds, which was expressed by a longer period to 50% seedling mortality as well as by a lower daily increase in mortality. Growth retardation, caused by pre‐ sowing as well as by post‐emergence terbutryne treatments, was appreciably less in the SPT seedlings than in the regular ones. The higher terbutryne resistance of the SPT seedlings may be attributable to their higher moisture content induced by the chlormequat. Effet du traitement des pieds meres avec le chlorméquat sur la résistance des plantules de blé a la terbutryne et à la simazine
SHOOT ZONE UPTAKE OF SOIL‐APPLIED HERBICIDES IN PISUM SATIVUM L.
Authors: O'BRIEN L. P. , PRENDEVILLE G. N. 
Published: July 2006

Summary. The effects of localized herbicide placement at different internodes of pea (Pisum sativum L. cv. Alaska) shoots below the soil surface after plant emergence were studied by removing the soil from around the shoots and replacing with herbicide‐treated soil. The first internode proved insensitive to linuron, diuron, atrazine and simazine at 4·5 kg/ha, while treatment of the second and third internodes markedly reduced plant growth 4–6 days after treatment. Separate exposure of the first internode alone, and the second and part of the third together to 14C‐labelled atrazine indicated no difference in herbicide metabolism. However, a two‐ to threefold increase in 14C uptake and movement to the foliar parts occurred when the second and part of the third internode was treated, as compared to first internode treatment. Thus the differential sensitivity of the internodes to atrazine, and possibly to the other herbicides, may be because the more mature first internode allows less uptake and subsequent movement to the foliar parts. Absorption dans la zone des tiges des herbicides appliqués dans le sol chez Pisum sativum L.
THE EFFECTS OF SOME CHEMICALS ON THE GERMINATION OF A WEED, PSORALEA CORYLIFOLIA L.
Authors: SHUKLA S. P. 
Published: July 2006

Summary. The effects of 2,4‐D, 2,4,5‐T, IAA and GA on the germination behaviour of one‐seeded pods of Psoralea corylifolia L. were studied. For each chemical, inhibition of germination of acid‐scarified pods increased with increase in concentration. The inhibition was irreversible and led to death of the seed in the pod. Morality, expressed as percentage of dead pods, was highest for 2,4,5‐T and IAA and lowest for GA. Impermeable or ‘hard’ pods were unaffected by the treatments. Though acid‐scarified pods were significantly damaged by an 8 h chemical treatment, weathered pods were unaffected by treatments of less than 30 h duration. After scarification, dry pods were more susceptible than pre‐imbibed ones. Rates of water uptake were determined for pods of both categories. Effets de quelgues produits chimiques sur la germination de Psoralea corylifolia L.
GROWTH, TUBER FORMATION AND SPREAD OF CYPERUS ROTUNDUS L. FROM SINGLE TUBERS*
Authors: HOROWITZ MENASHE 
Published: July 2006

Summary. Single tubers of Cyperus rotundus L. were planted at intervals over the year. Plant growth was slow and sprouting of tubers was inhibited at temperatures below 20°C, but tubers overwintered at temperatures above freezing point. In the warm season, plant growth and tuber formation rate closely followed air temperature and tubers were forming within 1 month from planting. No inflorescence appeared during the cool season.In autumn‐planted C. rotundus grown in containers, the ratio of aerial to subterranean weight decreased from 1·1 in December to 0·2–0·4 in summer. The weight of tubers in mid‐summer was about 10 times more than that present in December.Tubers formed at ail times of year and at various locations on plants sprouted readily in laboratory tests (76–100% sprouting). C. rotundus planted in March at wide spacings was grown in field conditions free of other plant competition for 20 months. Within 2 months the plants had spread to 90 cm. At the end of the first and the second summer of growth, the mean area of one plant was 7·6 m2 and 56·7 m2, respectively, and patches had expanded then by 2·8 m and 5·4 m, respectively, from the initial shoot. After 20 months of growth all tubers were present within the 0–40 cm soil depth, 60–70% of them in the 0–20 cm layer. About 30% of the tubers were within 1 m and 60% within 2 m of the plant centre.Under the patch centre there were about 1000 tubers per m2 with 0·3 kg dry weight; in the upper 20 cm more than 3500 tubers weighing 0·9 kg were present per m3 of soil. Croissance, formation de tubercules et propagation de Cyperus rotundus L. issu de tubercules uniques
SOME PHYSICO‐CHEMICAL INTERACTIONS OF PARAQUAT WITH SOIL ORGANIC MATERIALS AND MODEL COMPOUNDS
Authors: BURNS I. G. , HAYES M. H. B. , STACEY M. 
Published: July 2006

Summary. The adsorption equilibria of paraquat were investigated on a range of organic materials including an organic soil, various humic fractions of that soil, model polymers prepared by the oxidative coupling of benzoquinone, ion‐exchange resins (Zeo‐Karb 216 and 226) and a polystyrene resin (Amberlite XAD‐2). Isotherms were prepared for adsorption on the H+ and on some of the Ca2+ saturated materials. Measurement of the counter‐ion in solution at equilibrium, and correlation of the adsorption with exchange capacity for H+ adsorbents showed that ion exchange was the primary adsorption mechanism. Significant amounts of non‐exchange adsorption were also detected, especially at low concentrations, but generally the results followed the Rothmund‐Kornfeld isotherm equation fairly accurately. The Rothmund‐Kornfeld plots for the Ga2+ forms were complicated by the hydrolysis by water of some of the exchange sites. Other types of isotherm equations were tested and found to be unsatisfactory.Desorption of paraquat with HCl from organic soil preparations was less than expected, and the isotherms did not conform to the Rothmund‐Kornfeld or to the mass action equations. The probable reasons for this behaviour arc discussed.Quelques interactions physico‐chimiques du paraquat avec des matériaux de sol organique et des composés modèlesII. Adsorption, désorption et équilibre dans les suspensions aqueuses
TEMPERATURE VARIATIONS IN THE SURFACE LAYERS OF AN AGRICULTURAL SOIL*
Authors: STOLLER E. W. , WAX L. M. 
Published: July 2006

Summary. Continuous measurements of soil temperatures were made at 1·3, 2·5, 5·1, 10·2, 15·2 and 20·3 cm below the barren surface of a Drummer silty clay loam during 1969. Annual average temperature at all these soil levels was higher than the air temperature 122 cm above the soil surface. The daily fluctuations in soil temperatures were greater in summer than in winter and were greater down to depths of 5·1 cm than the fluctuations in air temperature. The maximum and minimum temperatures for the year, of the air, 1·3‐cm and 20·3‐cm depths were 34 and ‐ 19,46 and ‐ 18, and 33 and ‐ 8°C, respectively. On near cloudless days, the soil temperatures showed a pattern of amplitude reduction and phase retardation with depth, as the soil layers warmed and cooled.Variations de la température dans les couches super ficielles d'un sol agricole
A TECHNIQUE FOR STUDYING THE RATE OF ROOT GROWTH OF INTACT SEEDLINGS IN A HERBICIDE MEDIUM
Authors: O'SULLIVAN P. A. , PRENDEVILLE G. N. 
Published: July 2006

Summary. Time‐lapse cine photography was used to record intact seedling root growth of pea and barley during separate exposure of root, shoot + seed, or entire needling to herbicides. The shoot + seed and the root zones were isolated in two square Petri dishes fixed edge to edge, and separately treated with moistened herbicide‐treated sand. The seated dishes were placed at an angle of 30° in a photographic chamber. Photographs of roots were automatically recorded at 10‐min intervals on 16 mm high speed reversal film over 72 h. Root length images on film were measured using an ocular micrometer. Root growth of pea and barley seedlings was normal when the shoot + seed zone was treated with 2,4‐D at 1 and 10 ppm, respectively. In similar treatment of roots growth inhibition occurred after approximately 20 h in both plants, and root growth ceased alter 32 h in peas, and 57 h in barley. These results indicate the inherent tolerance of barley roots to 2,4‐D.Technique pour l'étude du taux de croissance des racines intactes de plantules dans un milieu herbicide
THE INTERRELATIONSHIP BETWEEN TILLERS AND RHIZOMES OF POA PRATENSIS L.—AN AUTORADIOGRAPHIC STUDY
Authors: NYAHOZA FELIX , MARSHALL C. , SAGAR G. R. 
Published: July 2006

Summary. The main shoot or selected tillers of seedling plants of Poa pratensis L. were supplied with 14CO2 and the distribution of 14C‐assimilates was followed by autoradiography. The primary tillers were initially supplied with 14C‐assimilates from the main shoot but, once established, became independent of the parental shoot for carbohydrates. Similarly, developing rhizome‐tillers were supported by the main shoot and established primary tillers but soon became self‐supporting, Defoliation of all the tillers of the plant but one led to the defoliated primary and rhizome tillers being supplied with radiocarbon from the remaining intact shoot. Thus, although the primary tillers and rhizome‐tillers in the intact plant appear to be physiologically independent, the entire tiller‐rhizome system may be re‐integrated after defoliation, allowing assimilate redistribution. P. pratensis may be regarded as a convenient link between the non‐weedy herbage grasses which generally lack rhizomes and the weedy rhizomatous grasses typified by Agropyron repens (L.) Beauv. Etat des relations entre les talles et les rhizomes de Poa pratensis L. Etude autoradiographique
AMINOTRIAZOLE METABOLISM IN CIRSIUM ARVENSE (L.) SCOP. AND PISUM SATIVUM L.
Authors: SMITH LEON W. , CHANG FA‐YAN 
Published: July 2006

Summary. Excised leaves as well as intact plants of Canada thistle (Cirsium arvense (L.) Scop.) metabolized 3‐amino‐l,2,4‐triazole (aminotriazole) to three major products, Unknowns II, 1a and 1b. Unknown II was identical to β‐(3‐amino‐l,2,4‐triazolyl‐l‐)α‐alanine. Unknowns 1a and 1b, previously described as one product, were separated by electrophoresis and thin layer chromatography. Unknown 1a appeared to be a metabolic product of Unknown II while Unknown 1B was derived from Unknown 1a. An enzyme preparation from pea (Pisum sativum L. cv. Thompson Laxton) seedlings capable of synthesizing tryptophan from indole and serine was also able to metabolize aminotriazole. Tryptophan synthesis with the enzyme preparation was inhibited by aminotriazole and evidence suggests that aminotriazole metabolism may follow a similar pathway to tryptophan synthesis. Métabolisme de l'aminotriazole chez Cirsium arvense (L.) Scop, et Pisum sativum L.
DEGRADATION OF DICAMBA IN PRAIRIE SOILS
Authors: SMITH ALLAN E. 
Published: July 2006

Summary. Electron‐capture gas chromatography was used to detect dicamba residues in three prairie soils, and the breakdown under different moisture conditions was studied. At rates equivalent to 1·1 kg/ha degradation was rapid in all soils at 25°C and at moisture levels in excess of the wilting point, with over 50% of the applied dicamba being dissipated in 2 weeks. Negligible breakdown occurred in the sterile soils, over a 4–week period, indicating that microbial decomposition could be an important factor contributing to dicamba degradation.The persistence of dicamba was investigated under field conditions at three locations using small plots. Applications equivalent to 1·1 kg/ha were made in October 1971 for analysis in May 1972, and in May 1972 for analysis in August 1972. At both sampling dates no dicamha residues were detected in any of the treatments at the 0–5, 5–10 or 10–15 cm soil levels.Degradation du dicamba dans les sots de prairies
SELECTIVITY OF BENZENE SULPHONYL CARBAMATE HERBICIDES BETWEEN DIFFERENT GRASS SPECIES AND CLOVER
Authors: BLAIR A. M. , HOLROYD J. 
Published: July 2006

Summary. In field experiments extending over the period 1964–68 wettable powder and water soluble formulations of asulam and M & B 8882 were applied to a range of grass species in summer and autumn. Phleum pratense L., Dactylis glomerata L., Holcus lanatus L., Agrostis tenuis Sibth. and Poa trivialis L. were more susceptible than Lolium perenne L., Festuca pratensis Huds. and Festuca rubra L., although effects were more persistent on H. lanatus than on the other species. Trifolium repens L. (white clover) was more resistant to M & B 8882 than to asulam, particularly in July. The pattern of selectivity was similar with summer and autumn treatment, but effects were slower to develop in the autumn.Sélectivité des herbicides a base de carbamate de benzène sulfonyle entre différentes espèces de graminées et le trèfle
VERTICAL DISTRIBUTION OF HERBICIDES IN SOIL AND THEIR AVAILABILITY TO PLANTS: SHOOT COMPARED WITH ROOT UPTAKE
Authors: WALKER A. 
Published: July 2006

Summary. Turnip, lettuce and ryegrass seedlings showed toxicity symptoms following shoot exposure to atrazine, linuron and aziprotryne at soil concentrations less than would be obtained from normal field applications. Responses following shoot exposure to simazine and lenacil were much less. Root exposure to all five herbicides caused seedling death at concentrations lower than those required for ‘shoot‐zone’ toxicity. Pronamide and chlorpropham were tested against ryegrass only and at the concentrations examined were toxic only when localized in the shoot zone. Root exposure suppressed root growth, but the shoots were able to grow normally if the soil was kept sufficiently moist. Shoots contained more 14C‐atrazine at emergence after shoot exposure compared with root exposure, but there was little subsequent uptake from the shoot zone. There was extensive uptake from the root zone after emergence. In the shoot‐zone treatments, concentrations in the plant were high at emergence but were rapidly diluted by plant growth, whereas with root exposure, they increased throughout the experiments. The possible significance of these results to herbicide bebaviour under field conditions is discussed.La distribution verticale des herbicides dans le sol et leur disponibilité pour les plantes: absorption comparée par la partie aèrienne et par les radnes