bluuebunny/crossref_metadata_2025_split huggingface dataset:
Problems in control of Rottboellia exaltata L.f. in maize in Bukidnon Province, Mindanao, Philippines
Authors: FISHER H. H. , LOPEZ F. , MARGATE L. , ELLIOT P. , BURRILL L. 
Published: July 2006

SummaryVarious methods were tested to control the annual grass Rottboellia exaltata L.f. in maize (Zea mays L.) under small‐farm conditions in Bukidnon Province, Mindanao, Philippines during 1977 and 1978.No single method was satisfactory. Despite adequate early season control, late‐germinating Rottboellia tillered profusely. By harvest, plots had heavy infestations and were carpeted with seed. At harvest, untreated controls averaged 8·6 t Rottboellia dry matter ha−1 and only half the maize yield of handweeded plots.The ‘karase’ spike‐tooth harrow, or 0·2 kg paraquat ha−1, effectively removed Rottboellia flushes before maize emergence, but these techniques delayed planting, which can intensify downy mildew disease (Sclerospora sp.). Even though handweeding increased maize yields and decreased Rottboellia dry weights, it is impractical on typical 3‐ to 5‐ha maize farms. Mungbean (Vigna radiata (L.) Wilczek var. aureus), intercropped with maize, suppressed Rottboellia initially. Openings caused by mungbean harvest, however, allowed explosive late‐season weed growth in maize.Three herbicide treatments were as effective as handweeding: pendimethalin plus atrazine, either banded over the maize row (followed by cultivation), or broadcast; and pendimethalin followed by 2, 4‐D, both broadcast.In one experiment, low‐cost practices, including weed flush removal, cultivation, or handweeding, provided high net returns, whereas expensive herbicide treatments produced low net returns.Fertilizer, applied without weed control, increased maize yield 62%. Without fertilizer, weed control increased yield 107%. Combining the two raised yield 167%.
Prediction of Sorghum halepense (L.) Pers. rhizome sprout emergence in relation to air temperature
Authors: SATORRE E. H. , GHERSA C. M. , PATARO A. M. 
Published: July 2006

SummaryThe dynamics of Sorghum helpense (L.) Pers. rhizome sprout emergence was followed in three different crop systems. A simple exponential model relating the number of rhizome sprouts m−2 to accumulated thermal units, calculated as the sum of the daily mean air temperatures above 15°C, provided a good estimate of cumulative shoot emergence populations (r2= 0·93) over all sampling dates between June and January. A good description of the dynamics of shoot emergence in an independent experiment was obtained from the model.The possible influence of the crop structure and soil water supply in relation to the model fitness is discussed.
Wild oats (Avenu fatua L.) seed dormancy as influenced by sodium hypochlorite, moist storage and gibberellin A3
Authors: HSIAO A. I. , QUICK W. A. 
Published: July 2006

SummaryIncubation in gibberellin A3 (GA3) or a 1 h immersion pretreatment with 800 mm sodium hypochlorite (NaOCl) both promoted 20% germination of freshly harvested dormant wild oat (Avena fatua L.) seeds that had been imbibed on water for 10 days. GA3 immediately following 1 h NaOCl immersion pretreatment induced maximum germination. Moist storage (MS) after NaOCl immersion pretreatment resulted in less germination on transference of the seeds to GA3, indicating that GA3 responsiveness was lost during MS. These seeds required a repeal NaOCl immersion plus a GA3 treatment to induce maximum germination. However, GA3 still gave maximum germination if the seeds were stored dry after initial NaOCl immersion. Seeds with water‐induced dormancy responded similarly to freshly harvested dormant seeds when treated with NaOCl, MS, or GA3. Seeds afterripened a longer time had a reduced requirement for exogenous GA3 in the breaking of dormancy indicating that the depth of the GA3‐dependent dormancy decreased with duration of after‐ripening.Dormant dehulled seeds with a brief NaOCl pretreatment germinated about 30% on water but gave maximum germination when incubated on GA3, an effect that persisted even after 21 days of MS. This effect, coupled with the previous findings, suggested that the NaOCl treatment weakened membrane barriers of the seed coat through a scarification‐like effect, similar to the effects of piercing and acid immersion, and thereby produced increased sensitivity to the presence of GA3. The loss of responsiveness to GA3 in NaOCl‐treated seeds during MS may involve the restoration of integrity of the seed coverings, a process occurring only in the imbibed state, and, presumably, most rapidly in freshly harvested, intact seeds.
Use of substituted urea herbicides for weed control in Euphorbia lathyris L., a potential fuel‐producing crop
Authors: GARCIA‐BAUDIN J. M. , LANSAC A. R. , AYERBE L. , TENORIO J. L. , CADAHIA E. 
Published: July 2006

SummarySome substituted urea herbicides (chlortoluron, diuron and methabenzthiazuron) were tested for possible use in the cultivation of Euphorbia lathyris L. Diuron showed high phytotoxicity for this species, which was tolerant to chlortoluron and methabenzthiazuron. In preliminary experiments two triazine herbicide (atrazine and simazine) were also used, but both were so toxic to E. lathyris that their use was not continued beyond this stage.In glasshouse experiments, chlortoluron showed slight phytotoxicity to E. lathyris but this did not appear in field experiments. Both chlortoluron and methabenzthiazuron were very efficient against weeds which were present and significantly increased yield of E. lathyris in comparison with unweeded plots. The poor competitive ability of E. lathyris against weeds was confirmed.
Effect of chlorfenprop‐methyl, flamprop‐isopropyl and benzoylprop‐ethyl on 14C2 fixation in Avena fatua L., Triticum aestivum L. and Hordeum vulgare L.
Authors: BERGMANNOVA EVA , TAIMR L. 
Published: July 2006

SummaryThe effect of chlorfenprop‐methyl, flampropisopropyl and benzoylprop‐ethyl on 14CO2 fixation was followed in wild oat (Avena fatua L.), barley (Hordeum vulgare L., cv. Ametyst), and wheat (Triticum aestivum L., cv. Mironovská). Experimental plants were exposed to a 14CO2‐enriched atmosphere in a special apparatus 2 h, 1, 3, and 9 days after the herbicide treatment.Chlorfenprop‐methyl already inhibited 14CO2 fixation in wild oat plants 2 h after the treatment. 14C‐metabolite transport to the roots was strongly decreased. Both 14CO2 fixation and 14C‐metabolite level in the roots were significantly depressed in A. fatua when compared with untreated plants at the last sampling time. 14C incorporation into starch was inhibited from the first day after treatment, and on day 9 was lowered more than ten fold in treated plants.Flamprop‐isopropyl inhibited 14CO2 fixation in wild oat plants from day 3 after treatment, but benzoylprop‐ethyl not until day 9. Both herbicides also decreased 14C incorporation into starch in A. fatua. Chlorfenprop‐methyl also slightly decreased 14CO2 fixation in barley on day 9. However, assimilate transport into the roots and 14C incorporation into starch were not affected. Flamprop‐isopropyl inhibited 14CO2 fixation in barley plants only on the first day after treatment, and assimilate transport was also reduced. By contrast, no differences from untreated plants were found at the end of the experiment. Benzoylprop‐ethyl did not decrease either 14CO2 fixation or assimilate transport to the roots in wheat, but it inhibited starch synthesis. Atrazine depressed 14CO2 fixation in wild oat plants by 91%, in wheat plants by 99% compared with untreated plants. Assimilate transport into the roots was also strongly inhibited. In contrast to atrazine, the effect of chlorfenprop‐methyl, flamprop‐isopropyl, and benzoylprop‐ethyl on CO2 fixation seems to be secondary.
Effects of three herbicides used to control volunteer ryegrass on tillering and seed yield of two second year perennial ryegrass crops
Authors: OSWALD A. K. 
Published: July 2006

SummaryAtrazine, chlorpropham and diuron gave excellent control of volunteer perennial ryegrass seedlings and reduced vegetative tillers of perennial ryegrass grown in the glasshouse and for seed in the field. However, there was no compensation in terms of the fertile tillers or seed weight during the second year. The results suggest that the lack of positive effect on seed yield may be due to direct effects on the crop from the residual herbicides.
Mapping of atrazine resistance for Amaranthus retroflexus L. in Hungary
Authors: SOLYMOSI P. , KOSTYAL S. 
Published: July 2006

SummaryThe study extending over all sixteen counties of Hungary has shown atrazine resistant biotypes of Amaranthus retroflexus L. to grow not only in and around maize monocultures but also in rotationally grown maize and even along highways and ruderal areas. In the present study made in 1983 resistant A. retroflexus was found in five counties (Bács‐Kiskun, Csongrád, Hajdu‐Bihar, Nógrád and Szabolcs‐Szatmár) where Hartmann recorded it as absent in 1976. In addition, resistant populations were also found in the counties of Szolnok and Veszprém. The area in which populations of A. retroflexus have developed resistance to atrazine therefore appears to be extending.
Effects of isoproturon in the rhizosphere of wheat
Authors: MUDD P. J. , GREAVES M. P. , WRIGHT S. J. L. 
Published: July 2006

SummaryIn a field experiment, isoproturon (as Arelon) applied to soil at 2·5 kg ai ha−1 caused variable effects in the rhizosphere of winter wheat. These included transient increases and decreases in the number of bacterial and fungal propagules. No changes in soil levels of NH4+‐N, NO2−‐N, NO3−‐N or PO43− were detected. Similar results were recorded with wheat grown in pots and in laboratory‐incubated soil.Arelon (1–60 μg ai ml−1) did not affect pure cultures of bacteria but at the highest concentration (approximating to fifty times field rate) inhibited growth of some fungi. The value of laboratory and field experiments for studying effects of pesticides on micro‐organisms is discussed. The results suggest that Arelon, in practical use, is unlikely to have harmful effects on the micro‐organisms or fertility of soil.
Dégradation catalytique de carbamates herbicides déposés sur bentonites homoioniques. III. Cas du phenmédiphame et du desmédiphame
Authors: Et J. SABADIE , COSTE C. M. 
Published: July 2006

Résumé: Summary: ZusammenfassungLa dégradation chimique en phase sèche du phenmédiphame et du desmédiphame a étéétudiée à température ambiante sur diverses bentonites homoioniques (Fe3+, Mn2+, Cu2+, Ag+ et Zn2+). Le cuivre, l'argent et le zinc sont actifs. Le schéma général du processus de dégradation proposé indique que seule la fonction carbamate intercycles est hydrolysée selon un mécanisme type E1cB (formation d'isocyanate intermédiaire).The chemical degradation of phenmedipham and desmedipham on various homoionic bentonites (Fe3+, Mn2+, Cu2+, Ag+ and Zn2+) was investigated at room temperature. In these conditions. Cu2+, Ag+ and Zn2+ were the most active cations. The chemical degradation pathway proposed only indicates the hydrolysis of the carbamate function located between the two aromatic nuclei according to the E1cB mechanism (isocyanate is involved as intermediate).Katalytischer Abbau von Carbamatherbiziden auf homionischen Bentoniten. III. Phenmediphan und DesmediphaEs wurde der chemische Abbau von Phenmedipham und Desmedipham auf verschiedenen homoionischen Bentoniten (Fe3+, Mn2+, CU2+. Ag2+ und Zn2+) bei Zimmertemperatur untersucht. Unter den gegebenen Versuchsbedingungen waren Cu2+, Ag+, und Zn2+, die aktivsten Kationen. Es wird angenommen, dass der chemische Abbau auf einer Hydrolyse der Carbamatfunktion zwisehen den zwei aromatischen Ringen beruht und einem Mechanismus vom Typ E1cB (Bildung von intermediärem Isocyanat) folgt.
Dégradation catalytique de carbamates herbicides deposés sur bentonites homoïoniques. IV. Cas du carbetamide
Authors: Et J. SABADIE , COSTE C. M. 
Published: July 2006

Résumé: Summary: ZusammenfassungEn phase sèche à 20° C, le carbétamide peut se dégrader lentement sur divers supports argileux homoïoniques (Bentonite Prolabo, Montmorillonite K 10; Cu++, Zn++, Fe+++). Le Cuivre présente la meilleure activité. Un processus de dégradation suivant deux voies parallèles a été mis en évidence au cours de la première étape. La sélectivité observée est influencée par la méthode d'imprégnation, la nature du support et du métal. A température supérieure (80° C), on observe sur gel de silice et Montmorillonite K 10 un processus plus complet de dégradation qui permet de confirmer la formation d'isocyanate intermédiaire lors de l'hydrolyse de la fonction carbamate du substrat.Surface catalysed degradation of carbamate herbicides on bentonites. IV. CarbetamideThe chemical degradation of carbetamide on various homoionic clays (Bentonite Prolabo, Montmorillonite K 10:Cu++, Zn++, Fe+++) (was investigated at room temperature. The kinetics of the reaction was generally slow; however, copper was the most active metal. The first stage of the chemical process included two ways of degradation. The selectivity of the conversion was influenced by the impregnation technique, clay type and exchange metal. At a higher temperature (80° C) on silica gel and montmorillonite K 10, the whole process of degradation was observed which indicated that isocyanate is involved as an intermediate in the carbamate hydrolysis function.Katalytischer Abbau von Carbamaten an Bentaniten. IV. CarbetamidDer chemische Abbau von Carbetamid an verschiedenen homoionischen Tonmineralen (Bentonit Prolabo, Montmorillonit K 10; Cu2+, Fe3+) wurde bei Zimmertemperatur untersucht. Die Reaktion war allgemein langsam, aber Kupfer war am wirksamsten. Die erste Stufe des Abbaus besteht aus zwei Wegen, worüber die Art der Imprägnierung, das Tonmineral und die ausgetauschten Metalle entscheiden. Bei höherer Temperatur (80° C) konnte an Silicagel und Montmorillonit K 10 der gesamte Abbauprozess beobachtet werden, wobei sich zeigte, dass Isocyanat als Zwischenprodukt der Hydrolyse von Carbamat auftritt.
Effect of atrazine on growth, production of aflatoxin, and fatty acid and sterol biosynthesis by Aspergillus spp.
Authors: FERNANDO T. , BEAN G. , GLENN S. 
Published: July 2006

Summary: Résumé: ZusammenfassungThe effects of atrazine were studied on growth, production of aflatoxin, and fatty acid and sterol biosynthesis by four isolates of Aspergillus in vitro. There was little effect of atrazine on Aspergillus spp. at concentrations up to 20 μg ml−1 but at 40 μg ml−1 or above, growth, production of aflatoxin, and fatty acid and sterol biosynthesis were remarkably reduced. Palmitic, stearic and linoleic acid synthesis were inhibited in three of the isolates tested at 60 μg ml−1. At 100 μg ml−1, except ergosterol, the cholesterol and 5, 7‐ergostadienol synthesis was totally inhibited in all isolates. Effet de l'atrazine sur la croissance, la production d'aflatoxine, et la biosynthèse d'acides gras et de stérols par Aspergillus spp.Chez quatre isolats d'Aspergillus, les effets de l'atrazine sur la croissance, la production d'aflatoxine, et la biosynthèse d'acides gras et de stérols ont étéétudiés in vitro. Jusqu'à des concentrations de 20 μg ml−1, l'atrazine n'a eu que peu d'effets, mais à 40 μg ml−1 et au‐dessus, la croissance, la production d'aflatoxine, et la biosynthèse d'acides gras et de stérols ont été nettement réduites. Les synthèses d'acides palmitique, stéarique et linoléique ont été inhibées chez trois des isolats, à 60 μg ml−1. A 100 μg ml−1, mis à part l'ergostérol, les synthèses de cholestérol et de 5, 7‐ergostanediol ont été totalement inhibées chez tous les isolats. Die Wirkung von Atrazin aufdas Wachslum, die Bildung von Aflatoxin und die Fettsäuren‐ und Sterol‐Biosynthese von Aspergillus spp.Bei vier Isolaten von Aspergillus wurde in vitro die Wirkung auf das Wachstum sowie auf die Bildung von Aflatoxin, Fettsäuren und Sterolen untersucht. Bei Atrazin‐Konzentrationen bis zu 20 μg ml−1 war keine Wirkung zu beobachten, aber ab 40 μg ml−1 wurden das Wachstum und die Bildung von Aflatoxin, Fettsäuren und Sterolen deutlich herabgesetzt. Bei 60 μg ml−1 war bei drei Isolaten die Bildung von Palmitin‐, Stearin‐ und Linolensäure gehemmt. Bei 100 μg ml−1 war bei alien Isolaten die Bildung von Cholesterol und 5, 7‐Ergostadienol, aber nicht Ergosterol, unterbunden.
Distribution of diclofop‐methyl and metabolites in oat (Avena sativa L.) protoplasts
Authors: HOLL F. B. , TRITTER S. A. , TODD B. G. 
Published: July 2006

Summary: Résumé: ZusammenfassungThe metabolism of the herbicide diclofop‐methyl and the distribution of it and its metabolites have been investigated in a system utilizing isolated oat protoplasts (Avena sativa L. ‘Cascade’). Accumulations of 14C‐diclofop‐methyl were found in membrane fractions of the protoplasts. Diclofop‐methyl partitioned into the lipid phase of the protoplast plasma membrane. Comparatively small amounts of diclofop were found associated with the protoplasts. Diclofop‐methyl was converted to diclofop in the treatment solution by hydrolytic enzymes associated with the external surface of the protoplast. Approximately 78% of the radiolabel recovered from the treatment solution was diclofop. The two major accumulations of radiolabel were found in the water insoluble portion (membrane fraction) of the protoplast as diclofop‐methyl and in the treatment solution as diclofop. Repartition du diclofop‐methyl et de ses métabolites dans les protoplastes d'avoine (Avena sativa L.)Le métabolisme de l'herbicide diclofop‐methyl (DM) et la répartition du DM et de ses métabolites ont étéétudiés dans un système faisant appel à des protoplastes d'avoine isolés (Avena sativa L.) ‘Cascade’. Des accumulations de 14C‐diclofop‐methyl ont été trouvées dans la fraction membranaire des protoplastes. Le diclofop‐methyl est passé dans la phase pidique de la membrane plasmique du protoplaste. En comparaison, de petites quantités de diclofop ont été trouvées en association avec les protoplastes. Le diclofop‐methyl a été converti en diclofop par des hydrolases associées à la surface externe des protoplastes. Approximativement 78% des traces radioactives retrouvées dans la solution de traitement étaient du diclofop. Les deux principales accumulations de radioactivitéétaient trouvées dans la fraction insoluble dans l'eau des protoplastes (fraction membranaire) sous forme de diclofop‐méthyl et, dans la solution de traitement, sous forme de diclofop. Verteilung von Diclofop‐methyl und Metaboliten in Hafer‐ (Avena sativa L.)‐ProtoplastenDer Abbau von 14C‐markiertem Diclofop‐methyl und die Verteilung des Wirkstoffs sowie eines Metaboliten wurden in isolierten Protoplasten von Hafer (Avena sativa L. ‘Cascade’) untersucht. Der Wirkstoff war in den Protoplastenmembranen angereichert, wobei eine Anlagerung an die Lipidphase der Plasmamembran festgestellt wurde. Von Diclofop waren vergleichsweise geringe Mengen an die Protoplasten gebunden. Diclofop‐methyl wurde in der Versuchslösung durch hydrolytische Enzyme, die an der Protoplastenaussenfläche lagen, zu Diclofop umgewandelt. Radioaktiv markierte Stoffe wurden hauptsächlich als Diclofop‐methyl am Protoplasten‐membransystem und als Diclofop (mit 78% der eingebrachten 14C‐Aktivität) in der Lösung gefunden.
Variation in Chrysanthemoides monilifera (Compositae) in eastern Australia
Authors: SIMMONS D. M. , FLINT P. W. 
Published: July 2006

Summary: Résumé: ZusammenfassungPopulations of Chrysanthemoides monilifera ssp. monilifera and C. monilifera ssp. rotundata were sampled over their ranges on mainland eastern Australia, and the extent of geographic variation in some morphological characters determined, Both subspecies were morphologically relatively homogeneous over the populations sampled and no obvious patterns of phenotypic variation within them were detected. The subspecies were readily distinguished from each other and no intermediate forms were observed. However there was more phenotypic variation in ssp. monilifera than in ssp. rotundata. The subspecies have ranges in Australia broadly corresponding to their climatic ranges in South Africa, and ssp. monilifera occurs over a wider climatic range in Australia than ssp. rotundata. Further work on genotypic variation within the species is needed. Variation chez Chrysanthemoides monilifera (Compositae) en Australie orientaleDes populations de Chrysanthemoides monilifera spp. monilifera et C. monilifera spp rotundata ont été prélevées dans leur site en Australie de l'Est et l'étendue de la variation géographique pour quelques caractères morphologiques déterminée. Les deux sous‐espèces étaient relativement homogènes pour les populations collectées et aucun exemple évident de variation phénotypique au sein d'entre elles n'a été mis en évidence. En revanche, les deux sous‐espèces étaient bien distinctes entre elles et aucune forme intermédiaire n'a été observée. Cependant, il y avait plus de variabilité phénotypique chez spp. monilifera que chez ssp. rotundata. Les sous‐espèces ont une répartition en Australie en relation avec leur répartition climatique en Afrique du Sud et ssp. monilifera est présente sur une plus large aire climatique en Australie que ssp. rotundata. Des travaux supplémentaires sur la variabilité génétique intra espèce s'avèrent nécessaires. Variabilität von Chrysanthemoides monilifera (Compositae) in Ost‐AustralienDie geographische Variabilität der Unterarten monilifera und rotundata von Chrysanthemoides monilifera wurde an Pflanzen, die in ihren Verbreitungsgebieten in Ost‐Australien gesammelt worden waren, an einigen morphologischen Eigenschaften bestimmt. Beide Unterarten waren morphologisch recht einheitlich, wenn auch die ssp. monilifera eine grössere phänotypische Variabilität hatte. Die Unterarten liessen sich einfach unterscheiden, und es wurden keine intermediären Formen beobachtet. Die Verbreitung der Unterarten in Australien entspricht weitgehend ihren klimatischen Arealen in Südafrika, so dass die ssp. monilifera in Australien einen klimatisch weiteren Bereich besiedelt als ssp. rotunda. Die Art muss eingehender genotypisch untersucht werden.
Comparison of chlorsulfuron and metsulfuron for control of Allium vineale L.
Authors: LEYS A. R. , SLIFE F. W. 
Published: July 2006

SummaryThe response of natural and planted stands of Allium vineale L. to chlorsulfuron and metsulfuron was determined in field experiments in Illinois, U.S.A., in 1982 and 1983. In natural stands very low rates of either herbicide controlled A. vineale. Chlorsulfuron, applied in the spring at 20 g ha−1, reduced aerial bulblet production by 99% but when it was applied in the fall it reduced aerial bulblet production by only 59%. All rates of metsulfuron (5–20 g ha−1), at both times of application, effected better than 94% reduction in plant density and yield of aerial bulblets. In a glasshouse experiment, plants derived from aerial bulblets were more susceptible to chlorsulfuron than plants derived from soft offset bulbs. Soft offset bulbs were, therefore, used to establish a uniform stand of A. vineale in the field. In this experiment, non‐linear regression analysis showed that metsulfuron was two to three times more active than chlorsulfuron. GR95 values calculated from the computed regression equations show that metsulfuron and chlorsulfuron, applied in April at 5 and 15 g ha−1, respectively, reduced aerial and underground bulb production by 95%.
Joint action of Cochliobolus lunatus and atrazine on Echinochloa crus‐galli (L.) Beauv.
Authors: SCHEEPENS P. C. 
Published: July 2006

SummaryThe potential of the endemic fungus Cochliobolus lunatus as a biological control agent against Echinochloa crus‐galli was investigated. Under appropriate conditions the fungus produced leaf necrosis on E. crus‐galli resulting in death of young seedlings. However, plants with more than two leaves mostly recovered after some time. Bean, barley, maize, oat, rye, tomato and wheat were highly resistant to the fungus. In experiments in a climate room or in a glasshouse E. crus‐galli with more than two leaves could effectively be controlled by C. lunatus in combination with a sub‐lethal dosage of atrazine as low as 2.5 mg m−2 due to a positive interaction between fungus and herbicide.