bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparison of the effects of sward improvement on invertebrates, sward establishment and herbage yield
Authors: ELLIS S. A. , CLEMENTS R. O. , BALE J. S. 
Published: February 2008

SummaryField experiments were done at two widely separated sites in England (Tadcaster, North Yorkshire and North Wyke, Devon). In each case an old permanent sward was re‐seeded after ploughing or by direct drilling, or was left intact and fertilised. The carbamate pesticide aldicarb was applied to half of each experimental plot. The effects of sward improvement and pesticide on various soil invertebrate groups were assessed. Soil‐dwelling macrofauna arthropods were scarce at both sites. Stem‐boring dipterous larvae, however, were numerous at both sites. At Tadcaster, Oscinella vastator was the only species present in the original sward, but 0. frit was by far the most prevalent species in re‐seeded areas. These can only have arisen from direct oviposition of eggs by adults on or near the emerging seedlings and not by migration of larvae from buried turf or the desiccated old pasture.Mites and Collembola were abundant. Their numbers were reduced initially by cultivation and pesticide usage, but the effects of these practices were transient and their numbers recovered to previous levels usually within 10 wk.Earthworms were present at both sites. Deep burrowing species, e.g. Lumbricus terrestris and Allolobophora longa were less affected by the treatments imposed than species such as A. chlorotica and L. rubelius which usually live close to the soil surface. Effects on their numbers were in any case, short‐lived.No improvement method consistently provided the greatest herbage dry matter yield. Pesticide application, however, greatly increased seedling stand and/or herbage yield at both sites and showed the benefits of using crop protectants, especially on direct‐drilled re‐seeds.
A key for stages of development of the faba bean (Vicia faba)
Authors: KNOTT C. M. 
Published: February 2008

SummaryA key is presented to describe stages of development of the faba bean (Vicia faba), and is based on similar principles to the key for peas (Pisum sativum) (Knott, 1987). The coded description is divided into five principal stages; germination and emergence, vegetative, reproductive, pod senescence and stem senescence. These are sub‐divided into secondary stages. The practical use of the key is discussed with reference to timing of crop husbandry operations.
The effects of yellowing viruses on yield of sugar beet in field trials, 1985 and 1987
Authors: SMITH HELEN G. , HALLSWORTH PHILIPPA B. 
Published: February 2008

SummaryThe separate effects of beet yellows virus (BYV) and beet mild yellowing virus (BMYV) on yield of sugar‐beet cultivars inoculated at different growth stages were assessed in field trials in 1985 and 1987. Early or mid‐season inoculation decreased sugar yield by up to 47% for BYV, and up to 29% for BMYV. Infections after the end of July had no significant effect on yield. Both viruses caused significant increases in the juice impurities sodium, potassium and amino‐nitrogen after infecting plants early in the season. Yield losses associated with infection were determined by the causative virus, the time of infection, and susceptibility of the sugar‐beet cultivars.
Interactions of Meloidogyne javanica, Fusarium udum and Rhizobium on pigeon pea in the presence of nickel and cobalt as pollutants
Authors: KHAN M. WAJID , SALAM M. ABDUL 
Published: February 2008

SummaryThe interactions between Meloidogyne javanica, Fusarium udum and Rhizobium on pigeon pea, in the presence of nickel (Ni) and cobalt (Co) as soil pollutants, were studied. In single inoculations, M. javanica caused a reduction in plant growth, particularly at higher inoculum levels (1000 and 10 000 JJ2). Fusarium udum induced wilting symptoms and the higher concentrations of Ni and Co suppressed plant growth. Meloidogyne javanica and F. udum interacted to show more severe wilting symptoms than F. udum alone. Wilting was completely inhibited by Ni but reductions in plant growth and nodulation occurred. In the presence of Ni, M. javanica did not cause galling but nodulation was suppressed. Cobalt also suppressed wilting and nodulation but interacted with M. javanica to increase root galling and to reduce plant growth by a greater amount than the total of reductions caused by the individual treatments.
Organophosphorus resistance in Aphis gossypii (Hemiptera: Aphididae) on chrysanthemum in the UK
Authors: FURK C. , VEDJHI S. 
Published: February 2008

SummaryThe FAO standard dip‐test was used to test resistance of glasshouse populations of Aphis gossypii from chrysanthemums to the organophosphorus insecticides heptenophos and diazinon. Compared with a susceptible population collected in 1981, resistance factors to diazinon of up to 538 were found in populations collected after 1984. Resistance to heptenophos was less than that to diazinon but some populations collected after 1984 were 34 times as resistant as the susceptible strain. Possible reasons for the sudden increase in resistance in A. gossypii and current prospects for control of resistant populations are discussed.
Weed management in direct‐seeded lowland rice under iron toxic sites in Nigeria
Authors: IMEOKPARIA P. O. 
Published: February 2008

SummaryField trials carried out during the wet season of 1987 at Edozhigi in the Southern Guinea Savanna and in 1988 at Bende in the Forest Zones of Nigeria indicate that the performance of rice varieties under iron toxic soils could be improved by delayed flooding due to the application of selective soil persistent herbicides. Yield increments of 33.3% and 76.9% were recorded at Edozhigi when the mixture of oxadiazon plus propanil at 0.5 + 2.4 kg a.i./ha was applied compared with bentazon alone at 3.0 kg a.i./ha under IR26 and Farox 306–3–6 (susceptible). Similarly at Bende, yield increments of 76.1% and 84.6% were obtained when the mixture of piperophos plus dimethametryn at 1.6 + 0.4 kg a.i./ha was applied compared with pre‐emergence butachlor alone at 4.0 kg a.i./ha also under IR26 and Farox 306–3–6. Breeding resistance to iron toxicity will be desirable because of poor peristence of herbicides in warm flooded soils.
Resistance to the aphids Sitobion avenae and Rhopalosiphum padi in Gramineae in relation to hydroxamic acid levels
Authors: THACKRAY D. J. , WRATTENT S. D. , EDWARDS P. J. , NIEMEYER H. M. 
Published: February 2008

SummaryAribiotic resistance to the aphid Sitobion avenae was assessed in relation to levels of hydroxamic acids (Hx) in a wide genetic range of cultivars and species of Triticum. Within hexaploid and tetraploid Triticum material, total plant concentrations of Hx explained a significant proportion of the variation in intrinsic rate of increase (rm) of S. avenae. Significant correlations were also found between resistance to Rhopalosiphum padi and Hx levels. Although the concentrations of Hx in whole plants declined during seedling growth, concentrations of Hx in newly‐emerging leaves remained high in plants of all ages, including in the emerging flag leaves of mature plants. When the mean relative growth rate of S. avenae over three days was used instead of rm and the control of environmental conditions was improved, a higher proportion of the variation in aphid performance was explained by Hx concentrations in six cultivars.
An analysis of genetic variation in sugar beet (Beta vulgaris L. using an augmented biparental (ABIP) mating design
Authors: SMITH M. C. , CORNISH M. A. , MACKAY I. J. 
Published: February 2008

SummaryAn augmented biparental (ABIP) mating design was used to investigate the quantitative variation, particularly the dominance variation, for morphological and chemical characters in sugar beet. Diploid O‐type plants were both crossed and selfed and the progeny were grown in a single‐plant randomised field trial. A comparison of the two kinds of family provided tests for both dominance variation and directional dominance effects. Estimates of the narrow heritability were also obtained for each character. Germination problems reduced the size of the final analysis but evidence was obtained of dominance variation and positive directional dominance effects for leaf length, root weight and potassium concentration and, to a lesser extent, sugar concentration. Genetic control of sodium and alpha‐amino nitrogen concentrations appeared to be mostly additive. Hybrid varieties of sugar beet should exploit these directional dominance effects and the more closely varieties approach true F, hybrids the more they will capitalise on these advantages. It is possible that other factors such as epistasis, contamination, competition and seed effects may cause us to under‐ or overestimate the importance of dominance.
Effects of defoliation at different growth stages and in different grain‐filling environments on the growth and yield of spring barley
Authors: JENKYN J. F. , ANILKUMAR T. B. 
Published: February 2008

SummaryThe yield of spring barley grown outside was little affected by the removal of all fully expanded leaves during late tillering or early stem extension but was decreased by defoliation either earlier or later. Removal of all except the top two leaves when 50% of the ears were fully emerged also had relatively little effect on yield but damage was increased if only the flag leaf was retained, especially if the leaves apart from the flag leaf were removed 10 days earlier when the first awns were visible. Defoliation treatments, including those which had little effect on barley grown outside, generally had proportionately greater effects if the plants were moved to a warm glasshouse at the start of grain filling.
A comparison of two large‐scale seed priming techniques
Authors: GRAY D. , ROWSE H. R. , DREW R. L. K. 
Published: February 2008

SummaryLeek seed lots of high (91%) and low (82%) viability were primed in aerated polyethylene glycol (PEG) solutions in Bubble‐columns and by a non‐osmotic priming technique in both 1987 and 1988 and the seeds were then sown in the field. Both methods of priming established a similar seed moisture content during treatment and, in the laboratory, produced seeds with more rapid and uniform germination than untreated seeds, with a greater advantage for Drum compared with Bubble‐column priming in PEG. In the field, both priming techniques gave seedling emergence responses similar to those from priming in PEG by the laboratory‐scale technique on filter paper. Both large‐scale priming methods gave earlier and more uniform emergence than untreated seeds and gave similar or slightly higher levels of seedling emergence, except on one sowing occasion when seeds were stored before sowing followed by sowing into a drying seedbed.
Studies on the frequency distribution of Pythium‐induced cavity spot of carrots
Authors: PHELPS K. , WHITE J. G. , HENN A. J. 
Published: February 2008

SummaryData on Pythium‐induced cavity spot from experimental plots and commercial fields were collated to study the frequency distribution of cavities on carrots. It was shown that cavities tended to occur in clusters with strong evidence that they followed a Polya‐Aeppli distribution rather than the Negative Binomial distribution often associated with clustering. Possible biological interpretations of the Polya‐Aeppli distribution are discussed, also their implications for estimation of inoculum potential and analysis of cavity spot field trials.
Narcissus latent, a virus with filamentous particles and a novel combination of properties
Authors: MOWAT W. P. , DAWSON S. , DUNCAN G. H. , ROBINSON D. J. 
Published: February 2008

SummaryAs previously reported, narcissus latent virus (NLV) has flexuous filamentous particles measuring c. 650 nm × 13 nm, is manually transmissible to Nicotiana clevelandii and Tetragonia expansa, and is transmitted by the aphid Myzus persicae following brief acquisition access periods. In contrast to previous reports the virus particle protein has an apparent mol. wt of c. 45 kD. Moreover, infected cells in N. clevelandii leaves contain cytoplasmic inclusion bodies resembling those of potyviruses. In vitro translation of NLV RNA produced only one major product (mol. wt c. 25 kD) which was not precipitated by antisera to virus particle protein or to cytoplasmic inclusion protein. Antisera to 12 potyviruses and nine carlaviruses failed to react with sap containing NLV particles. Similarly antiserum to NLV particles did not react with particles of seven potyviruses or four carlaviruses.A weak reaction was detected between NLV particles and antiserum to particles of maclura mosaic virus (MMV), a virus which resembles NLV in particle morphology and particle‐protein size, and in inducing pinwheel inclusions. The cytoplasmic inclusion proteins (CIPs) of NLV, MMV and from narcissus plants with yellow stripe symptoms were serologically inter‐related. These proteins were also serologically related to, and had mol. wt similar to, the CIP of members of the potyvirus group. Particles with the size and antigenic specificity of those of NLV were found consistently in narcissus plants with yellow stripe disease.Narcissus latent and narcissus yellow stripe viruses therefore seem to be synonymous and, together with MMV, have properties distinct from those of any previously described virus group.
Analytical pyrolysis‐pattern recognition for the characterisation of leafy spurge (Euphorbia esula L.) biotypes
Authors: EVANS J. O. , TORELL J. M. , VALCARCE R. V. , SMITH G. G. 
Published: February 2008

SummaryCurie‐point pyrolysis‐gas chromatography‐pattern recognition was used to elucidate chemical variations within leafy spurge (Euphorbia spp.). Hierarchical cluster analysis (HCA) readily identified two major clusters corresponding to E. esula and E. cyparissias. The E. esula cluster further separated into three distinct subclusters. Results from principal components analysis (PCA) and fuzzy c‐varieties (FCVPC) pattern recognition were similar, verifying the presence of three biotypes among the E. esula samples studied. It is suggested that analytical pyrolysis in combination with pattern recognition may predict the behaviour of biocontrol agents introduced into fields to control leafy spurge.
A mathematical model describing the combined effect of exposure time and temperature of hot‐water treatments on survival of gladiolus cormels
Authors: ROEBROECK E. J. A. , JANSEN M. J. W. , MES J. J. 
Published: February 2008

SummaryGladiolus cormels of five cultivars were given hot‐water treatments at 50.0°C, 52.5°C, 55.0°C or 57.5°C for different exposure times. Survival of cormels was determined. A mathematical model to describe the combined effect of exposure time and temperature on cormel death is presented. Consequences of these relationships for the practical application of hot‐water treatments to control cormel‐borne Fusarium oxysporum f.sp. gladioli are discussed.
Longevity of pearl millet (Pennisetum glaucum) seeds harvested at different stages of maturity
Authors: RAO N. KAMESWARA , RAO S. APPA , MENGESHA M. H. , ELLIS R. H. 
Published: February 2008

SummaryThe storage potential of seeds harvested at weekly intervals after controlled pollination was studied in three diverse cytoplasmic male sterile pearl millet (Pennisetum glaucum) lines. In the first experiment in 1989, a comparison of p50 (time for viability to decline to 50% during storage) among seeds of the line DSA 105A harvested 14, 21, 28, 35 and 42 days after pollination (DAP), and then stored at 35°C with 15% moisture content or 40°C with 13% moisture content, showed that those harvested 35 DAP had the greatest longevity. In the second experiment in 1990, a comparison of p50 within the lines 5141A and L 67A harvested 28, 35 and 42 DAP, and then stored at 40°C with 13% moisture content, showed that seeds of both lines harvested 42 DAP had the greatest longevity. In both the seasons, and in all three lines, maximum seed longevity (p50) was attained one week after physiological maturity (defined as the end of the grain filling period), which is therefore the optimum time of harvest to obtain good quality seeds for conservation.
Behavioural response of the entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis bacteriophora to oxamyl
Authors: GAUGLER RANDY , CAMPBELL JAMES F. 
Published: February 2008

SummaryInfective juveniles of the entomopathogenic nematode Steinernema carpocapsae show a low level of locomotory activity that is presumed to limit their usefulness as biological insecticides. A 30 μg ml‐1 solution of the carbamate pesticide oxamyl reduced the proportion of nonmobile nematodes by nearly two thirds to 35%, while stimulating a 7.5‐fold increase in sinusoidal movement. This increase in activity did not result in a corresponding increase in host‐finding. Oxamyl treatment did not enhance infective juvenile pathogenicity to Galleria mellonella larvae. At higher concentrations, oxamyl caused aberrant nematode movement and partial paralysis. Heterorhabditis bacteriophora infective juveniles maintain a high level of locomotory activity. Treatment with 30 μg ml‐1 oxamyl increased the proportion of sinusoidal over nonsinusoidal movements, but infective juvenile host‐finding and pathogenicity were significantly reduced. Higher rates impaired movement and induced complete paralysis. We conclude that oxamyl is incompatible with S. carpocapsae and H. bacteriophora. The concept of chemically activating infective juveniles to increased locomotory activity and thereby achieving enhanced efficacy is inconsistent with our results.
Evaluation of entomopathogenic nematodes for control of Cosmopolites sordidus Germar (Coleoptera: Curcilionidae), a pest of bananas in Australia
Authors: TREVERROW N. , BEDDING R. A. , DETTMANN E. B. , MADDOX C. 
Published: February 2008

SummaryApplications of Steinemema carpocapsae All strain in water thickener into cuts or holes made in residual rhizomes of bananas gave significant mortality of Cosmopolites sordidus larvae in the rhizomes. The methods proved suitable for field application and two large scale field trials using S. carpocapsae All and S. carpocapsae NC513 gave acceptable levels of control as measured by Vilardebo's (1973) Co‐efficient of Infestation. Mortality of adult C. sordidus attracted to the application sites on treated rhizomes was observed during these field trials.
Interactions between Chromolaena odorata (Asteraceae) and Pareuchaetes pseudoinsulata (Lepidoptera: Arctiidae)
Authors: MARUTANI M. , MUNIAPPAN R. 
Published: February 2008

SummaryFeeding of Pareuchaetes pseudoinsulata caterpillars caused the leaves of Chromolaena odorata to turn yellow. Leaf yellowing could not be induced either by artificial removal of leaves or by drenching the plant with a solution of excreta from P. pseudoinsulata caterpillars. Yellow leaves appeared tougher but had the same energy level as that of green leaves. The amount of nitrate‐nitrogen was significantly higher in yellow leaves than green leaves. P. pseudoinsulata caterpillars prefer to feed on green leaves. When forced to feed on yellow leaves, they exhibit slow growth and high mortality. Defensive factors in plants attacked by insects seemed to prevent further infestation of plants. In the field, caterpillars on the yellow plants were found during both day and night whereas on green plants they appeared to feed at night and hide in the ground at daytime.
Changes in the hydroxamic acid content of maize leaves with time and after artificial damage; implications for insect attack
Authors: MORSE S. , WRATTEN S. D. , EDWARDS P. J. , NIEMEYER H. M. 
Published: February 2008

SummaryThe dynamics of hydroxamic acids (Hx) in maize plants were examined, along with the effects on this process of artificial leaf damage. The concentration of Hx in maize (cv. LGH) leaves declined rapidly with age, although young emerging tissue did have relatively high levels. The decline was not entirely due to a growth dilution effect, as the total Hx content in leaves also decreased with age. This effect was less pronounced in isolated leaves. The plant hormone abscisic acid (ABA) accelerated the decline in Hx in isolated maize leaves, while indole acetic acid (IAA) had no apparent effect. Artificial leaf damage on growing plants produced a significant increase in the concentration of Hx relative to undamaged controls. The difference was greatest (about 18%) two days after damage, but seemed to be largely due to a slower rate of decline relative to controls. Isolated maize leaves generally showed a much higher level of increase (20 ‐ 40%). The results are generally consistent with the theory that Hx functions as a defence against insect attack.
The effect of maize leaf damage on the survival and growth rate of Rhopalosiphum padi
Authors: MORSE S. , WRATTEN S. D. , EDWARDS P. J. , NIEMEYER H. M. 
Published: February 2008

SummaryTwo different types of artificial leaf damage, crushing and cutting, were assessed for their effects on the growth and survival of Rhopalosiphum padi caged on maize (cv. LG11) leaves. Crushing significantly reduced aphid growth rate by up to 23% and their survival by five to six times, while cutting had no significant effects. Although the area of tissue involved was lower for crushing relative to cutting (c. 5% and 10% respectively), the greater level of cellular damage inflicted by crushing may have resulted in more phytochemical changes. These effects suggest that the feeding of one herbivore guild such as leaf chewers may adversely affect the performance of another, such as phloem feeders.
Responses of micropropagated peach cultivars to thermotherapy for the elimination of prunus necrotic ringspot virus
Authors: STEIN A. , SPIEGEL S. , FAINGERSH G. , LEVY S. 
Published: February 2008

SummaryPeach (Prunus persica (L.) Batsch) shoot‐cultures infected with prunus necrotic ringspot virus (PNRSV) were selected for evaluating the responses of in vitro grown shoots of cvs Hermosa and Summerset to thermotherapy. The survival of shoot‐cultures during thermotherapy was improved by selection of the optimum concentration of 6‐benzylamino purine in the medium and optimum age of shoots for treatment. Alternating high and low temperature thermotherapy regimes were more effective in decreasing virus titre than constant high temperatures. Of the regimes tested, the most effective inhibition of PNRSV combined with a high survival of shoots was obtained by applying 38°C for 16 h in light alternating with 28 CC for 8 h in darkness for 18 days for Hermosa and 22 days for Summerset. Following this treatment 90% of Hermosa and 40% of Summerset shoot‐cultures were virus‐free as determined by enzyme‐linked immunosorbent assay. Relatively large (about 10 mm) apices excised from these shots regenerated into virus‐free plants. The advantage of the in vitro system for thermotherapy is discussed.