bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of fungicides on the populations of Colletotrichum and other fungi in bark of coffee*
Authors: GIBBS J. N. 
Published: February 2008

SUMMARYThe effects of copper, captafol and Tuzet, applied to coffee in early season (January to April) and in other programmes continuing through the long rains (January to July), on the bark populations of Colletotrichum cofleanum Noack. (the pathogenic CBD strain and the saprophytic ccm, cca and ccp strains), Phoma spp., Fusarium stilboides Wollenw. and a Phomopsis sp. were investigated on branch material from field experiments in Kenya in 1968 and 1969 by a plating technique which estimated sporulating capacity (s.c.)Fungicide application initially caused a non‐specific reduction in s.c., Tuzet being the most effective. With the onset of the long rains this general reduction was not maintained, although during the period between the long and short rains the levels of many fungi in sprayed plots were still below those in the unsprayed control. In contrast, the s.c. of Phoma in plots sprayed with copper and of Phomopsis in those sprayed with Tuzet were higher than on unsprayed plots. The S.C. of the CBD strain was below that in the control only in plots sprayed with captafol.Effects were still evident after the short rains. Some early‐season programmes of all three fungicides increased the s.c. of the CBD strain while continuing programmes of copper and captafol reduced its S.C. relative to that on unsprayed trees. Differences in S.C. at this time were related to infection in the early crop a few weeks later.The initial antisporulent effect of a fungicide appears less important than its persistence and its effect on bark colonization by the different fungi. Early‐season sprays of copper, formerly used to control CBD, may have contributed to an increase in disease hazards by affecting the primary level of the pathogen.
The effects of topping and plant population on dry matter synthesis and distribution in Brussels sprouts
Authors: JONES L. H. 
Published: February 2008

SUMMARYThe effects of topping at different dates, and of different plant populations on dry‐matter production and distribution in Brussels sprouts were studied. Total dry‐matter production per unit area was unaffected by either topping or density. Leaf area was decreased by topping, resulting in a temporary increase in net assimilation rate. Topping resulted in a redistribution of dry matter; that which would have formed new stem and leaf tissue was directed into sprout production.Increasing plant density did not affect the distribution of dry matter but increased the number of smaller sprouts. The apparent optimum plant spacing in this series was 21×21 in (53×53 cm). At maturity assimilation approximately balances respiration.
Some effects, especially on yield, of artificially defoliating sugar beet
Authors: DUNNING R. A. , WINDER G. H. 
Published: February 2008

SUMMARYThe effects of completely defoliating sugar beet at different dates from May to October were examined in four years. In each year there were plots given the usual nitrogen fertiliser application to the seedbed, and also in two of the years plots given no nitrogen.At harvest in mid‐November, minimum root weights followed defoliation in July or August, but defoliation in August or later gave minimum sugar contents. When nitrogen was applied to the seedbed sugar yields were smallest after August defoliation; in the absence of nitrogen, July defoliation gave the lowest sugar yields, root yield being smaller but sugar content usually greater than with nitrogen. Up to 40% of the sugar yield was lost by July or August defoliation and late defoliation increased some of the impurities in the root juice. Yields, and recovery from defoliation, were greater with nitrogen than without. Partial defoliation in May had relatively little effect on yield. Defoliation affected the incidence of virus yellows differently in different years.
The diurnal periodicity and cycle of behaviour of the adult cabbage root fly (Erioischia brassicae)
Authors: HAWKES C. 
Published: February 2008

SUMMARYAdult cabbage root fly (Erioischia brassicae (Bouché)) exhibited a diurnal periodicity in behaviour. Trapping tests indicated that the flies fed from hedgerow flowers in the morning, visited the crop in the early afternoon and returned to the hedges in the late afternoon. In the laboratory the flies also showed a cyclical pattern in behaviour. Feeding preceded oviposition by 3 days and this was reflected in the field by a relative increase in the movement of females away from the hedges and to the crop when they became gravid. The diurnal periodicity and the cycle in behaviour of males was similar to that of the females, indicating that some of the flies' movement was non‐appetitive.The tendency of flies to stay for most of the day at hedges resulted in progressive declines in the numbers captured with increasing distances from hedges.
Evaluation of fungicides for the control of Verticillium wilt (V. dahliae) of strawberry
Authors: JORDAN V. W. L. 
Published: February 2008

SUMMARYThe treatment of soil or plants before planting, in September 1969, significantly reduced Verticillium wilt on strawberry in the following season. One application of benomyl or thiabendazole (both 0–5% a.i.) at 6728 l/ha to soil 24 h before planting, dusting roots with formulated benomyl powder (50% a.i.) at planting, or a combination of both benomyl dust + drench treatments were effective. However, although the double treatment gave the most disease control in 1970, plants from the soil‐drench treatments gave the highest yields.Residual effects of the 1969 applications were still evident in 1971 from increased vigour, lack of wilt and high yield, especially with the benomyl treatments.
Feeding and the uptake of phosphamidon by two strains of Myzus persicae (Sulz.) on radish plants
Authors: HALIMIE M. A. , FORD J. B. 
Published: February 2008

SUMMARYIntraspecific differences in the uptake of solutions containing phosphamidon, enclosed in Parafilm membranes, have previously been demonstrated in Myzus persicue. This paper shows that similar differences also occur when the aphids are fed on treated plants. Uptake from phosphamidon‐contaminated plants is reduced though the effect was quantitatively different in the two strains of aphid studied. The depression in the level of feeding was related to the concentration of insecticide applied to the plant.
Sclerotinia minor on lettuce: progress of an epidemic
Authors: JARVIS W. R. , HAWTHORNE B. T. 
Published: February 2008

SUMMARYAnalyses of disease progress curves of lettuce drop, caused by Sclerotinia minor, indicate that early infected plants sometimes provide inocula for later secondary spread within the crop, there sometimes being evidence of plant‐to‐plant spread. It is suggested that primary infections are attributable to aerially dispersed ascospores, produced by germinating sclerotia which are soil‐borne, and that secondary plant‐to‐plant spread is associated with mycelial inocula.
Investigations on fungicides: XIV. Fungitoxicity of N‐(2,2,2–trichloro‐1–methoxyethyl)‐formamide and related compounds
Authors: CARTER G. A. , SUMMERS L. A. , WAIN R. L. 
Published: February 2008

SUMMARYFrom a study of forty compounds related to the systemic fungicide N,N'‐bis(1–formamido‐2,2,2–trichloroethyl)‐piperazine, known as triforine (CELAW524), it was found that a new compound, N‐(2,2,2–trichloro‐1–methoxyethyl)‐formamide, controls Erysiphe graminis on wheat when applied to the roots in sand. A number of N‐(2,2,2–trichloro‐1–aryloxyethyl)‐form‐amides and alkyl N‐(2,2,2–trichloro‐1–arylaminoethyl)‐carbamates protect broad beans against Uromyces fabae and wheat against Erysiphe graminis; some of these formamides show slight activity when applied to plant roots.
Take‐all in spring‐sown cereals under continuous cultivation: disease progress and decline in relation to crop succession and nitrogen
Authors: SHIPTON P. J. 
Published: February 2008

SUMMARYIncidence and severity of the take‐all disease in spring wheat and spring barley caused by Gaeumannomyces graminis (syn. Ophiobolus graminis) were studied during seven years of monoculture.The fungus apparently survived for much longer periods in the soil under non‐susceptible break‐crops than previously recorded. The incidence and severity of infection increased progressively with each successive cereal crop from initially low levels to a maximum within 3–7 years, which was followed by a progressive but limited decline in the disease. Spring wheat was more susceptible to take‐all than spring barley and the development of take‐all decline (TAD) was recorded earlier in the sequences of wheat than of barley crops. Nitrogen did not influence the disease until the point of maximum incidence and severity, when it caused a reduction in disease levels in addition to that associated with TAD. Factors influencing the time of onset and the rate of development of take‐all and of TAD are discussed and possible explanations for TAD are suggested.
Further experiments on photosynthesis and translocation in wheat
Authors: LUPTON F. G. H. 
Published: February 2008

SUMMARYA model is deveolped relating photosynthesis taking place in successive layers of the canopy of a wheat crop to the intensity of the radiation incident on the crop, the elevation of the sun, and to the angle to the horizontal and photosynthetic area of ears, leaves and leaf sheaths. The validity of the model is tested by comparing the rate of photosynthesis, pattern of translocation and solid geometry of a semi‐dwarff wheat (TL 365a/25) with those of a variety of conventional height (Cappelle‐Deprez). The model gives realistic estimates of crop yield and indicates that the greater yield of the semi‐dwarf selection is caused by faster photosynthesis, despite less photosynthetic surfaces of ears and leaves. It also indicates that selection for erect leaves may lead to further increases in yield.
The effect of replacing potassium by sodium on cation uptake and transport to the shoots in four legumes and Italian ryegrass
Authors: WHITEHEAD D. C. , JONES L. H. P. 
Published: February 2008

SUMMARYWhite clover, red clover, lucerne, sainfoin and Italian ryegrass were grown in a series of culture solutions in which 0, 25, 50, 75 and 100% of the potassium was replaced by sodium. In the shoots, the potassium: sodium ratios indicated selectivity for potassium which decreased in the order: sainfoin>lucerne>red clover>white clover > Italian ryegrass. In the roots only sainfoin showed selectivity for potassium: with the other species the ratio of potassium to sodium in the roots was similar to that in the other species the ratio of potassium to sodium in the roots was similar to that in the culture solution. All species showed selective transport of potassium to the shoots in preference to sodium: this was least in Italian ryegrass and white clover and greatest in sainfoin, which in contrast to other species also showed restricted transport of potassium to the shoots. Replacement of potassium by sodium slightly increased the magnesium concentration in the shoots but had no effect on the calcium concentration.
Attempts to define and mimic the effects of pollen on the development of lesions caused by Phoma betae inoculated onto sugarbeet leaves
Authors: WARREN R. C. 
Published: February 2008

SUMMARYExpanding lesions resulted when conidia of Phoma betae Frank, mixed with rye pollen, were inoculated on to sugarbeet leaves by a standard technique. Conidia without pollen generally caused non‐expanding necrotic spots; these could be made to spread later by covering them with pollen or orange juice, but not with water.Germ‐tube growth was quicker on water agar than on sugarbeet leaves. Pollen extract stimulated germ‐tube growth on leaves 10 h after inoculation and resulted in the production of knots of hyphae overlying areas where intercellular hyphae could be discerned and where expanding lesions developed.Some inorganic salts mimicked the stimulatory effect of pollen on germtube growth on agar slides, but only a mixture of hexose sugars with boric acid reproduced the effect of pollen on both numbers and size of expanding lesions caused by P. betae on sugarbeet leaves, and numbers of expanding lesions caused by Botrytis cinerea Pers. ex Fr. on bean leaves.
Infection of stored celery plants by Centrospora acerina
Authors: DAY J. R. , LEWIS B. G. , MARTIN SUSAN 
Published: February 2008

SUMMARYChlamydospores in tissue near the bases of plants and in attached soil particles were the main form of inoculum of Centrospora acerina (Hartig) Newhall found on celery plants prepared for storage. Most of these spores remained ungerminated for several weeks but subsequently formed germtubes, terminal appressoria and infection‐pegs, which usually penetrated the plant surface through either the intact cuticle or damaged areas. For several weeks after the beginning of storage the plants were highly resistant to infection. During this time, appressoria failed to penetrate the intact cuticle and, if the fungus entered through damaged areas, hyphal growth in tissue was suppressed. Infection was often found to be associated with abrasion or splitting of the cuticle in commercially stored plants and, in experiments, deliberate damage enhanced the probability of infection. The development of the disease was much slower at 2 d̀C than at 15 d̀C.
Systemic action of benomyl against late‐wilt disease of maize.
Authors: SABET K. A. , SAMRA A. S. , ABDEL‐RAHIM M. F. 
Published: February 2008

SUMMARYBenomyl (methyl‐I‐(butyl carbamoyl)‐2‐benzimidazole carbamate) at 2.5 to 100 ppm completely inhibited the growth in vitro of Cephalosporium maydis Samra, Sabet & Hingorani, the causal fungus of late‐wilt of maize. In pot experiments, late‐wilt was controlled by applications equivalent to 10 ppm benomyl/unit wt dry soil at sowing but not by applications 30 days after sowing or by seed treatments (dusts and dips). A fungitoxic substance was detected in benomyl‐treated soil, planted with maize, 120–150 days after treatment and for 150–180 days in unplanted soil. Sap expressed from maize grown in benomyl‐treated soil was also fungitoxic, especially that from the roots and distal parts of the leaf blades.In the field, soil applications of benomyl to 10 kg/feddan (4200 m2) failed to control late‐wilt. Tests indicated little fungitoxicity in the sap of maize plants 25 days after sowing.
Strain‐genotype interaction of tobacco mosaic virus in tomato
Authors: PELHAM J. 
Published: February 2008

SUMMARYThe symptoms and virus content of isogenic tomato genotypes differing by three tobacco mosaic virus (TMV) resistance factors, Tm‐I, Tm‐2 and Tm‐22, were studied in relation to various isolates of TMV and four strains were identified. The common strain induced no symptoms on plants with any of the factors for resistance, one strain caused symptoms on Tm‐I plants, one on Tm‐2 plants and one on both Tm‐I and Tm‐2 plants and also on Tm‐I Tm‐2 plants. No strain induced symptoms on Tm‐22 plants.The gene, Tm‐I, was found to be dominant or incompletely dominant for preventing symptom development but was recessive or intermediate for limiting virus multiplication of the common strain. Both Tm‐2 and Tm‐22 were dominant for a hypersensitive response to the common strain. Virus multiplication was temperature‐dependent. The background or varietal genotype did not affect virus multiplication.A systemic necrosis of Tm‐22 plants occurred only when heterozygous Tm‐22 was not protected by other factors against specific strains of TMV.The complexity of the host genotype, pathogen genotype and environment interactions are outlined and the exploitation of the resistance factors in tomato breeding discussed.
Serological relationship and detection of bean common and bean yellow mosaic viruses in agar gel
Authors: UYEMOTO J. K. , PROVVIDENTI R. , SCHROEDER W. T. 
Published: February 2008

SUMMARYMicroprecipitin tests demonstrated a distant serological relationship between intact virus particles of BCMV and BYMV. Antiserum titres of 2048–4096 and 16–128 (reciprocals of dilution end‐points) were found for homologous and heterologous antigens, respectively. Cross‐reactivity, however, was not obtained in agar immunodiffusion tests when the antigens, in purified preparations or crude infective sap, were treated with pyrrolidine or when the reactants were placed in agar gels containing sodium dodecyl sulphate. Only homologous antigens produced a precipitin line; homologous antiserum titre was 16.In comparative immunodiffusion trials, single‐radial‐diffusion tests (antiserum incorporated in agar) were much more sensitive than double‐diffusion tests for detecting low virus concentrations.Analyses of virus proteins by polyacrylamide‐gel electrophoresis demonstrated that coat protein of each virus was composed of a single polypeptide chain with a molecular weight of 35000.
Effects of growth regulators on fruit abscission in oil palm, Elaeis guineensis
Authors: CHAN K. W. , CORLEY R. H. V. , SETH A. K. 
Published: February 2008

SUMMARYBy delaying harvest of fruit bunches of the oil palm Elaeis guineensis Jacq., an increase in their oil content can be obtained, but this is accompanied by increased harvesting costs and lower oil quality, as the number of detached fruit increases. Treatment of ripening bunches with auxins, gibberellic acid, or ethephon retards fruit abscission, and harvest can be delayed by up to 5 days without increase in the number of detached fruit. Indications are that oil yield might increase by more than 5% during this period, without change in harvesting costs or oil quality.
Cucumber black root rot caused by Phomopsis sclerotioides
Authors: EBBEN MARION H. , LAST F. T. 
Published: February 2008

SUMMARY Phomopsis sclerotioides was proved to be a primary parasite attacking cucumber roots. Black pseudosclerotial and pseudostromatal lesions occurred more commonly at temperatures of c. 20 oC but at 10 oC unspecific light brown lesions predominated. Damage done by P. sclerotioides was minimal at soil temperatures of c. 20 oC, the aerial dry weights of parasitized plants, as percentages of those of the healthy controls, changing from c. 15% to c. 95% as soil temperatures increased from 12 to 20 oC.Root lesions were associated with root loss and decreased shoot growth. Severe attacks on young plants resulted in stunted growth and small, intensely green leaves. With less severe or later attacks, growth was initially indistinguishable from that of plants growing in uninfested soils until the rate of leaf senescence suddenly increased; these foliar symptoms temporarily simulated attack by vascular wilt fungi. Both sets of foliar symptoms were associated with appreciable yield losses.
The effect of a few days of rain on the distribution of common scab (Streptomyces scabies) on young potato tubers
Authors: LAPWOOD D. H. , ADAMS M. J. 
Published: February 2008

SUMMARYAt Woburn, Beds, in 1967, potato tubers formed and grew in dry soil except after rain between 23 and 26 June. At lifting, Majestic tubers were severely and uniformly scabbed, except for distinct bands free from lesions. The position of the bands differed depending on the date when tubers started to form; they were further from the stolon attachment when tubers formed early and nearer it when tubers formed late.Samples taken in June and July showed that the scab‐free band and the late June rain were related. From 25 June to 1 July the soil was probably wet enough to prevent Streptomyces scabies infection, but only one or two tuber internodes remained free from infection; they were the internodes that began to expand about a week before the rain. Internodes that formed while the soil was wet became scabbed, showing they were still susceptible to S. scabies after the soil had dried again.Recent work on lenticel formation has suggested a hypothesis to explain these results.
The fate of carboxin, benomyl and thiabendazole in seed‐ and soil‐treated plants, as shown by in vitro and in vivo bioassays on some epiphytic yeasts
Authors: GROSS Y. , KENNETH R. 
Published: February 2008

SUMMARYThe yeast, Sporobolomyces roseus, when added to leaves of barley and pea seedlings seed‐ and soil‐treated with carboxin, benomyl or thiabendazole (TBZ), sporulated little or not at all from both sides of the first leaves. Second leaves of barley and third of pea gave similar results. Tests in vivo showed that all three chemicals reduced sporulation of S. roseus at lower concentrations than they did growth, and also delayed sporulation. Leaves from benomyl‐ or TBZ‐treated plants inhibited the growth of sensitive test organisms (S. roseus, Leucosporidium scottii and Aureobasidium pullulans), on agar: it is considered that fungitoxic substances are excreted from both faces of leaves of barley and pea treated with these chemicals.Leaves from carboxin‐treated plants, however, did not inhibit sensitive test organisms (S. roseus, L. scottii and Ustilago hordei), so their inhibitory action in vivo is deemed to result from hormonal imbalance in treated plants: carboxin‐treated barley plants were greener than control plants, no guttation occurred on leaves, and stomata tended to remain open; treated barley and pea were more sensitive to drought than were controls. Carboxin‐treated barley and pea plants sprayed with the cytokinin antagonist, abscisic acid, behaved as did plants without carboxin. It is considered likely that carboxin affects the epiphytes by creating a leaf surface incapable of sustaining them, possibly through dryness.
Growth of helminthosporia on media containing the fungicide benomyl and the assay of benomyl using Botrytis cinerea
Authors: GREENAWAY W. 
Published: February 2008

SUMMARYA bioassay using Botrytis cinerea detected 0–05 ppm benomyl in potato dextrose agar. Nine species of Cochliobolus, fourteen of Drechslera, four of Helminthosporium and five of Pyrenophora tolerated the presence of benomyl to the same extent, and grew on agar plates containing 40 ppm of the compound.
Control of potato cyst‐nematode, Heterodera rostochiensis, in sandy loam, by Du Pont 1410 (S‐methyl l‐(dimethylcarbamoyl)‐N‐[(methylcarbamoyl) oxy] thioformimidate) applied to the soil at planting time
Authors: WHITEHEAD A. G. , TITE D. J. , FRASER JANET E. 
Published: February 2008

SUMMARYWhen applied to heavily infested sandy loam soil at planting time, as little as 5 ppm Du Pont 1410 (5‐methyl I‐(dimethylcarbamoyl)‐N‐[(methylcar‐bamoyl) oxy] thioformimidate) in pots, or 2–5 ppm in field plots, effectively controlled potato cyst‐nematode, Heterodera rostochiensis Woll., and greatly increased the growth and yield of susceptible potatoes. Dipping the shoots of potted King Edward potatoes once in aqeuous solution containing 2000 ppm did not control potato cyst‐nematode. Nematode control was not increased when 2 or 4 kg a.i./ha was sprayed on the foliage of young Pentland Crown potatoes growing in soil already treated with the nematicide.
The effect of seed weight on the early growth and nodulation of white clover
Authors: MYTTON L. R. 
Published: February 2008

SUMMARYThe results of growing, in agar culture, nodulated and un‐nodulated white clover seedlings from three seed‐weight categories, and the subsequent growth of selected plants in soil in pots, are reported.Seed‐weight variations greatly influenced plant growth, made substantial differences in nodulation parameters and nitrogen fixation, and contributed appreciably to the observed variability. The relationship of such effects to nitrogen fixation and the relevance to breeding for superior symbiosis are discussed.The growth of plants, as determined by agar culture technique, was not predictive of their subsequent performance in the soil in pots, and restricting seed weight variations did not improve the prediction. The importance of such effects and the relevance of tube culture to breeding work are discussed.