Peronospora farinosa f. sp. betae. [Descriptions of Fungi and Bacteria].

1983 ◽  
Author(s):  
S. M. Francis
Keyword(s):  
Geographical Distribution ◽  
Seed Plant ◽  
Systemic Leaf ◽  
Aerial Parts ◽  
Potential Source ◽  
Young Leaves ◽  
Colour Changes ◽  
Second Year ◽  
Seed Crops ◽  
Pale Green

Abstract A description is provided for Peronospora farinosa f. sp. betae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Beta spp., including the cultivated varieties of B. vulgaris subsp. vulgaris, e.g. chard, fodder beet, mangold, red beet, spinach beet and sugar beet. DISEASE: Downy mildew of beet. Typical infection is systemic and the young leaves at the centre of the rosette are attacked. Infected leaves are at first pale green; they fail to expand fully, their colour changes to yellowish green, and they become swollen, brittle and are usually incurred. Conidia are formed in great profusion, first on the under surface of infected leaves but spreading to the upper surface in wet weather. After sporulation the leaves die prematurely. Some leaves are only partly infected; the tip remains healthy and the division between diseased and healthy tissue is sharply defined. Under humid conditions, early in the season, the fungus may cause a non-systemic leaf-spot on young plants. All aerial parts of the seed plant in its second year may become infected. GEOGRAPHICAL DISTRIBUTION: Africa (Kenya, Morocco); Asia (Israel, USSR); Australasia (Australia, N.S.W., Victoria. New Zealand); Europe (widespread); North America (Canada, U.S.A.); South America (Argentina). Note that CMI Map No. 28, ed. 3, 1969, shows records of P. farinosa on Beta, Spinacia and Chenopodium spp. TRANSMISSION: The disease can be transmitted by oospores, perennial mycelium or by continual reinfection from living plants. Oospores, on debris in the ground, are a potential source of inoculum but have only been reported of economic importance on seed crops in France. Seed crops and groundkeepers can provide a source of living inoculum overwinter and this is the most common and economically important source of the fungus (Byford & Hull, 1967). Seed may be contaminated by oospores and mycelium and there is evidence that oospores on imported seed were responsible for the introduction of the disease into Australia (15, 193).

Diaporthe manihotis. [Descriptions of Fungi and Bacteria].

1982 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
South America ◽  
Central America ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Manihot Esculenta ◽  
West Indies ◽  
Severe Attack ◽  
Early Stages ◽  
Young Leaves ◽  
Pale Green

Abstract A description is provided for Diaporthe manihotis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOST: Manihot esculenta. DISEASE: Leaf spot of cassava (46, 64) or sometimes referred to as Phomopsis blight of tapioca (54, 2588). In the early stages of infection the visible symptoms are pale green, watersoaked, small round spots on young leaves and petioles which rapidly enlarge and turn brown. Severe attack leads to defoliation and infection spreading to the stem. Affected areas become shrivelled with numerous pycnidia embedded in the tissue. On severely infected stems the bark starts to peel off gradually leading to partial or total girdling. GEOGRAPHICAL DISTRIBUTION: Africa (Ethiopia, Nigeria); Asia (India); Central America and West Indies (S.E. Dominica); South America (Colombia). TRANSMISSION: Probably by watersplash-dispersed conidia.

Xanthomonas campestris pv. graminis. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
K. E. Reay
Keyword(s):  
Geographical Distribution ◽  
Festuca Arundinacea ◽  
Xanthomonas Campestris ◽  
Natural Infection ◽  
Dactylis Glomerata ◽  
Phleum Pratense ◽  
Vascular Bundles ◽  
Poor Growth ◽  
Young Leaves ◽  
Natural Host Range

Abstract A description is provided for Xanthomonas campestris pv. graminis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Lolium italicum, L. multiflorum, L. perenne, Dactylis glomerata, Festuca pratensis, and Trisetum flavescens. Single cases of natural infection of Agropyron repens, Phalaris arundinacea and Phleum pratense are also recorded (62, 241), but their status in the natural host range is unknown. In inoculation tests (Egli et al., 1975; Egli & Schmidt, 1982) the following were highly susceptible: Alopecurus pratensis, Dactylis glomerata, Festuca arundinacea, F. pratensis, F. rubra, Lolium loliaceum, L. multiforum, L. parabolicae, L. perenne, L. remotum, L. temulentum, Phleum arenarium and P. bertolonii. Showing much less susceptibility were Agrostis alba, Arrhenatherum elatius, Phleum alpinum, P. phleoides, P. pratense, Poa annua, P. compressa, P. fertilis, P. memoralis, P. pratensis and P. trivialis. Leyns et al. (61, 6162) found that Agrosas tenuis and Festuca ovina were moderately susceptible when inoculated. Egli et al. (1975) recorded doubtful symptoms on Hordeum vulgare and Triacum aestivam on inoculation, but consider that they are unlikely to be naturally infected. DISEASE: Bacterial wilt of forage grasses. Symptoms usually first noticed at the heading stage, when young leaves curl and wither, and shoots remain stunted or may die. Other plants will continue to make poor growth and produce small, distorted inflorescences. Chlorotic and necrotic zones form on the older leaves along long stretches of vascular bundles, often extending into the sheaths. Bacterial streaming may be seen under the microscope from the cut ends of vascular bundles of infected tissue mounted in water. GEOGRAPHICAL DISTRIBUTION: CMI Map 533, ed. 1, 1979 lists France, Germany, Switzerland and Wales, to which must be added Scotland (63, 2925), Belgium (61, 4199), Netherlands, Norway (62, 241), and New Zealand (62, 241). Possibly in USA (IL; 61, 5045) though this disease is currently attributed to a Rickettsia- like organism. TRANSMISSION: Within the crop transmission is presumed to be by the blades of mowing machines.

scholarly journals Total phenolic and flavonoid contents and biological activities of Cachrys cristata DC. extracts

2014 ◽  
Vol 66 (3) ◽  
pp. 1117-1123
Author(s):  
Jelena Matejic ◽  
Ana Dzamic ◽  
Tatjana Mihajilov-Krstev ◽  
Vladimir Randjelovic ◽  
Ksenija Mileski ◽  
...  
Keyword(s):  
Salmonella Enteritidis ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Total Phenolic ◽  
Bacterial Strains ◽  
Phenolic Contents ◽  
Aerial Parts ◽  
Potential Source ◽  
Dilution Assay ◽  
Phenolic And Flavonoid

The total phenolic/flavonoid contents and antioxidant potential of the methanol, ethyl-acetate, acetone and water extracts obtained from the aerial parts and fruits of Cachrys cristata DC.(Apiaceae) were compared. The total phenolic contents of the tested extracts were determined using Folin-Ciocalteu?s reagent. The amounts per g of dry plant extract of gallic acid (GA) and quercetin (Qu) ranged between 22.60-166.97 mg, and 8.91-46.02 mg, respectively. The antioxidant activity, expressed as IC50, ranged from 1.784-17.621 mg/mL and from 1.01-3.42 mg L(+)-ascorbic acid (Vitamin C)/g when tested with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ABTS, respectively. The antimicrobial activity of the extracts was investigated by the microwell dilution assay, for the most common human gastrointestinal pathogenic bacterial strains: Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027, Salmonella enteritidis ATCC 13076, Bacillus cereus ATCC 10876, Listeria monocytogenes ATCC15313, Staphylococcus aureus ATCC 25923 and yeast Candida albicans ATCC 10231. The results indicate that C. cristata can be regarded as a potential source of antioxidant and antimicrobial agents.

Microsphaera penicillata. [Descriptions of Fungi and Bacteria].

1968 ◽  
Author(s):  
K. G. Mukerji
Keyword(s):  
North America ◽  
Powdery Mildew ◽  
Geographical Distribution ◽  
World Wide ◽  
Late Summer ◽  
Erysiphe Pisi ◽  
Temperature And Humidity ◽  
Young Leaves ◽  
Dry Seasons

Abstract A description is provided for Microsphaera penicillata. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On species of Alnus, Betula, Syringa, Lathyrus, sweet peas and numerous other hosts (Saknon, 1900; Stevens, 1925; 39: 739; 41: 175) DISEASES: Powdery mildew of alder and lilac. Forms a white to grey floury appearance on the surface of broad leaves of many hard wood trees. It is more prevalent on sweet peas than Erysiphe pisi (CMI Descript. 155) in North America in spring when temperature and humidity are fluctuating. The foliage may be malformed, dropping prematurely or drying out and shrivelling. It is also prevalent on lilac in late summer and autumn, sometimes in dry seasons almost completely covering the foliage, but generally too late in the season to cause serious damage. Young leaves are more susceptible. GEOGRAPHICAL DISTRIBUTION: World-wide on alder and lilac and occasionally occurring on numerous other hosts. Distributed generally in North America and Europe, also reported from Chile, China, India and Japan (Salmon, 1900, 39: 739; 41: 175). TRANSMISSION: Spores wind borne.

Pseudomonas sesami. [Descriptions of Fungi and Bacteria].

1964 ◽  
Author(s):  
A. C. Hayward
Keyword(s):  
United States ◽  
Phaseolus Vulgaris ◽  
East Africa ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Aerial Parts ◽  
Annotated List

Abstract A description is provided for Pseudomonas sesami. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Sesamum orientale (Pedaliaceae). Infects stems, pods, but not the leaves of Phaseolus vulgaris on inoculation. DISEASE: A leaf spot affecting aerial parts of plant. Blackish-brown spots which coalesce may extend along whole length of stem. Angular spots on leaves delimited by veins. Infected capsules blacken. GEOGRAPHICAL DISTRIBUTION: Parts of East Africa; China, Japan, Korea, Bulgaria, Greece, Turkey, Yugoslavia, United States, Brazil (CMI Map 398). TRANSMISSION: Presumably by wind driven rain; on seed, see Noble et al., An Annotated List Of Seed-Borne Diseases, CMI, Kew, 1958, p. 117.

Cryptodiaporthe populea. [Descriptions of Fungi and Bacteria].

1973 ◽  
Author(s):  
C. Booth
Keyword(s):  
Geographical Distribution ◽  
Western Europe ◽  
First Year ◽  
Severe Damage ◽  
North East ◽  
Conidial State ◽  
Wide Range ◽  
East Russia ◽  
Second Year ◽  
Old Trees

Abstract A description is provided for Cryptodiaporthe populea. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Poplar, willow. A wide range of poplar species are more or less susceptible, with members of the tacamahacca and algeros groups principally affected. Populus alba var. pyramidalis is very susceptible in Britain and P. alba and P. tremula are tolerant; complete resistance is unknown in the genus: The fungus has been recorded on cricket bat willow in Belgium. DISEASE: Dothichiza canker, Dorhichiza dieback, poplar canker. The conidial state is the form of this fungus most commonly found associated with the dieback or canker of poplar. The fungus is a wound parasite unable to invade sound bark tissues, although very small wounds, such as scars left by bud scales, may permit infection (38, 341). Infection usually occurs in the winter, when bark moisture and turgor are lowest (36, 673; 37, 684). First signs are a discoloration of the cortex under the bark, which develops to a sunken, dead patch of bark, often at the base of twigs or at the junction of first-year and second-year wood. The lesion may have an unpleasant odour and later develops black, globular, pycnidia on the surface. The lesion may heal over in a single season but it can spread to cause severe damage or death of the host. Injury is believed to be due to toxin formation as well as physical girdling by the canker (35, 797; 38, 103). The crowns of old trees or young plants in nurseries and plantations are mainly affected. The disease may be distinguished from that caused by Valsa sordida Nits. by its larger conidia and larger and less frequent stromata in infected tissues. GEOGRAPHICAL DISTRIBUTION: Europe (all western Europe excluding Portugal, Norway, Yugoslavia, Rumania, Bulgaria, Poland, Estonia, Ukraine and south-east Russia). Near East (Turkey, Cyprus). North America (east Canada, north-east USA). South America (Argentina) (CMI Map 344, ed. 2, 1968). TRANSMISSION: Mainly by airborne splash-dispersed conidia.

Septoria helianthi. [Descriptions of Fungi and Bacteria].

1970 ◽  
Author(s):  
P. Holliday
Keyword(s):  
Helianthus Annuus ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Seed Treatment ◽  
Seed Transmission ◽  
Adaxial Surface ◽  
Young Leaves

Abstract A description is provided for Septoria helianthi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Helianthus annuus, Helianthus grosseserratus and Helianthus rigidus. DISEASE: Leaf spot of sunflower. Yellowish spots up to 1.5 cm develop over the whole lamina, gradually turning necrotic and becoming almost black. The numerous pycnidia are mostly on the adaxial surface. The lesions have a polygonal outline, being sharply delimited by the veins. Infection may begin on the cotyledons and young leaves, spreading to later developing leaves. Severe attacks lead to defoliation and loss in yield. GEOGRAPHICAL DISTRIBUTION: Fairly widespread in E. Europe and the U.S.S.R. in Asia, China, Japan, Australia (Qd.); E. and S. Africa, N. America (CMI Map 468, ed. 1, 1970). TRANSMISSION: Overwintering occurs in host debris. Seed treatment is recommended although seed transmission does not appear to have been demonstrated. Introduction of the fungus into Hungary may have been via seed (43, 2013).

Phaeoramularia angolensis. [Descriptions of Fungi and Bacteria].

1986 ◽  
Author(s):  
P. M. Kirk
Keyword(s):  
Geographical Distribution ◽  
Fruit Drop ◽  
Fruit Spot ◽  
Young Leaves ◽  
Survival Mechanisms

Abstract A description is provided for Phaeoramularia angolensis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Species of Citrus including C. aurantium and C. sinensis. DISEASE: Leaf and fruit spot. In young leaves and fruit a generalized necrosis sometimes forms resulting in defoliation and fruit drop. GEOGRAPHICAL DISTRIBUTION: Africa (Angola, Cameroon, Gabon, Nigeria, Uganda, Zambia, Zimbabwe), Asia (Yemen). TRANSMISSION: Possibly from air borne conidia, survival mechanisms unknown.

Soil organic matter as influenced by straw management practices and inclusion of grass and clover seed crops in cereal rotations

Soil Research ◽  
2003 ◽  
Vol 41 (1) ◽  
pp. 95 ◽  
Author(s):  
D. Curtin ◽  
P. M. Fraser
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Management Practices ◽  
Degree Days ◽  
Straw Management ◽  
Soil C ◽  
Total Soil ◽  
C And N ◽  
Second Year ◽  
Seed Crops

In New Zealand, cereal straw has traditionally been burned to facilitate seedbed preparation for the succeeding crop. Because of concerns over the decline of organic matter and the associated deterioration in soil structure, farmers are interested in incorporating crop residues as a means of maintaining organic matter levels. In a 6-year trial on a Wakanui silt loam on the Canterbury Plains, we evaluated the effects of 3 straw management practices (i.e. straw incorporation, burning of straw, and straw removal) on total and labile soil organic matter. A fourth treatment was included to evaluate the local practice of including seed crops (grass and clover) in cereal rotations. The seed crops were grown every second year, the crop sequence being cereal–ryegrass–cereal–clover–cereal–clover. The rate of straw (wheat) decomposition was determined using a litter bag technique, with the bags being buried at a depth of 15 cm for intervals of up to 19 months. In the straw-incorporated treatment, about 25 t/ha of straw (~11 t C/ha) was returned to the soil during the trial. However, there was no significant effect (P > 0.05) of straw management treatments on total soil C (or N), or on labile organic matter pools, although there was a tendency for higher levels of mineralisable C and N where straw was incorporated. Measured straw decomposition rates were consistent with predictions of the Douglas-Rickman residue decomposition model. Under the relatively warm conditions of the Canterbury Plains (thermal time typically >4000 degree-days per year, calculated as the sum of daily degree-days above a base temperature of 0�C), about three-quarters of incorporated straw decomposed within a year. Of the 11 t C/ha of straw-C incorporated, we estimated that only about 1 t C/ha would remain in the soil at the time of sampling. An increase in soil C by this amount would not be detectable (total soil C was about 55 t/ha in the upper 15 cm). Growing seed crops every second year increased several of the labile organic pools (mineralisable C and N, light fraction C and N, microbial biomass) in the 0–7.5 and 7.5 cm soil layers and this may have beneficial effects (e.g. improved N supply) on the succeeding cereal crop. However, the seed crops did not significantly increase total soil organic matter within the 6 years.

scholarly journals Effect of plant’s alimentation area on productivity of Oregano plants (Origanum vulgare L.) under conditions of a drip irrigation

2020 ◽  
pp. 68-75
Author(s):  
N. V. Pryvedeniuk ◽  
A. P. Shatkovskyi
Keyword(s):  
Leaf Area ◽  
Drip Irrigation ◽  
Growth And Development ◽  
Plant Nutrition ◽  
Aerial Part ◽  
First Year ◽  
Maximum Height ◽  
Origanum Vulgare ◽  
Aerial Parts ◽  
Second Year

Oregano (Origanum vulgare L.) – is a perennial medicinal plant, its medicinal raw material is the aerial part collected in the flowering phase. When laying industrial plantations of oregano, the seedling method of propagation is mainly used, since after germination the plants slowly develop and compete weakly with weeds. The condition for survival of seedlings is high soil moisture, which can be achieved only with its artificial wetting - irrigation. An analysis of the literature indicates that today the issue of the cultivation pattern and nutrition area of oregano in the conditions of drip irrigation is not well understood. The aim of the conducted experimental studies was to establish the influence of the method of growing seedlings and plant’s alimentationon area on the growth and development of oregano under drip irrigation. The main research method is a field experiment, supplemented by analytical and static data processing methods. According to research’s results, it has been established that an increase in the area of plant nutrition contributes to an increase in the mass of the aerial parts and the area of leaves, and also reduces the height of plants during both the first and second years of vegetation. It was proved that the most favorable conditions for plant’s growth and development under the conditions of drip irrigation were in the variant with the largest nutrition area with planting density of 41,7 thousand plants·ha-1 (60x40 cm pattern). The mass of the aerial parts of plants with this method of growing in the first year of vegetation was 110,5-133,0 g ·plant-1 with the largest leaf area – 0,287-0,346 m2·plant-1 and 218,1-328,7 g ·plant-1, 0,568-0,855 m2·plant-1, respectively - in the second year of vegetation. The maximum height of plants – 37,0-37,7 cm in the first year of plant vegetation and 68,5-72,6 cm in the second year of vegetation was established in the variants with the smallest plant nutrition area: with a growing scheme of  60x10 cm (166,7 thousand ·ha-1). The smallest plant’s height in the first year of vegetation was 31,1-33,5 cm, in the second year – 37,5-48,4 cm in the variant of growing scheme 60x40 cm (41,7 thousand plants ·ha-1). When studying the influence of the method of growing seedlings on the mass of the aerial part and the area of leaves, their high parameters were found in variants with the laying of seedlings from spring sowing cassettes, where the mass of the aerial part was 103,8 g / plant with a leaf area of 0,236 m2 ·plant-1. The minimum weight of the aerial part is 92,3 g·plant-1 with a leaf area of 0,210 m2 ·plant-1 was found in variants with seedlings on cassettes from the autumn sowing period.

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