Histopathology of Albugo tragopogonis on stems and petioles of sunflower

1999 ◽  
Vol 77 (1) ◽  
pp. 175-178
Author(s):  
H Krüger ◽  
A Viljoen ◽  
P S Van Wyk
Keyword(s):  
Cell Division ◽  
Key Words ◽  
Helianthus Annuus ◽  
Systemic Infection ◽  
Infected Tissue ◽  
Tissue Integrity ◽  
Callose Formation ◽  
Stem Lesions ◽  
Lignin Deposition

Stem lesions in sunflower caused by Albugo tragopogonis (Pers.) S.F. Gray developed individually from primary infections and did not result from a systemic infection. Cell division and callose formation were not observed, but weak lignin deposition occurred in infected tissues. Hyphae occurred intercellularly in stems in the cortex, cambium, vascular rays, and pith. In petioles parenchymatous tissue was heavily colonized in contrast to lightly colonized collenchymatous hypodermis. The middle lamellae of cells in infected tissue were dissolved, and cells degenerated and eventually collapsed. Stem infections lead to deterioration of tissue integrity, weakening of stems, and finally to lodging of stems (breaking over).Key words: Albugo tragopogonis, Helianthus annuus, histopathology, stem lodging.

THE EFFECT OF GAMMA STERILIZATION AND ITS EFFECT ON MICROSCOPIC STRUCTURE OF DEEP FROZEN DOG SKULL

2018 ◽  
pp. 37-40
Author(s):  
Phuong Thao Tien Nguyen ◽  
Anh Hung Tran ◽  
Van Tam Le ◽  
Huu Thao Phung ◽  
Phan Quynh Anh Nguyen
Keyword(s):  
Structural Change ◽  
Gamma Radiation ◽  
Gamma Irradiation ◽  
Key Words ◽  
Bone Matrix ◽  
Infected Tissue ◽  
Microscopic Structure ◽  
Bacteriological Examination ◽  
Microscopic Scale

Objective: To evaluate the effect of gamma sterilization and its effect on microscopic structure of deeply frozen dog skull. Subjects and methods: 50 pairs of dog skull fragments have the same size,which were taken symmetrically through the midline of the skull, were divided into two lots. Evident lot consisting of 50 pieces are just deeply frozen, not irradicated. Experimental lot which was composed of 50 pieces were deeply frozen and exposed to 25kGy of gamma radiation. Afterwards, to evaluate the effect of gamma sterilization and compare the alter of bone matrix between lot groups. Results: After gamma irradiation, all dog skull fragments were negative with bacteriological examination. In microscopic scale, no difference was found between the two lots and there was no structural change in the irradiated fragments of all dog skull. Conclusion: Gamma irradiation with 25 kGy: (i) It has the ability to kill bacteria completely in the type of bacteria commonly infected tissue. (ii) It does not alter the structure of dog skull in microstructures. Key words: dog skull, gamma, sterilize

Early symptom development in lodgepole pine seedlings infected with Endocronartium harknessii

1990 ◽  
Vol 68 (2) ◽  
pp. 270-277 ◽  
Author(s):  
Eric A. Allen ◽  
P. V. Blenis ◽  
Y. Hiratsuka
Keyword(s):  
Pinus Contorta ◽  
Rust Fungus ◽  
Infected Tissue ◽  
Cortical Cells ◽  
Subsequent Formation ◽  
Early Symptom ◽  
Pine Seedlings ◽  
Endocronartium Harknessii ◽  
Periderm Formation ◽  
Lignin Deposition

Six-week-old Pinus contorta seedlings were inoculated with spores of the western gall rust fungus Endocronartium harknessii. Of 660 seedlings inoculated, 174 showed early symptoms and were sampled for histological observation in the 7 weeks following inoculation. Pigmentation of epidermal cells was the first externally visible response to infection, generally occurring 14–28 days after inoculation. Developing symptoms were extremely variable, ranging from little or no visible response to severe necrosis. The appearance of external symptoms was largely due to changes occurring in underlying infected cortical cells such as the production of phenolic compounds, necrophylactic periderm, or necrotic tissue. Intercellular lignin deposition was observed in infected tissue and was thought to be associated with necrophylactic periderm formation. Suppression of normal exophylactic periderm development was evident in virtually all infected tissue zones. Infection of the vascular cambium occurred as early as 21 days after inoculation and resulted in the subsequent formation of distorted xylem tracheids typical of gall tissue.

Host range of Puccinia xanthii and postpenetration development on Xanthium occidentale

1993 ◽  
Vol 71 (7) ◽  
pp. 959-965 ◽  
Author(s):  
Louise Morin ◽  
Bruce A. Auld ◽  
John F. Brown
Keyword(s):  
Key Words ◽  
Host Range ◽  
Weed Control ◽  
Biological Weed Control ◽  
Controlled Environment ◽  
Globe Artichoke ◽  
Disease Symptoms ◽  
Severity Of The Disease ◽  
Stem Lesions ◽  
Slow Growing

In glasshouse studies, small necrotic foliar flecks developed on globe artichoke, calendula, slender thistle, and winged slender thistle following inoculation with basidiospores of the microcyclic rust Puccinia xanthii. Fourteen inoculated cultivars of sunflower developed various types of symptoms: small necrotic and chlorotic flecks, underdeveloped telia, and small swollen petiole and stem lesions. Xanthium spinosum developed very slow-growing telia. In controlled environment studies, the four Xanthium spp. comprising the Noogoora burr (cocklebur) complex in Australia were highly susceptible to infection by P. xanthii. Maximum disease severity was observed after rust telia and X. occidentale plants were exposed to a dew period of 24 h. Less disease symptoms were observed in plants exposed to shorter (3, 6, 12 h) or longer (36 h) dew periods. Plants inoculated with several loads of inoculum (exposure to four inoculum plates) were less diseased than plants inoculated with fewer inoculum loads. Infected plants began to develop disease symptoms 5 days after inoculation, when grown at 25 °C. Infected plants developed very few small chlorotic flecks and no disease symptoms when grown at 10 and 40 °C, respectively. The flecks produced on plants kept at 10 °C developed into telia when plants were transferred to a glasshouse (25 °C). Repetitive inoculations of plants for 1 month increased the overall severity of the disease and this resulted in a reduction in plant height. Key words: Xanthium, host range, Puccinia xanthii, biological weed control.

Effects of temperature and pathogen isolate on laboratory screening of soybean for resistance to Sclerotina sclerotiorum

1991 ◽  
Vol 71 (2) ◽  
pp. 347-352 ◽  
Author(s):  
Berlin D. Nelson ◽  
Theodore C. Helms ◽  
Ilhan Rural
Keyword(s):  
Glycine Max ◽  
Key Words ◽  
Sclerotinia Sclerotiorum ◽  
Lesion Length ◽  
Laboratory Screening ◽  
Glycine Max L ◽  
Soybean Resistance ◽  
Effects Of Temperature ◽  
Stem Lesions ◽  
Relative Differences

The effects of temperature and pathogen isolate on laboratory screening of soybean (Glycine max. L.) for resistance to Sclerotinia sclerotiorum were investigated. The screening procedure used excised stems from 5-wk-old plants. Temperature and isolate significantly affected the length of stem lesions on 15 and 10 cultivars, respectively. At 15 °C, lesions were significantly shorter, but there was no difference in lesion length between 20 and 25 °C. One of the isolates caused significantly shorter lesions. There were significant differences among cultivars, but there were no temperature × cultivar or isolate × cultivar interactions. Choice of isolate and temperature between 15 and 25 °C, therefore, should not affect the relative differences among cultivars when screened for resistance using the excised stem method. Maple Presto, Maple Arrow and Maple Ridge were the most resistant of 19 cultivars evaluated. Key words: Soybean, resistance, temperature, isolate, Sclerotinia sclerotiorum

Identification of bacteria isolated from roots of sunflower (Helianthus annuus) cultivated in a French soil

1991 ◽  
Vol 37 (12) ◽  
pp. 971-974 ◽  
Author(s):  
Jacques Fages ◽  
Benoit Lux
Keyword(s):  
Key Words ◽  
Helianthus Annuus ◽  
Azospirillum Lipoferum ◽  
Agrobacterium Radiobacter ◽  
Gram Negative ◽  
Helianthus Annuus L ◽  
Nitrogen Fixers ◽  
Identification Of Bacteria

The bacterial microflora of the rhizoplane and roots of sunflower (Helianthus annuus L.) grown in a French soil was examined. Gram-negative, oxidative isolates were dominant, among which Agrobacterium radiobacter and Pseudomonas vesicularis were the most common. Only 4 of the 45 isolates were nitrogen fixers (acetylene reducers), and they all belonged to the Azospirillum lipoferum species. Key words: sunflower, rhizoplane, Gram-negative isolates.

Floral organ initiation and development in wild-type Arabidopsis thaliana (Brassicaceae) and in the organ identity mutants apetala2-1 and agamous-1

1994 ◽  
Vol 72 (3) ◽  
pp. 384-401 ◽  
Author(s):  
Wilson Crone ◽  
Elizabeth M. Lord
Keyword(s):  
Arabidopsis Thaliana ◽  
Cell Division ◽  
Key Words ◽  
Floral Organ ◽  
Tissue Differentiation ◽  
Main Stem ◽  
Wild Type ◽  
Cell Numbers ◽  
Organ Identity ◽  
Component Cell

The flowers of Arabidopsis thaliana (Brassicaceae) were examined for histological events during organ initiation and later development. An inflorescence floral plastochron of the main stem raceme was used as a basis for the timing and staging of developmental events. Sepals, petals, stamens, and carpels in wild-type Landsberg erecta Arabidopsis are distinguishable as primordia in terms of cell division events associated with initiation, size, and component cell numbers. Flower organogenesis in the organ identity (homeotic) mutants apetala2-1 and agamous-1 was compared with that of the wild type. In both mutants, each whorl of floral organs initiates much like the wild type and only subsequently produces visibly altered organs with mosaic features. The flower organ identity mutants achieve their mature phenotypes by alterations in tissue differentiation that occur after initiation and early primordial development. Key words: Arabidopsis, apetala2-1, agamous-1, plastochron, homeosis, flower.

Isolation and characterization of a mycovirus from Plasmopara halstedii

1992 ◽  
Vol 70 (9) ◽  
pp. 1734-1737 ◽  
Author(s):  
D. E. Mayhew ◽  
A. L. Cook ◽  
T. J. Gulya
Keyword(s):  
Molecular Weight ◽  
Key Words ◽  
Helianthus Annuus ◽  
Downy Mildew ◽  
Type A ◽  
Uv Absorbance ◽  
Plasmopara Halstedii ◽  
Isolation And Characterization ◽  
Virion Surface

A virus was isolated from Plasmopara halstedii, the causal agent of sunflower downy mildew. The virus contained two species of ssRNA with molecular weight (MW) of 1.05 × 106 and 0.53 × 106. One polypeptide with a MW of 37.5 × 103 was associated with whole virus. Purified preparations consisted of two components, the top component consisting primarily of empty shells. The A260/A280 UV absorbance ratio for the bottom component ranged from 1.25 to 1.35. The partially purified virions were isometric, approximately 32 nm in diameter, and had projections of approximately 4 nm on the virion surface. This virus may be related to the type A virus in Sclerophthora macrospora. Key words: mycovirus, downy mildew, Helianthus annuus.

RESPONSE OF EARLY-MATURING SUNFLOWER HYBRIDS TO ROW SPACING AND PLANT DENSITY

1990 ◽  
Vol 70 (4) ◽  
pp. 1169-1171 ◽  
Author(s):  
G. H. GUBBELS ◽  
W. DEDIO
Keyword(s):  
Key Words ◽  
Helianthus Annuus ◽  
Plant Height ◽  
Oil Content ◽  
Plant Density ◽  
Growth Habit ◽  
Row Spacing ◽  
Normal Height ◽  
Early Maturing ◽  
Plant Densities

Two early-maturing sunflower hybrids, Sunwheat 101 and MRS 34, with shorter than normal height and a narrower growth habit were grown at 30- and 60-cm row spacings and three plant densities at each row spacing in the 1986 and 1987 seasons at Morden, Manitoba. There were no differences in achene yield or oil content between row spacings. Plant height and oil content of achenes increased with increase in plant density, while achene weight decreased. Achene yield of both hybrids increased as plant density increased from 55 000 to the 74 000 plants ha−1 density, then remained relatively constant to 148 000 plants ha−1.Key words: Oilseed sunflower, Helianthus annuus L., plant row spacing, plant density

Residual effects of ethametsulfuron on succeeding broadleaf crops

1995 ◽  
Vol 75 (4) ◽  
pp. 941-943
Author(s):  
D. A. Wall
Keyword(s):  
Solanum Tuberosum ◽  
Key Words ◽  
Helianthus Annuus ◽  
Solanum Tuberosum L ◽  
Residual Effects ◽  
Navy Bean ◽  
Dry Bean ◽  
Crop Tolerance ◽  
Potato Yields ◽  
Fagopyrum Esculentum Moench

The response of dry bean (Phoseolus vulgaris L.), buckwheat (Fagopyrum esculentum Moench.), potato (Solanum tuberosum L.) and sunflower (Helianthus annuus L.) to soil residues of ethametsulfuron was determined. Buckwheat and sunflower exhibited moderate to severe injury 4 wk after planting; navy bean, buckwheat, sunflower and potato yields were unaffected in the cropping year after ethametsulfuron application. Key words: Sulfonylurea, crop tolerance, yield

scholarly journals Kemampuan Prospektif Fusan FP4 dalam Memproduksi Inulinase dan Profil Pertumbuhannya

2018 ◽  
Vol 9 (1) ◽  
pp. 25-30
Author(s):  
Wijanarka Wijanarka ◽  
Ika Anggraini
Keyword(s):  
Cell Division ◽  
Key Words ◽  
Incubation Time ◽  
Growth Profile

Fusan FP4 is one type fused materials derived from intraspecific fusion of Pichia manshurca. The fused materials have superior capabilities compared with other materials, especially in producing inulinase enzyme (E.C. 3.2.1.7). The aims of the study are to determine the production of the enzyme inulinase of fusan FP4 and the growth profile formed. Growth can be detected by the addition of size and cell division. Growth measurements of fusan FP4 was carried out for 24 hours and observation and sampling was done every 6 hours for 24 hours. Observations of growth are conducted qualitatively by using a spectrophotometer, while the production of inulinase done using DNS method. The results of this study showed that the highest inulinase production was 1.948 U/ml and occurred at log phase with 6 hours of incubation time (t6) to 12 hours (t12). Key words: inulinase, Fusan FP4, log phase, P. manshurca.

Sign in / Sign up

Export Citation Format

Share Document