Modeling Curled Leaves

2007 ◽  
Author(s):  
Shenglian Lu ◽  
Chunjiang Zhao ◽  
Xinyu Guo ◽  
Changfeng Li
Keyword(s):  
Curled Leaves

Pseudoperonospora humuli. [Descriptions of Fungi and Bacteria].

1983 ◽  
Author(s):  
S. M. Francis
Keyword(s):  
Downy Mildew ◽  
Geographical Distribution ◽  
Systemic Infection ◽  
Humulus Lupulus ◽  
Convincing Evidence ◽  
Cone Production ◽  
Secondary Infections ◽  
Pseudoperonospora Humuli ◽  
Growing Crop ◽  
Curled Leaves

Abstract A description is provided for Pseudoperonospora humuli. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOST: Humulus lupulus. DISEASE: Downy mildew of hops. The first sign of infection, seen early in the year, is the development of spindly, stunted, shoots with pale, crowded and down-curled, leaves. These are known as 'primary basal spikes' and are shoots with a systemic infection developed from mycelium which has overwintered in the rootstock. The undersurfaces of the leaves of these shoots bear large crops of sporangia which in moist and humid conditions can soon spread the disease in the growing crop. Secondary infections may occur on leaves, growing tips, flowers and cones. On the leaves they are seen either as small discrete spots or larger, more angular, brown areas. The diseased shoots arising from secondary infections and depending upon the position of the infected bud are known as 'terminal' or 'lateral' spikes. They resemble basal spikes in appearance. Infection of the flowers can inhibit cone production. If cones do develop, and become infected, the brown spots and lesions of the fungus can make them unsaleable. GEOGRAPHICAL DISTRIBUTION: CMI Map No. 14, ed. 4, 1976, with the addition of Belorussia, Estonia, India, Kinghizia, Kazakhstan, Latvia, Lithuania, Moldavia, Ukraine and Uzebekistan. TRANSMISSION: Ware (1926) demonstrated the presence of mycelium in diseased rootstocks but its significance in the overwintering of the pathogen was not fully recognized until Coley Smith (1962) showed that the primary basal spikes which develop in spring originate from infected buds on the rootstocks. Oospores, which are often produced in abundance, were at one time thought to be responsible for infection of the shoots in spring but there is no convincing evidence to support this theory.

scholarly journals Seasonal Dynamics of Taphrina deformans Inoculum in Peach Orchards

2007 ◽  
Vol 97 (3) ◽  
pp. 352-358 ◽  
Author(s):  
V. Rossi ◽  
M. Bolognesi ◽  
S. Giosuè
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Early Spring ◽  
The Other ◽  
Late Winter ◽  
Parasitic Stage ◽  
Tree Canopies ◽  
Trap Plants ◽  
Second Period ◽  
Curled Leaves

The dynamics of the inoculum of Taphrina deformans were studied during a 4-year period by (i) inspecting curled leaves for the presence of asci, (ii) placing deposition spore samplers within the tree canopies, and (iii) exposing potted peach plants (trap plants). These three approaches produced consistent results. Four main periods characterized the dynamics of the inoculum: the first period coincides with the parasitic stage of the pathogen's life cycle and the other periods with the saprophytic stage. Mid- to late spring (first period) was characterized by the presence of asci on infected leaves which produced and ejected large quantities of ascospores in 96% of the samplings. Rainfall was not necessary for ascospore dispersal, which was favored by air temperature <20°C and relative humidity ≥80% or wetness duration >8 h. In summer and autumn (second period), blastospores were trapped in 54 and 24% of samplings, respectively, with low spore numbers. In the winter (third period), blasto-spores were trapped in the lowest numbers and in only 6% of samplings. In late winter to early spring (fourth period), blastospores were found in 56% of samples, with increasing numbers. Rainfall significantly influenced blastospore dispersal and temperature was correlated with the seasonality found during the saprophytic stage.

scholarly journals Phototropin-mediated perception of light direction in leaves regulates blade flattening

2021 ◽  
Author(s):  
Martina Legris ◽  
Bogna Maria Szarzynska-Erden ◽  
Martine Trevisan ◽  
Laure Allenbach Petrolati ◽  
Christian Fankhauser
Keyword(s):  
Leaf Development ◽  
Light Response ◽  
Auxin Signaling ◽  
Kinase Substrate ◽  
Key Aspects ◽  
Light Capture ◽  
Signaling Components ◽  
Curled Leaves

Abstract One conserved feature among angiosperms is the development of flat thin leaves. This developmental pattern optimizes light capture and gas exchange. The blue light (BL) receptors phototropins are required for leaf flattening, with the null phot1phot2 mutant showing curled leaves in Arabidopsis (Arabidopsis thaliana). However, key aspects of their function in leaf development remain unknown. Here, we performed a detailed spatiotemporal characterization of phototropin function in Arabidopsis leaves. We found that phototropins perceive light direction in the blade, and, similar to their role in hypocotyls, they control the spatial pattern of auxin signaling, possibly modulating auxin transport, to ultimately regulate cell expansion. Phototropin signaling components in the leaf partially differ from hypocotyls. Moreover, the light response on the upper and lower sides of the leaf blade suggests a partially distinct requirement of phototropin signaling components on each side. In particular, NON PHOTOTROPIC HYPOCOTYL 3 showed an adaxial-specific function. In addition, we show a prominent role of PHYTOCHROME KINASE SUBSTRATE 3 in leaf flattening. Among auxin transporters, PIN-FORMED 3,4,7 and AUXIN RESISTANT 1 (AUX1)/LIKE AUXIN RESISTANT 1 (LAX1) are required for the response while ABCB19 has a regulatory role. Overall, our results show that directional BL perception by phototropins is a key aspect of leaf development, integrating endogenous and exogenous signals.

scholarly journals INTERACTION OF NITRAPYRIN, N FORM AND N CONCENTRATION ON TOMATO GROWTH, N CONTENT AND RESIDUAL N CONTENT OF SOIL:SAND MEDIUM

HortScience ◽  
1992 ◽  
Vol 27 (11) ◽  
pp. 1173c-1173
Author(s):  
David N. Sasseville ◽  
Rufus Jones
Keyword(s):  
Nitrogen Content ◽  
Dry Weight ◽  
N Content ◽  
Stunted Growth ◽  
N Concentration ◽  
N Form ◽  
Terminal Buds ◽  
Kg Medium ◽  
Tissue Nitrogen ◽  
Curled Leaves

Tomato cv. 'Show Me' were grown in the greenhouse for six weeks in a 50%;50% (v:v) soil:sand mixture and provided weekly with a quarter-strength Hoagland solution with nitrogen provided as 100%:0% 50%;50% 0%:100% nitrate:ammonium ratios at rates of 0, 10, 20, 40, 80 mg N/kg medium with and without 5 mg/kg nitrapyrin. Nitrapyrin induced plant phytotoxic symptoms of stunted growth, curled leaves and deformed terminal buds. These effects were reduced with increasing amount of applied nitrogen and greater percent of nitrate. A second similar experiment using 0, 80, 160, 240, 320 mg N/kg medium and 1 mg/kg nitrapyrin showed no phytotoxic effects and also induced no significant changes in dry weight, tissue nitrogen content or residual medium nitrogen content regardless of nitrogen treatment. N concentration and N form effects were similar to previously reported research with an accumulation of nitrates in tissues with higher nitrate nutrition.

scholarly journals Comparison of NAA and Carbaryl Petal-fall Sprays on Fruit Set of Apples

1993 ◽  
Vol 3 (4) ◽  
pp. 428-429 ◽  
Author(s):  
Max W. Williams
Keyword(s):  
Side Effects ◽  
Fruit Set ◽  
Apple Trees ◽  
Early Application ◽  
Adverse Side Effects ◽  
Biennial Bearing ◽  
Fruit Thinning ◽  
Curled Leaves

Biennial bearing of apple trees can be overcome either by the use of a blossom chemical thinner or by early application of a postbloom thinner. Carbaryl (Sevin) is a post-bloom fruit-thinning chemical with an effective thinning period of 4 to 5 weeks after bloom. Sevin was compared in 1992 and 1993 with NAA as an early petal-fall spray. Sevin treatments reduced fruit set to one fruit per cluster with no adverse side effects on the foliage. NAA inconsistently reduced fruit set and the remaining fruit were in clusters, The NAA-treated foliage was adversely affected; having small curled leaves. NAA at 10 ppm under-thinned in 1992 and seriously over-thinned in 1993, whereas Sevin treatments were consistent for fruit thinning in both years. Sevin applied at petal-fall or at petal-fall + 7 days effectively reduced fruit set and reduced fruit competition.

scholarly journals The Potential for Green Fluorescent Protein as a Screening Tool in the Production of Haploid Potato

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 775B-775
Author(s):  
Rose E. Palumbo ◽  
Richard E. Veilleux*
Keyword(s):  
Fluorescent Protein ◽  
Leaf Disc ◽  
Recessive Gene ◽  
Kanamycin Resistance ◽  
Leaf Discs ◽  
Diploid Clone ◽  
Green Florescent Protein ◽  
Green Fluorescent ◽  
Double Copy ◽  
Curled Leaves

A hybrid between a highly regenerative diploid clone (BARD 1-3) of Solanum phureja and haploid inducer IVP 101 was transformed with Agrobacterium tumefaciens strain 4404 containing plasmid pHB2892 with genes for green florescent protein (GFP) and kanamycin resistance. Hemizygous primary transformants (To) were produced from three leaf discs: 17 diploid plants from one leaf disc, three and nine tetraploids from the other two leaf discs. GFP expression was observed qualitatively under fluorescence microscopes and quantitatively with a GFP meter. Segregation ratios for tetraploid T1 seedlings fit models for single duplex insertions (35 transgenic: 1 non) or double simplex insertions (15 transgenic: 1 non). Diploid T1 seedlings segregated for deleterious traits: dwarfed size and curled leaves, as well as the GFP transgene. Similar segregation patterns in diploid families implied that all diploids may have been from the same transformation event. The cumulative segregation showed the dwarfed and curled plants fit a single recessive gene ratio (3 normal: 1 mutant), and GFP fit a double-copy insertion ratio (15 transgenic: 1 non). Six T1 selections were free of deleterious traits, consistently high expressers of GFP, and produced fertile pollen.

scholarly journals First Report of Phytoplasmas Associated with the Degeneration Syndrome of Artichoke in Catalonia (Spain)

Plant Disease ◽  
2007 ◽  
Vol 91 (6) ◽  
pp. 769-769
Author(s):  
A. Batlle ◽  
J. Sabaté ◽  
A. Laviña
Keyword(s):  
Nested Pcr ◽  
Pcr Amplification ◽  
Mediterranean Area ◽  
Aster Yellows ◽  
Dna Fragment ◽  
Wilt Virus ◽  
First Time ◽  
Broad Bean Wilt Virus ◽  
Wild Cardoon ◽  
Curled Leaves

Spain is the second largest producer of artichoke (Cynara scolymus L.) in the world with 230,000 tons produced annually. The region of Catalonia, located in northeast Spain, has 3,500 ha dedicated to this crop. Low yield and degeneration anomalies are widespread problems in the Mediterranean area. The degeneration syndrome results in curled leaves and late development of capitulum. The association of this syndrome with different viruses such as Artichoke degeneration virus (ADV), Artichoke latent virus (ALV), Broad bean wilt virus (BBWV), Cucumber mosaic virus (CMV), and many others was not conclusive. Other studies indicated that this phenomenon could be related to a regression of the cultivar toward the species of origin, the wild cardoon (C. cardunculus L. var. sylvestris). The distribution of degenerated plants in the principal artichoke-growing areas of Catalonia together with the presence of plants with normal and degenerated tissues in the same plant suggested the presence of phytoplasmas. Samples from 30 symptomatic and 30 asymptomatic plants of cv. Blanca de Tudela were collected in February of 2006 from different areas of Catalonia and analyzed by PCR amplification of phytoplasma DNA. DNA for PCR analyses was prepared from leaf petioles and midribs according to the Ahrens and Seemüller procedure (1). Nested-PCR was carried out with rRNA primer pairs P1/P7 and fU5/rU3 (2,3). Alternatively, nested-PCR, with primers Tuf 1 f/r in the first step and Tuf AY f/r in the second, amplifying a DNA fragment of the elongation gene Tu of the phytoplasmas belonging to Aster yellows and stolbur groups was conducted (4). Results showed a high correlation between presence of symptoms and phytoplasma detection. Phytoplasmas were detected in 100% of the symptomatic plants (30 of 30) and only in one of the asymptomatic plants. The restriction fragment length profiles of Tuf AY amplicons with HpaII showed two different patterns, the most important belonging to the aster yellows (16SrI) group phytoplasma and the other to the stolbur (16SrXII) group phytoplasma. To our knowledge, this is the first time that phytoplasmas have been detected in artichoke and associated with degeneration of this crop. References: (1) U. Ahrens and E. Seemüller. Phytopathology 82:828, 1992. (2) S. Deng and C. Hiruki. J. Microbiol. Methods 14:53, 1991. (3) K. H. Lorenz et al. Phytopathology 85:771, 1995. (4) B. Schneider et al. Microbiology 143:3381, 1997.

scholarly journals Fine mapping of the BnUC2 locus related to leaf up-curling and plant semi-dwarfing in Brassica napus

2019 ◽  
Author(s):  
Chengwei Huang ◽  
Mao Yang ◽  
Danlei Shao ◽  
Yangming Wang ◽  
Shubei Wan ◽  
...  
Keyword(s):  
Candidate Gene ◽  
Plant Height ◽  
Ssr Markers ◽  
Fine Mapping ◽  
Agronomic Traits ◽  
Leaf Shape ◽  
Planting Density ◽  
Lodging Resistance ◽  
Leaf Trait ◽  
Curled Leaves

Abstract Background Studies of leaf shape development and plant stature have made important contributions to the fields of plant breeding and developmental biology. The optimization of leaf morphology and plant height to improve lodging resistance and photosynthetic efficiency, increase planting density and yield, and facilitate mechanized harvesting is a desirable goal in Brassica napus.Results Here, we investigated a B. napus germplasm resource exhibiting up-curled leaves and a semi-dwarf stature. In progeny populations derived from NJAU5737 and Zhongshuang 11 (ZS11), we found that the up-curled leaf trait was controlled by a dominant locus, BnUC2. We then fine mapped the BnUC2 locus onto an 83.19-kb interval on chromosome A05 using single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers. We further determined that BnUC2 was a major plant height QTL that explained approximately 70% of the phenotypic variation in two BC5F3 family populations derived from NJAU5737 and ZS11. This result implies that BnUC2 was also responsible for the observed semi-dwarf stature. The fine mapping interval of BnUC2 contained five genes, two of which, BnaA05g16700D (BnaA05.IAA2) and BnaA05g16720D, were revealed by comparative sequencing to be mutated in NJAU5737. This result suggests that the candidate gene mutation (BnaA05g16700D) in the conserved Degron motif GWPPV (P63S) was responsible for the BnUC2 locus. In addition, investigation of agronomic traits in a separation population indicated that plant height, main inflorescence length, and branching height were significantly reduced by BnUC2, whereas yield was not significantly altered. Our findings may provide an effective foundation for plant type breeding in B. napus.Conclusions Using SNP and SSR markers, a dominant locus (BnUC2) related to up-curled leaves and semi-dwarf stature in B. napus has been fine mapped onto an 83.19-kb interval of chromosome A05 containing five genes. The BnaA05g16700D (BnaA05.IAA2) is inferred to be candidate gene responsible for the BnUC2 locus.

scholarly journals MATERNAL CARE IN THE NEOTROPICAL HARVESTMAN BOURGUYIA ALBIORNATA (ARACHNIDA: OPILIONES): OVIPOSITION SITE SELECTION AND EGG PROTECTION

Behaviour ◽  
2002 ◽  
Vol 139 (11-12) ◽  
pp. 1509-1524 ◽  
Author(s):  
Glauco Machado ◽  
Paulo Oliveira
Keyword(s):  
Maternal Care ◽  
Oviposition Site ◽  
Generalist Predators ◽  
Oviposition Site Selection ◽  
Egg Protection ◽  
The Mean ◽  
One Year ◽  
Reproductive Events ◽  
Number Of Individuals ◽  
Curled Leaves

AbstractFemales of the harvestman Bourguyia albiornata oviposit almost exclusively inside the tube formed by the curled leaves of the bromeliad Aechmea nudicaulis. Oviposition is not correlated with rainfall or with temperature, but is negatively correlated with the number of individuals of A. nudicaulis emitting flowers. Because the inflorescence stalk occupies the tube of leaves of flowering bromeliads, oviposition site is not available for ovigerous females. During one year, 83.6% of the females produced only one egg-batch and the remaining produced two or three batches. The mean number of eggs per batch along successive reproductive events decreased significantly. A field experiment in which females were removed from the nest bromeliad showed that less than 7% of the unprotected eggs survived beyond two weeks. In a control in which females were maintained over the eggs, predators attacked only one egg-batch. Ants were the most important egg predators, and at the study site at least 20 species nest and/or forage in A. nudicaulis. Intense predation on eggs by generalist predators may be an important pressure promoting parental care in Neotropical harvestmen.

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