Effects of cotton leaf surface alkalinity on feeding ofSpodoptera littoralis larvae

1988 ◽  
Vol 14 (3) ◽  
pp. 839-844 ◽  
Author(s):  
A. Navon ◽  
M. Zur ◽  
Lelia Arcan
Keyword(s):  
Leaf Surface ◽  
Cotton Leaf

Association between Alternaria macrospora and Alternaria alternata, causal agents of cotton leaf blight

1991 ◽  
Vol 69 (12) ◽  
pp. 2603-2607 ◽  
Author(s):  
Yoav Bashan ◽  
Hanna Levanony ◽  
Reuven Or
Keyword(s):  
Gossypium Hirsutum ◽  
Alternaria Alternata ◽  
Leaf Surface ◽  
Gossypium Barbadense ◽  
Cotton Leaf ◽  
Optimal Dosage ◽  
Alternaria Blight ◽  
Cotton Species ◽  
Infested Field ◽  
Blight Disease

The association between Alternaria macrospora and Alternaria alternata, responsible for the development of alternaria blight disease in cotton, was evaluated in artificially inoculated greenhouse plants and in naturally infested field plants. When greenhouse plants were inoculated with suboptimal doses of both pathogens (< 1.2 × 104 spores/mL) infection was greater than when separately inoculated by each pathogen at optimal dosage. In field-grown, naturally infected plants (Gossypium barbadense), both pathogens were found together in more than 40% of the plants. A second field-grown cotton species (Gossypium hirsutum) exhibited infection mainly by either A. alternata or both pathogens together. When both cotton species were naturally infected by both pathogens together, the number of A. alternata spores (either airborne or on the leaf surface) was greater than that of A. macrospora. We propose that A. macrospora together with A. alternata create a disease composite responsible for alternaria blight symptoms in cotton. Key words: Alternaria, cotton diseases, Gossypium barbadense, Gossypium hirsutum.

scholarly journals Simulating droplet motion on virtual leaf surfaces

2015 ◽  
Vol 2 (5) ◽  
pp. 140528 ◽  
Author(s):  
Lisa C. Mayo ◽  
Scott W. McCue ◽  
Timothy J. Moroney ◽  
W. Alison Forster ◽  
Daryl M. Kempthorne ◽  
...  
Keyword(s):  
Leaf Surface ◽  
Spray Coating ◽  
Cotton Leaf ◽  
Droplet Motion ◽  
Thin Film Model ◽  
Pressure Term ◽  
Leaf Surfaces ◽  
Chemical Defect ◽  
Scan Data ◽  
Curvature Driven

A curvilinear thin film model is used to simulate the motion of droplets on a virtual leaf surface, with a view to better understand the retention of agricultural sprays on plants. The governing model, adapted from Roy et al. (2002 J. Fluid Mech. 454, 235–261 ( doi:10.1017/S0022112001007133 )) with the addition of a disjoining pressure term, describes the gravity- and curvature-driven flow of a small droplet on a complex substrate: a cotton leaf reconstructed from digitized scan data. Coalescence is the key mechanism behind spray coating of foliage, and our simulations demonstrate that various experimentally observed coalescence behaviours can be reproduced qualitatively. By varying the contact angle over the domain, we also demonstrate that the presence of a chemical defect can act as an obstacle to the droplet's path, causing break-up. In simulations on the virtual leaf, it is found that the movement of a typical spray size droplet is driven almost exclusively by substrate curvature gradients. It is not until droplet mass is sufficiently increased via coalescence that gravity becomes the dominating force.

SOOTY MOULD DISEASES OF SOME TREES FROM AURANGABAD DISTRICT, MAHARASHTRA (INDIA)

2017 ◽  
Vol 23 (2) ◽  
Author(s):  
NAVALSINGH J. TODAWAT
Keyword(s):  
Surface Area ◽  
Fungal Pathogens ◽  
Leaf Surface ◽  
Severity Of Disease ◽  
Sooty Mould ◽  
Leaf Surface Area

Sooty mould diseases of Tress from Aurangabad district were surveyed. During the survey of tress, 5 species were found infected by fungal pathogens causing sooty mould diseases. Disease is easily identifiable by the presence of a black, velvety growth covering the leaf surface area. The fungus produces mycelium which is superficial and dark grows on the flowers, leaf, stem and sometime on fruits also. The severity of disease depends on the honeydew secretions by insects. The diseases were found to be caused by 5 species of fungi viz. Capnodium anonae, C. ramosum, Capnodium sp., Meliola bangalorensis and Meliola ranganthii.

Leaf surface and endophytic fungi associated with onion leaves and their antagonistic activity against Alternaria porri.

2015 ◽  
Vol 67 (1) ◽  
pp. 1-22 ◽  
Author(s):  
Sobhy I. I. Abdel-Hafez ◽  
Kamal A. M. Abo-Elyousr ◽  
Ismail R. Abdel-Rahim
Keyword(s):  
Endophytic Fungi ◽  
Leaf Surface ◽  
Antagonistic Activity ◽  
Alternaria Porri

INFLUENCE OF GROWTH REGULATORS AND LED IRRADIATORS ON PINE STRAWBERRY ADAPTATION

1970 ◽  
pp. 12-15
Author(s):  
M. G. Markova ◽  
E. N. Somova
Keyword(s):  
Surface Area ◽  
Growth Regulators ◽  
Leaf Surface ◽  
Combined Treatment ◽  
Fragaria X Ananassa ◽  
Leaf Surface Area ◽  
External Conditions ◽  
Light Effects ◽  
Control Version

Work on going through the adaptation stage of rooted micro-stalks comes down to searching for new growth regulators and studying the influence of external conditions, which include, among other things, light effects. The data of 2018-2019 on the effect of growth regulators Siliplant, EcoFus and experimental LED phytoradiators on the adaptation of rooted micro-stalks of garden strawberries (Fragaria x ananassa duch) in vivo are presented. The object of research is rooted micro-stalks of garden strawberries of the Korona variety. It was revealed that, at the adaptation stage of rooted micro-stalks of strawberries, the most effective was the treatment of plants by spraying with Siliplant at a concentration of 1.0 ml/l and the combined treatment with Siliplant and EcoFus at concentrations of 0.5 ml/l: regardless of lighting, the survival rate averaged 99.4 - 99.7%, the leaf surface area increased significantly from 291.85 mm2 to 334.4 mm2. The number of normally developed leaves of strawberry microplants increased significantly after treatment with all preparations from 3.5 to 6.0, 5.8 and 6.5 pcs/plant, and a significant increase in the height of strawberry rosettes was facilitated by treatment with Siliplant and Siliplant together with EcoFus. Regardless of growth regulators, the most effective was the experimental LED phyto-irradiator with a changing spectrum, which contributed to an increase in leaf surface area, height of rosettes and the number of normally developed leaves in strawberry microplants. When illuminated with a flashing phytoradiator, these indicators are lower than in the control version, but not significantly. By the end of the rooting stage, all microplants of garden strawberries corresponded to GOST R 54051-2010.

FEATURES OF THE PRODUCTION PROCESS OF ANCIENT AND MODERN VARIETIES OF WINTER RYE

1970 ◽  
pp. 15-19
Author(s):  
A. A. Torop ◽  
V. V. Chaykin ◽  
E. A. Torop ◽  
I. S. Brailova ◽  
S. A. Kuzmenko
Keyword(s):  
Production Process ◽  
Dry Matter ◽  
Leaf Surface ◽  
Unit Area ◽  
Biomass Accumulation ◽  
Vegetation Period ◽  
Winter Rye ◽  
Total Chlorophyll ◽  
Potential Productivity ◽  
Productivity Potential

We compared peculiarities of the production process of the older and modern(created 80 years after) sorts of winter rye. It is determined that the specific coenotic productivity of a modern sort is 60.6% higher.This increase is due to higher number of productive sprouts per unit area and higher sprout weight. The coenosis of modern sorts is highly resistant to lodging. The modern sort has a 33.5% higher leaf surface index and a 17.7% higher share of the leaves in the upper tier, differing in their erectile orientation in space. As for the content of total chlorophyll in the dry matter of leaves and vagina, the modern sort is inferior to the older by 30.2%during theearing period, and by 17.5%during the milky-wax ripeness period.As for the content of total chlorophyll in the sowing area, the compared sorts were practically the same, but the ratio between chlorophyll a and c was noticeably different. As for the chlorophyll content in stems, in dry matter and in the area of ​​sowing, the modern sort is inferior by1.5 times and more to the older in both observation terms. The sorts differed in the biomass accumulation and its distribution between the parts during the vegetation period. To establish the ear productivity, the older sort used only the current photosynthesis products.In conditions of an unfavorable growth year, the modern sort used previously accumulated by leaves and re-utilized assimilates. The actual and potential productivity of an ear in a modern sort is higher by 77.4 and 68.0%, respectively, but the degree of its vegetative mass supply is lower by 48.6%.Only due to the higher, by 77.4%, utilization of the mass of the sprout, the modern sort binds a greater number of grains in the ear with a higherseparate mass.Since the sharp increase in the ear productivity potential was not accompanied by the same growth of the sprout vegetative mass, the modern sort, in unfavorable conditions for growth, has tensions in the relation system between the sprout vegetative mass and pouring grain. This may be the reason of the unstable achievedyield level.

TUNGAU PADA DAUN MANGGA (Mangifera Indica)

2014 ◽  
Vol 13 (3) ◽  
Author(s):  
Rawati Panjaitan
Keyword(s):  
Life Cycle ◽  
Direct Observation ◽  
Host Plants ◽  
Body Shape ◽  
Leaf Surface ◽  
Mangifera Indica ◽  
Posterior Part ◽  
Mango Leaves

Mites have hostplant specifications or host plants. Mites can be destructive and deadly of which is the host plants a mango crop. Mites on mango crops will cause the leaves yellow and fall off prematurely. This is will lead to the disruption of the productivity of mango. It is necessary for research to identify the mites that infect the mango crop. The method is carried out by direct observation. Mites were taken from the surface of mango leaves later in preservation with several levels of concentration of alcohol, and polyvinyl laktofenol. Then, observed under a microscope and documented for identification purposes. Mites on the leaf surface of manalagi mango (<em>Mangifera indica</em>) found two species, it is <em>Oligonychus</em> sp. and <em>Oligonychus ilicis</em> (Family: Tetranychidae, Superfamily: Tetranychoidea). <em>Oligonychus</em> sp. hallmark is rounded body shape like a spider, with a body is transparent and there are two long seta on posterior part. While <em>Oligonychus ilicis</em> has a characteristic elongated rounded body shape, red, and there is a short posterior seta. <em>Oligonychus</em> sp. and <em>Oligonychus ilicis</em> live as parasites on the surface of mango leaves that can lead to wrinkled leaves, yellow and to fall. <em>Oligonychus</em> life cycle starts from the eggs develop into Nympha and then adult.

Gymnomitrion fissum (Gymnomitriaceae, Marchantiophyta) — a new species with fissured leaf surface from China

2017 ◽  
Vol 51 ◽  
pp. 274-280
Author(s):  
A. D. Potemkin ◽  
Yu. S. Mamontov ◽  
N. S. Gamova
Keyword(s):  
New Species ◽  
Cross Sections ◽  
Cell Walls ◽  
Leaf Surface ◽  
Outer Cell ◽  
Sem Images ◽  
Cell Lumen ◽  
A New Species ◽  
Surface Comparison

Study of selected specimens of Gymnomitrion collected by D. G. Long in Yunnan, China, revealed a new species, G. fissum Mamontov et Potemkin, sp. nov., with a fissured leaf surface. Comparison of SEM images of the leaf surface and leaf cross sections shows that the leaf surface of G. fissum is different from that of other known species with a superficially similar leaf surface, i. e. Mylia taylorii, M. verrucosa s. l. and Trabacellula tumidula. It has fissures around the cell lumen rather than grids and perforations. Outer cell walls of Gymnomitrion fissum are much thicker than in Mylia taylorii, M. verrucosa s. l. and Trabacellula tumidula, and their outer layers tend to be partly or completely caducous. G. fissum is related to the group of species assigned to the former genus Apomarsupella.

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