scholarly journals Endophytic Isaria javanica pf185 Persists after Spraying and Controls Myzus persicae (Hemiptera: Aphididae) and Colletotrichum acutatum (Glomerellales: Glomerellaceae) in Pepper

Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 631
Author(s):  
Roland Bocco ◽  
Moran Lee ◽  
Dayeon Kim ◽  
Seongho Ahn ◽  
Jin-Woo Park ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Myzus Persicae ◽  
Leaf Surface ◽  
Petri Dish ◽  
Tween 80 ◽  
Leaf Damage ◽  
Colletotrichum Acutatum ◽  
Bottom Part ◽  
Insecticidal Efficacy ◽  
Leaf Surface Area

This study endeavored to sustainably control aphids and anthracnose after spraying endophytic Isaria javanica pf185 under field conditions. Under two different tents; one batch of seedlings was sprayed with a 107 conidia/mL I. javanica pf185 suspension; while another was sprayed with 0.05% Tween 80® in distilled water. Six leaf discs from the top; middle; and bottom part of the plant canopy were weekly collected and placed on moistened filter paper in a Petri dish for insecticidal and antifungal bioassays against Myzus persicae and Colletotrichum acutatum. Differences were noticed from the 18th day after spraying with mortality (86.67 ± 0.57% versus 36.67 ± 0.64%) and leaf damage (13.45 ± 0.03% versus 41.18 ± 0.06%) on fungus-treated and controlled, respectively. The corrected insecticidal efficacy was 20.43, 39.82, 72.32, 66.43 and 70.04%, while the corrected fungicidal efficacy was 26.07, 38.01, 53.35, 29.08 and 41.81% during five successive weeks. A positive correlation was evident between insecticidal efficacy and relative humidity (r2 = 0.620) and temperature (r2 = 0.424), respectively. No correlation was found between antifungal activity and relative humidity (r2 = 0.061) and temperature (r2 = 0), respectively. The entomopathogenic fungus survived on leaf surface area and in tissues after spraying.

scholarly journals Evapotranspiration from Spider and Jade Plants Can Improve Relative Humidity in an Interior Environment

2016 ◽  
Vol 26 (6) ◽  
pp. 803-810 ◽  
Author(s):  
Eric W. Kerschen ◽  
Caleb Garten ◽  
Kimberly A. Williams ◽  
Melanie M. Derby
Keyword(s):  
Relative Humidity ◽  
Surface Area ◽  
Leaf Surface ◽  
Indoor Environments ◽  
Photosynthetic Pathway ◽  
Light Conditions ◽  
Interior Spaces ◽  
Leaf Surface Area ◽  
Chlorophytum Comosum ◽  
Spider Plant

Plants in the interiorscape have many documented benefits, but their potential for use in conjunction with mechanical heating, ventilation, and air conditioning (HVAC) systems to humidify dry indoor environments requires more study. In this research, evaporation and evapotranspiration rates for a root medium control, variegated spider plants (Chlorophytum comosum), and green jade plants (Crassula argentea) were measured over 24 hours at 25% and 60% relative humidity (RH) and 20 °C to generate data for calculation of the leaf surface area and number of plants necessary to influence indoor humidity levels. Evaporation and evapotranspiration rates were higher for all cases at 25% RH compared with 60% RH. At 25% RH during lighted periods, evapotranspiration rates were ≈15 g·h−1 for spider plants and 8 g·h−1 for jade plants. Spider plants transpired during lighted periods due to their C3 photosynthetic pathway, whereas jade plants had greater evapotranspiration rates during dark periods—about 11 g·h−1—due to their crassulacean acid metabolism (CAM) photosynthetic pathway. A combination of plants with different photosynthetic pathways (i.e., C3 and CAM combination) could contribute to greater consistency between evapotranspiration rates from day to night for humidification of interior spaces. Using the measured data, calculations indicated that 32,300 cm2 total spider plant leaf surface area, which is 25 spider plants in 4-inch-diameter pots or fewer, larger plants, could increase the humidity of an interior bedroom from 20% RH to a more comfortable 30% RH under bright interior light conditions.

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.

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.

scholarly journals Protective Antifungal Activity of Plantago major Extract Against the Phytopathogenic Fungi Phytophthora cinnamomi, Diplodia corticola and Colletotrichum Species

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 94
Author(s):  
Cláudia Ferreira ◽  
Rui Oliveira
Keyword(s):  
Antifungal Activity ◽  
Secondary Metabolites ◽  
Plant Extracts ◽  
Phytophthora Cinnamomi ◽  
Fungal Infections ◽  
Petri Dish ◽  
Phytopathogenic Fungi ◽  
Colletotrichum Acutatum ◽  
Lower Probability ◽  
Plantago Major

Synthetic fungicides for crops protection raise environmental and human concerns due to accumulation in edible vegetables, showing significant toxicity to humans, and in soil, groundwater and rivers, affecting ecological balance. In addition, they are prone to the development of resistant strains because of the single target-based mechanism of action. Plant extracts provide attractive alternatives, as they constitute a rich source of biodegradable secondary metabolites, such as phenols, flavonoids and saponins, which have multiple modes of antifungal action and a lower probability of the development of resistant fungi. This work has the objective of identifying plant extracts with antifungal activity, aiming to contribute to food safety and sustainable agricultural practices. We selected a saponin-containing plant, Plantago major, and extracted secondary metabolites with 50% (v/v) ethanol, dried by evaporation, and dissolved in water. For antifungal activity, the phytopathogenic fungi Colletotrichum acutatum, Colletotrichum gloeosporioides, Colletotrichum godetiae, Colletotrichum nymphaeae, Diplodia corticola and Phytophthora cinnamomi were selected because they affect fruits and vegetables, such as strawberry, almond, apple, avocado, blueberry and chestnut trees. The aqueous extract was incorporated into PDA medium at different concentrations and mycelial discs were placed in the center of each Petri dish. Growth was measured as the radial mycelial growth at 3, 6, and 9 days incubation at 25 °C in the dark. The maximum growth inhibition (32.2%) was obtained against P. cinnamomi with 2000 µg/mL extract followed by C. gloeosporioides (25.7%) on the sixth day and by C. godetiae and C. nymphaeae (21.1%) on the ninth day. Results show that P. major presents antifungal activity in all phytopathogenic fungi tested and the extract can be used to protect important crops, by inhibiting the development of fungal infections and promoting food security and a sustainable agriculture.

Particle size, leaf pubescence and condition of humidity at leaf surfaces are key factors determining the retention of volcanic ash on crop foliage.

2021 ◽  
Author(s):  
Noa Ligot ◽  
Benoît Pereira ◽  
Patrick Bogaert ◽  
Guillaume Lobet ◽  
Pierre Delmelle
Keyword(s):  
Particle Size ◽  
Surface Area ◽  
Leaf Surface ◽  
Volcanic Risk ◽  
Chilli Pepper ◽  
Leaf Pubescence ◽  
Leaf Surfaces ◽  
Plant Foliage ◽  
Leaf Surface Area ◽  
Ash Deposit

<p>Volcanic ashfall negatively affects crops, causing major economic losses and jeopardising the livelihood of farmers in developing countries where agriculture is at volcanic risk. Ash on plant foliage reduces the amount of incident light, thereby limiting photosynthesis and plant yield. An excessive ash load may also result in mechanical plant damages, such as defoliation and breakage of the stem and twigs. Characterising crop vulnerability to ashfall is critical to conduct a comprehensive volcanic risk analysis. This is normally done by describing the relationship between the ash deposit thickness and the corresponding reduction in crop yield, i.e. a fragility function. However, ash depth measured on the ground surface is a crude proxy of ash retention on plant foliage as this metrics neglects other factors, such as ash particle size, leaf pubescence and condition of humidity at leaf surfaces, which are likely to influence the amount of ash that stays on leaves.</p><p>Here we report the results of greenhouse experiments in which we measured the percentage of leaf surface area covered by ash particles for one hairy leaf plant (tomato, Solanum lycopersicum L.) and one hairless leaf plant (chilli pepper, Capsicum annuum L.) exposed to simulated ashfalls. We tested six particle size ranges (≤ 90, 90-125, 125-250, 250-500, 500-1000, 1000-2000 µm) and two conditions of humidity at leaf surfaces, i.e. dry and wet. Each treatment consisted of 15 replicates. The tomato and chilli pepper plants exposed to ash were at the seven- and eight-leaf stage, respectively. An ash load of ~570 g m<sup>-2 </sup>was applied to each plant using a homemade ashfall simulator. We estimated the leaf surface area covered by ash from pictures taken before and immediately after the simulated ashfall. The ImageJ software was used for image processing and analysis.</p><p>Our results show that leaf coverage by ash increases with decreasing particle size. Exposure of tomato and chilli pepper to ash ≤ 90 μm always led to ~90% coverage of the leaf surface area. For coarser particles sizes (i.e. between 125 and 500 µm) and dry condition at leaf surfaces, a significantly higher percentage (on average 29 and 16%) of the leaf surface area was covered by ash in the case of tomato compared to chilli pepper, highlighting the influence of leaf pubescence on ash retention. In addition, for particle sizes between 90 and 500 µm, wetting of the leaf surfaces prior to ashfall enhanced the ash cover by 19 ± 5% and 34 ± 11% for tomato and chilli pepper, respectively.</p><p>These findings highlight that ash deposit thickness alone cannot describe the hazard intensity accurately. A thin deposit of fine ash (≤ 90 µm) will likely cover the entire leaf surface area, thereby eliciting a disproportionate effect on plant foliage compared to a thicker but coarser deposit. Similarly, for a same ash depth, leaf pubescence and humid conditions at the leaf surfaces will enhance ash retention, thereby increasing the likelihood of damage. Our study will contribute to improve the reliability of crop fragility functions used in volcanic risk assessment.</p>

scholarly journals Growth and productivity of wheat plants under drought in the critical phase of ontogenesis

2021 ◽  
Vol 29 ◽  
pp. 35-40
Author(s):  
O. I. Zhuk ◽  
O.O. Stasik
Keyword(s):  
Triticum Aestivum ◽  
Winter Wheat ◽  
Surface Area ◽  
Leaf Surface ◽  
Triticum Aestivum L ◽  
Grain Number ◽  
Plant Weight ◽  
Inhibition Of Growth ◽  
Critical Phase ◽  
Leaf Surface Area

Aim. The goal of this work was to study the effect of drought in the critical phase of ontogenesis on the growth and productivity of breed winter wheat plants (Triticum aestivum L.). Methods. Wheat plants of cultivars Darunok Podillya and Podolyanka were grown under optimal nutrition and well-water conditions until the earing-flowering phase, after that the experimental plants were transferred to drought regime for 8 days, after that the optimal water supply was restored to the end of vegetation. During the experiment, the leaf surface area, the mass of internodes and ear were determined. Ripened plants were analyzed according to the structure of the yield. Results. It was established that the effect of drought in the critical phase of ontogenesis the earing-flowering caused to the decreasing in leaf surface area, mass of internodes, ear, mass and number of grains in the ear and plant, weight of 1000 grains. Conclusions. Water deficit in the soil in the critical phase of earing-flowering led to a decrease in the productive of breed winter wheat plants due to the inhibition of growth of ear, decreasing grain number and the mass of ear and grains. Keywords: Triticum aestivum L., internode, ear, productivity, drought.

scholarly journals Влияние элементов технологии возделывания винограда на урожай и КПД ФАР клона 337 сорта Каберне-Совиньон в условиях Западного предгорно-приморского района Крыма

2019 ◽  
pp. 117-121
Author(s):  
Alexander Dikan ◽  
Domnica Kashirina ◽  
Irina Ryff
Keyword(s):  
Surface Area ◽  
Photosynthetically Active Radiation ◽  
Leaf Surface ◽  
Coastal Region ◽  
Maximum Efficiency ◽  
Cabernet Sauvignon ◽  
Efficiency Coefficient ◽  
Active Radiation ◽  
Strong Linear Correlation ◽  
Leaf Surface Area

Приводятся результаты трехлетних исследований по клону 337 сорта Каберне-Совиньон в Западном предгорно-приморском районе Крыма. Показано влияние различной нагрузки на куст (11, 17 и 22 глазка) и зеленых операций (чеканка побегов, нормирование урожая, удаление листьев в зоне гроздей с восточной стороны) на величину урожая и коэффициент полезного действия (КПД) фотосинтетически активной радиации (ФАР). Установлено, что максимальная величина КПД ФАР была 0,52% при нагрузке на куст в две лозы плодоношения без последующих зеленых операций. Изменение КПД ФАР на 93,4% зависит от изменения площади листовой поверхности куста. Между КПД ФАР и урожаем винограда с куста существует сильная линейная корреляционная связь и регрессионная зависимость. Изменение массы урожая винограда с куста на 99,9% зависит от изменения площади листовой поверхности куста и КПД ФАР. Увеличенная нагрузка до 17-22 глазков при обрезке будет способствовать наиболее рациональному использованию ресурсов продуктивности кустов клона 337 сорта Каберне-Совиньон в Западном предгорно-приморском районе Крыма.The paper summarizes results of a three-year study on clone 337 of ‘Cabernet Sauvignon’ cultivar in the western piedmont-coastal region of Crimea. The paper demonstrates the influence of various bush loads (11, 17 and 22 eyes) and green operations (shoot trimming, harvest regulation, leaf removal in the bunch area on the eastern side) on the yield size and efficiency coefficient of photosynthetically active radiation. It was found that the maximum efficiency of photosynthetically active radiation made 0.52% with the bush load of two fruiting canes without subsequent green operations. The 93.4% variance of the efficiency coefficient of photosynthetically active radiation is dependent on leaf surface area variations of the bush. There is a strong linear correlation and regressional relationship between the efficiency of photosynthetically active radiation and the yield of grapes per bush. The 99.9% increase of the yield per bush weight depends on the change in the leaf surface area of the bush and the efficiency coefficient of photosynthetically active radiation. Increasing the load up to 17-22 buds when pruning will contribute to the most rational use of bush productivity resources of clone 337 of ‘Cabernet Sauvignon’ in the western piedmont-coastal region of Crimea.

scholarly journals Effects of essential oils from thyme, cinnamon and clove on mycelial growth of Colletotrichum acutatum

2010 ◽  
Vol 25 (2) ◽  
pp. 151-156 ◽  
Author(s):  
Natasa Duduk ◽  
Aleksa Obradovic ◽  
Mirko Ivanovic
Keyword(s):  
Essential Oils ◽  
Mycelial Growth ◽  
Petri Dish ◽  
Control Treatment ◽  
Colletotrichum Acutatum ◽  
Dependent Manner ◽  
Cinnamon Oil ◽  
Volatile Phase ◽  
Vitro Effect

Effects of the volatile phase of thyme, cinnamon and clove essential oils on Colletotrichum acutatum were investigated. Mycelial disc was placed in the center of the Petri dish (V=66 ml) containing PDA. Different volumes of either non- or ethanol-diluted essential oils were placed on the inner side of the dish cover to obtain final concentrations of 153, 107, 76, 46, 15, 14, 12, 11, 7.6, 3.82, 1.53, 0.153 and 0.0153 ?l/L of air. The dishes were sealed with Parafilm and incubated in up-side-down position. After 7 days of incubation, mycelial growth was recorded by measuring the colony diameter. If no mycelial growth was recorded, the disc was transferred to a new PDA plate in order to evaluate whether the activity was either fungistatic or fungicidal. Mean growth values were obtained and then converted to inhibition percentage of mycelial growth compared with the control treatment. All the tested essential oils inhibited mycelial growth of C. acutatum in the dose dependent manner. Mycelial growth was totally inhibited by thyme oil in the concentration of 76 ?l/L of air. The same results were obtained by cinnamon and clove oil in the concentration of 107 ?l/L of air. Thyme and cinnamon oil had fungicidal effect in concentrations of 107 and 153 ?l/L respectively. The results obtained provide evidence on the antifungal in vitro effect of the tested essential oils as potential means for the control of C. acutatum.

scholarly journals Predicting the allometry of leaf surface area and dry mass

2009 ◽  
Vol 96 (2) ◽  
pp. 531-536 ◽  
Author(s):  
Karl J. Niklas ◽  
Edward D. Cobb ◽  
Hanns-Christof Spatz
Keyword(s):  
Surface Area ◽  
Leaf Surface ◽  
Dry Mass ◽  
Leaf Surface Area
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