Exposure to low levels of photosynthetically active radiation induces rapid increases in palisade cell chloroplast volume and thylakoid surface area in sunflower (Helianthus annuus L.)

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.

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Influence of canopy microclimate on incidence and severity of dogwood anthracnose

Canadian Journal of Botany ◽

10.1139/b92-134 ◽

1992 ◽

Vol 70 (5) ◽

pp. 1093-1096 ◽

Cited By ~ 22

Author(s):

Dan O. Chellemi ◽

Kerry O. Britton

Keyword(s):

Vapor Pressure ◽

Air Temperature ◽

Photosynthetically Active Radiation ◽

Vapor Pressure Deficit ◽

Disease Incidence ◽

Cornus Florida ◽

Active Radiation ◽

Dogwood Anthracnose ◽

Low Levels ◽

Understory Trees

Incidence and severity of dogwood anthracnose within the interior and exterior canopies of exposed dogwood (Cornus florida L.) trees and canopies of understory trees were recorded over a 53-day period during the summer of 1990. Concurrent measurements of vapor pressure deficit, air temperature, evaporative potential, and photosynthetically active radiation within the canopies were also recorded. Disease incidence was significantly lower in the exterior canopy of exposed trees than in other canopy locations. Disease severity was significantly different among all three canopy locations, with the lowest severity in exterior canopies of exposed trees and the greatest severity in canopies of understory trees. Of the climatic variables measured, evaporative potential provided the most consistent contrast among microclimates at the various canopy locations. Mean evaporative potentials averaged over 6- to 10-day intervals ranged from 0.00 g H2O h−1 in understory and exposed, interior canopies to 0.40 g H2O h−1 in exposed, exterior canopies. Disease incidence and severity were greater in canopies associated with low levels of evaporative potential. Key words: Cornus florida L., dogwood anthracnose, canopy microclimate, evaporative potential.

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Changes in Thylakoid Surface Area when Shade Acclimated Helianthus Annuus L. Chloroplasts are Exposed to High P.F.D.

Current Research in Photosynthesis ◽

10.1007/978-94-009-0511-5_717 ◽

1990 ◽

pp. 3179-3182

Author(s):

Wayne R. Fagerberg

Keyword(s):

Helianthus Annuus ◽

Surface Area ◽

Helianthus Annuus L

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PERFORMANCE AND POTENTIAL OF SOLAR INFRARED TRANSMITTING MULCHES

HortScience ◽

10.21273/hortsci.25.6.625f ◽

1990 ◽

Vol 25 (6) ◽

pp. 625f-625

Author(s):

J. Brent Loy ◽

Otho S. Wells

Keyword(s):

Soil Temperature ◽

Photosynthetically Active Radiation ◽

Infrared Radiation ◽

Canopy Development ◽

Active Radiation ◽

Weed Growth ◽

Soil Temperatures ◽

Low Levels ◽

Leaf Canopy

Experimental mulches which transmit high levels of solar infrared radiation and low levels of photosynthetically active radiation were compared to clear and black polyethylene mulches. Increases in soil temperature under infrared transmitting (IRT) mulches were intermediate between those under black and clear mulch. The IRT mulch with the highest solar transmittance (50%) produced soil temperatures close to those under clear mulch (T = 87%). Early leaf canopy development in muskmelon was enhanced more by both IRT and clear mulches than with black mulch. Minimal weed growth occurred under IRT mulches, but there was severe weed pressure from purslane under clear mulch with no herbicide.

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