Distribution of the incident light intensities on over the apple-fruit surface during some days of its growing period in the orchard

The reaction was studied in a circulatory apparatus under a variety of conditions. The sole primary process occurring is C—Cl bond scission. The Cl atoms formed in the primary step, through an abstractive attack on the substrate, generate chlorodifluoromethyl radicals (CF2Cl) All principal reaction products, CF2H2, CF2Cl2, CF2ClCF2Cl, CF2HCF2H, and CF2HCF2Cl, can be accounted for by the combination–disproportionation reactions of the CF2H• and CF2Cl• radicals. The observed strong dependence of the primary quantum yields on the incident light intensities has been ascribed to a rapid substrate-reforming step.

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Changes in the Ultrastructure of the Epicuticular Wax and Postharvest Calcium Uptake in Apples

HortScience ◽

10.21273/hortsci.34.1.121 ◽

1999 ◽

Vol 34 (1) ◽

pp. 121-124 ◽

Cited By ~ 26

Author(s):

Stephane Roy ◽

William S. Conway ◽

Alley E. Watada ◽

Carl E. Sams ◽

Eric F. Erbe ◽

...

Keyword(s):

Calcium Uptake ◽

Structural Changes ◽

Apple Fruit ◽

Epicuticular Wax ◽

Harvest Time ◽

Storage Duration ◽

Ca Uptake ◽

Temperature Scanning ◽

The Relationship ◽

Fruit Surface

Structural changes in the cuticle could be partially responsible for the differences in uptake of infiltrated Ca in apple fruit. We examined the relationship between the surface structure of epicuticular wax of `Golden Delicious' apple and Ca uptake by the fruit. Apples were nontreated or pressure infiltrated with distilled water, or with 0.14 or 0.27 mol·L-1 CaCl2 solutions 2 weeks before optimum harvest time, at optimum harvest, or after 2, 4, or 6 months of storage at 0 °C. Examination of the fruit surface with low-temperature scanning electron microscopy revealed that cracks in the epicuticular wax became wider and deeper as storage duration increased. After 6 months of storage, the cracks extended through the cuticle. Uptake of Ca by the infiltrated fruit was greater after 6 months of storage than after shorter storage intervals. These data indicate that as storage duration increased, epicuticular wax cracks became deeper and Ca uptake by the fruit increased.

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Surface Moisture Induces Microcracks in the Cuticle of ‘Golden Delicious’ Apple

HortScience ◽

10.21273/hortsci.43.6.1929 ◽

2008 ◽

Vol 43 (6) ◽

pp. 1929-1931 ◽

Cited By ~ 27

Author(s):

Moritz Knoche ◽

Eckhard Grimm

Keyword(s):

Relative Humidity ◽

Outer Surface ◽

Apple Fruit ◽

Ambient Atmosphere ◽

Mechanism Of Formation ◽

Cuticular Membrane ◽

Surface Moisture ◽

Golden Delicious ◽

Before And After ◽

Fruit Surface

Formation of microcracks in the cuticular membrane (CM) of epidermal segments (ES) of apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf., ‘Golden Delicious’, ‘Braeburn’, ‘Idared’, ‘Jonagold’, and ‘Topaz’; all grafted on ‘Malling.9’ rootstocks] fruit was studied after exposure of the surface of the ES to water. Potential strain of the CM on the ES was preserved by mounting a stainless steel washer on the fruit surface using an ethyl-cyanacrylate adhesive. Subsequently, ES were excised by tangentially cutting underneath the washer. The number of microcracks in the CM was established by light microscopy before and after a 48-h incubation period in deionized water. Within 48 h, the number of microcracks rapidly increased when the outer surface of ES of ‘Golden Delicious’ apple was exposed to water, but there was essentially no increase in microcracks when exposed to the ambient atmosphere. The occurrence of microcracks depended on the region of the fruit surface and increased from the rim of the pedicel cavity to the calyx. Increasing the relative humidity (greater than 75% relative humidity at 22 °C) above the outer surface of the ES exponentially increased the number of microcracks. Water-induced microcracking was not limited to ‘Golden Delicious’, but also occurred in ‘Braeburn’, ‘Jonagold’, ‘Topaz’, and, to a markedly smaller extent, in ‘Idared’ apple. The mechanism of formation of microcracks in the CM of apple fruit and their role in fruit russeting are discussed.

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Comparative effects of kaolin and calcium carbonate on apple fruit surface temperature and leaf net CO2 assimilation

Journal of Applied Horticulture ◽

10.37855/jah.2015.v17i03.33 ◽

2015 ◽

Vol 17 (03) ◽

pp. 176-180 ◽

Cited By ~ 1

Author(s):

H.L. Alvarez ◽

C.M. Di Bella ◽

G.M. Colavita ◽

P. Oricchio ◽

J. Strachnoy

Keyword(s):

Calcium Carbonate ◽

Surface Temperature ◽

Co2 Assimilation ◽

Apple Fruit ◽

Net Co2 Assimilation ◽

Fruit Surface

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Estimation of apple fruit surface area

New Zealand Journal of Crop and Horticultural Science ◽

10.1080/01140671.1995.9513908 ◽

1995 ◽

Vol 23 (3) ◽

pp. 345-349 ◽

Cited By ~ 34

Author(s):

Murray Clayton ◽

Nevin D. Amos ◽

Nigel H. Banks ◽

R. Hugh Morton

Keyword(s):

Surface Area ◽

Apple Fruit ◽

Fruit Surface

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CELLULOSE FIBERS SHOW PROMISE IN REDUCING SUNBURN INJURY OF `PAULARED' APPLES.

HortScience ◽

10.21273/hortsci.27.6.638a ◽

1992 ◽

Vol 27 (6) ◽

pp. 638a-638

Author(s):

Alvan Gaus ◽

Matthew Rogoyski

Keyword(s):

Vegetative Growth ◽

Corn Starch ◽

Colloidal Suspension ◽

Cellulose Fibers ◽

Apple Fruit ◽

Symptom Expression ◽

Binding Agent ◽

Direct Sunlight ◽

The Third ◽

Fruit Surface

A set of 3 experiments was conducted to determine if cellulose fibers (CF) could reduce the incidence of sunburn injury in `Paulared' apples. Sunburn injury was artificially increased in these experiments by fruit manipulation and removal of shading vegetative growth to expose apples to at least 4 hours of direct sunlight. The 4 treatments applied included an unsprayed control, a commercial binding agent (CBA), a 1% corn starch (CS) colloidal suspension, and a 3% CF suspension that contains CBA and CS. No differences between treatments were found in the first experiment. The CF suspension concentration was increased to 9% for the second experiment. This resulted in uneven CF distribution on the fruit surface and no significant differences between treatments. The third experiment was designed to more precisely determine sunburn symptom expression by delineating the manipulated fruit surface area directly exposed to sunlight prior to treatment. The resulting percent of area that showed a white (bleached) sunburn symptom was significantly less for the apple fruit treated with CF than CBA alone.

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Cold tolerance and winter hardiness in Lolium perenne: II. Influence of light and temperature during growth and hardening

The Journal of Agricultural Science ◽

10.1017/s0021859600057828 ◽

1973 ◽

Vol 80 (2) ◽

pp. 341-348 ◽

Cited By ~ 33

Author(s):

T. Lawrence ◽

J. P. Cooper ◽

E. L. Breese

Keyword(s):

Light Intensity ◽

Cold Tolerance ◽

Lolium Perenne ◽

Water Soluble ◽

Light Conditions ◽

Low Light ◽

Growing Period ◽

Light Intensities ◽

Lower Light ◽

Light Input

SummaryIn the first paper of this series it was shown that Lolium perenne material required hardening periods involving low, but above freezing, temperatures before frost tolerance was achieved. The present experiments show that the light conditions during the hardening and prehardening periods are also important. At both stages a reduction in total light energy reduced subsequent cold tolerance but the relative effects of light intensity and photoperiod differed between the prehardening and hardening treatments. Thus low light input during the hardening period at 2 CC reduced cold tolerance most when given at higher intensities over shorter days (8 h) while during the prehardening growing period at 20 °C the reduction was greatest when the lower light input was given at low intensity over longer days (16 h).Varieties of different climatic origins reacted differentially to the treatments. The Mediterranean variety Fano was particularly adversely affected by low light intensities during hardening and also benefited from higher temperatures during the prehardening growing period. With higher light intensities and higher growth temperatures this Mediterranean variety approached the more northern material in cold tolerance; but as a corollary it was clear that the N. European variety Veja was able to harden under lower light conditions, and lower growing temperatures. The varieties Melle and S. 321 from intermediate latitudes, were intermediate in response.Although water soluble carbohydrate content was increased during the hardening period, except at the lowest light intensity (2·9 W/m2), no simple relationship between the WSC content and the cold tolerance of the different varieties could be detected.The results provide a useful guide to the pre-treatments necessary to discriminate between varieties for cold tolerance in such a way that the results can be correlated with field performance.

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Canopy Size and Light Use Efficiency Explain Growth Differences between Lettuce and Mizuna in Vertical Farms

Plants ◽

10.3390/plants10040704 ◽

2021 ◽

Vol 10 (4) ◽

pp. 704

Author(s):

Theekshana C. Jayalath ◽

Marc W. van Iersel

Keyword(s):

Energy Use ◽

Incident Light ◽

Dry Weight ◽

Biomass Energy ◽

Photon Flux ◽

Light Use Efficiency ◽

Growing Period ◽

Use Efficiency ◽

High Yields ◽

Canopy Size

Vertical farming is increasingly popular due to high yields obtained from a small land area. However, the energy cost associated with lighting of vertical farms is high. To reduce this cost, more energy efficient (biomass/energy use) crops are required. To understand how efficiently crops use light energy to produce biomass, we determined the morphological and physiological differences between mizuna (Brassica rapa var. japonica) and lettuce (Lactuca sativa ‘Green Salad Bowl’). To do so, we measured the projected canopy size (PCS, a morphological measure) of the plants throughout the growing cycle to determine the total amount of incident light the plants received. Total incident light was used together with the final dry weight to calculate the light use efficiency (LUE, g of dry weight/mol of incident light), a physiological measure. Plants were grown under six photosynthetic photon flux densities (PPFD), from 50 to 425 µmol m–2 s–1, for 16 h d–1. Mizuna and lettuce were harvested 27 and 28 days after seeding, respectively. Mizuna had greater dry weight than lettuce (P < 0.0001), especially at higher PPFDs (PPFD ≥ 125 µmol m–2 s–1), partly because of differences in the projected canopy size (PCS). Mizuna had greater PCS than lettuce at PPFDs ≥ 125 µmol m–2 s–1 and therefore, the total incident light over the growing period was also greater. Mizuna also had a higher LUE than lettuce at all six PPFDs. This difference in LUE was associated with higher chlorophyll content index and higher quantum yield of photosystem II in mizuna. The combined effects of these two factors resulted in higher photosynthetic rates in mizuna than in lettuce (P = 0.01). In conclusion, the faster growth of mizuna is the result of both a larger PCS and higher LUE compared to lettuce. Understanding the basic determinants of crop growth is important when screening for rapidly growing crops and increasing the efficiency of vertical farms.

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