scholarly journals Benzyladenine as A Chemical Thinner for `McIntosh' Apples. II. Effects of Benzyladenine, Bourse Shoot Tip Removal, and Leaf Number on Fruit Retention

2000 ◽  
Vol 125 (2) ◽  
pp. 177-182 ◽  
Author(s):  
Rongcai Yuan ◽  
Duane W. Greene
Keyword(s):  
Growth Rate ◽  
Apple Fruit ◽  
Fruit Weight ◽  
Shoot Tips ◽  
Fruit Growth ◽  
Shoot Tip ◽  
Soluble Solids ◽  
Leaf Number ◽  
Solids Concentration ◽  
Fruiting Branch

Experiments were conducted to evaluate the effects of BA, removal of bourse shoot tips including only folded leaves and growing point, and different numbers of leaves per fruit on fruit retention and fruit development in `More-Spur McIntosh'/Malling 7 (M.7) apple trees [Malus sylvestris (L.) Mill var. domestica (Borkh.) Mansf.]. Removal of the bourse shoot tip increased fruit retention, whereas BA thinned fruit regardless of whether shoot tips were removed or not. There was no interaction between BA application and shoot tipping. BA thinned fruit only when one leaf per fruit was on a girdled small fruiting branch, but not when leaf number per fruit was two or greater. Fruit weight and soluble solids concentration increased dramatically with increasing leaf number per fruit. BA reduced fruit growth rate when <16 leaves per fruit were present on the girdled branches between 3 and 7 days after treatment, but it did not affect fruit growth rate when 32 leaves per fruit were on the girdled branches. Increasing leaf number also increased viable seed number per fruit while decreasing the number of aborted seeds, but it had no effect on the number of total seeds per fruit. BA reduced the number of viable seeds per fruit only when the number of leaves per fruit was less than four. Results suggest that BA thins apple fruit mainly by reducing carbohydrates available to developing fruitlets. Chemical name used: N-(phenylmethyl)-1H-purine-6-amine [benzyladenine (BA)].

scholarly journals Light Environment and Time of Harvest Affect `Delicious' Apple Fruit Quality Characteristics

1992 ◽  
Vol 117 (4) ◽  
pp. 551-557 ◽  
Author(s):  
Richard J. Campbell ◽  
Richard P. Marini
Keyword(s):  
Photosynthetic Photon Flux Density ◽  
Apple Fruit ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Photon Density ◽  
Fruit Characteristics ◽  
Solids Concentration ◽  
Harvest Dates

Photosynthetic photon flux density (PPFD), measured at various canopy positions throughout the growing season in 1989 and 1990, was used to explain variation in fruit characteristics of `Delicious' apples (Malus domestica Borkh.) harvested from these positions at 135, 145, 155, and 165 days after full bloom (DAFB). Hours above an average PPFD threshold of 250 μmol·m-2·s-1 (HR250) explained an average of only 2% more variation in fruit characteristics than other PPFD threshold levels or total cumulative photosynthetic photon density (PPD) in each year. Percent of red surface had a positive linear relationship with HR250 on all harvest dates in both years; intercepts increased on each successive harvest. The slopes and R2 were highest at 135 DAFB and decreased on each successive harvest. Intensity of red pigmentation and soluble solids concentration also increased linearly with HR250, with equivalent slopes and increasing intercepts on each successive harvest. Fruit weight, flesh firmness, length: diameter ratio, and starch index were not consistently affected by any measure of canopy light levels. Except for intensity of redness, relationships developed between fruit characteristics and cumulative late-season PPD during the final 10 weeks before harvest (CPPDLS) had trends similar to the models for HR250 for all harvests in both years. Models developed with instantaneous light measurements were similar to those developed with the more detailed cumulative light measurements.

scholarly journals Apple Fruit Growth and Maturity are Affected by Early Season Temperatures

1999 ◽  
Vol 124 (5) ◽  
pp. 468-477 ◽  
Author(s):  
I.J. Warrington ◽  
T.A. Fulton ◽  
E.A. Halligan ◽  
H.N. de Silva
Keyword(s):  
Fruit Size ◽  
Temperature Treatment ◽  
Apple Fruit ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Cool Temperature ◽  
Fruit Maturation ◽  
Solids Concentration ◽  
Golden Delicious ◽  
General Response

Container-grown `Delicious', `Golden Delicious', `Braeburn', `Fuji' and `Royal Gala' apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] trees, on Malling 9 (M.9) rootstock, were subjected to a range of different maximum/minimum air temperature regimes for up to 80 days after full bloom (DAFB) in controlled environments to investigate the effects of temperature on fruit expansion, final fruit weight, and fruit maturation. Fruit expansion rates were highly responsive to temperature with those at a mean of 20 °C being ≈10 times greater than those at a mean of 6 °C. All cultivars exhibited the same general response although `Braeburn' consistently showed higher expansion rates at all temperatures compared with lowest rates for `Golden Delicious' and intermediate rates for both `Delicious' and `Fuji'. The duration of cell division, assessed indirectly by measuring expansion rate, appeared to be inversely related to mean temperature (i.e., prolonged under cooler conditions). Subsequently, fruit on trees from the coolest controlled temperature treatment showed greater expansion rates when transferred to the field and smaller differences in fruit size at harvest than would have been expected from the measured expansion rates under the cool treatment. Nonetheless, mean fruit weight from warm postbloom treatments was up to four times greater at harvest maturity than that from cool temperature treatments. Postbloom temperature also markedly affected fruit maturation. Fruit from warm postbloom temperature conditions had a higher soluble solids concentration, more yellow background color, lower flesh firmness, and greater starch hydrolysis than fruit from cooler temperatures.

Experiments on the Mechanical Harvesting of Litchi and its Effects on Litchi Storage

2017 ◽  
Vol 60 (5) ◽  
pp. 1529-1535 ◽  
Author(s):  
Weizu Wang ◽  
Huazhong Lu ◽  
Changki Mo ◽  
Zhou Yang ◽  
Cameron Jay Hohimer ◽  
...  
Keyword(s):  
Chemical Treatment ◽  
Field Testing ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Guangzhou City ◽  
Detachment Force ◽  
Damage Rate ◽  
Fruiting Branch ◽  
Solids Content ◽  
Different Characteristics

Abstract. This article presents a fruiting branch shaker designed for litchi ( Sonn.) harvesting and field testing results of the mechanical shaker with abscission chemical treatment. During the mature litchi season, mechanical harvesting experiments were conducted on Feizixiao litchi trees with and without applying the abscission chemical (Ethrel, 2-chloroethyl phosphoric acid). Fruit detachment force (FDF) and fruit weight (W) were measured to determine the effect of chemical treatment on the FDF/W ratio. Fruits harvested by different methods were transported to the laboratory in Guangzhou city and stored at 6°C. Testing results showed that more than 88% of litchi fruits untreated with the chemical were removed at a frequency of 26 or 32 Hz and that the harvesting rate was roughly 3.5 times greater than that of hand harvesting. Application of the abscission chemical increased the removal percentage and harvesting rate of litchi fruits by about 10% while showing a decreased damage rate. Storage tests also indicated no significantly different characteristics between untreated fruits harvested by the shaker and by hand. However, there were significant differences between treated fruits and untreated fruit in browning index and total soluble solids content. Keywords: Abscission chemical, Detachment force, Litchi (Litchi chinensis Sonn.), Mechanical harvest, Multi-finger branch shaking.

scholarly journals Effect of Shading on Red Colour and Fruit Quality in Blush Pears “ANP-0118” and “ANP-0131”

Plants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 206 ◽  
Author(s):  
Madeleine Peavey ◽  
Ian Goodwin ◽  
Lexie McClymont ◽  
Subhash Chandra
Keyword(s):  
Visual Assessment ◽  
Quality Parameters ◽  
Fruit Weight ◽  
Soluble Solids ◽  
A Value ◽  
Solids Concentration ◽  
Negative Effect ◽  
Colour Parameters ◽  
Hue Angle ◽  
Colour Development

Some cultivars of Pyrus communis develop mature fruit with a distinctive red blush. Investigating the patterns of pear colour development in response to sunlight has implications for orchard management of these pears. The objectives of these experiments are to study the seasonal patterns of colour development and investigate the influence of shade and sunlight exposure on the red colour and harvest quality of blush pears “ANP-0118” and “ANP-0131”. Several long, medium and short shading treatments were applied at different stages of fruit development from 28 (“ANP-0131”) and 29 (“ANP-0118”) days after full bloom (DAFB) until harvests at 119 DAFB (“ANP-0118”) and 175 DAFB (“ANP-0131”). Fruits were measured every three weeks for colour parameters (a*, hue angle, chroma) and at harvest for quality parameters (fresh weight, visual assessments of percentage blush coverage and blush intensity, flesh firmness and soluble solids concentration). In the unshaded control, red colour increased during the growing season (increase in a* value and decrease in hue angle), as well as increasing in chroma value. Periods of shading during the season negatively affected red colour in both cultivars, as evidenced by significant decreases in a* value and increases in hue angle. Shaded fruits that were subsequently re-exposed to sunlight reacted with a dynamic increase in a* value and decrease in hue angle. Fruit shaded for the length of the experiment or prior to harvest had significantly lower a* values than the control at harvest. Visual assessment at harvest of percentage blush coverage and blush intensity were significantly affected by shading in both cultivars. Shading treatments applied early in the experiment had a negative effect on the fresh fruit weight of “ANP-0118”.

scholarly journals AN EVALUATION OF BENZYLADENINE AS A POSSIBLE CHEMICAL THINNER OF “EMPIRE”

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 592a-592
Author(s):  
V.E. Emongor ◽  
D.P. Murr ◽  
J.T.A Proctor ◽  
E.C. Lougheed
Keyword(s):  
Field Trials ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Research Station ◽  
Full Bloom ◽  
Ethylene Concentration ◽  
Solids Concentration ◽  
Cambridge Research ◽  
Thinning Effect ◽  
Soluble Solids Concentration

Field trials at Cambridge Research Station, Ontario, Canada, studied the thinning effect of benzyladenine (BA) on eighteen-year-old “Empire” apple trees. At 16 days after full bloom (fruit diameter 12.87 mm) whole trees were hand sprayed to drip point with BA (0, 100, or 200 mg.1-1). Untreated control trees were compared with treated and hand thinned trees. BA significantly reduced crop load on “Empire”. The thinning response to BA was linear, with recommended thinning occurring at 200 mg.1-1. At harvest, fruit weight, size (diameter and length), flesh firmness and soluble solids concentration, chlorophyll and anthocyanin contents, and seed number were increased by BA treatments. BA had no effect on fruit L:D ratio, internal ethylene concentration, maturity, and the onset of the respiratory climacteric, but significantly reduced respiration at harvest. BA also reduced ethylene production and ACC content at harvest, though the reduction was not significant. Although firmness of BA-treated fruit was significantly higher at harvest, upon storage for 1 month at 0-0.5°C and 90-95% RH the firmness advantage was lost BA shows potential as a thinner of “Empire” apple and has advantage of increasing fruit weight and size, since “Empire” is a relatively small apple compared to other commercial cultivars.

scholarly journals FRUIT GROWTH AND DESWEETING AMONG LONGAN (Euphoria longana Lam.) VARIETIES

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 669h-670
Author(s):  
Chung-Ruey Yen ◽  
Jer-Way Chang
Keyword(s):  
Fruit Development ◽  
Growth Curves ◽  
Fruit Weight ◽  
Fruit Growth ◽  
Soluble Solids ◽  
Water Inflow ◽  
Total Soluble Solids ◽  
Full Development ◽  
Water Contents

Fruit growth curves of three longan varieties showed single sigmoid. Seed was the major sink in longan at early fruit development. Aril grew only after seed had approached full development. Early `Yangtaoyeh' grew more rapidly than two later varieties. Desweeting, levels of aril total soluble solids (TSS) increased to maximum and then declined gradually at later fruit development, occurs often in longan. Variation of desweeting rate among varieties was significant. Increases of fruit weight during desweeting (from dates of maximum TSS to end of experiment) were 55.4%, 50.9%, and 7.3% for `Yangtaoyeh', `Fenko', and `Shihyueh', respectively. Periods of water contents increase in aril coincided with the changes of fruit weight of three varieties. Dilution of TSS by water inflow was one of major factor of desweeting in longan fruit. Girdling did not slow down decline of aril total soluble solids.

scholarly journals Postharvest Sensory and Physicochemical Attributes of Honey Dew Melon Fruits

HortScience ◽  
1992 ◽  
Vol 27 (9) ◽  
pp. 1012-1014 ◽  
Author(s):  
Gene Lester ◽  
Krista C. Shellie
Keyword(s):  
Fruit Shape ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Epidermal Tissue ◽  
Solids Concentration ◽  
Fruit Preference ◽  
L Value ◽  
Fruit Flavor ◽  
Soluble Solids Concentration ◽  
Physicochemical Measurements

Physicochemical and sensory attributes of fully mature honey dew melon (Cucumis melo L. var. inodorus Naud.) fruits were evaluated 10 days after storage for eight commercial cultivars grown in two locations. Cultivars varied in degree of pref- erence expressed by panelists' ratings for overall fruit preference, flavor, and shape and for physicochemical measurements of soluble solids concentration (SSC), flesh firmness, and fruit weight. The sensory attribute that correlated most strongly with overall fruit preference was fruit flavor (r = 0.97). The whiteness of epidermal tissue (rind L value) and SSC correlated more highly with overall fruit preference (r = 0.54 and r = 0.52, respectively) than other physicochemical attributes, such as fruit firm- ness (r = -0.24) and fruit weight (r = -0.12). Epidermal L value correlated more strongly with panelists' ratings for fruit shape (r = 0.69) than with fruit flavor (r = 0.35), but SSC correlated more strongly with fruit flavor (r = 0.61) than with fruit shape (r = 0.30). Superior honey dew melon quality at harvest was associated with high SSC, white epidermal tissue, and round fruit shape.

scholarly journals Morphological and Physiological Changes during Fruit Growth and Maturation of Seven Melon Cultivars

1991 ◽  
Vol 116 (6) ◽  
pp. 1025-1029 ◽  
Author(s):  
Vito Miccolis ◽  
Mikal E. Saltveit
Keyword(s):  
Cucumis Melo ◽  
Fruit Size ◽  
Marked Change ◽  
Fruit Growth ◽  
Soluble Solids ◽  
Flesh Color ◽  
Santa Claus ◽  
Solids Concentration ◽  
General Decline ◽  
Soluble Solids Concentration

External color, length, diameter, fresh weight, C02 production, internal C2HA concentration, flesh firmness, soluble solids concentration (SSC), flesh color, and seed cavity diameter were measured during fruit growth and maturation of seven melon cultivars (Cucumis melo L., Inodorus Group, Naud. cv. `Amarelo', `Golden Beauty Casaba', `Honey Dew', `Honey Loupe', `Juan Canary', `Paceco', and `Santa Claus Casaba') of known age. There was no increase in C02 production either during ripening (e.g., loss of firmness and increased SSC) or with increasing C2H4 levels in fruit from any of the seven cultivars. There was a significant decline in respiration only at the second sampling date, which ranged from 14 to 18 days after anthesis. Respiration measured 1 week later was substantially higher and was followed by a general decline. This post 14- to 18-day rise in respiration was not a climacteric since it occurred well in advance of other ripening characteristics, e.g., loss of firmness, increase in SSC, or rise in internal C2H4. The increase in internal C2H4. coincided with or followed attainment of full fruit size, while flesh softening and the rapid rise in SSC preceded the rise in internal C2H4, concentration. Respiration declined from 67 to 18 ml CO2/kg per hour by day 43 in all cultivars, except `Honey Dew' and `Honey Loupe'. Respiration in `Honey Loupe' remained above 23 ml CO2/kg per hour and showed a rise to 32 ml/kg per hour on day 53. Respiration in `Honey Dew' did not fall below 18 ml CO2/kg per hour until day 53. As with internal C2H4 levels, there was no correlation between changes in and any marked change in the other signs of ripening that were measured.

scholarly journals Preharvest Aminoethoxyvinylglycine Plus Postharvest Heat Treatments Influence Apple Fruit Ripening after Cold Storage

HortScience ◽  
2009 ◽  
Vol 44 (6) ◽  
pp. 1637-1640 ◽  
Author(s):  
Valeria Sigal Escalada ◽  
Douglas D. Archbold
Keyword(s):  
Cold Storage ◽  
Ethylene Production ◽  
Combined Treatment ◽  
Titratable Acidity ◽  
Apple Fruit ◽  
Soluble Solids ◽  
Limiting Factor ◽  
Acyltransferase Activity ◽  
Solids Concentration ◽  
The Impact

The impact of heat plus aminoethoxyvinylglycine (AVG) treatments alone or in combination on ripening of four apple cultivars has been studied. A solution of AVG was applied to ‘Lodi’, ‘Senshu’, ‘Redchief Delicious’, and ‘Red Fuji’ apple trees ≈4 weeks before normal harvest at 124 g·ha−1 a.i. After harvest, half of each group of control and AVG-treated fruit was heated at 38 °C for 4 days and then stored at 4 °C for 30 days. After cold storage, AVG and heat individually suppressed ethylene production of ‘Senshu’ and ‘Redchief Delicious’ but not of ‘Lodi’ or ‘Red Fuji’. The combination of AVG with heat treatment reduced ethylene production the most consistently in each cultivar except ‘Lodi’, suggesting some additive effect of the treatments. The respiration rate after cold storage was not consistently affected by any treatment. AVG alone and with heat maintained firmness of ‘Lodi’, AVG plus heat maintained it in ‘Senshu’, but neither ‘Redchief Delicious’ nor ‘Red Fuji’ firmness responded to the treatments. AVG-treated ‘Lodi’ and ’Redchief Delicious’ fruit, heated fruit of all cultivars, and AVG plus heat in all had lower titratable acidity than controls after cold storage. Although there were no effects of any treatment on fruit soluble solids concentration, the combined treatment increased the soluble solids:titratable acidity ratio of all cultivars, although heat or AVG alone had no consistent effects. Total ester production by ‘Redchief Delicious’ peel tissue after cold storage was reduced 44% by AVG and 70% or more by heat and AVG plus heat. There were no differences in peel alcohol acyltransferase activity among the treatments, supporting the hypothesis that substrate availability was the limiting factor for ester synthesis in treated fruit. Overall, heat plus AVG treatment did not provide any advantage over each alone for maintaining apple fruit quality during short-term cold storage.

scholarly journals AVG Effects on Preharvest Apple Fruit Drop and Maturity in Virginia

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 694f-695
Author(s):  
Ross E. Byers
Keyword(s):  
Apple Fruit ◽  
Harvest Date ◽  
Soluble Solids ◽  
Fruit Firmness ◽  
Color Development ◽  
Fruit Drop ◽  
Solids Concentration ◽  
Red Color ◽  
Golden Delicious ◽  
Standard Rate

AVG applied 2 to 6 weeks before the optimum harvest date for several cultivars dramatically reduced pre-harvest fruit drop. The loss of fruit firmness and starch loss after the optimum harvest date was reduced by AVG sprays. The development of watercore in `Starkrimson Delicious' and `York' and maturity cracking in `Rome' and `Golden Delicious' were delayed and/or prevented by AVG. Color development was slightly delayed for most red cultivars and `Golden Delicious'. Soluble solids concentration was generally unchanged. Airblast applications of 123 g·ha–1 AVG was no more effective than a standard rate of NAA (28 to 56 g·ha–1), but rates of 248 g·ha–1 AVG and above were more effective than NAA for most cultivars. When fruit were left on the tree for periods of 3 to 5 weeks after the optimum harvest date, NAA hastened the loss of fruit firmness and starch and NAA increased watercore of `Delicious' and maturity cracking of `Golden Delicious' and `Law Rome'. Soluble solids and red color were generally unaffected by NAA. Ethephon sprays hastened the rate of fruit drop. When NAA was tank mixed with ethephon, NAA delayed fruit drop caused by ethephon, but AVG did not. The use of superior oil or Regulaid surfactant did not affect NAA or AVG responses; however, the silicone surfactant Silwet L-77, in one experiment, promoted the effectiveness of AVG. Tank mixing NAA or AVG with pesticides (Guthion + Lannate + Captan) did not affect the responses of AVG or NAA on fruit drop.

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