Renae Moran - Academia.edu (original) (raw)

Papers by Renae Moran

HortScience

The goal of this research was to evaluate resistance of apple rootstocks to late winter deacclima... more The goal of this research was to evaluate resistance of apple rootstocks to late winter deacclimation during a 2-day exposure to warm temperatures in Maine. We measured the cold temperature tolerance of xylem, phloem, and cambium from 0 to −40 °C in 1- and 2-year-old shoot pieces from apple rootstock cultivars and advanced selections ‘M.9 T337’ (M.9), ‘M.7 EMLA’ (M.7), ‘Budagovsky 9’ (B.9), ‘Geneva® 41’ (G.41), ‘Geneva 30’ (G.30), ‘Geneva 935’ (G.935), ‘Geneva 814’ (G.814), G.4013, G.5257, and Vineland 6 (V.6) after a 2-day exposure to warm (22 °C) or cold (2 to 4 °C) temperatures. Injury was measured on a 0 to 10 rating scale based on percentage of discolored cross-sectional xylem and phloem, and cambial length and circumference with brown discoloration, with 0 indicating no browning and 10 indicating browning in the entire tissue. Injury was also measured as intensity of browning on a scale of 0 (no browning) to 5 (dark brown to black). The weighted averages of the two ratings wer...

HortScience

We evaluated regional variation in the Delta Absorbance Meter® index of absorbance difference (IA... more We evaluated regional variation in the Delta Absorbance Meter® index of absorbance difference (IAD) as a measure of harvest maturity and for predicting the occurrence of storage disorders in ‘McIntosh’ apples [Malus ×sylvestris (L.) var. domestica (Borkh.) Mansf.] in 2016 and ‘Honeycrisp’ apples in 2016 and 2017. Apples were grown in Maine (ME), Minnesota (MN), and Ontario (ON), and they were harvested from one orchard in each region, and two to three times each year, followed by cold storage at 0.5 °C for 2 months in 2016 and 4 months in 2017. In 2016, ‘Honeycrisp’ IAD values were similar in ME and ON, but lower than in MN. In 2017, IAD was greater in ME than in the other two regions during the first harvest, and it similar to MN in the latter two harvests and lower in ON than in the other regions. In ‘Honeycrisp’ apples, IAD was more strongly related to starch pattern index (SPI), internal ethylene concentration, and fruit peel blush than to chlorophyll or soluble solids concentra...


HortScience

'Honeycrisp' is a new apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] cultivar... more 'Honeycrisp' is a new apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] cultivar that has been planted extensively in North America, but the storage disorders soggy breakdown and soft scald have resulted in major fruit losses. The effects of harvest date and storage temperature on fruit quality and susceptibility of fruit to these disorders have been investigated in Michigan, New York, and Maine. Internal ethylene concentrations were variable over a wide range of harvest dates, and a rapid increase in autocatalytic ethylene production was not always apparent. The starch pattern index, soluble solids content, titratable acidity and firmness also appear to have limited use as harvest indices. Development of soggy breakdown and soft scald is associated with later harvest dates and storage of fruit at temperatures of 0 to 0.5 °C compared with higher storage temperatures. It is recommended that 'Honeycrisp' be stored at 3 °C, although storage disorders still can occur at this temperature if fruit are harvested late. In addition, greasiness development may be worse at higher storage temperatures.

HortScience

Trunk cross-sectional area (TCA) has been used to estimate leaf area (LA) and yield efficiency bu... more Trunk cross-sectional area (TCA) has been used to estimate leaf area (LA) and yield efficiency but variation in LA and TCA relationships have been unexplored. LA and TCA of 10-yr-old 'Starkspur Supreme Delicious' on 9 rootstocks (STKs) were measured in 1989. LA and TCA of 2-yr-old trees of 3 cultivars (CVs) on 5 STKs were measured in 1991. Regression of LA and TCA was performed for each CV, STK and each CV/STK. On mature trees, LA varied significantly with STK. The number and LA of shoot leaves (LVS) and spur LVS varied with STK but the % of total was not significantly different (approx. 52% spur LVS). The relationships of LA and TCA were linear for mature (r2=.94) and young (r2=.44) trees. On young trees, TCA varied with CV, but LA did not. Both LA and TCA were significantly different among STKs. The linear relationships of LA and TCA had unique intercepts with each CV, STK and CV/STK combination but slopes were not significantly different. Leaf area of Jonagold' and &#...

HortScience

Greenhouse grown `Lawspur Rome'/M.111 trained to single shoots were given the following shade... more Greenhouse grown `Lawspur Rome'/M.111 trained to single shoots were given the following shade (73%) treatments: 1) sun-all-day (control), 2) shade in the morning (am-shade), 3) shade in the afternoon (pm-shade) and 4) shade-all-day. All shade treatments increased shoot length and decreased dry weight/leaf area (DW/LA). Shade-all-day increased leaf no., LA/leaf and shoot dia. DW partitioning to leaves in shade-all-day was 19% greater than control and to roots was 34% less than control. Pn of am-shade did not increase in the afternoon when PFD was maximal. Saturated net photosynthesis (Pn) was 72% of control in am-shade, 84% of control in pm-shade and 62% in shade-all-day. Shade reduced Pn by 40% of control.

HortScience

Dormant applications of 0% to 20% soybean oil were tested as a prebloom thinner of `Georgia Belle... more Dormant applications of 0% to 20% soybean oil were tested as a prebloom thinner of `Georgia Belle' and `Redhaven' peach flower buds. Five separate experiments were conducted with soybean oil applied in late Jan. or early Feb. 1992, 1993, 1995, and 1997. The number of living and dead flower buds was counted on five or 10 shoots per tree before and 1 month after application in Expts. 1, 2, 3, and 4. In Expt. 5, buds were counted on two to three shoots per tree before and after a freeze of –4 °C during petal fall. Soybean oil thinned flower buds in all five experiments. The amount of flower bud death was concentration dependent with maximum bud kill of 53% occurring with application of 12% oil. Thinning was fairly consistent from year to year, ranging from 34% to 51% when 10% oil was applied, but was less uniform when 5% oil was applied and ranged from 6% to 40%. Overthinning occurred in Expt. 3 by all oil concentrations tested. Bud death in untreated trees was 40% in this expe...

HortScience

Additional index words. Malus ×domestica, fl owering, vegetative growth, soil amendments Abstract... more Additional index words. Malus ×domestica, fl owering, vegetative growth, soil amendments Abstract. 'Macounʼ/Budagovsky 9 apple (Malus ×domestica Borkh.) trees were planted in May 1998 in one of four preplant treat ments that were soil incorporation of: 1) control, no phos pho rus (P); 2) 90 g P per tree; 3) 128 kg compost per tree; and 4) 90 g P and 128 kg compost per tree. Preplant addition of P had no effect on soil organic matter, P, magnesium (Mg), and calcium (Ca) in the fi rst three sea sons after planting, but lowered soil potassium (K) in the sec ond season. Foliar nutrients, tree growth and fl owering were also not affected by P. The addition of compost increased soil or gan ic matter and P in the fi rst season after planting, and pH, K, Mg, and Ca in the fi rst three seasons. The addition of compost in creased foliar nitrogen and K in all three seasons, and decreased foliar Mg in the fi rst season. Compost incorporation in creased shoot length in the fi rst season, trunk cross-sectional area in the fi rst two seasons, tree height and the number of grow ing points in third season, and fl owering in the third and fourth seasons. Compost ad di tion was more effective than P fer til i za tion for increasing tree growth during the es tab lish ment years.

HortScience

Soybean [Glycine max (L.) Merrill] oil was applied to apple trees [Malus sylvestris (L.) Mill var... more Soybean [Glycine max (L.) Merrill] oil was applied to apple trees [Malus sylvestris (L.) Mill var. domestica (Borkh.) Mansf.] as a summer spray in six studies to determine if it controls European red mites [Panonychus ulmi (Koch.)], how it affects net CO2 assimilation (A), and if it causes phytotoxicity. Sprays of 0.5%, 1.0%, and 1.5% soybean oil {TNsoy1 formulation [soybean oil premixed with Latron B-1956 (LAT) spreader-sticker at 10 oil: 1 LAT (v/v)]} reduced mite populations by 94%. Sprays of 1% and 2% soybean oil reduced mite populations to three and four mites per leaf, respectively, compared to 25 per leaf on water-sprayed plants. Soybean oil concentrations of 1.0% and 1.5% applied to whole trees reduced A for less than 7 days. Phytotoxicity did not occur when soybean oil was applied with an airblast sprayer at concentrations of 1.0% and 1.5% or with a mist bottle at 2%. Phytotoxicity occurred when soybean oil was applied with a mist bottle at 4% and 6%, which left soybean oil...


HortScience

Secondary bloom provides fireblight infection sites in pears (Pyrus communis L.) growing in the w... more Secondary bloom provides fireblight infection sites in pears (Pyrus communis L.) growing in the western U.S. Five types of secondary bloom occur in `Bartlett', and one of these, Type V, occurs mainly as a result of pruning. We examined the effect of pruning dates (Feb. to Sept. 1999), shoot age ranging from 1 to 4 years old, and type of pruning cut (i.e., heading, stubbing, or thinning) on Type V secondary bloom. Pruning date was a significant factor determining whether Type V would occur. There was a greater chance for Type V to occur from pruning in February or March than for pruning from May through September. There was an increase in Type V with increase in shoot age when pruning 11 Feb., 17 Mar., 14 May, or 11 Aug. There was no shoot age effect when pruning 18 June or 30 Sept. Type of pruning cut affected the number of Type V that occurred when pruning 14 May, 18 June, or 11 Aug., but the effect of type of pruning cut was inconsistent between these dates. There was no effec...

HortScience

Preconditioning, holding fruit at 10, 17.5, or 21 °C temperatures for up to 7 days before placeme... more Preconditioning, holding fruit at 10, 17.5, or 21 °C temperatures for up to 7 days before placement in cold storage, was inconsistent in its effect on soft scald and soggy breakdown in ‘Honeycrisp’ apples in Maine and Ontario. In Ontario, 4 days of preconditioning at 21 °C increased soft scald in 1 year but had no effect in the next year. Five d of preconditioning at 10 °C reduced soft scald and had no effect on soggy breakdown in 1 year but reduced it the next year. In Maine, 5 days preconditioning at 17.5 °C was effective in reducing soft scald and/or soggy breakdown in 2002 to 2007 when starch index at harvest was 5.9 to 7.2. Seven days of preconditioning at 17.5 °C increased soggy breakdown with an early harvest in two orchards but only in one of two orchards with a later harvest. This same preconditioning had no effect on soft scald with the first harvest but reduced it with the second. In the next year, the same preconditioning treatment increased soft scald and soggy breakdow...

HortScience

'Macoun'/B.9 apple (Malus ×domestica Borkh.) trees were planted in May 1998 in ± compost or ± mon... more 'Macoun'/B.9 apple (Malus ×domestica Borkh.) trees were planted in May 1998 in ± compost or ± monoammonium phosphate (MAP) for a total of four preplant treatments: 1) 90 g phosphorus (P) per tree, 2) 128 kg compost per tree, 3) 90 g P and 128 kg compost per tree, and 4) and an untreated control. MAP did not increase tree growth or yield in any year of the study. Compost increased canopy width into the sixth year after planting, and increased tree height and trunk cross-sectional area (TCA) into the seventh year. Annual yield was increased by compost in the fi fth and seventh years, but not fourth or sixth year after planting. Compost increased cumulative yield in the sixth and seventh years.


HortScience

In 2004, prestorage delays and CA storage were compared for occurrence of disorders. Fruit were h... more In 2004, prestorage delays and CA storage were compared for occurrence of disorders. Fruit were harvested at a starch index of 5.9. Fruit were exposed to either a 2- or 5-day prestorage delay at 17 °C; or placed immediately into cold storage (control) at 0.5 °C. An additional treatment was CA storage at 2.5 °C. In February, occurrence of soft scald, soggy breakdown, and bitter pit were measured on 40 fruit per replication. Fruit were from `Honeycrisp'/M.26 trees planted in 1994. Treatments were replicated five times with four trees in each replication. Soft scald was very severe in this year, with 84% of control fruit being affected. Two-day prestorage delay reduced it to 48% and 5-day delay to 21%. Soggy breakdown was also severe with 14% of the fruit being affected. Two- and 5-day delays had no effect on occurrence of soggy breakdown, but CA storage increased it to 65%. Bitter pit was very rare and not affected by any of the treatments. These results demonstrate that in severe...


HortScience

Preplant soil-incorporated compost, mycorrhyzal innoculation (MI) at planting, and the combinatio... more Preplant soil-incorporated compost, mycorrhyzal innoculation (MI) at planting, and the combination of the two were tested for growth and yield increase of `Honeycrisp' apple trees on two rootstocks, M.26 and G.16. Compost was added at a rate of 0.51 m3 per tree. Within each main plot of compost or no compost were planted four trees with two on each rootstock. Noncompost plots were fertilized with N in year 1 and N, K, and Mg in year 4. The MI had no effect on growth until the third and fourth years after planting when annual trunk growth and tree height were greater than the untreated control. Compost increased trunk growth in the third and fourth years, but decreased growth in the fourth year when combined with MI. G.16 had greater trunk growth and tree height than M.26 in years 3 and 4. Fruiting was delayed by pruning at planting, so trees fruited for the first time in the fourth year. Bloom and yield were not increased by MI. There was more bloom and yield on G.16 than on M.2...

HortScience

The influence of red and blue light wavelengths was tested to improve the initial in vitro multip... more The influence of red and blue light wavelengths was tested to improve the initial in vitro multiplication of apple (Malus × domestica) rootstock cultivars Budagovsky 9 (B.9), Geneva 30 (G.30), and Geneva 41 (G.41). Single-node segments were established in semisolid Murashige and Skoog media and then transferred to proliferation media and cultured 40 days under white, red, or blue light irradiance. In a second experiment, G.30 was cultured under red, blue, or white light with and without gibberellic acid (GA3). The three rootstocks responded similarly under white light in terms of shoot number, length of the longest shoot, and the number of elongated shoots. Red light increased the number of shoots, length of the longest shoot, and the number of elongated shoots of B.9 and G.30 when compared with white or blue light. Red light increased the number of elongated B.9 and G.30 shoots to five per explant compared with one per explant under white light. In contrast, shoot growth of G.41 sh...

Journal of the American Society for Horticultural Science

Soft scald is an apple (Malus ×domestica Borkh.) fruit disorder that appears in response to cold ... more Soft scald is an apple (Malus ×domestica Borkh.) fruit disorder that appears in response to cold storage after about 2–8 weeks. It appears as a ribbon of dark tissue on the peel of the fruit, with occasional browning into the flesh. Several apple cultivars are susceptible to it, including Honeycrisp. The objectives of this study were to examine the cellular microstructure of fruit exhibiting soft scald and determine if any aspect of the peel microstructure at harvest could be indicative of future soft scald incidence. Light and electron microscopy were used to examine the peel microstructure of ‘Honeycrisp’ fruit that were unaffected or affected by soft scald. Tissue with soft scald had brown pigmented epidermal and hypodermal cells, whereas unaffected fruit peel epidermal cells were unpigmented. Cuticular wax of unaffected peel had upright wax platelets or clumps of wax, but peel surfaces with soft scald exhibited flattened granules and were more fragile than that of unaffected fru...

The Journal of Horticultural Science and Biotechnology, 2000

II International Organic Fruit Symposium, 2013

II International Organic Fruit Symposium, 2013

HortScience

The goal of this research was to evaluate resistance of apple rootstocks to late winter deacclima... more The goal of this research was to evaluate resistance of apple rootstocks to late winter deacclimation during a 2-day exposure to warm temperatures in Maine. We measured the cold temperature tolerance of xylem, phloem, and cambium from 0 to −40 °C in 1- and 2-year-old shoot pieces from apple rootstock cultivars and advanced selections ‘M.9 T337’ (M.9), ‘M.7 EMLA’ (M.7), ‘Budagovsky 9’ (B.9), ‘Geneva® 41’ (G.41), ‘Geneva 30’ (G.30), ‘Geneva 935’ (G.935), ‘Geneva 814’ (G.814), G.4013, G.5257, and Vineland 6 (V.6) after a 2-day exposure to warm (22 °C) or cold (2 to 4 °C) temperatures. Injury was measured on a 0 to 10 rating scale based on percentage of discolored cross-sectional xylem and phloem, and cambial length and circumference with brown discoloration, with 0 indicating no browning and 10 indicating browning in the entire tissue. Injury was also measured as intensity of browning on a scale of 0 (no browning) to 5 (dark brown to black). The weighted averages of the two ratings wer...

HortScience

We evaluated regional variation in the Delta Absorbance Meter® index of absorbance difference (IA... more We evaluated regional variation in the Delta Absorbance Meter® index of absorbance difference (IAD) as a measure of harvest maturity and for predicting the occurrence of storage disorders in ‘McIntosh’ apples [Malus ×sylvestris (L.) var. domestica (Borkh.) Mansf.] in 2016 and ‘Honeycrisp’ apples in 2016 and 2017. Apples were grown in Maine (ME), Minnesota (MN), and Ontario (ON), and they were harvested from one orchard in each region, and two to three times each year, followed by cold storage at 0.5 °C for 2 months in 2016 and 4 months in 2017. In 2016, ‘Honeycrisp’ IAD values were similar in ME and ON, but lower than in MN. In 2017, IAD was greater in ME than in the other two regions during the first harvest, and it similar to MN in the latter two harvests and lower in ON than in the other regions. In ‘Honeycrisp’ apples, IAD was more strongly related to starch pattern index (SPI), internal ethylene concentration, and fruit peel blush than to chlorophyll or soluble solids concentra...


HortScience

'Honeycrisp' is a new apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] cultivar... more 'Honeycrisp' is a new apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] cultivar that has been planted extensively in North America, but the storage disorders soggy breakdown and soft scald have resulted in major fruit losses. The effects of harvest date and storage temperature on fruit quality and susceptibility of fruit to these disorders have been investigated in Michigan, New York, and Maine. Internal ethylene concentrations were variable over a wide range of harvest dates, and a rapid increase in autocatalytic ethylene production was not always apparent. The starch pattern index, soluble solids content, titratable acidity and firmness also appear to have limited use as harvest indices. Development of soggy breakdown and soft scald is associated with later harvest dates and storage of fruit at temperatures of 0 to 0.5 °C compared with higher storage temperatures. It is recommended that 'Honeycrisp' be stored at 3 °C, although storage disorders still can occur at this temperature if fruit are harvested late. In addition, greasiness development may be worse at higher storage temperatures.

HortScience

Trunk cross-sectional area (TCA) has been used to estimate leaf area (LA) and yield efficiency bu... more Trunk cross-sectional area (TCA) has been used to estimate leaf area (LA) and yield efficiency but variation in LA and TCA relationships have been unexplored. LA and TCA of 10-yr-old 'Starkspur Supreme Delicious' on 9 rootstocks (STKs) were measured in 1989. LA and TCA of 2-yr-old trees of 3 cultivars (CVs) on 5 STKs were measured in 1991. Regression of LA and TCA was performed for each CV, STK and each CV/STK. On mature trees, LA varied significantly with STK. The number and LA of shoot leaves (LVS) and spur LVS varied with STK but the % of total was not significantly different (approx. 52% spur LVS). The relationships of LA and TCA were linear for mature (r2=.94) and young (r2=.44) trees. On young trees, TCA varied with CV, but LA did not. Both LA and TCA were significantly different among STKs. The linear relationships of LA and TCA had unique intercepts with each CV, STK and CV/STK combination but slopes were not significantly different. Leaf area of Jonagold' and &#...

HortScience

Greenhouse grown `Lawspur Rome'/M.111 trained to single shoots were given the following shade... more Greenhouse grown `Lawspur Rome'/M.111 trained to single shoots were given the following shade (73%) treatments: 1) sun-all-day (control), 2) shade in the morning (am-shade), 3) shade in the afternoon (pm-shade) and 4) shade-all-day. All shade treatments increased shoot length and decreased dry weight/leaf area (DW/LA). Shade-all-day increased leaf no., LA/leaf and shoot dia. DW partitioning to leaves in shade-all-day was 19% greater than control and to roots was 34% less than control. Pn of am-shade did not increase in the afternoon when PFD was maximal. Saturated net photosynthesis (Pn) was 72% of control in am-shade, 84% of control in pm-shade and 62% in shade-all-day. Shade reduced Pn by 40% of control.

HortScience

Dormant applications of 0% to 20% soybean oil were tested as a prebloom thinner of `Georgia Belle... more Dormant applications of 0% to 20% soybean oil were tested as a prebloom thinner of `Georgia Belle' and `Redhaven' peach flower buds. Five separate experiments were conducted with soybean oil applied in late Jan. or early Feb. 1992, 1993, 1995, and 1997. The number of living and dead flower buds was counted on five or 10 shoots per tree before and 1 month after application in Expts. 1, 2, 3, and 4. In Expt. 5, buds were counted on two to three shoots per tree before and after a freeze of –4 °C during petal fall. Soybean oil thinned flower buds in all five experiments. The amount of flower bud death was concentration dependent with maximum bud kill of 53% occurring with application of 12% oil. Thinning was fairly consistent from year to year, ranging from 34% to 51% when 10% oil was applied, but was less uniform when 5% oil was applied and ranged from 6% to 40%. Overthinning occurred in Expt. 3 by all oil concentrations tested. Bud death in untreated trees was 40% in this expe...

HortScience

Additional index words. Malus ×domestica, fl owering, vegetative growth, soil amendments Abstract... more Additional index words. Malus ×domestica, fl owering, vegetative growth, soil amendments Abstract. 'Macounʼ/Budagovsky 9 apple (Malus ×domestica Borkh.) trees were planted in May 1998 in one of four preplant treat ments that were soil incorporation of: 1) control, no phos pho rus (P); 2) 90 g P per tree; 3) 128 kg compost per tree; and 4) 90 g P and 128 kg compost per tree. Preplant addition of P had no effect on soil organic matter, P, magnesium (Mg), and calcium (Ca) in the fi rst three sea sons after planting, but lowered soil potassium (K) in the sec ond season. Foliar nutrients, tree growth and fl owering were also not affected by P. The addition of compost increased soil or gan ic matter and P in the fi rst season after planting, and pH, K, Mg, and Ca in the fi rst three seasons. The addition of compost in creased foliar nitrogen and K in all three seasons, and decreased foliar Mg in the fi rst season. Compost incorporation in creased shoot length in the fi rst season, trunk cross-sectional area in the fi rst two seasons, tree height and the number of grow ing points in third season, and fl owering in the third and fourth seasons. Compost ad di tion was more effective than P fer til i za tion for increasing tree growth during the es tab lish ment years.

HortScience

Soybean [Glycine max (L.) Merrill] oil was applied to apple trees [Malus sylvestris (L.) Mill var... more Soybean [Glycine max (L.) Merrill] oil was applied to apple trees [Malus sylvestris (L.) Mill var. domestica (Borkh.) Mansf.] as a summer spray in six studies to determine if it controls European red mites [Panonychus ulmi (Koch.)], how it affects net CO2 assimilation (A), and if it causes phytotoxicity. Sprays of 0.5%, 1.0%, and 1.5% soybean oil {TNsoy1 formulation [soybean oil premixed with Latron B-1956 (LAT) spreader-sticker at 10 oil: 1 LAT (v/v)]} reduced mite populations by 94%. Sprays of 1% and 2% soybean oil reduced mite populations to three and four mites per leaf, respectively, compared to 25 per leaf on water-sprayed plants. Soybean oil concentrations of 1.0% and 1.5% applied to whole trees reduced A for less than 7 days. Phytotoxicity did not occur when soybean oil was applied with an airblast sprayer at concentrations of 1.0% and 1.5% or with a mist bottle at 2%. Phytotoxicity occurred when soybean oil was applied with a mist bottle at 4% and 6%, which left soybean oil...


HortScience

Secondary bloom provides fireblight infection sites in pears (Pyrus communis L.) growing in the w... more Secondary bloom provides fireblight infection sites in pears (Pyrus communis L.) growing in the western U.S. Five types of secondary bloom occur in `Bartlett', and one of these, Type V, occurs mainly as a result of pruning. We examined the effect of pruning dates (Feb. to Sept. 1999), shoot age ranging from 1 to 4 years old, and type of pruning cut (i.e., heading, stubbing, or thinning) on Type V secondary bloom. Pruning date was a significant factor determining whether Type V would occur. There was a greater chance for Type V to occur from pruning in February or March than for pruning from May through September. There was an increase in Type V with increase in shoot age when pruning 11 Feb., 17 Mar., 14 May, or 11 Aug. There was no shoot age effect when pruning 18 June or 30 Sept. Type of pruning cut affected the number of Type V that occurred when pruning 14 May, 18 June, or 11 Aug., but the effect of type of pruning cut was inconsistent between these dates. There was no effec...

HortScience

Preconditioning, holding fruit at 10, 17.5, or 21 °C temperatures for up to 7 days before placeme... more Preconditioning, holding fruit at 10, 17.5, or 21 °C temperatures for up to 7 days before placement in cold storage, was inconsistent in its effect on soft scald and soggy breakdown in ‘Honeycrisp’ apples in Maine and Ontario. In Ontario, 4 days of preconditioning at 21 °C increased soft scald in 1 year but had no effect in the next year. Five d of preconditioning at 10 °C reduced soft scald and had no effect on soggy breakdown in 1 year but reduced it the next year. In Maine, 5 days preconditioning at 17.5 °C was effective in reducing soft scald and/or soggy breakdown in 2002 to 2007 when starch index at harvest was 5.9 to 7.2. Seven days of preconditioning at 17.5 °C increased soggy breakdown with an early harvest in two orchards but only in one of two orchards with a later harvest. This same preconditioning had no effect on soft scald with the first harvest but reduced it with the second. In the next year, the same preconditioning treatment increased soft scald and soggy breakdow...

HortScience

'Macoun'/B.9 apple (Malus ×domestica Borkh.) trees were planted in May 1998 in ± compost or ± mon... more 'Macoun'/B.9 apple (Malus ×domestica Borkh.) trees were planted in May 1998 in ± compost or ± monoammonium phosphate (MAP) for a total of four preplant treatments: 1) 90 g phosphorus (P) per tree, 2) 128 kg compost per tree, 3) 90 g P and 128 kg compost per tree, and 4) and an untreated control. MAP did not increase tree growth or yield in any year of the study. Compost increased canopy width into the sixth year after planting, and increased tree height and trunk cross-sectional area (TCA) into the seventh year. Annual yield was increased by compost in the fi fth and seventh years, but not fourth or sixth year after planting. Compost increased cumulative yield in the sixth and seventh years.


HortScience

In 2004, prestorage delays and CA storage were compared for occurrence of disorders. Fruit were h... more In 2004, prestorage delays and CA storage were compared for occurrence of disorders. Fruit were harvested at a starch index of 5.9. Fruit were exposed to either a 2- or 5-day prestorage delay at 17 °C; or placed immediately into cold storage (control) at 0.5 °C. An additional treatment was CA storage at 2.5 °C. In February, occurrence of soft scald, soggy breakdown, and bitter pit were measured on 40 fruit per replication. Fruit were from `Honeycrisp'/M.26 trees planted in 1994. Treatments were replicated five times with four trees in each replication. Soft scald was very severe in this year, with 84% of control fruit being affected. Two-day prestorage delay reduced it to 48% and 5-day delay to 21%. Soggy breakdown was also severe with 14% of the fruit being affected. Two- and 5-day delays had no effect on occurrence of soggy breakdown, but CA storage increased it to 65%. Bitter pit was very rare and not affected by any of the treatments. These results demonstrate that in severe...


HortScience

Preplant soil-incorporated compost, mycorrhyzal innoculation (MI) at planting, and the combinatio... more Preplant soil-incorporated compost, mycorrhyzal innoculation (MI) at planting, and the combination of the two were tested for growth and yield increase of `Honeycrisp' apple trees on two rootstocks, M.26 and G.16. Compost was added at a rate of 0.51 m3 per tree. Within each main plot of compost or no compost were planted four trees with two on each rootstock. Noncompost plots were fertilized with N in year 1 and N, K, and Mg in year 4. The MI had no effect on growth until the third and fourth years after planting when annual trunk growth and tree height were greater than the untreated control. Compost increased trunk growth in the third and fourth years, but decreased growth in the fourth year when combined with MI. G.16 had greater trunk growth and tree height than M.26 in years 3 and 4. Fruiting was delayed by pruning at planting, so trees fruited for the first time in the fourth year. Bloom and yield were not increased by MI. There was more bloom and yield on G.16 than on M.2...

HortScience

The influence of red and blue light wavelengths was tested to improve the initial in vitro multip... more The influence of red and blue light wavelengths was tested to improve the initial in vitro multiplication of apple (Malus × domestica) rootstock cultivars Budagovsky 9 (B.9), Geneva 30 (G.30), and Geneva 41 (G.41). Single-node segments were established in semisolid Murashige and Skoog media and then transferred to proliferation media and cultured 40 days under white, red, or blue light irradiance. In a second experiment, G.30 was cultured under red, blue, or white light with and without gibberellic acid (GA3). The three rootstocks responded similarly under white light in terms of shoot number, length of the longest shoot, and the number of elongated shoots. Red light increased the number of shoots, length of the longest shoot, and the number of elongated shoots of B.9 and G.30 when compared with white or blue light. Red light increased the number of elongated B.9 and G.30 shoots to five per explant compared with one per explant under white light. In contrast, shoot growth of G.41 sh...

Journal of the American Society for Horticultural Science

Soft scald is an apple (Malus ×domestica Borkh.) fruit disorder that appears in response to cold ... more Soft scald is an apple (Malus ×domestica Borkh.) fruit disorder that appears in response to cold storage after about 2–8 weeks. It appears as a ribbon of dark tissue on the peel of the fruit, with occasional browning into the flesh. Several apple cultivars are susceptible to it, including Honeycrisp. The objectives of this study were to examine the cellular microstructure of fruit exhibiting soft scald and determine if any aspect of the peel microstructure at harvest could be indicative of future soft scald incidence. Light and electron microscopy were used to examine the peel microstructure of ‘Honeycrisp’ fruit that were unaffected or affected by soft scald. Tissue with soft scald had brown pigmented epidermal and hypodermal cells, whereas unaffected fruit peel epidermal cells were unpigmented. Cuticular wax of unaffected peel had upright wax platelets or clumps of wax, but peel surfaces with soft scald exhibited flattened granules and were more fragile than that of unaffected fru...

The Journal of Horticultural Science and Biotechnology, 2000

II International Organic Fruit Symposium, 2013

II International Organic Fruit Symposium, 2013