. 2020 Aug 22;10(9):1222. doi: 10.3390/biom10091222

Table 6.

Effects of preharvest application of cytokinins on postharvest quality of horticultural fruits.

Species	Cultivar	Factor(s) Investigated	Major Outcome(s)	Reference
Kiwifruit Actinidia deliciosa C.F.Liang and A.R.Ferguson.	Hayward	Effect of CPPU (0, 10, and 20 mg/L) sprayed at two application times (14 and 35 DAFB) on storage life	CPPU treatment had no positive effect and the storability of fruits was similar to the control	[215]
Kiwifruit Actinidia deliciosa	Hayward with cv. Matua as pollinizer (6:l)	Effect of CPPU (0 and 20 mg/L) on postharvest fruit performance (chlorophyll, glucose, fructose, sucrose, and starch content)	After 2.9 weeks of storage, CPPU-treated fruit had higher glucose, fructose, sucrose, and starch content. After 24.3 weeks (6 months) of storage, both control and CPPU-treated fruit had similar amount of glucose, fructose, sucrose, and starch. CPPU application stimulated the content of chlorophyll during storage	[216]
Cucumber Cucumis sativus L.	Zaokang	Effects of CPPU, NAA, and GA₄₊₇ at 100 mg/L on fruit quality after storage, 10 day	CPPU decreased weight loss, flesh firmness, and had no effect on fruit color. In addition, lower concentrations of phenolic and vitamin C were observed after 10 days of storage	[266]
Persimmon fruit Diospyros kaki Thunb.	Triumph	Effect of Superlon (mixture of GA₄₊₇ and BA) applied at 40 µg/mL once a month during three consecutive months of storage at 0°C on cracking and incidence of ABS disease	Superlon altered several host responses that affect ABS development. For example, 45% reduction in the cracked area and 40–50% reduction in naturally occurring ABS, while fruit firmness was not affected	[222]
Apple Malus domestica Borkh.	Delicious/M.26	Effect of CPPU (0, 5, 10, 15, and 20 mg/L) on fruit quality after 28 weeks storage (0°C)	CPPU-treated fruits were firmer than control treatment	[224]
Apple Malus domestica Borkh.	Hi-Early Delicious	Effect of promalin (0 and 25 mg/L) and CPPU (0, 5, 10, and 15 mg/L) on fruit quality after storage	After 7 days of storage at 20 °C, CPPU (5, 10, and 15 mg/L) increased flesh firmness	[224]
Apples Malus domestica Borkh.	Double Red Delicious/M.26	Effect of CPPU, TDZ (0, 5 and 10 mg/L), and promalin (0, 25 mg/L) on postharvest storage (fruit firmness) at 0 °C for 26 weeks and fruit quality (senescent breakdown, decay, bitter pit, and cork spot) at 20 °C for 2 weeks	Fruits from the treatments were firmer than the control. No treatment influenced senescent breakdown, decay or bitter pit, and cork spot	[226]
Apples Malus domestica Borkh.	Marshall McIntosh/M.9	Effect of CPPU (0 and 8 mg/L) applied over time on flesh firmness, fruit calcium content, and development of storage disorders following air storage at 0°C for 20 weeks	CPPU decreased flesh firmness, increased senescent breakdown, increased scald, and decreased fruit flesh calcium	[227]
Apples Malus domestica Borkh.	McIntosh/M.7	Effect of CPPU (0, 1, 2, 4, and 8 mg/L) applied at 5–6 mm on flesh firmness, fruit calcium content, and development of storage disorders following air storage for 20 weeks	Senescent breakdown and scald increased linearly with increasing CPPU concentrations. Fruit firmness and Ca content were not affected by CPPU treatment	[227]
Table grapes Vitis labrusca L.	Himrod	Effect of different concentrations (0, 5, 10, and 15 mg/L) of CPPU on berry shatter and rachis necrosis after cold (1°C) storage for 30 days	CPPU treatments reduced berry shatter, 10 days. Rachis necrosis was reduced (33–7% at day 20 and 44–12% at day 30) by 10 mg/L	[240]
Table grapes Vitis vinifera L.	Flame Seedless	Effect of CPPU (0, 1, 2, and 3 mg/L) on defects (loose berries, SO₂ damage, berry crack, decay, soft tissue breakdown, and external bruises) after six weeks (five weeks at –0.5°C plus one week at 7.5°C) of cold storage	CPPU (1, 2, and 3 mg/L) slightly reduced the total loose berries (%). Total cold storage defects (%) were not positively affected by any treatments	[242]
Table grapes Vitis vinifera L.	Redglobe	Effect of CPPU (0, 3, 4, and 5 mg/L) on defects (loose berries, SO₂ damage, berry crack, decay, soft tissue breakdown, and external bruises) after six weeks (five weeks at –0.5°C + one week at 7.5°C) of cold storage	CPPU (5 mg/L) increased the percentage of loose berries. Total cold storage defects (%) were not positively affected by any treatments when compared to the control	[242]
Table grapes Vitis vinifera L.	Crimson Seedless	Effect of CPPU (0, 2, 3, and 4 mg/L) on defects (loose berries, SO₂ damage, berry crack, decay, soft tissue breakdown, and external bruises) after six weeks (five weeks at –0.5 °C + one week at 7.5°C) of cold storage	An increase in CPPU dosage increase the percentage of SO₂ damage, bruises, and total defects. At 4 mg/L, these increases were significant when compared to the control	[242]
Grape vine Vitis vinifera L.	Thompson seedless	Effect of preharvest sprays of CPPU (0 and 5 mg/L), putrescine, GA, salicylic acid, ethephon, ascorbic acid, and calcium chloride on shelf life after 7 days of storage at ambient temperature	CPPU pre-treated fruits were firm. CPPU reduced unmarketable berries (%) and weight loss. CPPU increased berries adherence strength and reduced the percentage of berry shattering	[241]
Table grapes Vitis vinifera L.	Redglobe (seeded), Santiago	Effect of PGRs (0x GA₃, 1x GA₃, CPPU or 1x GA₃ + CPPU) on the firmness, shatter, hairline, splitting, hairline plus splitting, bleaching, and gray mold (Botrytis cinerea) incidence on berry cheek or at the berry base after 90 days at 0°C + 3 days at 20°C	CPPU had no significant influence on all the investigated parameters after storage period. Treatment with 1x GA₃ + CPPU influenced the shatter and incidence of gray mold (Botrytis cinerea) after storage	[244]
Table grapes Vitis vinifera L.	Thompson Seedless (seedless)	Effect of PGRs (2x GA₃, 8x GA₃, 2x GA₃ + CPPU, or 8x GA₃ + CPPU) on the firmness, shatter, hairline, splitting, hairline plus splitting, bleaching, and gray mold (Botrytis cinerea) incidence on berry cheek or at the berry base after 60 days at 0 °C + 3 days at 20 °C	All treatments had a significant effect on incidences of shatter, hairline, splitting, and gray mold on grapes after the storage period	[244]
Table grapes Vitis vinifera L.	Redglobe (seeded), Rancagua	Effect of PGRs (0x GA₃, 1x GA₃, CPPU or 1x GA₃ + CPPU) on the firmness, shatter, hairline, splitting, hairline plus splitting, bleaching, and gray mold (Botrytis cinerea) incidence on berry cheek or at the berry base after 90 days at 0 °C + 3 days at 20 °C	PGRs had a significant effect on fruit firmness, shatter, bleaching, and gray mold incidence after the storage period	[244]
Table grapes Vitis vinifera L.	Ruby Seedless	Effect of PGRs (2x GA₃, 8x GA₃, CPPU or 8x GA₃ + CPPU) on the firmness, shatter, hairline, splitting, hairline plus splitting, bleaching, and gray mold (Botrytis cinerea) incidence on berry cheek at the berry base after 60 days at 0 °C + 3 days at 20 °C	PGRs affected fruit firmness, shatter, hairline, and gray mold incidence	[244]

ABS = alternaria black spot; CPPU = N-(2-chloro-4-pyridyl)-N’-phenylurea; DAFB = days after full bloom; GA = gibberellins/gibberellic acid; NAA = naphthaleneacetic acid; PGRs = plant growth regulators; SO₂ = sulfur dioxide; TDZ = thidiazuron.