In order meet out the emerging consumer demand and challenges towards fruit production, there is the need to explore new interventions. One among that is use of new generation plant growth regulators in fruit crops. Plant growth regulators (PGR), recently name has been changed to plant bio-regulators (PBR’s) are defined as organic compounds, other than nutrients, that in small concentrations, affect the physiological processes of plants. There are five classical growth hormones which have the specific function in growth and development were already commercially exploited in fruit crops, but use of new generation growth regulators in fruit crops are recent and emerging trend. New generation PBR’s includes brassinosteroids, Jasmonate, salicylic acid, polyamines, karrikins and strigolactones and retardants such as 1-MCP and prohexodione-Ca. These are utilized in fruit crops starting from propagation to improving quality also including biotic and abiotic stress resistant. Hence, new generation plant growth regulators are an effective alternative for future fruit production combating major production challenges.

1. Role of New Generation Plant Bioregulators in
Fruit Crops
SINDHU M
PGS18AGR7897
Sr. M.Sc. (Agri.) Horticulture
UNIVERSITY OF AGRICULTURAL SCIENCES, DHARWAD
College of Agriculture, Vijayapur
Department of horticulture
Master Seminar I

2. Introduction
New generation PBR
Role of new generation PBR
Case studies
Conclusion

4. Biotic and abiotic
stress

5. 5
Plant bio regulators,
previously termed as plant
growth regulators.
In 1992 at Jerusalem in
the 7th international
symposium, the name
changed from plant
growth regulators to plant
bioregulators.

6. 6
Introduction
“Plant bio regulators
usually are defined as
organic compounds,
other than nutrients,
that used in small
concentrations, affect
the physiological
processes of plants”
Auxin
Cytokinins Gibberellins
Abscisic Acid
Ethylene
Brassinosteroids
Salicylat
es
Jasmonates
Strigolactones
New generation
Plant Bio-regulators ???

7. Brassino
steroids
(BRs)
Jasmonic
acid(JA)
1-MCP
Prohexa
dione-Ca
Polyamines
Salicylic
acid
NEW GENERATION
PLANT
BIOREGULATORS

8. Brassinosteroids(BRs)
About 70 BRs have been isolated from plants.
Mitchell et al. (1970) reported that stem elongation and cell
division were promoted by the treatment of organic extracts of
rapeseed pollen.
They are biosynthesized from campesterol
Structurally they are C27 – C28
Brassinolide, Castasterone, 24-epibrassinolide are most important
BRs because of their wide distribution and potent biological
activity(Bartwal et al.,2013)
Plant polyhydroxy steroids
Brassica napus pollen
Brassinolide (1979)

9. Role of Brassinosteroids
• promote apical dominance
• promote leaf senescence
• enhance seed germination
• increase the production of ethylene
• inhibit the formation of stomata
• prevent premature abscission of fruit
• increase resistance to freezing
• Pollen elongation and pollen tube growth

10. Jasmonic Acid (JA)
• It’s role in plant defence was first shown by Farmer & Ryan
(1990)
• Highest in flowers, reproductive tissues, young leaves and lowest
in roots and mature leaves.
• Methyl jasmonate and cis-jasmone are well known in the perfume
industry as fragrant components of the essential oils of jasmine
Linolenic acid
Jasmine flower
Jasmonates

11. Role of JA
• Plant growth and development.
• Growth inhibition and senescence
• Flower development
• Leaf abscission.
• Wounding of plants
• Systemic acquired resistance
• Defense responses against environmental stress
• Regulate ethylene biosynthesis and Influence aroma volatile
• Decreased low temperature injuries.

12. Salicylic Acid
• Colorless crystalline organic acid
• Systemic Acquired Resistence
• Cross talk with jasmonates
Ortho-hydroxybenzoic acid
Saliciline
White willow (Salix alba).

13. Role of salicylic acid
• Abiotic stress
• Thermogenesis
• Seed germination
• Phenolic compounds exert their influence on physiological
and biochemical processes including, photosynthesis, ion
uptake, membrane permeability, enzyme activities, flowering
and growth and development of plants.
• SA is involved in mediating in plant defense against
pathogens

14. Polyamines
• Biological compounds and ubiquitous in living organisms.
• Lower molecular weight.
• Aliphatic nitrogen groups.
• At cellular PH values, acts as cations (polycationic compound)
• A polyamine is an organic compound having two or more
primary amino groups–NH.
• They stimulate many reactions involved in the synthesis of
DNA, RNA and proteins.
• Polyamines are essential for all living organisms and without
the ability to synthesize polyamines, living cells will not
survive.

15. Most frequently found polyamines are:
– Putrescine
– Spermidine
– Spermine
– Cadaverine

16. Role of polyamines
• Cell division and root initiation
• Tuber formation
• Embryogenesis
• Flower development
• Regulate fruit ripening
• Abiotic stress
• Reduce PLW

17. 1-MCP
• Synthetic cyclic oliphene, gaseous PBR.
• Interacts with ethylene sensitive site
• Delays fruit softening and improves quality
• Maintains firmness
• Decreases storage disorders
• Delays chlorophyll degradation

18. Prohexadione – Ca
• Carboxylic group.
• Anti- gibberellin.
• It is a mimic of 2-oxoglutaric acid & ascorbic acid
• Reduces longitudinal shoot growth by blocking dioxygenases
• Reduces alternate bearing
• Reduces ethylene formation

20. Table 1: Effect of 22(S), 23(S)- Homobrassinolide on adventious root
formation in grape rootstock.
rootstock 22(S),
23(S)-
homobrass
inolide
(ppm)
Root
number
Root
developme
nt(0-4
scale)
Shoot
length
(cm)
Cutting
rooted (%)
Cutting
sprouted
(%)
1103
Paulsen
Control 3.70 1.66 8.79 70.83 90.00
0.05 4.23 2.48 12.81 85.33 97.50
0.10 3.64 1.59 12.11 76.67 90.83
0.15 3.63 1.88 11.65 80.00 93.34
0.25 3.99 2.02 12.67 82.50 93.33
Mean 3.84 1.92 11.60 79.17 93.00
Turkey Kalpan and Gokbayrak., 2012
Cuttings were dipped in BRS

21. Table 2: Effect of polyamines treatments on flowering and yield
of strawberry
Treatment Number of flowers
per truss
Yield per plant(g)
Selva Paros Selva Paros
Control 3.2 4.25 180 208
Spermidine (0.5mM) 4.35 5.725 272 289
Spermidine (1mM) 6.3 7.125 442 486
Spermidine(1.5mM) 8 7.825 544 726
Putrescine (0.5mM) 5.4 6 255 374
Putrescine (1mM) 6.9 8.125 414 570
Putrescine (1.5mM) 7.7 8.7 501.5 713
Iran Movahed et al.,2012
Sprayed at 4-5 fully expanded leaves and beginning of flowering

22. Effect of brassinosteroids on fruit yield and quality characteritics of
‘tak danehe mashhad’ sweet cherry
Stages of application of BRs.
1. Swollen bud stage
2. Beginning of fruit set
3. Swollen bud stage + Beginning of fruit set
4. Beginning of fruit set + 10 days pre harvest on sweet cherry
Iran Roghabadi and Pakish., 2014

23. Table 3: Effect of brassinosteroids on fruit yield and quality characteritics of
‘tak danehe mashhad’ sweet cherry
Treatment Stage Number of
fruits per 1cm2
shoot (g)
Fruit
weight
Yield per 1cm2
shoot (g)
Firmness
(kg cm2)
Ascorbic acid
(mg100ml-1)
anthocya
nin
Control - 29.9 6.56 196.81 1.9 9.2 79.24
Br
(0.25mgl-1)
1 50.1 5.4 270.16 1.9 9.4 82
2 42.59 6.73 286.68 2.8 11.8 95.28
3 33.16 6.91 229.16 2.8 11.4 88.24
4 33 6.83 225.57 2.1 14.9 124
Br
(0.5mgl-1)
1 59.15 5.5 325.24 2 9.5 89
2 45.49 6.91 315.58 2.9 13.2 110.58
3 36.79 7.12 262 3.2 14.5 94
4 36.13 7 253.51 2.2 15.1 126.82
Br
(0.75mgl-
1)
1 78.83 6 475.86 1.9 9.7 88.23
2 59.31 7 419.14 2.9 14.8 124.25
3 42.32 7.18 306.56 2.9 14.6 103.81
4 41.83 7.23 300.68 3.3 15.7 152.69
Iran Roghabadi and Pakish., 2014

24. Treatments Number of
hermaphro
dite flowers
Fruit weight
(g)
Yield
(kg/tree)
TSS (°B) Acidity(%) Reducing
sugar
Control 190.33 240.19 44.55 15.39 0.30 3.29
SA(1500ppm) 249.67 280.26 66.46 18.13 0.27 3.38
SA(2000ppm) 335.00 322.24 73.59 18.59 0.23 3.95
SA(2500ppm) 196.33 251.50 48.79 17.49 0.25 3.87
HA (0.1%) 240.00 248.64 53.52 16.78 0.29 3.66
HA (0.2%) 193.67 284.61 60.46 17.25 0.27 3.57
HA (0.3%) 242.67 294.55 56.20 17.37 0.25 3.42
S.E. ± 19.67 14.17 4.25 0.57 0.01 0.14
C.D (P=0.05) 60.62 43.66 13.11 1.77 0.03 0.43
C.V. (%) 14.48 8.94 12.78 5.75 7.39 6.71
Table 4: Effect of SA and humic acid on flowering, fruiting, yield and quality
parameter in mango cv. Kesar
Navasari flower bud initiation stage (3rd week of October) Ngullie et al., 2014

25. TREATMENTS
T1: Hand pollination (Control)
T2: GA3 at 1000 mg /L
T3: GA3 at 1500 mg /L
T4: BRs at 0.5 mg /L
T5: BRs at 1.0 mg /L
T6: GA3 at 1000 mg /L + BRs at 0.5 mg /L
T7: GA3 at 1000 mg /L + BRs at 1.0 mg /L
T8: GA3 at 1500 mg /L + BRs at 0.5 mg /L
T9: GA3 at 1500 mg /L + BRs at 1.0 mg /L
Effect of GA and BRs on fruiting, yield and quality of sugar apple
during 2017 and 2018 season
Sprayed at anthesis stage for 5 weeks (once in week)
Egypt Mostafa and Kotb, 2018

26. Treat
ments
Fruit set(%) Fruit retention
(%)
Yield (kg/tree) Fruit weight TSS(%)
2017 2018 2017 2018 2017 2018 2017 2018 2017 2018
T1 78.33 80.33 82.67 82.67 100.0 101.65 232.91 234.13 28.00 28.40
T2 66.00 67.67 68.33 70.33 93.30 97.60 222.96 222.96 27.53 27.00
T3 79.33 82.67 82.33 81.67 106.30 110.70 231.25 232.30 27.23 26.33
T4 74.00 75.67 76.67 76.33 100.37 101.90 234.73 235.50 28.10 28.60
T5 79.33 80.33 79.00 80.00 106.65 109.50 239.56 238.57 29.17 28.70
T6 80.00 83.67 82.67 81.67 111.34 110.55 235.66 233.19 27.80 27.70
T7 73.67 80.67 75.33 75.00 102.13 108.80 232.16 233.86 27.75 27.53
T8 71.00 77.33 72.67 75.33 98.60 105.80 234.06 233.50 27.63 27.13
T9 74.67 80.00 76.67 77.33 102.32 108.51 235.80 235.63 27.60 27.07
LSD
(0.05)
2.47 2.26 1.92 1.87 1.31 1.37 3.044 2.82 0.50 0.84
Table 5: Effect of GA and BRs on fruiting, yield and quality of sugar
apple during 2017 and 2018 season
Egypt Mostafa and Kotb, 2018

27. Treatment Length of canes Fruit number
per cane
Yield per cane Soluble solids
Control 266 147 537 10.5
Pro Ca 211 205 881 11.3
R 249 193 800 11.3
R+Pro Ca 250 218 864 11.0
2R 253 173 766 10.7
Table 6: Prohexadione-Ca and young cane removal treatments
control growth, productivity, and fruit quality of the Willamette
raspberry
Serbia Milena et al., 2012
i. Untreated
ii. ProCa (treated with 2 ProCa)
iii. R (first removal of young canes)
iv. R+ProCa (young cane removal and 2 ProCa)
v. 2R (second young cane removal)
Foliar spray:
1st at growth of primocane(30cm
height)(100ppm).
2nd 3weeks after 1st spray(200ppm).

28. Table 7: Effect of SA on alleviating chilling injury and extending shelf life of
mango fruits during cold storage
Parameters Treatments Storage period (days)
5 10 15 20 25 30
Weight loss (%) Control 3.10 6.56 9.85 13.40 15.62 17.63
SA(1mM) 2.33 4.98 7.75 10.94 12.92 16.06
SA(2mM) 2.19 4.72 7.67 10.21 12.00 15.36
Chilling injury Control 0.60 1.04 1.37 1.65 2.00 2.45
SA(1mM) 0.35 0.94 1.20 1.38 1.79 2.17
SA(2mM) 0.25 0.86 1.11 1.21 1.45 1.85
Decay loss(%) Control 0.00 1.00 4 7 12.0 16.0
SA(1mM) 0.00 0.00 1.50 2.30 5.30 8.40
SA(2mM) 0.00 0.00 0.00 1.50 3.40 6.80
IARI, New Delhi Barman and Asrey, 2014
upto 30 days at 8°C plus 3days ambient condition (25±2°C and 60-65% RH)

29. Table 8: Effects of Salicylic acid on fungal decay, overall quality
index and ethylene production of strawberry var. selva
Treatment
SA (mmol-1)
Fungal decay index Overall quality
index
Ethylene (NL kg h1 )
0 5 1 32.07
1 2.9 2.8 15.69
2 2.57 3.23 10.42
4 2.6 3 17.13
Iran Babalar et al., 2007
Dipping fruits in SA solution

30. Fig 1: Effect of post harvest treatments of putrescine on storage of mango cv. Langra
PAU, Ludhiana Jawandha et al., 2012
T1: 1.0mM/L
T2: 2.0mM/L
T3: 3.0mM/L
T4: control(0)
Fruits are stored at
13°C with 90-95%RH

31. Changes in chilling injury index
Fig 2: Effect of methyl jasmonate on reduce chilling injury in
guava fruits
Mexico Gonzaalez et al., 2003

32. Table 9: Effect of 1-methylcyclopropene (1-MCP) on quality of pear
fruits
Treatme
nts
PLW(%) Firmness (lb
force)
Sensory quality TSS (%) Total sugar
3 6 3 6 3 6 3 6 3 6
0 10.4 9.0 8.7 9.1 5.1 5.2 11.9 12.0 7.6 7.6
500ppb 6.9 6.6 10.8 11.2 7.0 7.0 13.5 13.5 8.8 8.5
750ppb 6.5 6.0 10.9 11.2 7.5 7.6 13.9 13.8 9.0 8.6
1000ppb 6.0 5.5 11.5 12.0 8.0 8.0 14.2 14.5 9.2 9.8
CD
(p>0.05)
0.4 0.3 0.2 0.2 0.3 0.2 0.1 0.4 0.7 0.7
PAU, Ludhiana Mahajan et al., 2009
Fruits were exposed to 1-mcp gaseous vapour in an air tight chamber at 200C for 4h.

33. Table 10: Effect of MJ on quality of strawberry var. Selva and
Queen Elisa
Treatment TSS (Brix %) Antocyanin Vitamin C
Selva Queen
elisa
Selva Queen
elisa
Selva Queen
elisa
Control 6.8 7.9 34.25 26.5 70.1 71.7
0.25Mm 7.4 8.9 35.42 27.1 71.4 73.1
0.5Mm 7.8 9.3 36.31 27.9 73.2 74.5
1Mm 8.3 9.5 36.9 28.5 75.4 76.8
Iran Lolaei et al.,2013
Foliage-berry spray(light pink stage), 2 time application at 5days interval.

34. CONCLUSION
 New generation bio-regulators can be an effective alternative for enhancing yield and quality
of fruit crops
 Biotic and abiotic stress resistance can also be achieved using new generation PBR’s.
 These are natural and safe growth regulators which exhibits a high potential in controlling
postharvest losses.
 Some of the new genereation PBRs could cross talk with other harmones and have synergistic
effect between them.

35. THANK YOU