RECENT ADVANTAGE OF PLANT GROWTH REGULATORS IN VEGETABLE CROPS

2. HEMVATI NANDAN BAHUGUNA GARHWAL UNIVERSITY
(A CENTRAL UNIVERSITY )
SRINAGAR UTTARAKHAND – 246174
DEPARTMENT OF HORTICULTURE
ASSIGNMENT
TOPIC – RECENT ADVANTAGE OF PLANT GROWTH REGULATORS IN VEGETABLE
CROPS
SUBBITED TO:- SUBBMITED BY
DR. T.S. BISHT HEMANT GURJAR
ASST. PROFESSOR M.SC. HORTICULTURE

3. TABLE CONTENT :-
1. INTRODUCTION
2. DEFINATION OF GROWTH
REGULATORS
3. CLASSIFICATION AND FUNCTIONS
OF PGRS
4. ROLE OF PGRs IN VEGETABLES
CROPS
5. RECENT ADVANCES OF PLANT
GROWTH REGULATORS IN
COLECROPS

4. INTRODUCTION-
❑ Cole crops is a general term used to describe several vegetables in the mustard family. This group of
vegetables includes cauliflower, cabbage, knol- khol, broccoli, Brussels sprouts, kale and Chinese cabbage
(see under leafy and salad vegetables). All the crops are cultivated varieties of the species Brassica
oleracea. Cole crops have one of the oldest histories of European vegetables and are widely grown
throughout the world, including tropical, subtropical and temperate regions. While cauliflower and
cabbage are regarded as major vegetables, the rest especially in India are considered minor vegetables.
Cole crops are rich source of vitamins A and C.
❑ . Plant growth regulators are defined as the natural or synthetic biological substances which influence
the overall growth and development of plants. These are collectively called as Plant Growth Regulators
or Plant Growth Hormones.
❑ There are different types of Plant Growth Regulators,

5. DEFINATION OF GROWTH REGULATORS :-
Defiend growth hormons as substance which are synthesized in particular cell and
are transfer to other cells where in extremely small quantities influence the
development process.
Plant growth regulators are the chemical substances which govern all the factors of
development and growth within plants. Some other names used to refer to it are
phytohormones and plant growth hormones.Phytohormones are organic compounds which
are either synthesized in laboratories or produced naturally within the plants. They
profoundly control and modify the physiological processes like the growth, development, and
movement of plants.

6. CLASSIFICATION OF GROWTH REGULATORS
GROWTH REGULATORS
• Auxin
• Gibberellins
• Cytokinnis
• Etheylene
• Absecisic acid
EXAMPLE
• IAA , IBA , NAA N 2.4-D
• Gibberellins acid ( GA, GA3, GA7
• Kinetine , zeatin,
• Ethylene , ethephone , ethrel

7. MAJOR GROUP OF PLANT GROWTH REGULATORS
AUXINS
GIBBERELLINS PLANT GROWTH REGULATORS
CYTOKININS
ETHYLENE PLANT
GROWTH
ABSCISIC ACID INHIBITORS

8. Characteristics of Plant Growth Regulators:-
Plants growth hormones or plant growth regulators exhibit the following characteristics
➢ Differentiation and elongation of cells.
➢ Formation of leaves, flowers, and stems.
➢ Wilting of leaves
.
➢ Ripening of fruit.
➢ Seed dormancy, etc.

9. PLANT GROWTH PROMOTERS
AUXIN:-AUXINS ARE ONE OF THE MOST IMPORTANT PLANT HORMONES. THESE PLANT GROWTH REGULATORS
ARE GENERALLY PRODUCED AT THE POINTS OF STEMS AND ROOTS FROM WHERE THEY ARE TRANSPORTED TO
OTHER PARTS OF THE PLANTS. THESE PLANT HORMONES INCLUDE BOTH NATURAL AND SYNTHETIC SOURCES
NATURAL PLANT SOURCES,
• Indole-3-acetic acid and { IAA }
• indole butyric acid { IBA }
SYNTHETIC SOURCES
• naphthalene acetic acid { NAA }
• 2, 4-dichlorophenoxyacetic acid { 2.4. D }
malik c.p.1999 advance in plant hormones research

10. FUNCTIONS OF AUXINS
NAA is synthetic plant hormone in the auxin family and is an ingredient in Many commercial plant rooting
horticultural product.
This rooting agent is useful for Vegetative propagation of plants, from stem and leaf cutting, plant tissue
culture.. It has also been Understood to prevent pre mature dropping and thinning of fruits from stems.
Apical dominance:-
✓ Promotes callus and root formation in cutting
✓ Induction of flowering
✓ Development parthenocarpy
✓ Inhibition of prolonged dormancy
✓ Delays leaf abscission

11. : Gibberellins- They are acidic and are denoted as follows – GA1, GA2, GA3etc.
➢ . Second most important growth hormones
➢ Gibberellin produced in the shoot apex mainly in the leaf primordial leaf
( leaf bud ) and root system . Hence they translocate easily in the plant in both
direction
➢ Break bud and seed dormancy.
➢ Promote bolting in cabbages and beet.
➢ STEM GROWTH
Chauhan and Singh (1970)

12. Cytokinins:-
They are involved primarily in cell growth and differentiation but also affect
• cell division
• Cell enlargement
• Induced flowering in short day plant
• Dormancy of certain light sensitive seed such as lettuce can also be broken
by kinetin treatment
• Delays leaf senescence
• Inhibit apical dominance and help in growth of lateral buds
(Chhonkar and Singh, 1963; Badawi and Sahhar, 1978).

13. Plant Growth Inhibitors :-
Abscisic acid :- It is a growth inhibitor, which was discovered in the 1960s. This growth inhibitor
is synthesized within the stem, leaves, fruits, and seeds of the plant. Mostly, abscisic acid
serves as an antagonist to Gibberellic acid. It is also known as the stress hormone
Functions of Abscisic acid
▪ Promote tuberization
▪ Induced senescence of leaves abscission of leaves flowers and fruit,
▪ It induced dormancy of buds and seed as opposed to gibberellins , which breaks dormancy ,
▪ It inhibits seed germination and development
▪ ABA also plays importance role in controlling stomata opening and closing

14. Ethylene:-.
Ethylene is synthesized by the ripening fruits and ageing tissues.
Functions of Ethylene:-
Ethylene is the most widely used plant growth regulator as it helps in regulating many physiological
processes.
➢ Promotes sprouting of potato tubers.
➢ Enhances respiration rate during ripening of fruits.
➢ Used to stimulate the ripening of fruits. For example, tomatoes and citrus fruits.
➢ Induction of femaleness
Hunter et al., 1999

15. ROLE OF PGRs IN VEGETABLES CROPS:-
Seed germination :-
➢ in tomato pre sowing seed treatment with 100 ppm , IAA ,IBA, and NAA enhanced the
seed germination
➢ In muskmelon soaking of seed in ethephon at 480 mg / liter of water for 24 hours
improve germination in muskmelon at low temperature
➢ pre – sowing treatment of seed with GA3 and KNO3 @ 50 ppm enhanced the germination
of endive and chicory respectively
➢ IAA, NAA @ 20ppm enhances seed germination in okra,

16. SEED DORMANCY :-
• Seed dormancy is main problem in potato and lettue
Chemicals which have been reported to breck the rest period are GA3 ethylene chlordydrin and thiourea
• lettuce is another vegetable in whichg treatment with GA3 or cytokinin has been reported to break seed
dormancy induced by high temperature
• Breaking the dormancy in potato comprise the vapour heat treatment with ethylene chlorhydrin ( 1 litter per 20
q ) followed by dipping in thiourea ( 1% sol.) for 1 h & finally in GA ( 1 mg / 1 ) for 2 second .

17. FLOWERING :-
• NAA 50ppm has been reported to induce to induced early flowering in paprika.
Plants sprayed with 300ppm GA3 were earlies to flower and recorded highest number of fruit and yield per plant in tomato
Gibberellic acid has been reported to induced early flowering in lettuce
Sex expression :-
• The treatment with growth regulators has been found to change sex expression in cucurbits okra pepper ,
GA3 ( 10-25ppm ) , IAA ( 100ppm ) and NAA ( 100ppm )
When sprayed at 2-4 leaf stage in cucurbits , then they have been found to increase the number of female flower ,

18. Parthenocarpy :-
Plant growth regulators help to stimulate the fruit development without fertilization (
parthenocarpy )
Stimulation of fruit set :-
Poor fruit set is a major problem in tomato , brinjal , and chilis which is frequently caused by
adverse weather condition during flowering ,
Hybrid seed production :- bioregulators have also been used for maintenance of
gynoecious cucumber ,
Fruit ripening :- application of ethephon at 100 mg /1 at truning stage of earlist fruit
induced early ripening of fruit increasing the early fruit yield by 30-35%

19. Fruit yield :-
➢ Tomato :- spraying with 60ppm GA3 , 10 days before transplanting increased the yield per ha of variety
rooma
➢ Brinjal :- foliar spray of 2.4-D @ 4ppm gave the highest yield of brinjal .

20. RECENT ADVANCES OF PLANT GROWTH REGULATORS IN COLECROPS
❖ Foliar spray of GA3 and NAA was given at 30 and 45 DAT of cabbage. Looking to the results, it was noticed that GA3
60ppm significantly increased the plant height (33.26 cm), number of leaves (21.48), plant spread (55.59 cm), stem
diameter (3.05 cm), plant weight (2.44 kg), head weight (1.73 kg), head diameter (18.88 cm ) as well as head yield
(51.26 t/ha) than the other treatments and control.
JAGDEEP CHAURASIY 1 *, M. L. MEENA2 , H. D. SINGH 2 ,A.ADARSH1
❖ GA3 50ppm spray is the highest yield ( 104.93t/h) was obtain from .1.5% starter solution which was significant
different from other solutions, and the lowest yield (66.86 t/ha) was recorded from the control.
R. Roy, M.A. Rahim and M.S.Alam

21. ❑ Foliar spray of GA3 30 mg L-1 + kinetin 30 mg L1 treatment gave maximum growth and yield of
sprouting broccoli
Manjit Singh, D. K. Rana*, J. M. S. Rawat and S. S. Rawat
❑ The maximum plant height(31.5 cm), number of leaves (16.6/plant), number of main fingers (12.0/main curd),
main curd length (21.3 cm),
main curd diameter (19.3 cm), main curd weight (668.0 g/plant) and yield (24.5 t/ha) was found from the
application of 50 ppm GA3 while the minimum from control.
R.K. Sikder, H. Mehraj and A.F.M. Jamal Uddin
❑ NAA @ 180 ppm to the sprouting broccoli significantly increased the plant height (58.32 cm),
number of leaves (25.85), leaf area (1255.35 cm2 ), chlorophyll content in leaves (2.99 mg/100g),
total yield per plot (6.42 kg), total yield per hectare (198.25 q),
Pooja Chanwala,A.K. Soni*, Deepika Sharma and Gulab Choudhary

22. ❖ Foliar spray of GA3 at 50 mg/l in cauliflower gave better results for diameter of curd (17.78 cm), length of stalk (5.22 cm),
net weight of curd (3.53 kg/plant), curd yield (12.5 kg/plot) and required minimum days to 50 % marketable curd .
Sitapara et al., (2011).
❖ gibberellic acid @100ppm and boric acid at 0.2 per cent were found better for growth attributes (viz, plant height, number of
leaves, stem length, stem diameter, days taken for marketable curd etc.), yield attributes (viz, diameter, volume and weight of
curd) and ultimately the early curd yield of cauliflower cultivar “Snowball-16”
H.H. SITAPARA, N.J.VIHOL1 , M.J. PATEL1 AND J.S. PATEL1