Introduction
- The life cycle of mango may be divided into five stages: the nursery,
the establishment in the field, the non-bearing period, the bearing
period, and the aging trees.
- The nutritional requirements in each of these periods differ.
- Speedy growth of root-stock seedlings and proper establishment of
grafts are the chief objectives in nursery.
- At the time of establishment in the field, it is necessary to ensure
least mortality.
- The main requirements in the pre-bearing age are rapid growth of the
tree and the development of a sound and strong framework.
- During the bearing period, good cropping, regular bearing and high
quality of fruit are expected.
- When the trees are aged, rejuvenation or reinvigoration is desired.
- These objectives have to be met by different prescriptions.
Manuring Schedules for Mango Suggested by Various Workers
Sl.No.
|
Recommendations (All doses are in kg, if
not otherwise stated
|
References
|
(a) Nursery stage
|
1.
|
Liquid manure @ 225 g plant-1 at fortnightly intervals
starting 3 months after planting stones.
|
Cheema et al., 1954
|
2.
|
Grower mixture (4-7-5 or 4-9-3 with 25-30% organically derived
N @ of 3.5 to 7.0 g tree-1
|
Singh, 1960
|
3.
|
AS or CAN at the rate of 22 to 27 kg N ha-1 once or
twice
|
Singh, 1967
|
(b) Pit manuring
|
1.
|
50 FYM + 2.5 BM + 4.0 WA should be mixed with soil of the pit
while filling.
|
Burns and Prayag, 1921
|
2.
|
Lower 60 cm of the pit 15 to 20 FYM + 3.0 BM Upper 30 cm of the
pit 5.0 FYM + 1.0 to 1.5 B.M. + 1 kg NOC
|
Allan, 1935
|
3.
|
5-10 FYM, 6 to 12 months before planting
|
Naik, 1949
|
4.
|
12.5 FYM + 0.75 BM + 1.25 WA
|
Chemma et al., 1954
|
(c) Non-bearing stage
|
1.
|
10 FYM + 2.5 BM + 5.0 WA (5 FYM + 0.5 BM + 1.0 WA)
|
Burns and Prayag, 1921
|
2.
|
2.5 to 5.0 FYM + 1.5 NOC + 1.5 SP/BM + 0.38 K2SO4
|
Allan, 1935
|
3.
|
18.7 FYM + 2.4 MB/SP + 0.3 AS + 0.5 lime + 0.5 WA/K2SO4
(3.7 FYM, 0.5 BM + 0.3 AS + 0.3 lime 0.9 WA or 0.3 K2SO4)
|
Roy, 1953
|
4.
|
75 g N + 110 g P2O5 + 55 g K2O;
40 to 80% of N should be organically derived
|
Singh, 1967
|
5.
|
12.5 FYM + 2.5 BM + 5.0 WA (5.0 FYM + 0.5 BM + 1.0 WA)
|
Mari Gowda, 1974
|
6.
|
9.0 FYM + 3.00 BM + 5.0 WA (5.0 FYM + 0.5 BM + 0.91 WA)
|
Singh, 1969
|
7.
|
4.7 to 18.7 FYM + 0.3 to 0.5 AS
|
Singh
and Jawanda, 1961
|
(d) Bearing stage
|
4 to 6 year old |
1.
|
18.7 to 37.4 FYM + 0.5 to 1.0 AS
|
Singh and Jawanda, 1961
|
2.
|
22.5 to 50.0 FYM + 1.0 - 1.38 AS
|
Singh, et al., 1962
|
3. |
60 - 100 FYM + 2.0 - 4.00 AS + 2 - 3 SP
+ 0.25 - 1.00 MOP |
Parsai, 1974 |
5th year onward
|
4. |
10-20 FYM + 0.72 N + 0.28 P2O5 + 0.60 K2O
|
Mari-Gowda, 1974
|
6 to 9 year old |
5. |
2.5 to 3.25 AS + 2.50 SP + 1.5 SOP |
Singh, 1967 |
7 to 9 year old |
6. |
65 to 87 FYM + 1.5 - 2.0 AS
|
Singh et al., 1962 |
7 to 11 year old |
7. |
37 to 55 FYM + 1.0 to 2.0 AS |
Singh and Jawanda, 1961 |
10 year onwards |
8.
|
50 FYM + 7.5 BM + 15 WA
|
Burns and Prayag, 1920
|
9.
|
25 FYM +7.5 BM + 2.5 AS
|
Waggle, 1931
|
10.
|
20 to 22.5 FYM + 2.0 NOC + 6 mixture of BM/SP with SOP
|
Allan, 1935
|
11.
|
730 g N 180 g P2O5 + 680 g K2O
|
Roy et al., 1951
|
12.
|
750 g N 185 g P2O5 + 680 g K2O
|
Mallik and De, 1951
|
13.
|
100 - 200 FYM + 2.25 - 4.00 AS
|
Singh et al., 1962
|
14.
|
50 FYM + 7.5 BM + 15 WA
|
Bhandari & chinnapa, 1963
|
15.
|
50 FYM + 7.5 BM + 15 WA + 2 - 3 AS
|
Ditto, 1966
|
(e) Other basis
|
1.
|
37.5 FYM + 10 BM + 3.00 AS
|
Waggle, 1931
|
2.
|
80 g N 120 g P2O5 + 80 g K2O
year-1 age
|
Prasad % Saran, 1969-71
|
3.
|
- General manuring @ 10 cart loads of FYM every year
- Heavy fruiting year - 50 FYM + 7.5 BM + 15 WA
|
Gandhi, 1955
|
4.
|
20 NPK and Mg mixture in the proportion of 6:3:10:3 to compensate
for the loss due to removal of 1000 kg of fruit
|
Singh, 1962
|
- AS = Ammonium sulphate, BM = Bone Meal, MOP = Muriate of Potash, NOC
= Neem Oil Cake, SOP = Sulphate of Potash, SP = Super Phosphate, WA
= Wood Ash.
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Top
Nursery and Transplantation Stage
Nursery Stage
- It is usual to keep the nursery fields rich in humus for improving
their water-holding capacity and promoting root growth.
- Normally, 25-40 tonnes of farmyard manure is applied to a hectare
where mango stones are sown or the grafts are planted after severance
from the trees.
- When pots are used, they are generally filled with a mixture of leaf
mould, top-soil and sand in the ratio of 8:8:1.
- For improving the growth of seedlings, light doses of inorganic fertilizers,
viz., ammonium sulphate and calcium ammonium nitrate, at the rate of
22 to 27 kg. of N or 247 to 309 kg. of fertilizer per hectare are applied
either once or twice at an interval of about 20 days.
- Where the application of farmyard manure attracts white ants and causes
damage, it is advisable to apply Eldrin or Gammexane in suitable doses.
Transplation Stage
- It is generally advisable not to apply any manure at the time of planting.
Almost all soils selected for planting mangoes have enough nutrients
available to support growth of the trees at least for a year.
- If the soils are too poor to sustain them even over such a short period,
they are best not utilized for mango cultivation.
- Further, the application of manure at the time of transplantation
can prove harmful.
- It may attract white ants.
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Non-Bearing Stage
- This stage extends from the time the plant gets established in the
field.
- In this period the need for calcium, nitrogen and phosphorus is high.
- Potassium is also required in reasonable amounts.
- In soils with a high calcium content and pH ranging from 7.0 to 8.0,
surface application of calcium may not be necessary but in soils where
pH is low, 5.5 to 6.5, it may be necessary to add calcium in the form
of dolomitic lime.
- The quantities required to be applied would depend upon the soil reaction
and, in certain cases, may run as high as 2,200 to 3,300 kg. Per hectare.
- During the non-bearing period nitrogen is particularly required in
sufficient amounts to induce vigorous growth.
- It would be better if some part of N is derived from organic matter
so that soil texture, moisture-holding capacity and ultimately the growth
and development of roots improve.
- Phosphorus would be required to cope with high respiration rates and
for translocation of carbohydrates.
- Potassium would also be required to meet the need of photosynthesis
but its need during non-bearing period would be comparatively less than
that during the bearing period when it is required for sugar and starch
synthesis in greater quantities.
- These needs will be met roughly in N, P and K are applied at the rate
of 75, 110 and 55 gm. Of N, P2O5 and K2O
for each year of age of the tree with 40 to 80 per cent N derived from
an organic source.
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Bearing Stage
- The mango is a terminal bearer.
- The fruit-bud differentiation takes place about four to five months
before flowering.
- In the year of heavy flowering and fruiting the vegetative growth
is limited which, in turn, affects the next crop, because the shoots
from the earlier flushes in spring are the ones to flower in the next
spring.
- If the early flush of vegetative shoots is not put out be the tree
owing to heavy flowering and fruiting, there would be very few mature
shoots available at the time of bud differentiation or formation of
floral buds; hence, there would be no flowering in the next spring.
- The manuring of the bearing tree is thus faced with certain complex
problems which the grower must keep in mind in order to adjust his practices
fruitfully.
- In heavy crop years, thus, the objectives should be:
- securing sufficient vegetative growth early in
the season for the next year's cropping,
- maintenance of tree vigour, and
- Improving the quality of fruit.
These can be partially achieved in one of the two ways:
- by application of a heavier dose of nitrogen a little
earlier than flowering in the 'on' year to initiate vegetative growth,
and
- The suppression of bud differentiation in the 'off' year
so that the cropping in the 'on' year is reduced and the production
of vegetative shoots is promoted.
- Deeping these problems in view, the manurial needs of
bearing trees have been experimented with at several places in India.
- Based on the results of such investigations the following
schedule of manuring for a bearing mango tree is recommended.
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Top
Foliar Feeding
- Foliar sprays of macronutrients have been used to supplement their
soil applications to obtain quick response and to correct deficiencies.
Macronutrients
- Urea has been sprayed singly or in combination with superphosphate
and/or potash or growth regulators.
- The recommended spray of 4 per cent urea which resulted in increased
length of terminal shoots, number of leaves per shoot, leaf area per
shoot, leaf N and water content in Langra snd Chausa cultivars and did
not cause any injury.
- 2 to 4 per cent urea shortened the p of flowering by 5 to 7 days
and improved yield, and flower bud formation was depressed by 2 per
cent urea.
- The reduction in duration of flowering and increase in number of flowers,
fruit set and fruit retention by urea spray.
- The higher fruit yield is obtained by two sprays of 4 per cent urea
at full bloom and observed leaf scorching by 6, 8 and 10 per cent concentrations.
- In both these studies, 6 per cent concentration was suggested as the
critical limit when leaf injury was noticed.
- The mechanism of injury either through ammonia toxicity or due to
biuret has not been established.
- The vegetative growth increased in the three cultivars, Langra, Deshehari
and Totapari as the concentration of urea spray was increased from 2
to 6 per cent.
- Fruit weight was maximum by 4 per cent urea in Deshehari and Totapari
whereas it was the highest by 6 per cent concentration in Langra.
- Fruits from urea sprayed trees remained darker green than in the control.
- Concentrations of 8 to 10 per cent urea delayed maturity by 10 to
15 days.
- Results of effect on fruit weight have not been consistent.
- 4 percent urea resulted in the highest TSS, total sugars and ascorbic
acid in fruits whereas acidity increased concentration of urea from
2 to 6 per cent.
- Use of combined spray of N and P has been found to be more beneficial
presumably because of increased recovery of P in the presence of N as
observed with 0.5 per cent orthophosphoric acid combined with 2 per
cent urea spray, especially in March.
- 2 and 4 per cent urea increased panicle length, number of secondarybranches
per panicle, duration of flowering, number of male and hermaphrodite
flowers, fruit set and fruit yield per panicle.
- Double superphosphate sprays also increased panicle length, duration
of flowering and number of male and hermaphrodite flowers.
- Combined spray of N and P increased length of terminal shoots and
size of leaves, advanced panicle emergence, caused a moderate increase
in flowering and fruiting characters and increased fruit yield, TSS,
reducing and non-reducing sugars, ascorbic acid and acidity.
- Similar increase in fruit quality was obtained in Langra also.
- Fruits of good size and quality by three combined sprays of 3 per
cent potassium nitrate and 0.6 per cent sodium hydrogen orthophosphate
after panicle emergence.
- A combined spray of 1 per cent urea and 1.35 per cent of muriate of
potash gave marked increase in fruit yield.
- An increase in the levels of N, P and K in the leaves with an increase
in the concentration of their sprays but the highest yield (60.5 kg
per tree) was obtained from the lowest (1 per cent) concentration.
- Foliar sprays of urea in combination with growth regulators had significant
effect on growth characters.
- Sex ratio was narrowed down by urea and growth regulator sprays.
- At pea stage, spray of 4 per cent urea and 40 ppm NAA retained maximum
number of fruits per panicle but, at later stage, 40 ppm of 2, 4-D in
combination with 4 per cent urea retained the highest number. Fruit
weight, sugars, TSS, ascorbic acid.
- TSS/acid ratio were improved and acidity was reduced.
- The maximum retention of fruits is obtained by combined spray of 6
per cent urea and 150 ppm NAA and 4 per cent urea with 120 ppm NAA.
Micronutrients
- Studies on the effect of micronutrient sprays on growth, flowering,
fruiting, yield and quality of mango are inadequate, foliar spray of
1 per cent zinc sulphate with 500 or 1000 ppm CCC significantly increased
number of panicles per shoot and fruit set and improved fruit quality.
- The improvement in fruit quality is attained by zinc sulphate spray.
- Progressive increase in the length of terminal shoot, number of leaves
and leaf area, length of floral panicle, number of male and hermaphrodite
flowers and yield with an increase in the concentration of zinc sulphate
from 0.2 to 0.8 per cent was also observed.
- Significant effect of boron on the growth, flowering, fruiting and
fruit quality of Langra by 0.8 per cent boric acid spray was observed
an increase in fruit size.
- Weight, TSS, ascorbic acid, acidity and sugar content by the spray
of boric acid and zinc sulphate.
- An increase in the status of N, P, K, Ca and Mg in leaves following
the spray of b -naphthoxy acetic acid and Ga.
- More flowering also occurred in the flowing 'off' year.
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Top
Nutritional Disorders
Potassium
Scorched leaf margins
|
Symptoms
- Scorching of leaf margins is the characteristic symptom of potassium
deficiency.
- Scorching starts from tip downwards.
- Fruit quality is reduced.
- Trees with potassium deficiency are easily prone to pests and
diseases attack.
Correction
- Application of 1 kg muriate of potash or sulphate of potash
along with 2-kg urea and 6 kg superphosphate during July-August
in the basin and incorporation could rectify potassium deficiency.
- Dropped leaves should also be incorporated along with manures
to enrich the soil health and fertility.
|
Zinc
Symptoms
Interveinal chlorosis
|
Small, narow, rosette leaves
|
- Due to zinc deficiency the leaves become small and narrow with
leaf margins bent upward or downward.
|
- Internodal length is reduced drastically and the twig with crowded
leaves gives rosette appearance.
- Pale intervenial areas and green veins are typical of zinc deficient
leaves.
- The tree with zinc hunger does not grow well and the yield, size and
quality of the fruit are reduced.
- Small plants with severe zinc deficiency may die.
- Zinc deficiency is conspicuously seen in alkaline and saline soils.
Correction
- Zinc deficiency can be rectified by spraying zinc sulphate 5 g + 10
g urea /litre water twice at 15 days interval.
Iron
Bleached mango leaves
|
Symptoms
- The leaves lose green colour and turn white and is called "Bleaching".
- The size of the leaf is reduced.
- In severe cases of iron deficiency, the leaves dry from tip
downwards.
|
- The deficiency is common in soils with high calcium content.
- Hence, the effect is known as "calcium induced iron chlorosis".
- The growth of the tree is restricted; yield and quality of the fruit
are reduced.
- Small plants may die due to acute iron deficiency.
Correction
- Two sprays at fifteen days interval with ferrous sulphate 2.5 g or
Annabedi 5 g + 1 g citric acid per litre of water effectively check
iron deficiency.
Boron
Fruit Cracking
Brown areas in Fruit pulp
|
Symptoms
- Cracking of fruit is the characteristic symptom of boron deficiency.
- Lusterless leathery leaves with thickened veins are the other
associated symptoms.
- Brown areas in yellow fruit pulp is conspicuous.
Correction
- Application of 100 g borax or boric acid per tree
incorporated with recommended dose of manures during July-August
can rectify boron deficiency.
|
Salt Injury
Scorching of leaves Tip
drying
|
Symptoms
- The leaves are scorched due to excess salt in soil or irrigation
water.
- The leaves lose their natural colour and turn to bronze colour.
- Tip burning is also seen in severe cases of salt injury.
Correction
- Raise Diancha (Sesbania) as green manure crop with onset of
monsoon in the inter-spaces of the orchard during tree bearing
years and remove Diancha plants with roots at flower bud stage
and incorporate in soil of the tree basin.
- Farm yard manure and compost should be applied adequately every
year.
- Gypsum filled gunny bag if kept in flowing irrigation water
will reduce salt effect.
|
Critical Leaf Nutrient Standards
Element
|
Kumar and Nauriyal (1977)
|
Bhargava and Chadha (1988)
|
Biswas et al., (1987)
|
N (%)
|
1.00
|
1.23
|
1.18
|
P (%)
|
0.10
|
0.06
|
0.08
|
K (%)
|
0.50
|
0.54
|
0.52
|
Ca (%)
|
1.50
|
1.71
|
-
|
Mg (%)
|
0.15
|
0.91
|
-
|
S (%)
|
0.50
|
0.12
|
-
|
Fe (m g/g)
|
-
|
171.0
|
-
|
MN (m g/g)
|
-
|
66.0
|
-
|
Zn (m g/g)
|
-
|
25.0
|
-
|
Cu (m g/g)
|
-
|
12.0
|
-
|
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Top
Flower Inducing Property of Potassium Nitrate Spray
- Mango trees are known to bear normal crops only in alternate years.
- The problem lies in the inability of once-fruited shoots to develop
flower buds once again for the next year's crop.
- The normal habit of a mango tree is that the once-fruited shoots have
to develop new fruiting wood terminally which can develop next year's
flowers and in this process one season of flowering and fruiting is
skipped over causing 'off' phase in trees leading to bienniality in
bearing.
- Potassium nitrate is one of the chemicals which has shown some potential
in promotion of flowering in off phase mango trees.
- The speciality of KNO3 is that it seem to have the capacity
for breaking dormancy in buds and especially if the bud is a differentiated
one, the flowering becomes obvious.
Mode of Action
- A sharp increase in nitrate reductase activity of mango leaves occurs
24 hours after KNO3 spraying.
- This is a normal response of many species to nitrate.
- The reduction of nitrate to ammonia (nitrate -- nitrite -- ammonia),
a fundamental biochemical process, is thought to be the first step in
the mechanism of action of KNO3.
- Ammonia is used in the nitrogen metabolism of plants to form amino
acids one of which may be Methionine.
- The Methionine could bring about mango flowering in India, although
not quite consistently so. Methionine is a precursor of ethylene has
the flower-inducing property.
- If indeed KNO3 acts via ethylene the level of this gas
should increase shortly after spraying the nitrate salt.
- Flowering is observed in shoots treated with KNO3.
- The effect of KNO3 is an inductive process, i.e., it transformed
shoots from vegetative to reproductive phase.
- Direct application of ethylene should result in faster and better
flowering than KNO3, assuming the gas is the basic causal
agent.
- Test materials should have the same initial physiological condition,
e.g., both have no preformed dormant axillary protrusions.
- No experiment of this nature has been done.
- What is known today is that the manifestation at the shoot apex of
the effect of ethylene is first noticed on the 20th day.
- With KNO3 the earliest changes took place on the fourth
day but this involved buds with axillary protrusions.
- With KNO3, the axillary protrusions enlarged and thickened
4 d after spraying.
- Floral activity was firmly established on the sixth day with the appearance
of much grown, finger-like, axillary protrusions.
- Distinct floral parts and elongated main axis can be seen on the eighth
day.
Cultivar Response
- The Philippine mangoes 'Carabao', 'Pahutan' and 'Pico' are very responsive
to KNO3 under defined or undefined physiological conditions
of trees and shoots.
- A recent addition to the list of responsive cultivars is the so-called
"Digos", inappropriately referred to in Mindanao as Carabao mango.
- 'Manila', a cultivar of the 'Carabao' race introduced to Mexico,
flowered at least 30 days ahead of the control after spraying 20 g/l
KNO3.
- 'Nam Doc Mai', a Thai mango is a foreign cultivar which allegedly
responds positively to KNO3 in its home origin (Hira 1984,
personal communication).
- Along with cvs. Luzon (not recognized in the Philippines), Florigon,
Mulgoa, Harmonams (most likely Arumanis), Neeluddin, Cambodiana (and
local?), Sabre Rouge, Sabre Blanc and Rough, 'Nam Doc Mai' has also
been reported to flower in Australia after two spraying of 40 g/l KNO3.
- Other cultivars showed a marked flowering response only after the
third spraying.
- Except Digos, all other mangoes responsive to KNO3 in the
Philippines is polyembryonic.
- No data on embryony of Digos mango is available.
- The unresponsive cultivars, on the other hand, are mostly monoembryonic.
- Whether embryony is important or not has not been established yet.
- A trial in India (Central Mango Research Stateion 1978) where mangoes
are practically all monoembryonic, was unsuccessful.
- 'Kachamitha', a cultivar of Indian origin grown in the Philippines
since 1911 has not been reported to flower with KNO3.
Species
|
Common name
|
Flowering (%)
|
Reference
|
M. indica ("Carabao")
|
mango
|
98
|
Barba (1974)
|
M. altissima
|
paho
|
70 to 100
|
Bondad et al. (1979b)
|
M. odorata
|
huani
|
100
|
Calvo (1983)
|
Comparison with other Materials
- KNO3 is the most effective salt of nitrate followed
by NaNO3 then NH4NO3.
- The least effective was Ca(NO3)2.
- Potassium nitrate was also more effective than ethephon or benzyladenine
but the latter two chemicals have synergistic effect with the former.
- The most compatible combination consisted of a mixture of the three
substances.
- Limited trials indicate that KNO3 is incompatible with
ascorbic acid.
- The latter is ineffective on 'Carabao' but promoted flowering of
mangoes in India.
- Ammonium sulfate and urea are antagonistic with KNO3.
Comparision with Smudging
- Potassium nitrate spraying results in more intense flowering than
smudging.
- Because of uniform flowering, sprayed trees become completely covered
with panicles and this is very evident at full bloom.
- Previous works on smudging reported no quantitative estimate of the
canopy area covered by flowers.
- Smudging may eventually result in a high percentage flowering but
could not completely cover the canopy with fully-opened panicles because
floral emergence is greatly protracted.
- The flowering and fruiting of 'Carabao' mango are quicker with KNO3
than smudging.
- All developmental stages of flowers and fruits are attained earlier
and their rates of growth faster with KNO3.
- Intense flowering leads to significantly smaller fruits, only about
124.3 g for KNO3 compared to 175.7 g for smudging.
Year-Round Flowering
- The period from July to February is well outside the fruiting season
and forcing trees from March to October to fruit during the former months
is of considerable practical value.
- With KNO3 'Carabao' mango can be forced to flower from
August to February.
Toxicity, Long-Term Effects and Corrective Measures
- The concentration of KNO3 required for flowering is about
10 g/l of a high grade (99%), commercially-available material.
- This is lower than that used in other fruit crops like citrus which
is sprayed with 36 g/l. potassium nitrate is also a commonly used foliar
fertilizer in the production of ornamental and vegetable crops.
- It is therefore surprising to encounter reports on leaf burning resulting
from KNO3 spraying.
- There is experimental evidence that up to 20 g/l, KNO3
does not cause leaf burning of healthy young and old 'Carabao' mango
shoots.
- A mixture of 3.0 per cent solution of potassium nitrate and 0.6 per
cent solution of sodium dihydrogen orthophosphate was found most effective
in increasing the size and quality of fruits.
- Spraying of higher concentration of these chemicals had adverse effects
on fruit quality and size.
- At the treatment combination of 5 per cent potassium nitrate and 1
per cent sodium dihydrogen orthophosphate, toxic effect on the foliage
of mango crop was observed.
- It was noted that the fruits of good size and quality can be obtained
by three sprayings of 3.0 per cent solution of potassium nitrate and
0.6 per cent solution of sodium dihydrogen orthophosphate in combination
at frequent intervals of one week on mango crop after panicle emergence.
- Application of 3 or 4 sprays, of 1 or 2 per cent of potassium nitrate
to the trees during the period of fruit bud differentiation following
the harvest of normal load of crop in 'On' year crop either alone or
in combination with certain growth regulators like TIBA or Ethrel has
resulted in promoting flowering directly on fruited shoots to the extent
of 30-40 per cent which otherwise would have been unfruitful.
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