Guava
Guava (Psidium guajava) is a very popular fruit. It is
available throughout the year except during the summer season. Being very
hardy, it gives an assured crop even with very little care. Its cost of
production is also low because its requirements for fertilizer, irrigation and
plant protection are not much. Further its nutritive value is very high.
Therefore it is an ideal fruit for the nutritional security. Guava is also
grown as a backyard fruit to a great extent. Best quality guavas are produced
in Uttar Pradesh, particularly in Allahabad region.
Climate
and soil
Owing to its hardy nature, guava
is grown successfully in tropical and subtropical regions up to 1,500m above
mean sea-level. Best quality guavas are obtained where low night temperatures
(10°c) prevail during winter season. It tolerates high temperatures and drought
conditions in north India in summers but it is succeptible to severe frost as
it can kill the young plants. An annual rainfall of about 100cm is sufficient
during the rainy season (July–September). The rains during harvesting period,
however, deteriorate the quality of fruits.
Guava is cultivated on varied
types of soils—heavy clay to very light sandy soils. Nevertheless, very good
quality guavas are produced in river-basins. It tolerates a soil pH of 4.5–8.2.
Maximum concentration of its feeding roots is available up to 25cm soil
depth. Thus the top soil should be quite rich to provide enough nutrients for
accelerating new growth which bears fruits.
Varieties
The varietal characteristics in
guava are not as distinct as found in majority of other fruits. Its propagation
through seeds reduces the distinctive characteristics of a variety in
commercial cultivation. Important guava varieties are:
Lucknow 49
Also known as Sardar, its fruits
are large, roundish-ovate in shape, skin primrose-yellow and pulp white, very
sweet and tasty. The TSS and vitamin C contents are high. The plants are
vigorous.
Allahabad Safeda
The most famous variety of
Allahabad, it has acquired large variations due to seed propagation. The fruits
are large in size, round in shape, skin smooth and yellowish-white. The flesh
is white, firm, soft having pleasant flavour, high TSS and vitamin C content.
The seeds are numerous, bold and hard. The trees are tall with profuse
branching and broad crown. It can withstand drought conditions.
Chittidar
This variety is very popular in
western Uttar Pradesh. The fruits are characterized by numerous red dots on the
skin, high sweetness, and small and soft seeds. It is otherwise similar to
Allahabad Safeda fruits in size, shape and pulp. It has higher TSS content than
Allahabad Safeda and Lucknow 49 but lower vitamin C content. The tree
characters resemble to those of Allahabad Safeda.
Harijha
Harijha is more popular in Bihar
because of profuse bearing. The trees are of medium vigour due to sparse
branching. The fruit is round in shape, medium large in size and
greenish-yellow in colour. Flavour is sweet with good keeping quality.
Hafshi
It is a red-fleshed guava having
good taste. It is mainly grown in Bihar. Fruit is of moderately big-size,
spherical in shape with thin skin. Trees are of medium vigour but productive.
Apple Colour
Its fruits are medium-sized and
pink-coloured. They are sweet in taste with good keeping quality. They require
temperature for the development of good pink colour. The trees are of medium
vigour but their leaves are greener than others. However, it is a
moderate-yielder.
Seedless
All the seedless
varieties—Saharanpur Seedless, Nagpur Seedless and others—are the same. Two
types of fruits, completely seedless and partly seeded, are borne on a plant of
seedless variety. The completely seedless fruits develop on the shoots rising
from the stem and these are bigger in size and irregular in shape. The partly
seeded fruits are born on normal shoots at the periphery and are small in size
and round in shape. Seedless variety is unfit for commercial cultivation
because it gives very low yield. The plants are very vigorous.
Arka Mridula
This is a seedling selection of
variety Allahabad Safeda. Its medium-sized fruits are of excellent quality with
high TSS. The white pulp has only few soft seeds. The plants are of medium
vigour but high-yielding.
Allahabad Surkha
Allahabad Surkha is an
outstanding variety of large, uniform pink fruits with deep pink flesh. The
plants produce up to 120kg fruits in its sixth year of fruiting. The fruit is
sweet, strongly flavoured with few seeds and is slightly depressed at both
ends. The plants are vigorous, dome-shaped and compact.
Guava is propagated both by
seeds and vegetatively. But vegetative propagation is commercially followed.
Seed propagation
The propagation of guava through
seeds should not be encouraged because the seedlings have long juvenile phase,
give lower yields and bear poor quality fruits. But the seedlings serve as
rootstock material for grafting or budding. The seeds should be sown as soon as
possible after extraction from the ripe fruits. Soaking of seeds in water for
12hr or in hydrochloric acid for 3 min. gives about 90% germination. About
1-year-old seedlings become ready for grafting or budding. For planting
seedling, seeds should be collected from the plants producing high-quality
fruits and high yield.
Vegetative propagation
In northern India, guava is
propagated by inarching, giving a very high percentage of success during rainy
season. But inarching is cumbersome and gives limited number of plants from the
mother plant.
Budding has been adopted only on
a limited scale in some parts of the country where the atmospheric humidity is
high. The main problem encountered in this method is disbudding of rootstock
making it labour-intensive. Among the various methods of budding—shield,
forkert, patch and chip—the patch budding is ideal giving highest percentage of
success. However, the best time of budding differs from locality-to-locality.
Layering is being commercially
followed in the southern and western India with very good results. After
bending the plant, its branches are covered with soil leaving the terminal
portion open. In a few months the rooting of branches takes place which are
then separated from the mother plants and planted in the nursery for further
sale. Layering is a labour-intensive method. A limited number of plants can
only be multiplied from a mother plant.
When mother plants are very
tall, air-layering of shoots is done during the rainy season using polythene
and moist sphagnum moss. Use of root-promoting plant growth regulator, IBA
(3,000ppm), promotes the rooting of air-layers up to 100%. The main limitation
of air-layering is the poor establishment of air layers in the nursery after
detachment from the mother plant. Further, the method is very cumbersome and
labour-intensive.
Stooling is the easiest and
cheapest method of guava propagation. The self-rooted plants (cuttings or
layers) are planted 0.5m apart in the stooling bed. These are allowed to grow
for about 3 years. Then these are cut down at the ground level in March. New
shoots emerge on the beheaded stumps. A 30cm wide ring of bark is removed from
the base of each shoot rubbing the cambium of the exposed portion in May.
All the shoots are mounded with the soil to a height of 30cm. The soil is
covered with mulch to conserve the moisture. After a period of 2 months of the
onset of monsoon, the shoots are detached from the mother plant at ringed
portion and planted in the nursery. The shoots are headed back to maintain the
root and shoot balance before planting in the nursery.
By following the technique of
ringing and mounding of the shoots, second time stooling is done on the same
mother stools in first week of September. The rooted stool layers are detached
in first week of November. Thus stooling is done twice on the same mother
stools in a year. The stooling of a mother stool can be done for many years.
With the advancement in its age, the number of stool layers also increases
every year. The growth and development of stool layers are better than
seedlings. The application of rooting hormone is not required.
A semi-dwarfing rootstock for
guava Aneuploid 82 has been developed.
Cultivation
Planting
The field for planting is
prepared during summer season by ploughing, levelling and removing weeds. The
pits of 1m × 1m × 1m size are dug and filled with a mixture of farmyard manure
and soil. If soil is good and irrigation facilities are available, the
preparation of land and digging of pits are not required. The planting is done
during the rainy season by adopting square planting system.
Guava is commercially planted at
a distance of 5–8m. The exact planting distance is, however, decided according
to variety, soil fertility and availability of irrigation facilities. Guava
Lucknow 49 needs more spacing than Apple Colour and Allahabad Safeda. Under
irrigation and high soil fertility, the plants become very vigorous requiring
more spacing. In normal conditions, a planting distance of 7m is optimum.
High-density planting reduces total soluble solids, sugars and ascorbic acid
but increases titratable acidity. The lower plant population results in the
spread of crown, while higher planting density causes erect growth of branches
making the plant tall and compact. High-density planting gives higher
yield/unit area in early years of fruiting.
Training/pruning
Traditionally, no pruning is
done in guava because the plant bears heavily even without it. But no pruning
results in the formation of narrow crotches, limb breakage due to heavy fruit
load and overcrowding. Therefore, training of plants in young stage to build
strong framework and to avoid weak crotches is necessary, whereas fruiting
trees should be pruned to check overcrowding in the orchard. The plants should
be trained as low headed trees to facilitate multiple hand pickings. The open
centre or delayed open centre system may be adopted. The scaffold branches in
young plants are to be tipped back to encourage secondary branching. The root
suckers, water sprouts and criss-cross branches are to be removed altogether.
In Maharashtra, bending of horizontal branches is practised to some extent
by tying the branches of 2 adjoining plants to increase fruiting in young
plants but it is labour-intensive and creates hindrances in cultural operations.
In every growing season, a large
number of new shoots emerge in guava a majority of which are lateral and a few
are terminal. These shoots produce fruits. After 1 year most of the lateral
shoots dry out, while terminal shoots put forth the extension growth. Hence, to
check the overcrowding and to control the plant height, the terminal shoots on
the periphery may be headed back at about 40cm level in alternate years.
Pruning also takes place during harvesting as the fruit is plucked along with
the shoot on which it is borne. Pruning is usually recommended after harvesting
or in spring. Summer pruning may damage the plant by sun burning.
Manuring and fertilization
Although guava is grown without
the application of any manure and fertilizer, it responds very well to
their application by giving higher yield and better quality fruits. For
guava-growing regions of the country, different fertilizer schedules—600g N,
400g K in northern region; 260g N, 320g P and 260g K in eastern region; 900g N,
600g P and 600g K in southern region and 600g N, 300g P and 300g K/plant/year
in western region—have been recommended. The fertilizer application should
be based on leaf nutrient status of an orchard, wherever feasible.
Time of fertilizer application
depends on the crop taken and the region. In north India, fertilizer is given
in the first week of May for rainy season crop and in first week of July for
winter season crop. In West Bengal, fertilizers are applied in 2 equal split
doses, one in January and the other in August. At Bangalore, full K and 70% N
are applied in June and full P and 30% N in September. Since 48% of feeder
roots of guava are found in the surface soil up to 25cm depth, the fertilizer should
be placed in 25cm trenches 1m away from the trunk for better uptake.
Sometimes guava suffers a
deficiency which is characterized by reduction in leaf size, interveinal
chlorosis, suppression of growth and dieback of leaders. It can be corrected by
spraying of ZnSO4 (0.45kg) and hydrated lime (0.32kg) in water (33 litres).
Bronzing is another common problem in guava. It is caused by the deficiency of
B, Zn, N, P and K due to low soil pH. The soluble P level of leaves is a better
index for bronzing. Guava Lucknow 49 is more susceptible than Allahabad Safeda.
It can be reduced by improving the soil pH and treating the soil with N, P, K
and Zn at 200, 80, 150 and 80g/year respectively, or fortnightly foliar
spraying of these nutrients each at 2% for 4 months.
Aftercare
Guava plants do not require much
care after planting. The weeds are removed by shallow cultivation. Green
manuring should be done during rainy season and clean cultivation during rest
of the year. Leguminous crops can be grown as intercrops during first 3 years
of planting to obtain more income and to increase the N content of the soil.
Both rainy and winter season
crops are very heavy compared with spring crop. Fruit quality of the winter
crop is best. Therefore, winter crop is preferred over the rainy season crop.
In northern India, normally hot and dry summers along with low soil moisture do
not allow summer flowers to set the fruits. But in mild summer and normal soil
moisture, the summer flowers set fruits for rainy season crop which is known
for its poor quality fruits and severe incidence of fruit fly and fruit-borer.
The practice of taking winter crop instead of rainy season crop is known as
crop regulation.
The rainy season crop can be
removed by spraying of urea (10%) on Allahabad Safeda and 20% on Lucknow 49 at
the time of peak flowering in summer season. Other methods of removing rainy
season crop are hand removal of flowers and fruits, spraying of bioregulators,
root exposure, withholding irrigation and pruning of ¾th of
flower-bearing shoots are either costlier or impractical or ineffective
.
Irrigation
Guava is mostly grown under
rainfed condition and irrigation is rarely practised wherever this facility is
available. However, irrigation enhances the yield of guava by making the plant
more vigorous and increasing the fruit set. Irrigation is especially desirable
after planting for survival of the plants and thereafter for 2–3 years to
obtain early good growth. Irrigation of fruiting plants depends upon the
adoption of a particular cropping pattern. For the whole year,
cropping pattern which is commercially adopted all over the country except
the northern region, irrigation is given during summer and autumn season and
for the rainy season crop, the irrigation is essential during summer season.
Normally, winter season cropping pattern is adopted in north India which
requires fortnightly irrigation during October–November. Irrigation is given to
make the soil of root zone moist; thus heavy irrigation is unnecessary. The
fruit quality of guava is adversely affected by high soil moisture content
during harvesting.
Harvesting
and Postharvest management
Guavas are harvested throughout
the year (except during May and June) in one or the other region of the
country. However, peak harvesting periods in north India are August for rainy
season crop, November–December for winter season crop and March–April for
spring season crop. In the mild climatic conditions of the other parts of the
country, the peak harvesting periods are not so distinct.
Guava fruits develop best
flavour and aroma only when they ripen on tree. In most of the commercial
varieties, the stage of fruit ripeness is indicated by the colour development
which is usually yellow. For local market, fully yellow but firm fruits are
harvested, whereas half yellow fruits should be picked for distant markets. The
fruits are harvested selectively by hand along with the stalk and leaves.
The plants begin bearing at an
early age of 2–3 years but they attain full bearing capacity at the age of 8–10
years. The yield of a plant depends on its age, cropping pattern and the
cultural practices. A 10-year-old plant yields about 100kg of fruits every
year. If both rainy and winter season crops are taken, more yield may be
obtained in the rainy season.
Ripening of guava starts on the
tree and continues even after harvest. It is accelerated in rainy season due to
high temperature and slows down in winter season due to low temperature. The
fruits are packed in baskets made from locally available plant material.
For distant markets, wooden or corrugated fibreboard boxes are used along with
good cushioning materials—paddy straw, dry grass, guava leaves or rough paper.
Good ventilation is necessary to check build up of heat. Guava is a delicate
fruit requiring careful handling during harvesting and transporting. The fruits
should reach the consumer in a firm condition.
Because of their perishable
nature, guavas are disposed off immediately after harvesting in the local
market and a very small quantity is sent to distant markets. Since fruits
are sold at a cheaper price and are available for a very long period of the
year, they are not kept in cold storage. However, shelf-life of guava can be
extended up to 20 days by keeping them at low temperature of 5°c and 75–85%
relative humidity. It can also be stored for about 10 days at room temperature (18°–23°c)
in polybags providing a ventilation of 0.25%.
Guava
wilt
Guava plants are attacked by
wilt, which alone causes heavy losses. It is very difficult to find out an
orchard of guava more than 30 years in age because most of its plants die at
about 20 years of age due to wilt. Varius fungi causing wilt are Fusarium
roseum oxysporum f. psidii, F. solani, Macrophomina phaseolina and Gliocladium
roseum. Resistant rootstock is the only solution. The
planting material should not be obtained from a wilt-infected region or
nursery.
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