Guava physiological disorders A Lecture By Allah Dad Khan To FFS Trainee

2. Guava Physiological Disorders
A
Lecture To ToT trainees ( FFS)
By
Mr. Allah DadKhan
Provincial Coordinator IPM KPK
MINFAL Pakistan

3.  The disease infects young as well as the old
bearing trees. Some trees are more prone to
 attack. The typical symptoms include withering
of lowermost branch of the tree from top
 downwards. The growing tip turns dark brown
and necrotic areas extend backwards. A typical
 lesion develops at the junction of the diseased
and healthy areas which advances down the
 healthy areas. The infected branches defoliate
giving them a barren appearance. Application of
 1.8 kg lime or gypsum reduce the mortality of
trees by maintaining soil pH.

4. Symptoms :
 Stunted growth. Pale green
to light yellow color
(chlorosis) appearing first
on older leaves, usually
starting at the tips.
Depending on the severity
of deficiency, the chlorosis
could result in the death
and / or dropping of the
older leaves.
 Correction Measure :
 Foliar spray of Urea 1-2 %
at fortnightly intervals.


5. Symptoms :
 Slow, weak and stunted growth
with dark to blue-green
coloration to appear on older
leaves of some plants. Under
severe deficiency, purpling in
leaves and stems may appear.
Delayed maturity and poor seed
and fruit development.
 Correction Measure :
 Foliar spray of DAP 2% at
fortnightly interval.




6. Symptoms :
 Chlorosis along the edges of
leaves (leaf margin scorching)
occurs first in older leaves.
Plants lacking K will have slow
and stunted growth. Stems are
weak. The size of seeds and
fruits and the quantity of their
production is reduced
 Correction Measure :
 Foliar spray of K2SO4 2% at
fortnightly interval.


7. Symptoms :
 Symptoms first appear on the
younger leaves and leaf tips.
The growing tips of roots and
leaves turn brown and die.
Newly emerging leaves may
stick together at the margins,
which causes tearing as the
leaves expand and unfurl.
Younger leaves may be
cupped and crinkled, with
the terminal bud
deteriorating.
 Correction Measure :Soil
application of gypsum @ 20
kg /
 ha.

8. Symptoms :
 The deficiency symptom of
interveinal chlorosis first
appears in older leaves. Leaf
tissue between the veins may be
yellowish, bronze or reddish,
while the leaf veins remain
green. In severe cases,
symptoms may appear on
younger leaves and cause
premature leaf drop. Symptoms
occur most frequently in acid
soils and soils receiving high
amounts of K fertilizer or Ca.
 Correction Measure :
 Foliar spray of MgSO4 2% at
fortnightly interval.

9. Symptoms :
 Younger leaves are chlorotic
with evenly, lightly colored
veins. Growth rate is retarded
and maturity is delayed. Plant
stems are stiff, thin and
woody. Symptoms may be
similar to N deficiency and
are most often found in
sandy soils that are low in
organic matter and receive
moderate to heavy rainfall.
 Corrective Measure :Soil
application of gypsum @ 20
kg /ha.


10. Symptoms :
 Stunted growth, first
showing symptoms on
the growing point and
younger leaves. The
leaves tend to be
thickened and may curl
and become brittle.
 Correction Measure:
 Foliar spray of Borax
0.5% at fortnightly
interval.



11. Symptoms :
 Interveinal chlorosis in
younger leaves. The
youngest leaves
become pale yellow.
 Corrective Measure :
 Soil application of
FeSO4 @ 10 kg/ha.


12. Symptoms :
 Symptoms first appear
as chlorosis in young
tissues. Unlike Fe
chlorosis symptoms,
Mn chlorosis shows up
as tiny yellow spots.
 Corrective Measure :
 Foliar spray of MnSO4
1% at fortnightly
interval.
