I feel happy to share my poster on the topic Effect of pre-harvest treatments on post harvest bulb rotting, sprouting and physiological loss in weight of onion var. Arka Kalyan

1. Effect of pre-harvest treatments on post harvest bulb rotting, sprouting and physiological loss in weight of onion
var. Arka Kalyan
Ayeeshya H K,1
Jagadeesh S L1
, Prasanna S M1
, Vijaymahantesh2
, Mahesh Y S2
and Hadimani H P3
1
College of Horticulture, Bagalkot, 3
KRC College of Horticulture, Arabhavi
2
Directorate of Extension, University of Horticultural Sciences, Bagalkot-587104, Karnataka
Onion (Allium cepa L.) known as queen of kitchen is an important commercial vegetable crop
of India with many medicinal use and export demand. It is a seasonal crop. In order to meet out
the requirements in offseason, export demand and to check glut during excess production, storage
assumes paramount importance.
Onion is a delicate to store because of higher water content and serious losses occur due to
rotting, sprouting, physiological loss in weight and moisture evaporation. In general, the losses
due to physiological loss in weight, sprouting and rotting (decay) were found to be 30 to 40 per
cent, 20 to 40 per cent and 20 to 30 per cent respectively.
Plant growth regulator and fungicides could be employed as pre-harvest foliar spray to extend
the shelf life and reduce spoilage in onion. These chemicals are thought to be beneficial to
maintain the quality of onion bulbs in storage with respect to reduction of physiological loss in
weight, rotting and sprouting when applied as pre-harvest sprays and as a seedling dip. In view of
these aspects, the present study was conducted to investigate the efficacy of salicylic acid,
azoxystrobin and CCC on physiological loss in weight, rotting and sprouting in onion cv. Arka
Kalyan during storage.
Onion (Allium cepa L.) known as queen of kitchen is an important commercial vegetable crop
of India with many medicinal use and export demand. It is a seasonal crop. In order to meet out
the requirements in offseason, export demand and to check glut during excess production, storage
assumes paramount importance.
Onion is a delicate to store because of higher water content and serious losses occur due to
rotting, sprouting, physiological loss in weight and moisture evaporation. In general, the losses
due to physiological loss in weight, sprouting and rotting (decay) were found to be 30 to 40 per
cent, 20 to 40 per cent and 20 to 30 per cent respectively.
Plant growth regulator and fungicides could be employed as pre-harvest foliar spray to extend
the shelf life and reduce spoilage in onion. These chemicals are thought to be beneficial to
maintain the quality of onion bulbs in storage with respect to reduction of physiological loss in
weight, rotting and sprouting when applied as pre-harvest sprays and as a seedling dip. In view of
these aspects, the present study was conducted to investigate the efficacy of salicylic acid,
azoxystrobin and CCC on physiological loss in weight, rotting and sprouting in onion cv. Arka
Kalyan during storage.
Seedlings of cv. Arka Kalyan were raised on raised nursery bed of size 1.8m × 1.8m. Healthy
seedlings were transplanted to main field at a spacing of 10 cm x 15 cm.
The cultural practices and plant protection measures were followed as per the recommended
package of practices.
The experiment was laid out in randomized completely block design with 3 replications and 12
treatments.
Treatment details
T1 - Control
T2 - Pre-harvest spray of salicylic acid (SA) (2 mM) at 60 + 90 DAT
T3 - Seedling dip in SA (2 mM) + Pre-harvest spray of SA (2 mM) at 60 + 90 DAT
T4 - Pre-harvest spray of azoxystrobin (0.1%) at 60 + 90 DAT
T5 - Pre-harvest spray of SA (2 mM) and azoxystrobin (0.1%) at 60 + 90 DAT
T6 - Seedling dip in SA (2 mM) + Pre-harvest spray of SA (2 mM) followed by foliar spray of
azoxystrobin (0.1%) at 60 + 90 DAT
T7 - Pre-harvest spray of CCC 2500 ppm at 90 DAT
T8 - Pre-harvest spray of SA (2 mM) at 60 + 90 DAT and foliar spray of CCC 2500 ppm at
90 DAT
T9 - Seedling dip in SA (2 mM) + Pre-harvest spray of SA (2 mM) at 60 + 90 DAT and foliar
spray
CCC (2500 ppm) at 90 DAT
T10 - Pre-harvest spray of azoxystrobin (0.1%) at 60 + 90 DAT and foliar spray of CCC (2500
ppm) at 90 DAT
T11 - Pre-harvest spray of SA (2 mM) and azoxystrobin (0.1%) at 60 + 90 DAT followed by CCC
(2500 ppm) foliar spray at 90 DAT
T12- Seedling dip in SA (2 mM + Pre-harvest spray of SA (2 mM) and azoxystrobin (0.1%) at
60+90 DAT followed by foliar spray of CCC (2500 ppm) at 90 DAT
OBSERVATIONS:
1. Physiological loss in weight: In each replication, 25 bulbs were earmarked to record the PLW.
The marked bulbs of the respective treatment were weighed individually at the beginning of storage
to record the initial weight. Subsequently at monthly interval the bulbs were weighed again. The
cumulative losses in weight of bulbs were calculated and expressed as per cent
Physiological loss in weight (%) = P0 – P1 or P2 or P3 or P4 x 100
P0
P0 Initial weight of the bulb, P1 Weight of the bulb after 1 month
2.Rotting per cent: It was determined by dividing weight of rotten bulbs from initial weight of
bulbs. The value was expressed in percentage.
Rotting (%) = Weight of the rotted bulbs x 100
Initial weight of bulbs
3. Sprouting per cent: It was determined by dividing weight of sprouted bulbs from initial weight
of bulbs. The value was expressed in percentage.
Sprouting(%) = Weight of the sprouted bulbs x 100
Initial weight of bulbs
Seedlings of cv. Arka Kalyan were raised on raised nursery bed of size 1.8m × 1.8m. Healthy
seedlings were transplanted to main field at a spacing of 10 cm x 15 cm.
The cultural practices and plant protection measures were followed as per the recommended
package of practices.
The experiment was laid out in randomized completely block design with 3 replications and 12
treatments.
Treatment details
T1 - Control
T2 - Pre-harvest spray of salicylic acid (SA) (2 mM) at 60 + 90 DAT
T3 - Seedling dip in SA (2 mM) + Pre-harvest spray of SA (2 mM) at 60 + 90 DAT
T4 - Pre-harvest spray of azoxystrobin (0.1%) at 60 + 90 DAT
T5 - Pre-harvest spray of SA (2 mM) and azoxystrobin (0.1%) at 60 + 90 DAT
T6 - Seedling dip in SA (2 mM) + Pre-harvest spray of SA (2 mM) followed by foliar spray of
azoxystrobin (0.1%) at 60 + 90 DAT
T7 - Pre-harvest spray of CCC 2500 ppm at 90 DAT
T8 - Pre-harvest spray of SA (2 mM) at 60 + 90 DAT and foliar spray of CCC 2500 ppm at
90 DAT
T9 - Seedling dip in SA (2 mM) + Pre-harvest spray of SA (2 mM) at 60 + 90 DAT and foliar
spray
CCC (2500 ppm) at 90 DAT
T10 -Pre-harvest spray of azoxystrobin (0.1%) at 60 + 90 DAT and foliar spray of CCC (2500
ppm) at 90 DAT
T11 - Pre-harvest spray of SA (2 mM) and azoxystrobin (0.1%) at 60 + 90 DAT followed by CCC
(2500 ppm) foliar spray at 90 DAT
T12- Seedling dip in SA (2 mM + Pre-harvest spray of SA (2 mM) and azoxystrobin (0.1%) at
60+90 DAT followed by foliar spray of CCC (2500 ppm) at 90 DAT
OBSERVATIONS:
1. Physiological loss in weight: In each replication, 25 bulbs were earmarked to record the PLW.
The marked bulbs of the respective treatment were weighed individually at the beginning of storage
to record the initial weight. Subsequently at monthly interval the bulbs were weighed again. The
cumulative losses in weight of bulbs were calculated and expressed as per cent
Physiological loss in weight (%) = P0 – P1 or P2 or P3 or P4 x 100
P0
P0 Initial weight of the bulb, P1 Weight of the bulb after 1 month
2.Rotting per cent: It was determined by dividing weight of rotten bulbs from initial weight of
bulbs. The value was expressed in percentage.
Rotting (%) = Weight of the rotted bulbs x 100
Initial weight of bulbs
3. Sprouting per cent: It was determined by dividing weight of sprouted bulbs from initial weight
of bulbs. The value was expressed in percentage.
Sprouting(%) = Weight of the sprouted bulbs x 100
Initial weight of bulbs
IntroductionIntroductionIntroductionIntroduction
Material and MethodsMaterial and MethodsMaterial and MethodsMaterial and Methods
ConclusionsConclusions
ReferencesReferences
Fig. 2: Graph showing effect of field application of SA, azoxystrobin and CCC on marketable bulbs
and rotting (a) and sprouting (b) in onions during storage .
Fig. 1: Graph showing effect of field
application of SA, azoxystrobin and
CCC on marketable bulbs and PLW
in onions during storage
In the present investigation reduced PLW was showed by the bulbs which are sprayed
with SA @ 2mM, azoxystrobin @ 0.1% at 60+90 DAT and CCC @ 2500 ppm at 90
DAT. It may be due to combined effect of SA, CCC and azoxystrobin. The elicitor SA
known to reduce respiration, transpiration rate of the bulbs and also rate of moisture loss
thus prevented the loss in weight (Singh and Dhankhar ,1995).
The combined application of azoxystrobin (0.1%) and SA (2 mM) at 60 & 90 DAT resulted
in reduced rotting which is followed by T11. It is because of azoxystrobin a broad spectrum
fungicide with protectant, curative, eradicant and systemic properties. Which shows wide
range of disease control and activity against Oomycetes, Ascomycetes, Basidiomycetes and
Deuteromycetes. Inhibition of mitochondrial respiration is an important mode of action for
inhibiting pathogen growth. It has the ability to inhibit electron transfer in fungal
mitochondria by binding at a specific site on cytochrome b. The result of this activity is the
cessation of normal energy production (ATP) within the cells, which results in cell death.
Whereas exogenous application of SA could enhance resistance to pathogens and control
post-harvest decay (Asghari et al., 2009). It also exhibits direct antifungal effects against
pathogens. The growth retardant cycocel is also known to decrease per cent rotting in onion
with cycocel (lihocin) @ 2500 ppm on 75 and 90 days after transplanting (Anonymous,
2004).
Bulbs harvested by dipping the seedling in the SA @ 2 mM followed by foliar spray of SA
@ 2 mM, azoxystrobin @ 0.1% and CCC 2500 ppm at 90 DAT exhibited least per cent
sprouting which is followed by treatment T11. The combined application of chemical was
found to be effective in sprout suppression. It indicates the existence synergy among the
chemicals and each chemical contributes its own share for sprout suppression. The Growth
regulator CCC prolongs the dormancy for longer period after harvest. Which is attributed to
reduced neck thickness in sprayed bulbs and by way of minimised cell division and due to
the removal of apical dominance inhibiting sprout initiation. The results of the present
investigation are in conformity with the findings of Anbukkarasai et al.(2013). The
Fungicide azoxystrobin is known to influence certain aspects of plant physiology, likely
through the interaction with electron transfer in plant mitochondria. The strobulin shifted
the hormonal balance, favouring cytokinin as opposed to ethylene, and causing up to a two
fold increase in endogenous level of abscisic acid (ABA) a harmone which checks the
growth. The phytoharmone ABA plays an important role in many physiological process in
plants. This harmone is necessary for regulation of several events during late seed
development and is crucial for the response to environmental stresses (Anatonio et al.,
2012). SA treated plants accumulated high concentration of ABA (Sakhabutdinova et al.,
2003).
Combined application of SA(2 mM), azoxystrobin 0.1% at 60+90 DAT and CCC 2500
ppm at 90 DAT was found to be effective in reducing PLW, rotting and sprouting in
onion
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Int. Postharvest Sym. Antalya, Turkey, pp. 8-12.
Sakhabutdinova, A. R., Fatkhutdinova, D. R., Bezrukova, M. V., and Shakirova, F. M., 2003, Salicylic
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