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The effect of climatic conditions and planting dates on growth, flowering and seed production of candytuft (Iberis amara L.) under mid hill conditions of Himachal Pradesh during 2010-11 and 2011-12 were investigated. Six plantings were done at an interval of 15 days starting from September 17 in both the years with planting dates as; September 17, October 2, October 17, November 1, November 16 and December 1. The maximum plant height (34.81 cm), plant spread (33.23 cm), number of side stems/plant (6.25), earliest visible flower bud formation (55.43 days), flowering (77.80 days), duration of flowering (41.80 days), number of flower clusters/stem (15.46), number of siliquae/plant (3467.72), seed yield/plant (10.25 g) and 1 000 seed weight (2.18 g) were recorded with September 17 planting. However, earliest siliqua formation (157.58 days) was observed in December 1 planted crop.
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Indian Journal of Agricultural Sciences 87 (6): 792–5, June 2017/Article
Effect of different planting dates and climatic conditions on growth, owering
and seed production of candytuft (Iberis amara)
PRIYANKA SHARMA1, Y C GUPTA2, S R DHIMAN3, PUJA SHARMA4 and BHAVYA BHARGAVA5
Dr Y S Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh 173 230
Received: 12 August 2015; Accepted: 07 November 2016
ABSTRACT
The effect of climatic conditions and planting dates on growth, owering and seed production of candytuft (Iberis
amara L.) under mid hill conditions of Himachal Pradesh during 2010-11 and 2011-12 were investigated. Six plantings
were done at an interval of 15 days starting from September 17 in both the years with planting dates as; September
17, October 2, October 17, November 1, November 16 and December 1. The maximum plant height (34.81 cm), plant
spread (33.23 cm), number of side stems/plant (6.25), earliest visible ower bud formation (55.43 days), owering
(77.80 days), duration of owering (41.80 days), number of ower clusters/stem (15.46), number of siliquae/plant
(3467.72), seed yield/plant (10.25 g) and 1 000 seed weight (2.18 g) were recorded with September 17 planting.
However, earliest siliqua formation (157.58 days) was observed in December 1 planted crop.
Key words: Candytuft, Flowering, Iberis amara, Planting dates, Seed yield
1Research Associate (e mail: priyankafls@gmail.com),
2Professor and Head (e mail: ycgupta2006@yahoo.co.in),
3Professor (e mail: sitaramdhiman@yahoo.co.in), 4Associate
Professor (e mail: pujasharma03@gmail.com), Department of
Floriculture and Landscape Architecture, Dr Y S Parmar University
of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh
173 230, 5Scientist (e mail: bhavyabhargava01@gmail.com),
CSIR-Institute of Himalayan Bioresource Technology, Palampur,
Himachal Pradesh 176 061
Candytuft (Iberis amara L.), is a genus of owering
plant belonging to family Brassicaceae. It comprises annuals,
evergreen perennials and sub shrubs. Candytuft is a cold
hardy, fast-growing annual with lance shaped green leaves.
Pure white scented inorescence is in compact cluster shape
with numerous small dense owers. These are grown in
ower beds and also as ground covers. Seeds of appropriate
characteristics are required to meet the demand of diverse
agroclimatic conditions and intensive cropping systems.
Flower seed production seems one of the viable options
to explore with the great export potential. The climatic
conditions prevailing in North India are favourable for
cultivation of winter annuals. Farmers have already entered
into ower seed production and have reported 2.5 to 3 times
more prot than traditionally grown wheat crop in Punjab
(Chawla 2004, Singh et al. 2009). In Himachal Pradesh,
the existing climatic conditions also favour the ower seed
production. Effective pollination leading to higher seed set
depends on environmental factors, particularly temperature
and relative humidity (Gupta et al. 1995, Hall 2001) high
temperature coupled with the drying effects of low relative
humidity affect female oral structures causing reduction
in the duration of stigma receptivity, pollen germination
on the stigmatic surface, and initial pollen tube growth
(Prasad et al. 2001).
In winter annuals, the seed yield of good quality is
greatly inuenced by the planting time (Kumar and Kaur
2000). Planting dates depend upon the environmental factors
and the geographical location of the area affecting growth
and owering. There is great variation in plant growth and
owering dates due to natural environmental conditions,
therefore planting time cannot be standardised on national
scale. Environmental conditions vary from one location to
other which brings the necessity to work out the planting
time for the particular zone to get the best growth, owering
and seed yield of different annuals. Therefore, keeping in
view the importance of plant scheduling, attempts were
made to examine an applied possibility of plant scheduling
of candytuft by planting it at different dates to nd out the
optimum date of planting for ower and seed production.
MATERIALS AND METHODS
The experiment was conducted at the experimental
farm of the Department of Floriculture and Landscaping
of Dr Yashwant Singh Parmar University of Horticulture
and Forestry, Nauni, Solan (HP) during 2010-2011 and
2011-12 (altitude of 1270 m amsl and latitude of 32°51'0"
North). Open pollinated seeds of candytuft used for raising
plants were procured from the experimental farm of the
Department of Floriculture and Landscaping. Nursery raising
was done one month before transplanting. Stocky seedlings,
with four leaves were planted after basal application of
793June 2017]
85
of side stems were produced which resulted in increased
lateral growth and ultimately increase in plant spread. More
plant spread in earlier plantings has also been reported by
Kumar and Kaur (2000) in phlox, Dhatt and Kumar (2007)
in coreopsis and Dhatt and Kumar (2010) in larkspur.
Flowering parameters
Minimum number of days taken for visible bud
formation (55.43 days) and owering (77.80 days) observed
with September 17 planting which was at par with October
2 planted crop (Fig 2). Longer duration of owering (41.80
days) was observed in September 17 planted crop with
maximum number of ower clusters per stem (15.46) which
was at par with October 2 planted crop (Table 2). Earliest
visible bud formation and owering with early planting could
be attributed to the fact that plant requirement of temperature
for formation of ower buds and owering was fullled early
and plants might have attained the juvenile phase required
for ower bud formation. Comparatively higher temperature
prevailing during earlier planting dates might have resulted
in earliest ower bud formation and ultimately owering.
Earlier owering with early planting have been reported by
Kumar and Kaur (2000) in phlox, Dhatt and Kumar (2010)
in larkspur and Sharma (2012) in pansy. These ndings are
in consonance with the results of Adams et al. (1998) who
observed that rate of progress to rst owering in petunia
was hastened under high temperature and sowing later in the
season. Longer duration of owering with early plantings,
i.e. September 17 and October 2 may be attributed to climatic
conditions prevailing at the time of owering which resulted
in prolonged growth of reproductive parts, i.e. owers. These
results are in conformity with Dhatt and Kumar (2010) in
larkspur. More number of ower clusters per stem might be
farmyard manure 5 kg/m2 and fertilizers 30 g/m2 each of
nitrogen, phosphorus and potassium. Remaining half dose
of nitrogen was applied after 30 days of transplanting.
The transplanting of uniform sized seedlings was done at
a spacing of 25 cm × 25 cm from plant to plant and row
to row accommodating sixteen plants per square meter
area. Transplanting was done on six different dates from
September 17 to December 1 at an interval of 15 days during
2010 and 2011. Planting dates were six, viz. September 17,
October 2, October 17, November 1, November 16 and
December 1. The observations recorded on various growth
and owering parameters were subjected to analysis of
variance (ANOVA) randomized block design (Gomez and
Gomez 1984) keeping planting dates as treatments with
four replications. Monthly weather parameters for growing
season were taken from the meteorological observatory,
Department of Environment Science, Dr Yashwant Singh
Parmar University of Horticulture and Forestry, Nauni,
Solan (HP).
RESULTS AND DISCUSSION
Vegetative growth parameter
Planting dates signicantly inuenced the vegetative
growth of candytuft (Fig 1). September 17 planting resulted
in tallest plants (34.81 cm) with maximum spread (33.23
cm) and number of side stems per plant (6.25). Growth
parameters decreased signicantly with delay in planting
dates (Table 1). However, number of side stems were
found to be at par with October 2 planted crop. More plant
height may be attributed to the fact that plant requirement
of temperature, i.e. prevalence of warmer temperature
regime for growth was fullled which resulted in luxuriant
vegetative growth of the plants when planted in September.
Moreover, this might have resulted in more number of
nodes and elongation of nodes. Similar results of more plant
height with earlier planting have been reported by Singh et
al. (2002) in Brassica carinata and tallest plants with more
number of branches per plant by Kaur and Sidhu (2004) in
Brassica carinata. These ndings are in conformity with
the results of Blanchard and Runkle (2008), who reported
decrease in plant height of snapdragon and dianthus with
decrease in temperature. More plant spread could be
attributed to fact that during early plantings more number
EFFECTS OF PLANTING DATES ON CANDYTUFT
Table 1 Growth response of candytuft on different planting dates
Planting dates Plant height
(cm)
Plant spread
(cm)
Number of side
stems/plant
September, 17 34.81 33.23 6.25
October, 2 32.18 31.69 6.01
October, 17 31.65 29.85 5.73
November, 1 30.01 29.65 5.60
November, 16 28.85 28.34 5.43
December, 1 25.65 22.38 5.09
CD (P=0.05) 1.33 2.30 0.34
Fig 1 Effect of planting dates on plant height, plant spread and
number of side stems per plant of candytuft.
0
5
10
15
20
25
30
35
40
September, 17
October, 2
October, 17
November, 1
November, 16
December, 1
Plant height
(cm)
Plant spread
(cm)
Number of side
stems per plant
794 [Indian Journal of Agricultural Sciences 87 (6)SHARMA ET AL.
86
with November 16 planted crop (Table 3). However, the
quality and quantity of these plantings was not good enough.
September 17 planting resulted in maximum number of
siliquae per plant (3467.72), seed yield per plant (10.25 g)
and 1 000 seed weight (2.18 g) (Fig 3). 1 000 seed weight
was found to be at par with October 2 planted crop. Late
planting, i.e. December 1 and November 16 favours the
early siliqua formation. This could be attributed to warmer
temperature and low relative humidity prevailing at the time
of siliqua formation which resulted in faster maturation of
siliqua which resulted in low-grade quality and quantity of
seeds. More number of siliquae/plant obtained in September
17 planted crop may be attributed to more side stems per
plant and number of ower clusters per plant on account
of early favourable warm temperature. Moreover the high
amounts of photosynthates accumulated as a result of
increased photosynthesis ultimately resulting in increased
siliquae production. The results obtained are in conrmation
with the ndings of Singh et al. (2002) in Brassica carinata.
Maximum seed yield produced in September 17 planted crop
due to favourable environmental conditions at the time of
owering and luxuriant vegetative growth before owering
which ultimately resulted in increased photosynthesis. More
accumulation of photosynthates as a result of increased
photosynthesis might have resulted in better plant growth
and subsequently longer owering duration with maximum
number of ower clusters per stem. More number of
owers per plant in China aster when planted in August
and September as compared to other months of the year
has also been reported by Sharma et al. (2003). Further,
these results are also in line with the ndings of Kumar and
Kaur (2000) in phlox, Kumar and Kaur (2001) in coreopsis
and Sharma (2012) in pansy.
Seed yield
Earlier siliqua formation (157.58 days) was observed
in December 1 planted crop which was found to be at par
Fig 2 Effect of planting dates on owering parameters of candytuft.
0
20
40
60
80
100
120
September, 17
October, 2
October, 17
November, 1
November, 16
December, 1
Days taken for visible
bud formation
Days taken for
flowering
Duration of flowering
(days)
Number of flowers
clusters per stem
Table 2 Flowering parameters of candytuft inuenced by planting
dates
Planting dates Days
taken for
visible bud
formation
Days
taken for
owering
Duration
of
owering
(days)
Number
of owers
clusters /
stem
September, 17 55.43 77.80 41.80 15.46
October, 2 56.65 79.53 41.78 14.93
October, 17 71.28 103.08 40.73 13.55
November, 1 76.30 101.63 38.58 12.19
November, 16 73.18 98.90 36.06 10.21
December, 1 69.58 95.10 35.00 9.39
CD (P=0.05) 2.50 3.71 1.23 0.59
Fig 3 Effect of planting dates on seed yield per plant (g) and 1000
seed weight (g) of candytuft.
0
2
4
6
8
10
12
September, 17
October, 2
October, 17
November, 1
November, 16
December, 1
Seed yield per plant (g) 1000 seed weight (g)
Table 3 Effect of planting dates on seed characters of candytuft
Planting dates Days taken
for siliqua
formation
Number
of siliquae
/ plant
Seed
yield /
plant (g)
1000 seed
weight (g)
September, 17 164.85 3467.72 10.25 2.18
October, 2 164.95 3181.83 8.94 2.14
October, 17 161.83 2488.97 6.69 1.99
November, 1 161.03 1830.61 6.60 1.99
November, 16 158.13 1425.41 4.95 1.80
December, 1 157.58 1177.63 4.07 1.78
CD (P=0.05) 2.45 NS 0.66 0.10
795June 2017]
87
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on growth, owering and seed yield in Coreopsis lanceolata
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is due to the fact that early planting resulted in more number
of siliquae per plant which ultimately produced more seed
yield. Bold seeds produced in case of September 17 planted
crop might be due to favourable temperature prevailing
at the time of owering and seed maturity, and increased
pollination by pollinating agents which resulted in better seed
setting ultimately resulting in better seed lling. Moreover
the time required for seed formation after owering was
also more which resulted in better development of seeds.
More seed yield per plant, siliquae per plant and 1000 seed
weight with planting on October 10 has also been reported
by Singh et al. (2002) in Brassica carinata.
In conclusion, our results and those of previous workers
clearly indicate that early planting, i.e. September 17 and
October 2, resulted in more luxuriant vegetative growth
which ultimately resulted in better-quality owering and
seed production than late plantings. Thus, to get maximum
quality ower and seed yields in candytuft, mid September
to early October is an optimum planting time.
ACKNOWLEDGMENTS
The present research had the nancial support of Dr Y
S Parmar University of Horticulture and Forestry, Nauni,
Solan, Himachal Pradesh. The signicant contribution of
the Department of Floriculture and Landscape Architecture
researchers is acknowledged herewith. Further there is no
conict of interest either of co-authors for the content of
this manuscript.
REFERENCES
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EFFECTS OF PLANTING DATES ON CANDYTUFT
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Chawla K S. 2004. Big boost to floriculture. The Tribune, Chandigarh, India. January 15.
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Singh R, Dhaliwal H S and Joshi A S. 2009. Contract farming of floriculture in Punjab-problems and prospects. Floriculture Today 13 (11): 32-7.