Research work on African marigold
For:
- Cultivation practice of African marigold.
- Flower and petal yield.
(1). Research work on Tagetes erecta
Also read: Xanthophyll in marigold M. Sc. Thesis
1.1: Location of experimental site
The experimental site was located at the Horticultural Research
Instructional Farm of the Department of Horticulture, College of Agriculture, Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh where adequate
facilities for irrigation and drainage existed.
1.2: Geographical situation
Raipur, the place of investigation, is situated in the central part of
Chhattisgarh at 21°16° N latitude, 81°36° E longitude and at an altitude of 286.56m from mean sea level.
1.3: Agro-climatic condition
Raipur is located in dry sub humid agro-climatic region. The annual rainfall of the region ranges from 1200-1325 mm, which is received from third week of June to first week of September and very little during October and February.
The pattern of rainfall, particularly during June to September months has great variation from year to year. The maximum temperature of this region may reach as high as 46 °C during summer and minimum may fall to 6 °C during winter.
The atmospheric humidity is high from June to October. Weekly average meteorological data during the span of experimentation June 2014 to December 2014 as recorded at Meteorological Observatory, IGKV, Raipur.
1.4: Soil characteristics of the experimental field
The soil of the experimental field was silt-loam. The soil samples (upto a depth of 20 cm) were collected randomly from five different places of the experimental site before layout of experiment.
(2). Cultural operations
2.1: Field preparation
Field preparation was done by ploughing the field with mould board plough once, followed by leveling and weeding manually. Harrowing was done to breakthe clods followed by criss-cross ploughing by cultivator, then the field was
pulverized by rotavator.
During harrowing, well rotten FYM was incorporated in the soil. The experiment was laid out with the help of measuring tape, rope and bamboo pegs. The small-sized beds were prepared.
2.2: Raising of seedlings
Marigold seeds were sown on raised beds. Line sowing of seeds were done at 5 cm spacing. The seed beds were covered with a mixture of garden soil and coarse sand. The nursery beds were covered by the paddy straw after sowing.
Initially, watering was done with watering can at alternate days.
The sowing was done on 18th June. The seeds were germinated within 3-4 days of sowing and thereafter mulch cover was removed. The seedlings were hardened by withdrawing the watering 2-3 days before lifting the seedlings.
2.3: Transplanting and gap filling of seedlings
Marigold seedlings were transplanted after 27 days of sowing. Light irrigation was given just after planting with the help of hazara (rose can). Marigold seedlings are generally soft, tender and susceptible to damping off. Hence, gap filling was done after two weeks of transplanting in case of mortality.
2.4: Manures and fertilizers
Well decomposed FYM @ 20 tonnes ha-1 was applied at the time of land preparation. The recommended dose of 200:200:200 kg per ha. NPK was applied in two splits i.e. 50 per cent ‘N’ and full dose of P and K at the time of transplanting and remaining 50 per cent ‘N’ was applied 40 DAT in the form of urea.
2.5: Irrigation and weeding
Four irrigations were applied during entire crop season. Soil was kept moist after monsoon and heavy irrigation was avoided to check moisture stress.
Manual weeding (4 times): During the entire cropping period at an interval of 15-20 days.
2.6: Pinching
Pinching by removal of the terminal portion or new growth of the plants
was done in 30 days after transplanting.
(3). Observations on vegetative phase
3.1: Plant height (cm)
The plant height of five randomly selected plants from each plot was
measured from the ground level to the tip of the plant with the help of meter scale. The average height was calculated by dividing the summation with five.
3.2: Plant spread (cm)
The plant spread was measured in the five tagged plants with the help of meter scale in the North-South and East-West direction. The average value was then worked out.
3.3: Number of primary branches per plant
Number of primary branches per plant of the five randomly selected plants from each plot was counted at bud stage and the average was then calculated by dividing the summation with five.
3.4: Number of secondary branches per plant
Number of secondary branches per plant of the five randomly selected plants from each plot was counted at bud stage and the average was then calculated by dividing the summation with five.
(4). Observations on flowering attributes
4.1: Days to 50 per cent flowering
When 50 per cent of the plants came into flowering, this observation was taken with reference to the date of planting.
4.2: Number of flowers per plant
The total number of flowers per plant was counted in each plot from the five tagged plants at the flowering stage and then averaged to get the value.
4.3: Flower diameter (cm)
The maximum diameter of five flowers from the tagged plants per plot at fully open stage was recorded and then averaged for arriving at the flower size. The flower diameter was measured with the help of meter scale.
4.4: Weight of flowers per plant (g)
Fully mature five flowers were randomly selected per tagged plant and weighed after each picking till all the flowers were harvested. Their mean weight was calculated as average fresh weight of flowers per plant.
4.5: Dry weight of flowers per plant (g)
After oven drying the fresh flowers, dry weight was determined with the
help of electronic balance.
4.6: Duration of flowering (days)
Number of days taken from the first flowering to the last flowering per plant was recorded as total duration of flowering for each treatment.
4.7: Flower yield (kg per plot)
Flower yield per plot was calculated from the flower weight per plant of the tagged plants for all the treatments in all replications and then averaged.
4.8: Flower yield (t per ha)
It was calculated by multiplying total number of plants and flower yield
per plant for each plot and then worked out per unit area (t per ha.).
4.9: Duration of flowering (days)
The treatment T6 recorded longest duration of flowering (94.36 days)
followed by T7, T14, T11 and T13 (93.29, 93.12, 92.33 and 90.50 days, respectively) all at par with each other but significantly superior over standard check. The minimum duration of flowering was observed in T10 (54.74 days).
The genetic control of the characters and modification in their expression
due to environmental conditions might be the possible cause of observed variation in duration of flowering. Panwar et al. (2013) reported a general high range for
duration of flowering in African marigold.
4.10: Dry weight of flowers per plant
The dry weight of flowers per plant
differed significantly due to different
genotypes.
The treatment T6 recorded maximum flower dry weight (75.91g) per plant followed by T11 (73.94 gm). Both the treatments were at par but significantly superior to other treatments. The minimum dry weight was recorded in the treatment T10 (25.05 gm).
The difference in dry weight of flower might be due to inherent characters
of the individual genotypes and also affected by flower weight and diameter (Singh and Singh, 2006).
4.11: Flower yield (kg per plot)
The maximum flower yield per plot
(3.74 kg) was recorded in T11 followed by T6 (3.71 kg), which were having at par values but significantly superior over standard check (T15) with 2.62 kg per plot. While it was observed to be lowest in T10
(0.73 kg).
Data recorded on flower yield per plot might have varied due to inherentcapacity of genotypes to yield flowers (Raghuwansi and Sharma, 2011). Similar result was also revealed by Behera et al. (2002) in chrysanthemum.
4.12: Flower yield (t per ha.)
Different genotypes demonstrated significant differences on flower yield per ha.
The maximum flower yield (26.14 t per ha) was recorded in T11 which was followed by T6 (25.87 t per ha) both having at par values with respect to flower yield but significantly superior to all other treatments. The standard check variety recorded 18.19 t per ha whereas, minimum flower yield was obtained in the treatment T10 (5.15 t per ha).
The increase in flower yield per ha may be due to increased flower weight and number of flowers per plant of specific genotypes. Variation in flower yield of varieties was also observed in China aster by Negi and Raghava (1985) and by (Howe and Waters, 1991) in marigold.