Influence of Date of Transplanting on Growth and Yield Attributes and Resultant Seed Quality of Davana

A field experiment was conducted at TamilNadu agricultural university, Coimbatore during rabi 2011 to study the effect of time transplanting on growth, yield attributes and resultant seed quality of davana. The experiment was laid out with five different dates of transplanting viz., October 15, November 1, November 15, December 1 and December 15 with the spacing of 15 × 7.5 cm and 125:125:75 NPK kg/ha were adopted in a randomized block design with four replications. The results revealed that the seedlings transplanted at 15 November recorded the maximum number of branches/plant, seed yield/plant, seed yield/plot, resultant seed germination and vigour index.


Introduction
Aromatic plants are the natural source of perfumes and fragrance widely exploited by essential oil industries across the world.India stands 3 rd in essential oil production in the world.Davana (Artemisia pallens wall.ex.D.C.) is an important highly valued annual aromatic herb of India belonging to the family Asteraceae and commercially cultivated in south India as a short duration crop from November to march.India has a monopoly in production and export trade of davana oil.Davana is traditionally used in religious ceremonies and in making garlands, bouquets, floral decorations and floral chaplets, lending an element of freshness and a rich sumptuousness of fragrance to religious occasions [1] (Narayana et al., 1998).Davana is being propagated through seeds.The productivity of any crop is the ultimate results of its growth and development.Time of transplanting is one of the major factors for getting maximum seed yield and quality.Artemesia pallens possesses anti-inflammatory, antipyretic and analgesic properties.It is used in Indian folk medicine for the treatment of Diabetes mellitus [2] (Al- Harbi et al., 1994).Hence, an attempt was made to study the effect of date of transplanting on the growth and yield attributes and resultant seed quality.

Experimental Conditions
Field experiments were conducted during rabi 2011 at TamilNadu Agricultural University Coimbatore to study the effect of different dates of transplanting on the growth and yield attributes and resultant seed quality of davana.The experiment was laid out in Randomized block design with four replications.Five different dates of transplanting viz., October 15 th (DS1), November 1 st (DS2), November 15 th (DS3), December 1 st (DS4) and December 15 th (DS5) with the spacing of 15 × 7.5 cm and 125:125:75 NPK kg/ha accommodating 90 plants/ plot.The seeds of davana (Artemesia pallens) obtained from Horticultural college and Research Institute, Periyakulam was chosen for the study.Growth attributes such as plant height (cm), fresh weight of the seedling (g/plant), dry matter production, chlorophyll content of the seedling-estimated through the chlorophyllmeter at vegetative, flowering and maturity stages using SPAD meter., days to first flower, days to 50% flowering, number of branches/plant.Yield attributes viz., number of flower heads/plant, seed yield/plant, seed yield/plot, 1000 seed weight, herbage yield/plot.Resultant seed quality such as germination (%) [3] (ISTA, 1999), seedling length (cm) the distance between the tip of the primary leaf to the tip of the primary root, vigour index [4] (Ab-dul Baki and Anderson, 1873).Vigour index (VI) was computed using the following formula and expressed as whole number.VI = Germination percentage × Seedling length (cm) and Dry matter production (g•seedlings −10 ) dried in a hot air oven maintained at 85˚C for 48 h and cooled in a dessicator for 30 min and weighed in an electronic digital balance.Weather data given as Annexure 1.

Statistical Analysis
The data obtained from experiments were analyzed by the 'F' test for significance following the method Factorial Randomized Block Design as described by [5] Panse and Sukhatme.1985.Wherever necessary, the percent values were transformed to angular (Arc-sine) values before analysis.The critical differences (CD) were calculated at 5 per cent probability level.The data were tested for statistical significance.

Results and Discussion
The results of Table 1 were followed.The seedling transplanted on November 15 th (DS 3) recorded significantly higher plant height, fresh weight of the seedling, dry matter production of the seedling and chlorophyll content.Days to first flowering, days to fifty percent flowering attained earlier in the seedlings transplanted by November 15 th , number of branches/plant (26), number of flower heads/plant (110), seed yield/plant (9.01 g), seed yield/plot (112.6 g), 1000 seed weight (162.81 mg), herbage yield/plot (1268.11g) was also observed higher with the seedlings transplanted during November 15 th.Resultant seed quality such as germination%, seedling length, Dry matter production and vigour index was also higher in November 15 th seedlings which was followed by the seedlings transplanted by December 1 st .
Appropriate and proper time of sowing is one of the basic requirements for obtaining maximum yield and high return of any crop.As emphasized by [6] Snoek (1981), the total yield of the crop is markedly influenced by different sowing and transplanting times.In seed production, [7] Wood et al. (1980) opined that the environmental conditions particularly the light and temperature [8] (Crocker and Barton, 1955) interact with genetic system and elicit developmental changes during ripening, which exert influence on yield and seed quality.Highest seed yield obtained from a plant height of 58.46 cm.This was likely due to the plant height of the plots being optimum.From the observation in field plots, it could be noted that the plant could be grown in optimum condition.These contributed to more branching and flowering subsequent to seed setting and eventually resulted in high seed yield.The results of Table 2 were followed.Seedlings planted on November 15 th came to early first flowering and also 50% flowering, number of branches, number of flower heads/plant contributing towards increasing seed yield.Similarly, maximum 1000 seed weight (162.8 mg) was recorded from the plots planted on November 15 th .The results of Table 3 were followed.Highest seed yield per plant (9.01 g), seed yield/plot (112.66 g) and herbage yield per plot (1268.11g) was obtained with the seedlings planted on November 15 th and each successive delay in transplanting resulted into corresponding decrease in seed yield.Similar results were observed under different set of climatic conditions as influenced by time of planting in radish by [9] Gill and Gill (1995) and [10] Warde et al. (2004).
The seed quality characters were significantly influence by time of planting.
The physiological potential of the seed in terms of germination (64%), seedling length (2.62 cm ) and vigour index (168) were higher with the seeds produced in 15 th

Conclusion
From the present investigation, it could be concluded that the seedlings planted on 15 th November recorded the maximum seed yield and quality characters such as higher germination percentage, seedling length, drymatter production and vigour index.Hence for seed production 15 th November could be recommended for davana.

Table 3 . Influence of time of transplanting on seed yield and resultant seed quality characters.
[12]illo et al. (1994)tilloet al. (1994)and[12]Greven et al.(1997)stated that the environment during seed development is the major determinant of seed quality, particularly seed vigour.It is concluded that 15 th November planting recorded the maximum seed yield and quality characters.Hence for seed production 15 th November could be recommended for davana.