Effect of Spacing and Sowing Time on Growth and Yield of Carrot (Daucus carrota L.)

Transcription

1 International Journal of Sustainable Agriculture 5 (): 9-6, ISSN 79-7 IDOSI Publications, DOI:.589/idosi.ijsa Effect of Spacing and Sowing Time on Growth and Yield of Carrot (Daucus a L.) Ashraful Kabir, Arfan Ali, M.H. Waliullah, 5 Mehdee Mohay Men-Ur Rahman and Abdur Rashid Office of the Controller of Examinations, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh Department of Horticulture, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh Fruit Research Station, BARI, Rajshahi, Bangladesh Department of Biochemistry, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh 5 Department of Agribusiness and Marketing, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh Abstract: An investigation was carried out at the Horticulture Farm of Sher-e-Bangla Agricultural University, Dhaka during the period from November 5 to April 6 to determine the growth and yield of as influenced by different sowing dates and spacing. The study was conducted with four sowing times of viz. 8 November (T ), 8 (T ), 8 (T ) and 8 (T ) having three spacings viz. cm x cm (S ), 5cm x 5cm (S ) and cm x cm (S ). Leaf length, root length, leaf fresh weight, root fresh weight, root diameter, leaf dry weight and root dry weight were significantly differed among the sowing times at different spacings. The maximum root length (.8 cm), root diameter (.9 cm), root fresh weight (7. g plant ) and root dry weight (.7 g plant ) were found in Tand the minimum of these parameters were found in TS. The percentage of cracking root and branched root of was lower in Tfollowed to others and it was gradually increased due to delay sowing. Key words: Carrot Growth Root length Root weight Dry matter INTRODUCTION its requirement. It contains high amount of carotene ( mg/ g), thiamin (. mg/ g), riboflavin Carrot is mainly a temperate crop grown during spring (.5 mg/ g) and also serves as a source of through autumn in temperate countries and during winter carbohydrate, protein, fat, minerals, vitamin-c and in tropical and subtropical countries of the world []. calories [5]. Sugar and volatile terpenoids are the two According to Barnes [], 5.6 C to. C temperature is major components of flavor; glucose, fructose the ideal for its growth and development. Higher and and sucrose which make up more than 95% of the lower temperatures reduce the rate of growth and free sugars and % to 6% of the stored adversely affect the quality of the roots. Carrot grows carbohydrates in the root. The ratio of sucrose successfully in Bangladesh during Rabi season when to reducing sugar increases with root maturity temperature ranges from.7 C to 8.9 C [] and the best but decreases following harvest and during cold time is from mid November to early for its storage [6]. Blindness in children for the severe cultivation to get satisfactory yield []. Vitamin-A deficiency is a problem of public health in Vegetables are one of the most important some countries, particularly in the rice dependent components of human food, which provides proteins, countries of Asia [7]. So, (rich in Vitamin-A) may carbohydrates, fats, vitamins and minerals. Per capita contribute a lot of Vitamin-A to overcome this situation in vegetable production in Bangladesh is much less than Bangladesh, Corresponding Author: Ashraful Kabir, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh 9

2 Intl. J. Sustain. Agric., 5 (): 9-6, Plant spacing is one of the important factors for the Factor A: Sowing time: Carrot seeds were sown at four increased production of. Pavlek [8]; Lipari and different times denoted as T, McCollum et al. [] reported that there is a positive correlation between the number of plants and yield of T, T and T :. But many workers reported that different plant T = st sowing, November 8, 5 densities of spacing have different effect for the T = nd sowing, 8, 5 marketable yield of [, ]. T = rd sowing, 8, 5 Sowing time is also an important factor for increasing T = th sowing, 8, 5 yield of []. The different sowing time of have a significant effect on growth and yield due to Factor B: Spacing: Three different spacing were used environmental factor like temperature and light intensity denoted as S, S and [] suggested that should be harvested at proper stage of maturity. Otherwise, it will become fluffy and S = cm cm unfit for consumption. Moreover, the percent of root S = 5 cm 5 cm splitting, firmness, the contents of dry matter, carotene S = cm cm and sucrose are increased during the growth of, whereas the contents of glucose and fructose and The two factors experiment was laid out in a RCB respiration quotient are decreased. The contents of total Design with three replications. The whole experimental sugar remained almost constant from the beginning of the area was.5m 8.m, which was divided into three harvesting period but increased at low temperature. blocks. Each block was again divided into plots and To extend the availability of during the early hence there were 6 ( ) unit plots. The treatments were and late period of growing season and sowing time may assigned randomly in each block separately. The size of play a critical role. Also quality of the roots depends on unit plot was.m.5m. The distance between two the harvesting time under Bangladesh condition. There is adjacent blocks and plots were. m and.5 m also a significant interaction between plant spacing and respectively. Land preparation, manuring and intercultural sowing date [5]. Therefore, the present investigation was operations were done properly. taken find out optimum sowing time and spacing for better Growth parameters were recorded at 5 days growth of. interval after days of sowing and continued to harvest. Ten plants in each plot were used to count number of MATERIALS AND METHODS leaves per plant. Percentage of dry matter was calculated as follows. The experiment was conducted at the Horticulture Farm of the Sher-e-Bangla Agricultural University, Dhaka Fresh weight of root (g) Percentage of dry matter = during November 5 to April 6. Laboratory works Dry weight of root (g) were done both at Horticulture Laboratory and Soil Science Laboratory in Sher-e-Bangla Agricultural The recorded data on different growth and yield University, Dhaka-7. The experiment area was parameters were calculated for statistical analysis. belonged to the Modhupur Tract and AEZ 8 Analyses of variances (ANOVA) for most of the (FAO, 97). The soil was sandy loam with a phvalue 6.6. characters under consideration were performed with the Soil samples were collected randomly from a depth up to help of MSTAT program. Treatment s were cm of the experimental plot and analyses were done separated by Duncane's Multiple Range Test (DMRT) at and showed nitrogen.75%, phosphorus ppm, 5% level of significance for interpretation of the results. exchangeable potassium. me/g soil and organic carbon.8%. RESULTS AND DISCUSSION New Caroda, variety of, was used for the experiment. The seeds of this variety were collected Plant Height: Four different sowing times were from "Hamid Seed Store", Siddique Bazar, Dhaka. statistically significant in respect of plant height of The experiment was conducted to study the effect of four (Fig. ). It varied from 5. cm to 6.8 cm. The maximum levels of sowing times and three levels of spacing. plant height (5. cm) was observed from the plants Different levels of two factors were as follows: planted on 8 November (T ) while the minimum (6.8 cm)

3 Intl. J. Sustain. Agric., 5 (): 9-6, Plant height (cm) Plant Height (cm) T T T T.76 Sowing time. Spacing Fig. : Effect of sowing times on plant height (cm) of Fig. : Effect of spacing on plant height (cm) of on 8 (T). The result under the treatment T predicted that early sowing performed longer plant height compared to late sowing (T ) (Fig. ). There were optimum environmental conditions for grown on late November among the other three sowing dates. All environment factors especially temperature supported for vegetative growth simultaneously. The plant height was varied significantly due to the variation of spacing (Fig. ). It ranged from 8.9 cm to.76 cm. The tallest plant was observed from the spacing of cm x cm (S ) while the shortest from the spacing of cm x cm (S ). The plants under the treatment of S (cm x cm) had enough space for vegetative growth and had less nutritions competition compared to other plants sown under the treatment S (cm x cm) and S (5cm x 5cm). The findings were not agreed with Amjad and Anjum [6] due to different environmental conditions between Bangladesh and Pakistan. A significant interaction was found between sowing times and spacing on plant height (Table ). The plant height varied from. cm to 6.65 cm. The tallest plant (6.65 cm) was observed from the treatment of TS followed by others. The shortest plant (. cm) was recorded from the treatment of T S. T T T T Table : Effect of sowing time and spacing on leaves per plant of Leaves per plant - Spacing T T T T.7bc.cd 8.6de 6.e 9.b 5.7ab. bc.6cd 8.7de.75ab 8.9a 5.6ab.9bc.69cd.6a Sowing dates 5.8a.ab.7bc 8.8c.87 T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm Number of Leaves per Plant: A significant variation was observed on leaves per plant in four sowing times (Table ). It ranged from 8. to 5.8. The highest (5.8) number of leaf per plant was obtained from the plants grown at 8 November which was significantly differed from all other treatments except T (8 ). The lowest number of leaves (8.) per plant was obtained from plants grown on 8 (T ) which was statistically similar to the plants grown on 8 (T ). Results revealed that there was an increasing tendency in number of leaves per plant grown on 8 November (T ) than 8 (T ) and decreasing up to 8 (T ) from 8 (T ). The present results agreed with the results obtained by Bussell and Dallenger [7]. Leaves per plant were found significant due to different spacing. The leaf number of different spacing varied from 9. to.6 (Table ). The maximum number of leaves (.6) was found at cm cm spacing (S ) and the minimum (9.) was found at cm cm spacing (S ) because plants at cm cm spacing could uptake more nutrients than other plants due to higher spacing. After words in treatment cm cm, the number of leaves increased but decreased in other treatment due to senescence. The variation of leaves number per plant as affected by time of sowing might be to the variation in the environmental conditions during growing period. The interaction effect of sowing time and spacing showed significant variation on leaves per plant (Table ). The number of leaves per plant varied from 6. to 8.9. The highest (8.9) number of leaves was recorded from the treatment T S that was statistically similar to those of T S and T S The lowest (6.) number. of leaves was found from T S that was statistically similar to those of T S and T S. Weight of Fresh Leaves: Weight of fresh leaves under study varied significantly due to four different sowing times (Table ). The weight of fresh leaves varied from

4 Intl. J. Sustain. Agric., 5 (): 9-6, Table : Effects of sowing time and spacing on weight of fresh leaves (g) of Weight of fresh leaves (g) Spacing T T T T 9.8de 7.ef 5.96fg.58g 6.c.b.cd 8.6de 5.98g 88.7b 5.7a.5b.7bc 7.96ef 5.7a Sowing dates.5a.b 8.c 5.7d 89.7 differed at 5% level by DMRT T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm Table : Effects of sowing time and spacing on weight of dry leaves of Weight of dry leaves (g) Spacing T T T T S 9.5bc.6cd 7.9de.f.6b.5ab 9.bc.9de.9ef.6ab 8.97a.76ab.cd 6.6ef 7.7a Sowing dates.a 8.5a.78b.9c. T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm Table : Effects of sowing time and spacing on length of root (cm) of Length of root (cm) Spacing T T T T.cd.9de 6.97fg 6.g 8.58b.9b.66bc 8.ef 6.9fg 9.99ab.8a.bc 9.9de 7.fg.a Sowing dates.a.6a 8.5b 6.69b 9.86 T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm 5.7g to.5g. The maximum leaf fresh weight (.5g) was obtained from the plants when grown on 8 November (T ), which was statistically dissimilar to the plants grown on 8 (T ). The minimum fresh weight of leaves (5.7g) was observed when grown on 8 (T ). Results revealed that the weight of fresh leaf gradually decreased from T to T. The present results were supported by Bussell and Dallenger [7]. Significant variation was found in respect of weight of fresh leaves by different spacing. The weight of fresh leaf varied from 5.7g to 6.g (Table ). The maximum weight (5.7g)was found to the plants were grown at the spacing of cm cm (S ) while the minimum (6.g) in cm cm (S ). The weight of fresh leaf was gradually decreased from the plants grown from spacing S (cm cm) to S (cm cm) The interaction effect of sowing time and spacing was statistically significant in respect of weight of fresh leaf (Table ). The weight of fresh leaf ranged from.58g to 5.7g. The maximum fresh weight was recorded from the plants grown at the spacing of cm cm and planted at 8 November (TS ) while the minimum (.58g) at the spacing of cm cm and grown on 8 (TS ) which was statistically similar to that of Tand TS. The highest weight of fresh leaf was statistically different from the other treatment combinations Weight of Dry Leaves: Leaves dry weight was statistically significant due to four sowing times. It varied from.9g to.g. The highest weight (. g) of dry leaves was observed in the treatment T (8 November) which was statistically similar to the treatment T (8 ) and the lowest (.9 g) was found from T (8 ) (Table ). The significant result was found in respect of dry weight of leaves of. It varied from.6g to 7.75g. The S (cm cm) treatment gave the maximum weight (7.75g) of dry leaves and the minimum (.6 g) was found in treatment S (cm cm) that was statistically similar to the treatment S (5cm 5cm) (Table ). The combined effect of sowing time and spacing was statistically significant in respect of leaves dry weight. It varied from.g to 8.97g. The maximum leaves dry weight (8.97g) was found in the treatment T S which was statistically similar to that of T S and T S and the minimum (.g) was in the treatment T S which is statistically significant to that of T S and T S (Table ). Root Length: The root length of was significantly influenced by four sowing times (Table ). The longest root (.cm) was observed from the plants grown on 8 November (T ) which was significantly similar to the plants grown on 8 (T ) but significantly differed from other sowing dates. The shortest root (6.69 cm) was found from the plants grown on 8 (T ). This was also significantly differed from other sowing dates. A statistical similar result was also found from the treatment T (8 ) and T (8 ). This result showed that the root length progressively increased with the planting of late November (T ) and early (T ) but decreased with the planting of mid- (T ) to late- (T ). The present

5 Intl. J. Sustain. Agric., 5 (): 9-6, Table 5: Effects of sowing time and spacing on diameter of root (cm) of Diameter of root (cm) - Spacing T T T T.bc.9de 9.7ef 8.6f.65b 7.ab.79bc.8bc.6de.a.9a 6.67ab.5bc.8cd 5.97a Sowing dates 7.a.ab.b.8b.65 T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm Table 6: Effects of sowing time and spacing on weight of fresh root (g) of Weight of fresh root (g) Spacing T T T T 6.5de.de 8.e 6.9g 5.7 c 6.7bc 58.bc.cd 88.5fg 7.7 b 7.a 78.b 5.cd 9.97f 6. a Sowing dates 7.5 a 56.5ab 9.9b 8.8c 7.88 T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm results agreed with Rashid and Shakur []. There was a significant difference among the different spacings of production in respect of root length (Table ). The largest root (. cm) was recorded from the plants grown at the spacing of cm cm (S ) which was significantly similar to the plants grown at the spacing of 5cm 5cm (S ) and the smallest root was recorded from the plants grown at the spacing of cm cm (S ), which was statistically significant compared to others. A significant interaction was found between sowing time and spacing on root length of (Table 5). The root length ranged from 6.cm to.8cm. The longest root (.8cm) was recorded from the treatment TS. The shortest root (6.cm) was found from the treatment TS that was statistically similar to that of TS and TS. The plants grown at the spacing of cm cm (S ) uptook more nutrients and rate of photosynthesis was higher than other plants so that vegetative growth was increased and the roots were rich in carbohydrate. They got more space to develop than other plants. So the root length was increased. Diameter of Root: Root diameter exhibited significant variation among the four sowing times (Table 5). The root diameter was progressively decreased with the advance of sowing date. The highest root diameter (7. cm) was obtained from the plants grown on 8 November (T ), which was statistically similar to the plants grown on 8 (T ). The lowest root diameter (.8cm) was obtained from the plants grown on 8 (T ), which was statistically similar to the plants grown on 8 (T ). The findings of the present study in root diameter agreed with Bose et al. []. Significant difference was observed among the different spacing of production in respect of root diameter (Table 5). The maximum root diameter (5.97 cm) was found from the plants sown at the spacing of cm cm (S ) which was statistically similar to that of the spacing of 5cm 5cm (S ) while the minimum root diameter (.65 cm) at the spacing of cm cm (S ). The plants under the treatment S (cm cm) had to have sufficient space to develop their root in soil so that the root diameter was increased enough than others. The findings agreed with McCollum et al. []. The interaction effect of sowing time and spacing statistically influenced the root diameter of (Table 5). The root diameter varied from 8. cm to.9 cm. The highest root diameter (.9) was observed from the treatment combination of TS where plants were grown at the spacing of cm cm and grown on 8 November (T ). The plants under the treatment TS were statistically similar to that of TS. Weight of Fresh Roots: Weight of fresh roots was significantly differed by four sowing times (Table 6). The highest fresh root weight (7.5 g) was observed from the plants grown on 8 November (T ), which was significantly similar to the plants planted on 8 November (T ). The lowest fresh root weight (8.8 g) was observed from the plants grown on 8 (T ). The results were in agreement with the findings of Rashid and Shakur []. They reported that is a photo and thermo sensitive crop. Growth of root was developed under a sustainable environmental condition. Later sowing could not provide their suitable environmental conditions to grow up properly. So earlier sowing was the best for higher fresh weight of root. Different spacing for production was found to have significant effect on fresh root weight (Table 6). It ranged from 5.7g to 6.g. The maximum fresh root weight (6.g) was obtained from the plants grown at the spacing of cm cm (S ), which was significantly differed from others. The minimum fresh root weight (5.7g) was obtained from the plants

6 Intl. J. Sustain. Agric., 5 (): 9-6, Table 7: Effects of sowing time and spacing on weight of dry root (g) of Weight of dry root (g) Spacing T T T T 8.6cd 5.6 de.7 a 8.7g.78b 5. b 8.6 cd 5.6de. fg 8.9a.7 a 5.b 7.6 cd.57 fg.8a Sowing dates 5.5a.99b 6.6c.d 8.7 T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm grown at the spacing of cm cm (S ). The plants, which were grown under the spacing cm cm (S ), had more space to develop their roots and had lesser nutrient competition. Whatever the plants grown under the spacing of 5cm 5cm (S ) and cm (S ) cm had comparatively less space and they had a nutrient competition among the plants. The interaction effect of sowing time and spacing was statistically significant in respect of weight of fresh root (Table 6). The weight of fresh root ranged from 7.g to 6.9g. The maximum fresh weight (7.g) was recorded from the plants grown at the spacing of cm cm and planted on 8 November i.e. combined treatment TS while the minimum ( 6.9g) at the spacing of cm cm and planted on 8 i.e. combined treatment TS which was statistically similar with TS. The highest weight of fresh root was statistically differed from other treatment combinations. Weight of Dry Root per Plant: Significant variation of root dry weight among four sowing times was recorded which varied from 5.5g to.g (Table 7). The maximum root dry weight was observed to the plants grown on 8 November (T ) and the minimum on 8. It found that root dry weight was gradually st th decreased from sowing date (T ) to sowing date (T ). The roots were produced under optimum environmental condition like temperature, light and humidity on 8 November in compare to others. It was probably the reduction of photosynthesis and possible backflow of carbohydrate and unable to synthesize carbohydrate. Further, Reduction of root dry weight was resulted from non-accumulation of food due to aging of plants and less of stored reserved due to respiration. The effect of different spacing significantly influenced in respect of root dry weight (Table 7) which varied from.8g to.78g. The maximum root dry weight was found at Number of cracking root (%) T T T T Sowing time Fig. : Effect of sowing times on the number of cracking root percentage of the spacing of cm x cm (S ) which was similar to the spacing of 5cm x 5 cm (S ) and the minimum was found at the spacing of cm x cm (S ). It resulted that wider spacing (S ) gave more consumption of dry mater of root than less densely grown of. The result was agreed by Amjad and Anjum [6]. The combined effect of four sowing times and different spacing significantly influenced the root dry weight (Table 7). The root dry weight varied from.7g to 8.g. The maximum root dry weight (.7g) was obtained on 8 November (T ) at the spacing of cm x cm (S ) i.e. The combined treatment of T S gave the highest result and the minimum root dry weight (8.g) was observed on 8 (T ) at the spacing of cm x cm (S ) i.e. combined treatment of T S gave the lowest result. The highest root dry weight represented by T S was statistically similar with T S. The lowest root dry weight represented by T S was statistically similar with T S and T S. Percentage of Cracking Root: The percentage of cracking root was varied significantly among the four sowing times (Fig. ). The maximum cracking percentage (.5%) was obtained from T treatment i.e. delay sowing gave a huge amount of cracking roots. But the early sowing i.e. T treatment gave minimum percentage of cracking root which was.7%. This might be caused by early sowing helps in development and vigorous growth of root. The value of cracking percentage with the treatment of three spacing varied significantly (Fig. ). The maximum percentage (.7%) of cracking root was observed in the treatment of S (cm cm) while the minimum (6.55%) in S (cm cm). The combined effect of different sowing times and spacing was highly significant among the treatment. The maximum cracking percentage of root (8.%) was observed from the treatment of TS which was statistically similar with TS. The minimum (.6%) cracking percentage of root.5 T T T T

7 Intl. J. Sustain. Agric., 5 (): 9-6, Number of cracking root (%) Number of branched root (%) Number of branched root (%) Spacing Fig. : Effect of spacing on the number of cracking root percentage of.57. T T T T.5 Sowing time.69 Spacing.. Fig. 5: Effect of sowing times on number of branched root percentage of Fig. 6: Effect of spacing on the number of branched root percentage of. was observed from the treatment of TS which was statistically similar with TS and TS. The result showed that the early and dense sowing influenced positively on growth of plant. All the process of consumption of nutrient, air, water and light to become a competitive situation under less spacing comparatively than wider spacing. Percentage of Branched Root: The percentage of branched root was varied significantly among the four sowing times (Fig. 5). It ranged from 5.7% to.%. The maximum percentage (.%) of branched root was found T T T T Table 8: Interaction effect of plant height (cm), gross yield (kg/plot), gross yield (t/ha), marketable yield (kg/plot), marketable yield (t/ha),% of cracking root and% of branched root of Treatment Combination % of cracking root % of branched root T.67 f 5. g T.8 ef 6.fg T.9 ef 5.77 fg T 5. e 9. ef T 7.5 d. e T.7 c. c T 6. de 5. d T. c 5. d T 8. a. a T.7 bc 9. c T 6.6 a.6 c T.7 b 6. b CV% T = 8 November, T = 8 November, T = 8, T = 8 S = cm cm, S = 5cm 5cm, S = cm cm on 8 (T ) which was statistically similar to that of 8 (T ). The minimum percentage (5.7%) of branched root was found on 8 November (T ) i.e. delay sowing gave a huge amount of branched root. But the early sowing i.e. treatment T gave minimum percentage of breached root. This might be caused by adverse environmental conditions like temperature, humidity, light and rainfall. The value of branched percentage with the treatment of three spacing varied significantly (Fig. 6). It ranged from.5% to.%. The maximum percentage (.%) of branched root was observed to the plants planted at the spacing of cm x cm (S ) and the minimum percentage (.5%) of branched root was obtained at the spacing of cm x cm (S ) which similar to the spacing of 5cm x 5cm (S ). The result showed that the smallest spacing (S ) gave maximum branched root percentage and minimum branched percentage was found from the highest spacing (S ) (Fig. 5). The combined effect of different sowing times and spacing was highly significant in respect of branched root (Table 8). The maximum percentage (.%) was observed from the treatment of T S and the minimum percentage (5.%) was observed from the treatment of T S which was statistically similar to that of T S and T S. The result showed that the early sowing in association of dense planting effected on plant growth and development as well as the development of root. 5

8 Intl. J. Sustain. Agric., 5 (): 9-6, REFERENCES. McCollum, T.G., S.J. Locascio and J.M. White, 986. Plant density and row arrangement effects on. Bose, T.K. and M.G. Som, 986. Vegetable crops in yields. J. Amer. Soc. Hort. Sci., (5): India. First Edn. Naya Prakassh, Calcutta, India, -. Dragland, S., 986. Plant density and row spacing 9: 9-5. in s. Forskning of Forsiki Landbruket,. Barnes, N.C., 96. Effect of some environmental 7(): 9-5. factors on growth and colour of s. Bulletin. Nogueira, I.C.C., F.C. Nogueira and M.Z. de Cornell Univ. Agric. Expt. Sta., pp: 86. Negreiros, 98. Effect of plant spacing on yield of. Alim, A., 97. An Introduction to Bangladesh (Daucus carota L.) cv. Kuroda Nocional. Agriculture. First Edition, M. Alim, Dhaka, pp: 9. Proc. Trop. Reg., Amer. Soc. Hort. Sci., 5: Rashid, M.M., 99. ``Shabjir Chash'' (in Bangla).. Rashid, M. and M.A. Shakur, 986. Effect of date of Published by Begum Shahla Rashid. BARI planting and duration of growing period on the yield Residential Area, Joydebpur, Gazipur, Dhaka, pp: 7. of. Bangladesh Horticulture, (): Yawalker, K.S., 985. Vegetable crops in India.. Mack, H.J., 979. Effect of fertilizers, row spacing and Third edition. Mrs. K.K. Yawalker, Agri-Horticultural harvest dates on table s. J. Amer. Soc. Hort. Publishing House, 5, Bajaj Nagar-, Sci., (5): pp: Salter, P.J., L.E. Currah and J.R. Fellows, 979. The 6. Freman, R.E. and P.K. Simon, 98. J. Amer. Soc. Hort. effect of plant density, spatial arrangement and time Sci., 8(): of harvesting on yield and root size in s. J. 7. Woolfe, J.A., 989. Nutrition Aspects of Sweet Agric. Sci., 9(): -. potato Roots and Leaves. Improvement of sweet 6. Amjad, M. and M.A. Anjum,. Effect of root size, potato (Ipomea batatas) in Asia; CIP, pp: plant spacing and umbel order on the quality of 8. Pavlek, P., 977. Effect of plant density on seed. Department of Horticulture, University of yield. Plojprivredna Znanstvena Smotra, : Agriculture, Faisalabad-8, Pakistan. International 9. Lipari, V., 975. Yield, growth pattern and Journal of Agriculture and Biology, (): 9-. morphological characteristics of root in the 7. Bussell, W.T. and J. Dallenger, 97. Baby : a autumn-winter spring cycle in relation to planting report on main crop varieties trials,. New Zealand density and maturing. Rivista di Agronomia, Commercial Grower, 7(9): 9-. 9(/): -5. 6