J.Sc. Tech 11(2) 2010

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Journal of Science and Technology 11 (2) March 2010 ISSN 1605 427X Sudan University of Science and Technology www.sustech.edu Effect of Watering Intrvals and Weeding on Growth and Yield of Sunflower (Helianthus annuus l) S. O. Yagoub, A. A. M. Osman and A. K. Abdesalam 1-Department of Agronomy, Faculty of Agricultural Studies University of Sudan for Science and Technology, Shambat, Sudan. 2-Distance education, University of Sudan for Science and Technology, Khartoum -Sudan ABSTRACT: Field experiments were conducted in ( 2006\07 and 2007\08) growing seasons in the Demonstration Farm of University of Sudan for Science and Technology, Shambat to investigate the effects of irrigation intervals (7, 15, 21 and 30 days), and ( and non ) on growth, yield and yield components of sunflower cultivar Haysun33. The experiment was laid out in factorial randomized complete block design with four replications. The results revealed that, the growth parameters ( plant height, number of leaves and stem diameter),and yield components (head diameter, head weight, number of seed per head, empty seed per head, 100seed weight and yield per unit area) gave significant differences due to application of watering intervals. The irrigation interval every 7 and 14 days give better growth and yields. On the other hand, and non have no clear effect on all above parameters. In conclusion, sunflower was sensitive to long irrigation intervals, but not for and non. KEY WORDS: Watering intervals, Weeding, Growth, Yield and Sunflower. INTRODUCTION Sunflower ( Helianthus annuus L.) is a member of the family composite. In Sudan, sunflower emerged recently as an important cash crop, to strengthen the economy and to fill the gap in vegetable oil production for domestic consumption. Moreover, sunflower provides a high value animal feed in addition to the fact that the oil is used as a raw material for manufacturing of paints and cosmetics. Accordingly, the area grown with this crop has increased tremendously during few years (Ali, 1989). Satisfactory yield of 5 to 8 metric tons/feddan can be obtained on the central clay plains of Sudan, which meet the edaphically and climatic needs of sunflower (Ali, 1989). The production of sunflower in resent years increased from 44 thousand tons in season 2005/06 to 73 thousand tons in 2006/07 by rate of 65.9% due to the increased in production area from 87 thousand fadden in 2005/06 seasons to 161 thousand in 2006/07seasons by rate of 85.1%( CBS, 2007) The problem of raising agricultural production to meat the high population demand for food and vegetable oils will lead to more water utilization, at the time water is undergoing scarcity. Hence, use of limited water is vital.cox and Jolliff(1986) confirmed that sunflower is better adapted to regions of prolonged drought, because of its ability to extract stored soil water in the deeper soil profile. Also sunflower has well developed and branched root system, and maintains open stomata under condition of high 52 evaporation demands that usually prevail in hot arid and semi arid regions (Rawson and Constable, 1980). Weeds compete with sunflower causing poor growth and yield losses. Yield losses from weed competition depend on weed species, time of infestation, weed density and climatic conditions. The first four weeks after emergence is most critical in determining weed competition damage, so early weed control is essential. The yield reduction due to weeds in sunflower is estimated to be as high as 81% (Jaykumar et. al., 1988). Therefore, the objective of this study is to investigate the interactive effect of watering intervals and effect of and non on growth and yield of sunflower. MATERIALS AND METHODS A field experiment was conducted for tow consecutive seasons ( 2005\06 and 2006/07) in the Demonstration Farm of the Faculty of Agricultural Studies, Sudan University for Science and Technology,Shambat Sudan (latitude 15o 40' N longitude 32o 32' E and latitude 230 m asl). The climate of the locality is tropical semi- arid with mean annual rainfall of 100 to 200 mm and maximum temperature of about 42o c in summer and low temperature of 21o c in winter. The soil of the experimental site is clay (fine montomrilonitic, isohyperthe - rmicentic chromustert), with alkaline ph and low nitrogen content. The experiment was designed to study the effect of four levels of irrigations R1 ( 7 days), R2 ( 15 days), R3 (21 days) and R4(30 days), and

two level of W1 () and W2 (no ) on sunflower cultivar hybrid Hysun 33,which were obtained from Safola Company at Khartoum.. The layout of the experiment was a factorial randomized complete block design with four replications. The area of the experiment was divided into 32 plots of 6x5 meter, each plots consist of 6 ridges 6 meter long and 70 cm a part. The crop was seeded during the first week of December in both seasons, 2-4 seeds were sown per hole at 20 cm between holes on the top of the ridges. Nitrogen fertilizer was applied in the form of urea (46%N) at 1N basal dressing before the second irrigation. Irrigation was applied immediately after sowing; subsequent irrigation interval was 7-10 days and then after well establish of crops (30 days after sowing) the irrigation practice were applied. After two weeks from sowing seedling were thinned and was done once every 4 weeks after planting for the two seasons for treatment and the other plots was left without until the harvest. Ten randomly selected plants were taken from the two inner ridges and then mean of plant height (cm), number of leaves and stem diameter(cm) were measured 4 times, the first after one month from crop emergence( after month and half of sowing date).then after 15 days continuously. Heads of one meter from the middle ridge were cut manually when dry and become brown in color approximately 100 days after sowing. Heads of each plots were left to dry, then threshed to measure the following parameters, head weight (gm),head diameter (cm), number of seeds / head, number of empty seeds / head, 100 seed weight (gm) and yield ton/ha. Data was generated to MSTAT Computer Software for statistical analysis. RESULTS AND DISCUSSION Effect of watering intervals, and non for the growth characteristics measured (plant height, leaf number and stem diameter) during growth of sunflower indicated significant differences (Table 1-2 and 3)for both seasons for four cuttings. Also yield components revealed significant differences, presented in (Table 4 and 5) due to application of watering intervals. Water deficits have been shown to decrease both growth and yield (Flaggela, et. al., (2002). This is because many important physiological processes, such as leaf enlargement, stomata opening and photosynthesis are directly affected by reduction in leaf water potential. The effect of watering intervals, and non on plant height were presented in (Table 1), and showed that the irrigation interval of 7 days of plants (W1R1) gives the highest value for both season for the fourth cutting of two seasons. Generally irrigation every 7 and 14 days for four cutting and two seasons gave better plant height, and irrigation at 30 days gave the lowest value. This result was on line with Teama and Mohammed (1994) who reported reduction in plant height if any water stress occurred from seedling stage to just before flowering, while stress at or after flowering had no effect on plant height. Weeding and none showed un consistent variation and there were no clear evidence for their effects. Data of number of leaves for both seasons was presented in table 2. The result revealed that irrigation interval every 30 days for and non (W1R4 and W2R4)gave small number of leaves compared with other treatments for all cuttings. Table 1.The effect of four watering intervals, and non on plant height of sunflower for four cutting during seasons (2004/05 and 2005/06) 53 W 1 R 1 15.4 a 64.7 a 102.6 a 114.1 a 43.63 a 132.1 a 140.6 a 153.2 a W 1 R 2 15.13 a 66.93 a 113.6 a 117.5 a 40.50 b 119.3 bc 133.5 b 147.8 a W 1 R 3 11.57 b 54.7 b 93.9 b 100.7 b 37.07 c 112.1 cd 122.8 c 137.8 b W 1 R 4 10.87 c 41.63 c 70.93 c 79.27 c 43.14 de 102.9 ae 116.5 c 133.4 bc W 2 R 1 10.77 b 63.67 a 108.3 a 123.3 a 41.36 ab 124.4 ab 132.7 b 134.4 bc W 2 R 2 12.93 b 66.93 a 89.23 b 98.27 b 37.49 c 113.1 cd 132.0 c 137.3 b W 2 R 3 14.27 b 58.33 b 90.83 b 96.27 b 35.29 cd 106.3 de 119.1 c 134.0 bc W 2 R 4 12.30 b 55.07 b 93.03 b 90.1 b 32.03 e 95.03 f 107.6 d 129.3 c CV% 15.81 15.16 13.12 13.56 3.47% 3.92 3.05 2.53 SE 1.17 5.03 7.21 8.20 0.7592 2.563 2.192 2.03 LSD0.05 3.57 15.26 21.9 24.90 2.303 7.77 6.469 6.157

This was confirmed by (Jamro and Larik, 1991) who revealed that when moisture stress was imposed during vegetative stage, short plant with fewer leaves developed. But Marc and Palmer (1976) found that stress imposed 10-20 days after sowing reduced leaf and when the stress period was extended by 10 days there was no further significant reduction in leaf number. Table 2. The effect of four watering intervals, and non on number of leaves of sunflower for four cutting during seasons (2004/05 and 2005/06) W 1 R 1 11.03 b 19.47 b 21.40 b 20.87b 39.33 b 43.67 abc 56.00 a 72.00 a W 1 R 2 11.47 b 22.13 b 23.20 a 23.63 a 35.33 bc 40.67 bcd 55.67 abc 64.00 bc W 1 R 3 9.36 b 20.67 b 22.20 a 14.27 b 33.00 bc 37.33 cde 54.33 bc 64.00 bc W 1 R 4 9.133 c 15.27 c 16.40 c 12.47 e 30.33 c 34.00 e 51.00 c 60.67 c W 2 R 1 10.53 b 20.80 b 21.13 b 22.13 a 46.33 a 49.00 a 65.33 a 72.00 a W 2 R 2 12.13 a 21.33 b 20.8 b 18.33 c 39.33 b 44.67 ab 54.33 bc 69.67 ab W 2 R 3 10.4 b 21.47 b 21.47 b 14.53 d 34.67 bc 39.00 bcde 55.67 abc 64.00 bc W 2 R 4 10.0 b 17.40 c 20.67 b 18.80 c 32.00 c 36.33 de 51.33 c 59.00 c CV% 11.5 21.7 12.9 19.0 9.74 8.51 8.60 5.01 SE 0.70 3.0 1.56 1.99 2.041 1.994 2.944 1.914 LSD0.05 2.12 9.0 4.7 6.01 6.19 6.048 8.928 5.807 The effect of watering interval, on the stem diameter of sunflower showed significant differences, but in the first season there were no evidence for which treatment of irrigation was the best one, as the first cutting W2R2 was the highest one, while, W1R4 and W2R1 were the lower. Teama and Mahmoud (1994) found that water stress before flowering gave the greatest reduction in stem compared to that at flowering and or at maturity. All above growth parameters (plant height, number of leaves and stem diameter), showed no response for and non. Robinsone et. al.,1967 found that sunflower can compete with weed because it give long and high leaf area that covered weeds. Table 3.The effect of four watering intervals, and non on stem diameter of sunflower for four cutting during seasons (2004/05 and 2005/06 ) W 1 R 1 0.43 b 1.09 b 1.32 b 1.24 b 11.23 a 13.92 a 16.40 a 18.37 a W 1 R 2 0.52 a 1.25 b 1.52 a 1.46 b 8.83 b 10.57 b 12.66 b 14.87 b W 1 R 3 0.37 b 1.16 b 1.39 b 1.44 b 8.13 b 10.11 b 12.33 bc 14.87 b W 1 R 4 0.35 c 0.76 c 1.27 c 1.12 c 7.67 bc 9.67 b 12.73 b 15.20 b W 2 R 1 0.35 c 1.26 a 1.40 b 1.57 a 6.67 c 8.57 c 9.67 cde 12.00 cd W 2 R 2 0.44 b 1.22 a 1.40 b 1.27 b 4.50 d 6.53 d 10.33 bcd 13.53 bc W 2 R 3 0.45 b 1.14 a 1.27 c 1.38 b 4.80 d 5.60 d 8.03 de 10.53 d W 2 R 4 0.37 b 1.32 a 1.32 b 1.43 b 4.11 d 5.50 d 7.13 e 9.96 d CV% 15.01 22.01 13.4 16.3 9.84 8.89 13.37 8.30 SE 0.36 0.14 0.106 0.129 0.397 0.452 0.8608 0.655 LSD0.05 0.11 0.44 0.32 0.39 1.206 1.371 2.611 1.987 The effects of watering intervals and and non on yield characteristics of sunflower was presented in (Table 4 and 5). The prolonged irrigation periods W3 and W4 significantly reduced the mean head diameter compared to other irrigation treatments ( W1 and W2) for the two seasons. Moreover, and non revealed no significant difference. Yield and yield component were positively affected by irrigation( 54 Falgella et. al.,2002 and Asbagh et.al.,2009. Ahmed (2006) reported similar observations and attributed the reduction in head diameter under prolonged irrigation to reduction in leaf development. Head weight and number of seed per head also showed significant differences due to the prolonged irrigation interval (Table 4). This was in line with the finding reported by Tomar et al.(1999) who indicated that water stress reduced the

number of seed per head due to increase in flower and seed abortion. Moreover, the reduction in head diameter may explain the reduction in number of seeds per head observed in this study. This was in line with the finding reported by Cox and Jolliff(1986) and Teama and Mohamoud (1994). They indicated that in addition to reduction in head diameter, water stress reduced the number of seeds per head by increasing flower and seed abortion. Table 4. Effect of watering intervals and on head diameter, head weight and number of seed per head of sunflower for two seasons 2005/06 and 2006/07. Watering Head diameter Head weight Number of seed per head intervals Weeding non 2005/06 7 17.2 17.2 81.0 57.3 775.76 756.33 15 15.7 15.8 31.5 30.2 607.0 505.5 21 15.1 14.8 30.0 31.0 531.4 374.0 30 14.8 14.3 27.2 30.2 404.2 331.1 Mean 15.7 15.5 42.4 37.0 579.5 491.7 LSD 2.3 10.6 141.8 C.V. (%) 8.3 15.14 15.12 2006/07 7 21.7 18.6 63.6 54.1 1119.0 947.3 15 19.6 16.8 43.1 32.9 837.1 698.7 21 18.9 17.8 41.9 37.8 790.5 753.5 30 15.4 13.9 26.0 21.7 559.3 537.8 Mean 18.9 16.8 43.6 36.6 826.4 734.3 LSD 1.81 14.25 198.2 C.V. (%) 5.79 20.27 14.5 The mean 100 seed weight showed significant difference, (Table 5). Supporting evidence was reported by Khalifa(1984) and Ahmed (2006) who attributed the reduction in the 100 seed weight under water stress to the reduction in dry matter and mutual shedding of leaves which caused early leaf senescence. The number of empty seeds per head was significantly different due to prolonged watering interval. The reduction in seed weight was associated with substantial increasing in percentage of empty seeds per head. It was hypothesized that water stress particularly at flowering stage reduced fertilization and seed set due to dehydration of pollen grain. Ishag (1988) reported similar results and noticed the presence of large number of empty seeds per head when sunflower was subject to water stress at flowering stage. Consequently, the reduction in seed yield per unit area observed in this investigation may be attributed to the reduction in head diameter, number of seeds per head and 100 seed weight. Similar results were obtained by many researchers (Kadayific and Yiledrim, 2000, Prasad et.al., 2001). They attributed the reduction in seed yield under water stress to the reduction of the above mentioned yield components. Table 5. Effect of watering intervals and on 100seed weight, number of empty seed and yield (ton/ha) of sunflower for two seasons 2005/06 and 2006/07. Watering intervals Weight of 100 Number of empty seed Yield /area(ton/ha) 2005/06 7 8.000 6.633 167.0 163.3 3.33 2.80 15 6.700 6.233 123.2 121.0 2.97 2.37 21 4.367 4.330 116.4 124.4 1.90 1.87 30 3.733 3.833 180.3 154.9 1.63 1.50 Mean 5.7 5.257 146.7 140.9 2.45 2.13 LSD 1.8 42.0 0.6 C.V. (%) 18.87 16.68 16.14 55

Watering intervals Weight of 100 Number of empty seed Yield /area(ton/ha) 2006/07 7 7.133 6.633 247.0 218.5 3.63 3.74 15 5.867 4.833 198.0 166.4 3.09 2.93 21 5.333 5.100 186.0 181.9 2.68 2.57 30 4.300 4.100 126.7 116.7 1.15 1.04 Mean 5.658 5.166 189.4 170.8 2.63 2.57 LSD 1.235 35.69 0.66 C.V. (%) 13.02 11.3 15.53 REFERENCES 1. Ahmed, F.E., B. E. M Ahmed and M. F. Ahmed ( 2006 ). Effect of irrigation interval and planting density on seed and oil yields of sunflower hybrid. Uof K. J. Agric. Sci. 14(3) 343-353. 2. Ali, F. M. (1989). sunflower agronomy summer season. Annual Report, Gezira Research Station ARC. Wad Madani. Sudan. 3. Asbagh, F. T., A. F. Moghddam and A. H. Gorttapeh ( 2009 ). Influence of water stress and sowing data on sunflower yield and oil percentage. Research journal of Biological Science 4 (4): 487 489. 4. CBS (2007) central Bank of Sudan Annual Report (47) 90 91 Alsadad printer Khartoum Sudan 5. Cox, W. J. and Jolliff, G. D (1986). Growth and yield of Sunflower and Soybean under soil water deficits. Agronomy Journal 78, 226 230. 6. Flagella, Z., T. Rotundo, E Tarantino, R. Dicatering and A. De Caro (2002). Changes in seed yield and oil fatly acid compotation of high oleic sunflower ( Helianthus annuus L ) hybrids in relation to the sowing date and water regime. Agron. J, 17 : 221 230. 7. Ishag,H.M.(1988). Sunflower new crop for Sudan. Procedding of fourth oil crop net work at Njoro, Kenya 25-29 January. 8. Jamro, G.H.and A.S. Laric, (1991). Influence of water stress on photosynthesis N fixation and development in Glycine max L. Pak. Phyton 3:19-26. 9. Jaykumar. R., Premsekar. M.,Kempuchtty, and Subramaniam., S.(1988). Effect of integrated weed management on yield andquality of sunflower. Madras Agric.J.,75: 305. 56 10. Kadayifci, A. and Yildrin O. (2000). Response of sunflower seed yield to water. Turkish Journal of Agriculture and Forestry 24 (2), 137 145. 11. Khalifa, F. M. (1984). Effect of spacing on growth and yield of sunflower ( Helianthus annuus L. ) under two systems of dry farming in Sudan. Journal of Agricultural Science, Cambridge 103, 213 220. 12. Marc, J. and Palmer J. H. (1976). Relationship between water potential of leaf and inflorance initiation in ( Helianthus annuus L.) physo plant 36 : 101 104 13. Prasad V. K., Yadva V. K., Prasad T. N., Kumar A and Prasad S.M (2001). Effect of irrigation and nitrogen on oil percentage, yield and water use efficiency of winter sunflower ( Helianthus annuus L.) Indian Journal of Agronomy 46 (1) 171 176. 14. Robinson R. G. Johnson F. K and Soine O.C (1967). The Sunflower Cropping Minnesota crop Agric. Ext. Bull 299 : 1-31 cited by Johnson B. J. weed Science, 1971 19 (4) 372 380. 15. Rawson, H.M., and Constable, G.A., (1980). Carbon production of sunflower cultivars in field and controlled environment. I. photosynthesid and transpiration of leaves, stem and heads, Ausr. J.Plant Physio.7:555-575. 16. Teama, E.A., and Mahmoud, A.M.,(1994). Response of sunflower to wateing regimes and nitrogen fertization1: growth characteristics. Assuit J. Agric.Sci.(25):29-37. 17. Tomar, HP. S., Dadhwal, K. S. and Singh H.P (1999). Effect of irrigation on yield and yield attabites of spring sunflower (Helianthus annuus L.) Tropical Agriculture (76 (4) 228 231.