Effect of Type and Planting Date of Cover Crops on Weed Population Structure, Morphological Characteristics and Seed Yield of Sunflower (Helianthus annus L.)

Document Type : Scientific - Research


1 Department of Agronomy, Gorgan Branch, Islamic Azad University, Gorgan, Iran.

2 Department of Agronomy, Faculty of Crop Production, Gorgan University of Agricultural Sciences and Natural Resources, Iran.

3 Department of Agronomy, Gorgan Branch, Islamic Azad University, Gorgan, Iran

4 Department of Agronomy, Faculty of Agriculture, University of Shahrekord, Iran.

5 Department of Agronomy, Faculty of Crop Production, Gorgan University of Agricultural Sciences and Natural Resources, Iran


Cultivation of cover crops associated with their proper management can be a sustainable alternative to conventional weed control methods. In addition to their beneficial effects on weed control, these plants can improve soil structure and organic matter, increase water holding capacity, control soil-borne diseases, reduce soil erosion, and subsequently enhance crop yields. The use of suitable cover crops and optimizing the planting date can improve the advantages mentioned above, especially desired weeds control. They were considering the importance of sunflower production development and the need to introduce the ecological approaches in weed control; the present study aimed to investigate the efficiency of some cover crops and their optimum planting date, the influence on weed structure population and morphological traits, and sunflower seed yield (cv. Lakumka) under climatic conditions of Galougah city, Mazandaran province.
 Materials and Methods
In order to study some cover crops and their optimum planting date on controlling the weeds in sunflower production, an experiment was conducted in Galoogah city (Mazandaran province, Iran) based on a factorial split-plot arranged in a randomized complete block design (RCBD) with four replications during two growing seasons (including 2016-2017 and 2017-2018). Experimental treatments were considered to cover crops such as wheat, barley, berseem clover, hairy vetch, and different planting dates, including planting two months before, simultaneous, and two weeks after the sunflower planting. Moreover, two treatments without any cover crop cultivations, including with and without weeding, were designed as controls.
 Results and Discussion
The study results revealed that the cultivation of mentioned cover crops, regardless of types and planting dates, had a significant role in weeds control and increasing the seed yield of sunflower. In all treatments, the highest weeds dry matter was observed two months before the sunflower planting treatment. Also, barley cover crop had the lowest weeds dry matter in both experimental years in two months before the sunflower planting. It could maintain the weeds dry matter lower than other cover crops during various stages of sunflower growth. The lowest weed dry matter was observed in simultaneous planting with sunflower for all cover crops. Planting cover crops two weeks after sunflower planting also reduced the weeds dry matter. However, its efficiency was lower than the simultaneous planting of cover crops with sunflower. The highest and lowest sunflower height were observed in the treatments of berseem clover at the same time of planting and in wheat cover crop planting two months before planting of sunflower (181.76 and 105.98 cm), respectively. The highest leaf area index (3.97) was related to berseem clover cover crop in simultaneous planting date with sunflower, which was 14 and 69% more than control treatment without covering crops in weeding non-wedding conditions in two years of experiment, respectively. The lowest sunflower leaf area index was obtained from the wheat cover crop on the planting date two months before sunflower planting (first and second year 0.96 and 1.08, respectively). The highest sunflower dry matter (485.61 g.m-2) was observed in berseem clover cover crop simultaneous with sunflower planting, which was not significantly different from control treatment in weeding conditions. The lowest sunflower dry matter (108.27 g.m-2) was obtained in wheat planting two months before sunflower planting. Finally, the highest seed yield of sunflower was obtained in simultaneous planting of berseem clover with sunflower (2859.06 kg.ha-1), which was 17% higher than the control treatment without any cover crops in weeding condition (2381.1 kg.ha-1).
Simultaneous planting dates of cover crops with sunflower led to seed yield similar to weeding treatment. Even planting of berseem clover and hairy vetch had 17 and 14% enhancement in sunflower seed yield. Therefore, berseem clover cover crop planting simultaneously as sunflower planting, reduced weed growth, and increased seed yield of sunflower, it can be introduced as a solution for optimal sunflower production in sustainable agriculture.


Abaspoor, M., and Rezvani Moghaddam, P., 2009. The critical period of weed control in corn (Zea mays) at Mashhad, Iran. Iranian Journal of Field Crops Research 2(2): 182-195. (In Persian with English Summary)
Aboutalebian, M., and Mazaheri, D., 2011. Effects of hilling time and cover crop on weed control and potato yield. Iranian Journal of Field Crop Science 42: 255-264. (In Persian with English Summary)
Aghpour, M., Siahmarguee, A., Zeinali, E., Gherekhloo, J., and Kazemi, H., 2019. Investigating the efficiency of various cover crops and their elimination methods on weed populations and yield of maize forage (single-cross 444 variety). Journal of Crop Production in Press (In Persian with English Summary)
Ahmadi, K., Ebadzadeh, H.R., Kazemiyan, A., and Rafiee, M., 2018. Agricultural Statistics in 2016-2017. Ministry of Agriculture-Jahad, Iran. (In Persian)
Arabameri, R., 2008. Prediction of grain number and remobilization in wheat. MSc. Dissertation, Faculty of Agronomy, Gorgan University of Agricultural Sciences and Natural Resourseces, Iran. (In Persian with English Summary)
Asghari, J., Vahedi, A., and Khoshghol, H.R., 2011. Critical period of weed control in sunflower (Helianthus annus, L.) in west of Guilan province. Journal of Plant Protection 25(2): 116-126. (In Persian with English Summary)
Barros, J.F.C., DeCarvalho, M., and Basch, G., 2004. Response of sunflower (Heianthus annuus L.) to sowing date and plant density under mediterranean conditions. European Journal of Agronomy 21(3): 347-356.
Bolandi Amoughein, M., Tobeh, A., and Taghi Alebrahim, M., 2015. The effect of species, planting date, and management of cover crops on weed community in hybrid sunflower (Helianthus annuus). Journal of Plant Protection 29(3): 337-348. (In Persian with English Summary)
Brust, J., Claupein, W., and Gerhards, R., 2014. Growth and weed suppression ability of common and new cover crops in Germany. Crop Protection 63: 1-8.
Cabrera, M.L., Kissel, D.E., and Vigil, M.F., 2005. Nitrogen mineralization from organic residues. Reserch opportunities. Journal of Environmental Quality 34: 75-79.
Dhima, K.V., Vasilakoglou, I.B., Eleftherohorinos, I.G., and Lithourgidis, A.S., 2006. Allelopathic potential of winter cereals and their cover crop mulch effect on grass weed suppression and corn development. Crop Science 46: 345-352.
Emami Bistgani, Z., Siadat, S.A., Bakhshande, A., Alami Saeid, K., and Shiresmaeili, G.H., 2011. Effect of plant density on yield and quality traits of four sunflower genotypes. Journal of Crop Production and Processing 1: 91-103. (In Persian with English Summary)
Farokhi, E., Nabipour, A.R., and Daneshiyan, J., 1397. Instructions for sunflower production in different parts of the country. Agricultural Research Education and Extention Organization. p. 37. (In Persian)
Ghadiryan, R., Soltani, A., Zeinali, E., Kalateh Arabi, M., and Bakhshandeh, E., 2011. Evaluating non-linear regression models for use in growth analysis of wheat. Journal of Crop Production 4(3): 55-77. (In Persian with English Summary)
Hasanzade, A., Marouee Milan, R., Niko, S.H., and Khalilzade, G.H., 2013. Effect of plant density and planting date on yield and yield component in two varieties of oily Helianthus annus L. Journal of Agriculture and Natural Resources. 17: 30-40. (In Persian with English Summary)
Khajehpour, M., 2004. Production of Industrial Plants. Jehad-e-Daneshgahi Isfahan Press, Isfahan, Iran. (In Persian)
Khojamli, R., Siahmarguee, A., Zeinali, E., and Soltani, A., 2018. Effect of different winter cover crops on the dynamics of weed populations and corn growth (Single 704). Journal of Agroecology 11(2): 110-132. (In Persian with English Summary)
Jabran, K., 2017. Manipulation of Allelopathic Crops for Weed Control. Springer Briefs in Plant Science. p. 87.
Lamei Heravani, J., and Alizadeh Dizaj, K., 2014. Grass pea (Latyrus sativus) and common vetch (Vicia sativa) as suitable green manure after wheat in the cold regions of Iran. Applied Field Crops Research 27: 106-112.
Namdari, T., Ahmadvand, G., and Jahedi, A., 2010. Allelopathic effect of barley, ray and canola cover crops on weed suppression of potato. In: Third Iranian Weed Science Congress, Babolsar, Iran, 11-14 February, p. 251-254. (In Persian with English Summary)
Naseri, M.T., Koocheki, A., Nassiri, M., and Ghorbani, R., 2008. Allelopathic effects of barley straw on germination and seedling growth of corn, sugar beet and sunflower. Iranian Journal of Field Crops Research 6(1): 173-182. (In Persian with English Summary)
Narwal, S.,2004. Allelopathy in Crop Production. Jodhpur Scientific, India.
Nazari, S., Zafarian, F., Farahmandfar, E., Zand, E., and Bagheri Shirvan, M., 2012. Corn-weed interaction under different sowing dates of cover crops. Iranian Journal of Weed Science 8: 63-78. (In Persian with English Summary)
Nori-rad-davaji, A.M., and Soltani-najafabadi, M., 2015. Oilseed sunflower farming in Golestan province. Agricultural Research Education and Extention Organization, Golestan, Iran. 46 p. (In Parsian)
Parvizi, P., Najafi, H., and Gafar Zadeh, M., 2013. Survay of cover crop elimination date and type effect and sugar beet weeds population. Fifth Weed Science Community, Tehran, Iran, 10-13 September 2013, p. 200-207. (In Persian with English Summary)
Rahmani Vasu Kolai, Y., Mobaser, M., Ghanbari Malidare, A., Andar Khor, A., and Dstan, S., 2010. Determination of the best row distance and sunflower density lacumca type in Mazandaran. Research Magazine in Crop Science 2(7): 29-36. (In Persian with English Summary)
Ranjbar, M., Samedani, B., Rahimian, H., Jahansoz, M., and Bihamta, M., 2007. Influence of winter cover crops on weed control and tomato yield. Pajouhsh and Sazandegi 74: 24-33. (In Persian with English Summary)
Scott, T.W., Pleasant, J.M., Burt, R.F., and Otis, D.J., 1987. Contributions of ground cover, dry-matter, and nitrogen from intercrops and cover crops in a corn polyculture system. Agronomy Journal 79: 792-798.
Shahverdi, M., Hejazi, A., Rahimian Mashhadi, H., and Torkamani, A., 2002. Determination of the critical period for weed control in sunflower (Helianthus annuus cv. Record). Iranian Journal of Crop Science 4(3): 152-164. (In Persian with English Summary)
Sohrabi-Rad, E. M., Siahmarguee, A., Kazemi, H., Ghaderi-Far F., and Gherekhloo, J., 2017. Influence of crop management practices and soil characteristics on weed population and soil seed bank in soybean fields. Journal of Agroecology 7(1): 155-172. (In Persian with English Summary)
Soltani, H., Ghanbari, A., Rastgoo, M., and Asadi, G.A., 2017. Surveying some strategies of cultural management on species growth indices and yield in the field of soybean. Journal of Plant Protection 31(3): 396-408. (In Persian with English Summary)
Stone, L.R., Goodrum, D.E., Schlegel, A.J., Jaafar, M.N., Khan, H., 2002. Water depletion depth of seed sorghum and sunflower in the central high plains. Agronomy Journal 94: 936–943.
Teasdale, J.R., and Abdul-Baki, A.A., 1998. Comparison of mixtures vs. monocultures of cover crops for fresh-market tomato production with and without herbicide. Horticulture Science 33: 1163–1166.
Uchino, H., Iwama, K., Jitsuyama, Y., Yudate, T., and Nakamura, S., 2009. Yield losses of soybean and maize by competition with inter seeded cover crops and weeds in organic based cropping systems. Field Crops Research 113: 342-351.
USDA., 2011. United States Department of Agriculture. Available at Web site https://www.nrcs.usda.gov. (Verified 5 September 2018).
Villalobos, F.J., Sadras, V.O., Soriano, A., and Fereres, S.E., 1994. Planting density effects on dry matter partitioning and productivity of sunflower hybrids. Field Crops Research 36(1): 1-11.
Yeganehpur, F., Zehtab salmasi, S., Abedi, G., Samadivan, F., and Beyginiva, V., 2015. Effects of cover crops and weed management on corn yield. Journal of the Saudi Society of Agricultural Sciences 14(2): 178-181.
Zerai-Siahbidi, A., Rezaizad, A., and Elyaspour, S., 2017. Sunflower, coordination managment and promotion of the agricultural Jihad organization. Iran. (In Persian)