Effects of red root pigweed, Amaranthus retroflexuxs L. interference times on yield of cowpea, Vigna unguiculata L.

Subject Areas : Agroecology Journal

Bahram Mirshekari ¹

1 - Assistant Professor of Agriculture Faculty, Islamic Azad University, Tabriz Branch

Received: 2007-12-27 Accepted : 2008-07-29 Published : 2008-08-22

Keywords: yield, Cowpea, Interference, Red root pigweed,

Abstract :

Red root pigweed is the third dicotyledonous dominant weed of crops in the world from view point of yield loss. In order to quantify the interaction of cowpea yield to different times of red root pigweed (RP) interference, an experiment was conducted at research field of Islamic Azad University of Tabriz, Iran, based on randomized complete block design with three replications. The treatments were RP interference times (2, 4, 6, 8, 10 weeks after cowpea emergence), full season interference and weed free plot as control. In all treatments, RP was seeded immediately after cowpea planting and removed after treatment levels. Analysis of variance indicated that effect of treatments on all traits was significant. The highest (79%) and the lowest (25%) green cover percentages were measured at flowering stage in weed free, and full season interference treatments, respectively. Cowpea biomass in weed free plot (3895 kg ha-1) was similar to treatment of two weekly RP interference in early growth stage of cowpea (3889 kg ha-1). With increasing RP interference time, pod numbers in each plant decreased more than other traits. The highest reduction in thousands seed weight (70.13%) compared to control was observed in full season RP interference. Crop yield in full season RP interference treatment decreased up to 98.49% compared to control. With considering of maximum acceptable yield loss (10%) and results of this research, interference time of RP must not be longer than 4 weeks in early growth stage of green bean.                         

References:

1- استادیار گروه زراعت و اصلاح نباتات دانشگاه آزاد اسلامی واحد تبریز، دانشکده کشاورزی[e-mail]

منابع

1- راشد محصل، م. ح.،  ح. رحیمیان و م. بنایان. 1371. علف‏های هرز و کنترل آن‏ها (ترجمه). انتشارات جهاد دانشگاهی مشهد.

2- عبداللهی، ع.، غ. احمدی، ر. محمدی، ن. بهرامی و ر. حق‏پرست. 1383. تعیین دوره بحرانی کنترل علف­های هرز در زراعت نخود معمولی پاییزه (Cicer arietinum). هشتمین کنگره علوم زراعت و اصلاح نباتات ایران، دانشکده علوم کشاورزی دانشگاه گیلان.

3- کوچکی، ع.، ح. رحیمیان، م. نصیری محلاتی و ح. خیابانی. 1373. اکولوژی­ علف­های­هرز. انتشارات جهاد دانشگاهی مشهد.

4- مظاهری، د. 1377. زراعت مخلوط. چاپ دوم، انتشارات دانشگاه تهران.

5- میرشکاری، ب. 1382. علف­های­هرز و مدیریت آن ها. انتشارات دانشگاه آزاد اسلامی تبریز.

6- یدوی، ع.، م. آقاعلیخانی و ع. م. مدرس ثانوی. 1383. دوره بحرانی کنترل علف­های هرز لوبیا چیتی در لردگان. چکیده مقالات هشتمین کنگره علوم زراعت و اصلاح نباتات ایران، دانشکده علوم کشاورزی دانشگاه گیلان. صفحه 294.

7. Bosnic, A. C. and C. J. Swanton. 1997. Influence of barnyard grass (Echinochloa crus- galli) time of emergence and density on corn (Zea mays L.). Weed Science 43: 276-282.

8. Clarence, J. and J. Swanton. 2002. Determination of the critical period of weed interference in corn (Zea mays L.) and soybeans (Glycine max L.). Journal of Crop Science 39: 49-60.

9. Cowan, P., S. E. Weaver and C. J. Swanton. 1998. Interference between pigweed (Amaranthus spp.), barnyardgrass (Echinochloa crus-galli) and soybean (Glycine max). Weed Science 46(5): 533-539.

10. Dieleman, A., A. S. Hamill, S. F. Weise and C. J. Swanton. 1995. Empirical models of pigweed (Amaranthus spp.) interference in soybean (Glycine max L.). Weed Science. 43: 612- 618. 

11. Fisk, J. W., O. B. Hesterman, A. Shrestha, J. J. Kells, R. R. Harwood, J. M. Squire and C.C. Sheaffer. 2002. Weed suppression by annual legume cover crops in no tillage corn. Agronomy Journal 93: 319-325.

12. Harker, K. N., G. W. Clayton and A. M. Johnston. 1999. Time of weed removal for canola. Proceeding of the 10th International Rapeseed Conference, Canberra, Australia.

13. Harper, F. 1983. Inter-specific competition. In: Principle of arable crop production. Pp: 198-229. Granada Publ.

14. Hartley, M. J. and A. J. Popay. 1992. Yield losses due to weeds in sugarbeet, corn and dwarf beans. Proceeding of the forty fifth Newzeland plant protection conference, Wellingto, Newzeland. 11-13 August 1992, 52-54.

15. Knezevic, S. Z., S. F. Weise and C. J. Swanton. 1994. Interference of redroot pigweed (Amaranthus retroflexus L.) in corn (Zea mays L.). Weed Science 42: 568-573.

16. Knezevic, S. Z., M. J. Horak and R. L. Vanderlip. 1997. Relative time of redroot pigweed (Amaranthus retroflexus L.) emergence is critical in pigweed-sorghum (Sorghum bicolor (L.) Moench.) competition. Weed Science 45: 502-505.

17. Mc Lachlan, S. M., M. Tollenaar, C. J. Swanton and S. F. Weise. 1993. Effect of corn-induced shading on dry matter accumulation, distribution and architecture of redroot pigweed (Amaranthus retroflexus). Weed Science 41: 568-573.

18. Murphy, S. D., Y. Yakubu, S. F. Weise and C. J. Swanton. 1996. Effect of planting patterns and inter-row cultivation on competition between corn (Zea mays) and late emerging weeds. Weed Science 44: 856-870.

 19. Nelson, D. C. and M. C. Thoreson. 1981. Competition between potatoes (Solanum tuberosum) and weeds. Weed Science 29: 672-677.

20. O^,sullivan, P. A., G. M. Weiss and V. C. Kossatz. 1985. Indics of competition for estimating rapeseed yield loss due to Canada thistle. Canadian Journal of Plant Science 65: 145-149.

21. Patterson, D. T. 1985. Comparative ecophysiology of weeds and crops. I: Reproduction and ecophysiology. Boca Raton. CRC Press.

22. Peters, N. C. B. and B. J. Wilson. 1983. Some studies on the competitioin between Avena fatua L. and spring barley. II: Variation of A. fatua emergence and development and it’s influence oncrop yield. Weed Research 23: 305-311.

23. Ronald, A. E. 2000. Amaranthus retroflexus/pigweed. U.S. Department of Agriculture., 181pp. 

24. Ronald, A. E. and E. C. Smith. 2000. The flora of the Nova Scotia. Halif Nova Scotia Museum. 746 p.

25. Spitters, C. J. T. and J. P. Vandenberg. 1982. Competition between crop and weeds: A system approach. In: Holzner, W. and N. (eds.), Numata biology and ecology of weeds Dr. W. Junk Publication, The hague.

26. Swanton, C. J. and S. D. Murphy. 1996. Weed science beyond the weeds: the role of integrated weed management (IWM) in agroecosystem health. Weed Science 44: 437-445.