بررسی خسارت‌زایی سوسک برگ‌خوار غلات Oulema melanopus (L.) (Coleoptera: Chrysomelidae) در مزارع گندم

نوع مقاله: علمی پژوهشی-فارسی

نویسنده

استادیار مرکز تحقیقات کشاورزی و منابع طبیعی مازندران

چکیده

لاروهای سوسک برگ­خوار غلات Oulema melanopus با تغذیه از برگ پرچم گندم موجب خسارت می­ گردند. این تحقیق با هدف بررسی امکان خسارت ­زایی این آفت روی گندم در سه مزرعه­ استان مازندران واقع در نکا (ایستگاه بایع کلا)، ساری (ایستگاه دشت ناز) و جویبار (ایستگاه پهناب)  در طی سال های 1392 و 1393 به اجرا در آمد. در هر مزرعه 10 نقطه تعیین و هم­زمان با اتمام فعالیت تغذیه­ ای لاروها، از هر نقطه 10 ساقه­ ی آفت­ زده و 10 ساقه­ ی سالم به‏ طور تصادفی انتخاب و شماره­ گذاری گردیدند.از برگ پرچم ساقه­ های آفت زده عکس تهیه شد و با استفاده از نرم افزار UTHSCSA ImageTool for Windows Version 3 شاخص خوردگی سطح برگ پرچم در تصویر نمونه­ ها در 4 رده (10٪>، 10-20، 20-40 و 40٪<) گروه ­بندی شدند. در فصل برداشت، خوشه ساقه­ های علامت‌گذاری شده جمع آوری و تعداد دانه و وزن دانه­ ی موجود در هر خوشه و وزن هزار دانه اندازه­ گیری گردید. نتایج نشان داد که فعالیت تغذیه ای لاروها می­ تواند بر وزن و تعداد دانه در هر خوشه و وزن هزار دانه تاثیر منفی گذاشته و با افزایش درصد خوردگی سطح برگ پرچم، وزن دانه و تعداد دانه در خوشه کاهش یافت. در رده 40٪< خوردگی برگ پرچم، کاهش وزن دانه، تعداد دانه و وزن هزاردانه در گیاهان خسارت دیده در مقایسه با گیاهان سالم در سال 1392 به ترتیب 58/42%، 86/25% و 76/32% و در سال 1393 به ترتیب 42/32%, 59/15% و 82/19% بود. ولی از آن­جائی­که شاخص خوردگی عموماً در رده های کمتر از 10٪ و 10-20٪ قرار داشته و بندرت به رده بیش از 40٪ رسید، و همچنین تعداد ساقه های با برگ پرچم آفت زده در واحد سطح پایین بود، خسارت­ زایی این آفت در مناطق مورد آزمایش پایین تا متوسط بود.   

کلیدواژه‌ها


عنوان مقاله [English]

Investigating the damage caused by Oulema melanopus (L.) (Coleoptera: Chrysomelidae) in wheat fields

نویسنده [English]

  • H. Barari
Assistant Professor, Agricultural and Natural Resources Research Centre of Mazandaran
چکیده [English]

Background and Objectives
Cereal leaf beetle, Oulema melanopus (L.) (Coleoptera: Chrysomelidae), is an important world-wide pest of wheat and barley. Adults and larvae feed on the upper side of leaves and chew long strips of tissue between the leaf veins especially on flag leaf, which can reduce grain yield. However, the greater damage is usually caused by feeding activity of larvae rather than adults. This paper presents the results of an investigation on the damage caused by this pest in wheat fields.
Materials and Methods
This study was carried out in three wheat (Line: N8019) fields located at Neka, Sari, and Joybar, in Mazandaran province, Iran. Occurrence and activity of the pest in the fields was monitored weekly from mid-February until mid-May during 2013 and 2014. Coinciding with the end of larval feeding-activity (early May), 10 spots were selected in each field, and 10 beetle-infested wheat stems (showing pest damage symptoms on flag leaf surface) and 10 intact stems (without damage symptoms) in each spot were randomly selected and labeled. The flag leaves of infested stems were photographed and infestation rates (% leaf surface damage) were assessed and categorized in four groups (<10%; 10-20%; 20-40%; >40%) using UTHSCSA image tool for windows version 3. At harvest time, the spikes of all labeled stems (infested and intact) were separately collected and grain weight and grain number per spike as well as 1000-kernel weight was measured. The relationship between percentage of flag leaf damage and yield (grain number and grain weight per spike) and 1000-kernel weight was calculated using regression analysis.
Results
Overwintered adult beetles were observed in the fields from early March, with a peak activity occurring at mid-March. Larval feeding activity started during late March and continued until early May. In both sampling years, the highest grain weight loss and number of grains per spike, and 1000-weight loss were observed in the >40% of infestation rate. Grain weight loss, number of grains reduction per spike, and 1000-kernel weight loss in the >40% infestation rate were 42.58%, 25.86% and 32.76% in 2013 and 32.42%, 15.59% and 19.82% in 2014, respectively.
Discussion
Results showed that the infestation rate of flag leaves can negatively affect grain weight per spike and 1000-kernel weight. With increasing percentage of flag leaf infestation, grain weight and grain number per spike, and yield decreased. However, in this study the infestation rates of flag leaves were mostly <10% or 10-20% and rarely reached >40% rate. During two-year sampling, only 10% out of 566 beetle-infested stems showed more than 40% leaf surface damage. In contrast, 46% and 62.3% of collected samples in 2013 and 2014, had less than 20% flag leaf surface damage. Therefore, the probability of severe damage caused by O. melanopus was low to moderate in the study sites.

کلیدواژه‌ها [English]

  • Cereal leaf beetle
  • damage
  • Mazandaran Province
  • Oulema melanopus
  • wheat
Asadeh, Gh. A., Mosadegh M. S., Soleymannezhadian, E., and Seraj, A. A. 2009.Population, spatial distribution and biology of cereal leaf beetle, Oulema melanopus Col.: Chrysomelidae, in winter wheat fields of Gorgan.Journal of Plant Production, 16(1): 165-180.
Battenfield, S. L., Wellso, S. G., and Haynes, D. L. 1982.  Bibliography of the cereal leaf beetle, Oulema melanopus (L.) (Coleoptera: Chrysomelidae). Bulletin of Entomological Society of America, 28: 291-302.
Gallun, R. L., Everly, R. T., and yamazaki, W. T.  1967. Yield and milling quality of Monon wheat damaged by feeding of cereal leaf beetle. Journal of Economic Entomology,  60(2): 356-359.
Hodgson,  E. W., and Evans, E. W.  2007. Cereal leaf beetle. Utah Pest Fact Sheet. Utah State University Extension. P. 4.
Ihrig, R. A., Herbert, D. A., Vanduun, J. W., and Bradley, J. R.  2001. Relationship between cereal leaf beetle egg and fourth-instar populations and impact of fourth-instar defoliation of winter wheat yields in North Carolina and Virginia. Journal of Economic Entomology, 33 (3): 258-264.
Kher, S. V., Dosdall, L. M., and Cárcamo, H. A. 2011. The cereal leaf beetle: biology, distribution and prospects for control. Prairie Soils & Crops Journal, 4: 32-41.
Kostov, K. 2001. Breeding wheat lines for host-plant resistance to cereal leaf beetle by using the cross mutation method. Bulgarian Journal of Agricultural Science, 7: 7-14.
Livia, C. 2006. Diversity and economic importance of the leaf beetles (Coleoptera, Chrysomelidae) in the republic of Moldova. Bulletin USAMV-CN, 62: 184-187.
Naeim, A. 1993. Investigation on cereal leaf beetle, Oulema melanopus, and its control methods in Isfahan. Journal of Plant Pests and Diseases, 51(1&2): 29-42.
Nori Ghanbolani, Gh. 1995. Methods of estimating the amount of pest damage to agricultural field crops. Pyshtaz Elm Publication, Tabriz (in Farsi).
Olfort, O., Weiss, R. M., Woods, S., Philip, H., and Dosdall, L. 2004. Potential distribution and relative abundance of an invasive cereal crop pest, Oulema melanopus (Coleptera: Chrysomelidae), in Canada. The Canadian Entomologist, 136:277-287.
Philips, C. R., Herbert, D. A., Kuhar, T. P., Reisieg, D. D., Thomson, W. E., and Mallone, S. 2011. Fifty years of cereal leaf beetle in the U.S.: an update on its biology, management and current research. Journal of Integrated Pest Management, 2(2): 1-5.
Rajabi, Gh., and Behrozin, M. 2007. Pests and diseases of wheat fields in Iran. Nashr-e-Amozesh-e- Keshavarzi Publication, Tehran (in Farsi).
Rao, S., Quebbeman, B., and Walenta D. 2004. Host range of cereal leaf beetle. In Young, W. D. (Ed), Seed Production Research, Oregon State University Ext/CrS, 123: 50-51.
Rouag, N., Mekhlouf, A., and Makhlouf, M. 2012. Evaluation of infestation by cereal leaf beetles (Oulema spp.) on six varieties of durum wheat (Triticum durum Desf.) seedlings in arid conditions of Setif, Algeria. Agriculture and Biology Journal of North America, 3(12): 525-528.
Royce, L. A. 2000. Cereal leaf beetle. Publication EM 8762. Extension Service, Oregon state University, Oregon. Available: http://extension.oregonstate.edu/ atalog/html/em/ em 8762, Accessed 20 February, 2010.
Seyedi Sahebari, F. 2007. Investigation on life cycle of cereal leaf beetle, Oulema melanopus on wheat in fiels and laboratory conditions. Research and development in Agriculture and Horticulture, 76: 142-147. (in Farsi with English abstract).
Seyedi Sahebari, F., Talebi Chaychi, P., and Malaki Milani, H. 2000. Investigation on cereal leaf beetle, Oulema melanopus (Col. Chrysomelidae) on wheat. Proceedings of 14th Iranian Plant Protection Congress, Esfahan, Iran. P. 14.
Shade R. E., Hansen, H. L., and Wilson, M. C.  1970. A partial life table of the cereal leaf beetle, Oulema melanopus, in northern Indiana. Annals of the Entomological Society of America, 63:52-59.
Sokolov, I. M. 1999. The effects of cereal leaf beetle Oulema melanopus (L.) (Coleoptera: Chrysomelidae) larval injuries on the yield of winter wheat heads [in Russian]. Entomological Review, 78(2):307-315.
Talebi Chaychi, P., Seyedi Sahebari, F., and Malaki Milani, H. 1999. Investigation on life cycle of cereal leaf beetle, Oulema melanopus (Col. Chrysomelidae) on wheat in fiels conditions. Agricultural Knowledge Journal, 9(3):1-15.
Walczak, F. 2005. Determination of developmental periods of leaf beetle (Oulema spp.) for short-term forecasting. Journal of Plant Protection Research, 45(3): 145-153.
Webster, J. A. and Smith, D.H. 1983. Cereal leaf beetle (Oulema melanopus (L.)) population densities and winter wheat yields. Crop Protection, 2(4): 431-436.
Wellso, S. G., Connin, R. V., and Hoxie, R. P. 1973. Oviposition and orientation of cereal leaf beetle. Annals of the Entomological Society of America, 66: 79-83.