كليدواژه :
راندمان كنترل علف هرز , عملكرد علوفه , نسبت برابري زمين , نسبت رقابت , علف هرز گلرنگ وحشي , گياه جو
چكيده فارسي :
به منظور بررسي عملكرد كمي و كيفي علوفه در كشت مخلوط جو (Hordeum vulgare L.) و ماشك معمولي (Vicia sativa L.) آزمايشي در دانشكده كشاورزي دانشگاه لرستان در سال زراعي 93-1392 با 24 تيمار به صورت فاكتوريل 4×6 در قالب طرح پايه بلوك‌هاي كامل تصادفي انجام گرفت. كاشت مخلوط به صورت جايگزيني همزمان اجراء شد، فاكتور اول شامل شش سطح جزء كشت مخلوط، تك كشتي (كشت خالص) كاشت ماشك معمولي 100 درصد، 55-45 درصد (جو-ماشك)، 65-35 درصد، 55-45 درصد، 35-65 درصد و تك كشتي جو و فاكتور دوم شامل چهار سطح آلوده به علف¬هرز گلرنگ وحشي (Carthamus oxyacantha Bieb.): شاهد (عاري از علف‌هرز)، 10، 15 و 20 بوته در مترمربع بود، نتايج حاصل از آزمايش نشان داد به تناسب تغيير در وزن خشك برگ و ساقه دو گياه مورد آزمايش، عملكرد علوفه نيز تغيير يافت. در بين اجزاء مخلوط (نسبت‌هاي بذري بر اساس تراكم)، نقش تركيب 35-65 درصد در كاهش بيوماس گلرنگ وحشي مؤثرتر از ساير تركيب‌ها بود، از طرفي دو نسبت بذري 65-35 و تك كشتي ماشك، كمترين نقش را در كنترل علف هرز داشتند. همچنين نتيجه گرفته شد كه سهم ماشك معمولي در افزايش بهره¬برداري از منابع محيطي و سودمندي كشت مخلوط (LER) بيش از جو مي‌باشد، بنابراين كاهش سهم ماشك در سيستم مخلوط، علي رغم قدرت رقابتي اين گياه با علف هاي‌هرز منجر به كاهش LER اين گياه خواهد شد. از طرفي نسبت رقابت (CR) براي جزء مخلوط ماشك معمولي در مقايسه با جو در تمام تيمارها بزرگ تر از يك بود، بيشترين نسبت رقابت براي ماشك و جو معادل 64 / 2 و 83 / 1 بود كه به ترتيب از تركيب مكمل مخلوط 55-45-شاهد و 35-65-شاهد به دست آمد. بر اساس محاسبات صورت گرفته نشان داده شد كه سهم ماشك معمولي در راندمان كنترل علف هرز (WCE) گلرنگ وحشي، بيش از جو است، محاسبات نشان داد كه اين راندمان، توسط اجزاء مخلوط در تراكم 15 بوته گلرنگ وحشي در مترمربع، بيش از 10 و 20 بوته مي باشد. در ماشك معمولي و جو بيشترين عملكرد علوفه خشك در كشت مخلوط، به ترتيب از تركيب 35-65-15 درصد و 65-35-10 درصد برابر با 802 / 2 و 093 / 3 تن در هكتار به دست آمد.
چكيده لاتين :
Introduction
In agronomy, natural outlook has been expressed in different forms which stable agriculture is an example.
Stable agriculture is ascribed to the authentic management of agricultural resources, which in addition to
fulfilling the ever-changing needs of humans, maintains the health of environment and capacity of water and soil
resources. Application of herbicides, besides being costly, resulted in the selection of herbicide resistant weed
species and has become an environmental contamination factor. However, reduction of herbicide consumption is
one of the goals of modern agriculture, with several methods being suggested, including intercropping. In natural
conditions of production, environment conservation of weed existence requires cost. One of the important
preparations in weed control from the perspective of sustainable agriculture, is using intercropping system. The
aim of this study was to determine the role of crop diversity on weed and crop production based on the beneficial
effects of intercropping system than pure.
Materials and methods
In order to study effects of mixed and sole cropping of barley with common vetch on their biologic yield and
utilization indices, an experiment was conducted in Agricultural college of the University of Lorestan, during the
growing season of 2013-2014 with 24 treatments using the method of rows replacement series technique by the
randomized complete block design in a factorial arrangement with three replications. First factor included 6
levels of intercropping: sole cropping of common vetch (100%), 55-45 (Common vetch-barley), 35-65, 45-55,
65-35 and sole cropping of barley and second factor included 4 levels of weed wild safflower, control, 10, 15
and 20 plants per m2. In this experiment WCE, LER and CR were measured. The data were subjected to analysis
of variance (ANOVA) using Mstat-C computer software. Mean comparisons were performed using Duncan’s
multiple range test at two levels of significant 1% and 5%.
Results and discussion
There was significant difference between minimum and maximum dry weight of weeds, the results showed
that barley have important role in weed control wild safflower. Therefore, weed control efficiency in 15 plant in
m2 was higher than two 10 and 20 plant in m2. The lowest WCE (161.27%) was found at 15-35-65 treatment,
but, the highest WCE (51.99) was obtained from 15-65-35 (Wild safflower-common vetch-barley) treatment.
Computes showed that WCE, in 15 plants of wild safflower/m2, was more than 10 and 20 p/m2. The reduction in
weed population and biomass in intercropping systems with barley may be attributed to shading effect and
competition stress created by the canopy.
Thus, result showed that reduction rate of common vetch in intercropping, with bearing compatibility power
to weeds reduced LER. CR for common vetch intercropping component in comparison with barley in total
treatments was>1. The highest CR, for vetch obtained from treatment 45-55-control (2.64) and for barley from
seed ratio 65-35-control (1.83).
Conclusion
The results in this study showed various seed rate had noticeable effect on forage yield, LER and weed control. In this experiment changing seed rate in two tested plants (barly- commen vetch) changed the number
and weed species, as a result noticeable changing was created in their competitive power. Result showed that
seed rate (35% barley-65% common vetch) was better than other treatment, not only in use efficiency of
environment, but also it had more dry forage yield. Also, former seed rate had effective role in decreasing the
weed biomass. This important result was related to reduced light penetrate at the bottom of cover crop and
probably lack of competition in access to environmental resources was also affected. So using this seed density
for mentioned area is recommended for reducing weed competition and improving the quality and quantity of
dry forage.
Acknowledgments
The authors gratefully acknowledge the teachers of College of Agriculture of Lorestan University, for their
critical review of the manuscript.
