جستجوی مقالات مرتبط با کلیدواژه "strip-intercropping" در نشریات گروه "کشاورزی"

  The European corn borer, Ostrinia nubilalis (Hübner), is an important pest of corn in Iran. Intercropping systems has been proposed as one approach that can be used for reducing pest density and improving biodiversity of natural enemies and crop yield. Therefore, the present research assessed the densities of immature stages of O. nubilalis, biodiversity of its predators, and parasitism rates of immature stages in experimental plots where corn was grown either as monoculture or strip-intercropped with sunflower. We also evaluated the effect of the intercropping systems with natural infestation of O. nubilalis on corn yield. In this research, the influence of five strip-intercropping systems of corn (C) and sunflower (S)including 2C: 2S, 4C: 2S, 8C: 2S, 4C: 4S, and 2C: 4S along with corn monoculture was studied on density of imaginal stages of O. nubilalis, its natural enemies biodiversity, the percentage of parasitized eggs and larvae, and the grain yield of corn and the percentage of grain yield loss in an experimental field in Ardabil region in 2016 and 2017. These experimets were conducted in a randomized block design with four replicates. The densities of imaginal stages (eggs, larvae and pupae) of O. nubilalis in intercrops were significantly lower than corn monoculture. Among the natural enemies of this moth, Orius niger (Wolff), Lydella thompsoni Herting, Bracon hebetor Say and Trichogramma brassicae Bezdenko had the high relative abundance in the tested cropping systems. The Shannon diversity index (H') in intercrops was significantly greater than in corn monoculture. The calculated values of Morisita–Horn index for the predator’s species composition between intercrops were CMH ≥ 0.946 in 2016 and CMH ≥ 0.934 in 2017. In both years, the percentage of parasitized eggs and larvae of O. nubilalis in intercrops was significantly higher than in corn monoculture. The highest grain yield of corn and the lowest percentage of grain yield loss of corn were found in 8C: 2S intercrop. Based on the resource concentration hypothesis, the lower density of O. nubilalis and the lower percentage of infested plants in the intercropping systems of corn and sunflower could be demonstrated by overlapping of the secreted volatile compounds of two crops that caused disruption in the host finding. Moreover, based on the enemies hypothesis, the higher attraction and conservation of predators and parasitoids in intercrops caused lower density of O. nubilalis than in corn monoculture. In this study, the competition for nutriants between corn and sunflower was also reduced with increasing of the corn rows between the sunflower rows; the percentage of grain yield loss of corn was reduced in 8C: 2S copmpared to other intercrops. Therefore, it could be concluded that 8C: 2S intercrop is the most suitable intercropping system for use in integrated management of O. nubilalis in corn fields

In this research, the influence of intercropping systems (including three, six and nine rows of green bean, Phaseolous vulgaris L. with alternate three rows of clover, Trifolium resupinatum L.) and monoculture of green bean on biodiversity of the onion thrips, Thrips tabaci Lindeman and the proportion of predators/prey density were studied in an experimental field in the Ardabil during 2015 and 2016 years. In this study, 21 species of onion thrips predator were collected and identified that among them, the predator species Aeolothrips intermedius Bagnalland and Orius niger (Wolff) had the highest relative abundance in each of cropping systems. The Shannon diversity index (H) in each of the three intercrops was significantly greater than in green bean monoculture. The values of Morisita–Horn index (CMH) between green bean monoculture and each of the three intercrops (CMH ≤ 0.85) were lower in comparison with the values of this index among the three intercrops (CMH ≥ 0.94). In two years, the proportion of predators/prey and the density of the onion thrips predators especially two dominant species A. intermedius and O. niger in each of the three intercrops were significantly higher than in green bean monoculture. Therefore, it can be concluded that strip-intercropping of green bean with clover caused higher biodiversity of the onion thrips predators and reduced the density of T. tabaci. Application of the mentioned strip-intercropping systems in the green bean fields as one of the important components in the integrated management of the onion thrips is recommended.

The European corn worm, Ostrinia nubilalis (Hübner) is an important pest of corn in Iran. In this research, the influence of corn monoculture and also, three strip-intercropping systems including three, six and nin rows of corn with three rows of clover were evaluated on the natural enemies diversity of O. nubilalis, the proportion of predators/prey density and finally, the percentage of parasitized eggs and larvae in experimental fields in Ardabil region in 2014 and 2015. In this study, eight predator species, five larval parasitoid species and one egg parasitoid species were collected and identified which amongst them, Orius niger (Wolff), Lydella thompsoni Herting, Bracon hebetor Say and Trichogramma brassicae Bezdenko had the high relative abundance in the tested cropping systems. The Shannon diversity index (H) in each of the three intercrops was significantly greater than in corn monoculture. The values of Morisita–Horn index (CMH) between corn monoculture and each of the three intercrops (CMH ≤ 0.893) were lower in comparision with the values of this index among the three intercrops (CMH ≥ 0.977). In two years, the proportion of predators/prey, and the percentage of parasitized eggs and larvae of O. nubilalis in each of the three intercrops were significantly higher than in corn monoculture. Implementation of these cultivation systems in the corn fields is an important step in the management of O. nubilalis.

Intercropping is a sustainable practice used in many developed and developing countries and an essential element of agricultural sustainability. Intercropping is simultaneous growing of two or more crops during a given season on same location. Such a method enables the utilization of common limiting resources more efficiently than the species grown separately. Using two species with different growth habits and the least competitive characteristics in intercropping, increases the efficiency of resources (light, water and nutrients) and absorption in comparison with the sole cropping (Fernandez-Aparicio et al., 2008). The study of intercropping of borage (Borago officinalis L.) and bean (Phaseolus vulgaris L.) showed that the highest economic yield was achieved in monoculture and the lowest economic yield was obtained in four rows of borage plus four rows of bean, but the maximum land equivalent ratio was calculated in 2:2 intercropping. The aim of current study was to determine the best combination and efficiency of resource utilization in intercropping of additive series of chickpea and black cumin. The results were compared to respective monoculture and the advantages of intercropping was determined. The effects of planting different ratios of two crops on yield and yield components of sesame (Sesamum indicum L.) and chickpea (Cicer arietinum L.) was also investigated. The results of intercropping of additive series showed that the highest grain and biological yield of chickpea were obtained through monoculture and the lowest grain and biological yield of chickpea achieved by planting ratio of 100% sesame and 10% chickpea.
To evaluate the effects of different intercropping arrangements of sunflower, sesame and red bean on growth characteristics, yield components and yield, a field experiment was conducted at Agricultural Research Station of Ferdowsi University of Mashhad, Iran during two growing seasons of 2009-2010 and 2010-2011. For this purpose a randomized complete block design with six treatments and four replications was used. Treatments were: (A) one row for each special intercropping, (B) row intercropping (two rows for each species), (C) strip intercropping (four rows for each species) and (D) sole crop of sunflower, (E) sole crop of red bean and (F) sole crop of sesame (twelve rows for each species).
Land equivalent ratio (LER)
Land equivalent ratio of sunflower, sesame and red bean was calculated (Sullivan, 2003) as:LER= Y1/L1捯
Where Y1 and Y2 represent sunflower, sesame and red bean yield in intercropping and L1 and I2 represent sunflower, sesame and red bean yield in mono-culture, respectively.
Statistical analyses: SAS ver. 9.1 and MSTAT-C softwares were used for statistical analysis. To compare the means, Duncan's multiple range test at 5% probability level was used.
Results showed that the growth characteristics, yield and yield components of sunflower, sesame and red bean were significantly (p≤0.01) affected by different intercropping arrangements. There was a decreasing trend in these parameters from intercropped towards the sole crop for sesame and red bean and an increasing trend for sunflower. The highest biological and economic yield of sesame (4751 and 2207 kg ha-1, respectively) and red bean (5701 and 2719 kg ha-1, respectively) were observed in monoculture. There was a decreasing trend in land equivalent ratio (LER) from row intercropped toward, strip cropping. Maximum and minimum LER were observed in A and C with 1.38 and 1.02, respectively.
According to the results, intercropping of sunflower, sesame and red bean can be beneficial in terms of ecological management. In general the arrangements of sunflower, sesame and red bean could be recommended for achieving high yield in sunflower in this region.

Intercropping is known to improve the utilizing resources and increasing yield and yield stability as compare with monoculture. To evaluate wheat-chickpea intercropping، an experiment in factorial split plot based on randomized complete block design with three replications was carried out in Dryland Agricultural Research Institute، Sararoud، Kermanshah، Iran، during two years (2008-10). Two factors، N fertilizer in three levels (1. No fertilizer; 2. 60 kg. ha-1 urea for wheat and 20 kg. ha-1 for chickpea and 3. Nitragin as a biofertilizer + 30 kg. ha-1 urea for wheat and no urea for chickpea) and weed control in two levels (no weeding and weeding) were placed as factorial in main plots. In the sub-plots were also placed ten intercropping patterns including: 1. Wheat monoculture، 2. Chickpea monoculture، 3. Mixed-row intercropping with 1:1 ratio of wheat: chickpea، 4. Mixed-row intercropping with 2:1 ratio of wheat: chickpea، 5. Row intercropping with 1:1 ratio of wheat: chickpea، 6. Strip intercropping with 2:5: 1:5 ratio of chickpea: wheat: chickpea: wheat، 7. Strip intercropping with 2:7 ratio of chickpea: wheat، 8. Strip intercropping with 7:2 ratio of chickpea: wheat، 9. Strip intercropping with 4:9 ratio of chickpea: wheat and 10. Strip intercropping with 9:4 ratio of chickpea: wheat. Results showed that number of grain per spike، number of spike per m2، grain yield، plant height، biological yield and harvest index of wheat were affected by inter-specific competition (cropping pattern)، year and their interaction effect. Wheat had higher competition ability to uptake and use the resource than chickpea. Strip intercropping patterns with lower width of the wheat strip and more width of chickpea strip (patterns 8 and 10) and row intercropping (pattern 5) were better than the wheat monoculture in most studied traits like plant height in first year، biological and grain yield، harvest index and light absorption. The row intercropping in second year reduced weed biomass in chickpea which not only was superior to monoculture، but it can be used as an approach to weed control in chickpea

To evaluate the effects of wheat (Triticum aestivum) and oilseed rape (Brassica napus) strip intercropping on yield components, seed and biological yields of oilseed rape, field experiments were carried out as factorial based on randomized complete block design with three replications at Research Farm of Tabriz University, Tabriz, Iran during 2010-2012 cropping seasons. The first factor consisted of four types of wheat and oilseed rape cropping system, sole crop of oilseed rape (A1),: strip intercropping with 8:3 (A2), 12:4 (A3) and 16:5 (A4) of wheat and oilseed rape rows, respectively and the other factor consisted of two fertilizer levels, B1: 100% chemical fertilizers (urea and triple superphosphate) and B2: 50% chemical fertilizers biofertilizers (Nitrazhin and Barvar2). The results showed that strip intercropping of wheat- oilseed rape resulted in significant increase in yield components, seed yield per occupied unit area and biological yield per occupied unit area of oilseed rape as compared with mono-cropping. The number of silique per plant in intercropping systems was significantly higher than that of mono-cropping. The highest seed yield was obtained in the 16:5 rows of wheat-oilseed rape with 343.76 g.m-2 and the lowest mean was observed in mono-cropping of oilseed rape with 260.21 g.m-2. Biological yield per occupied unit area and seed yield per intercropped unit area in B1 were significantly greater than that of B2, but this treatment had no significant effect on the other traits. Because, B1 and B2 had no significant difference in seed yield per occupied unit area and due to the importance of reduction in chemical fertilizers consumption and food and environmental health care, strip intercropping of wheat-oilseed rape under 50% chemical fertilizers biofertilizers can be recommended as a suitable cultural method.

In order to evaluate the comparison of different intercropping patterns of cumin (Cuminum cyminum L.) with lentil (Lens culinaris L.) in double crop، a field experiment was conducted based on a randomized complete block design with three replications and eight treatment at the farm located in West Azerbaijan province - city Nagadeh، Iran during growing reason of 2011-2012. Treatments included intra- row intercropping (50% cumin + 50% lentil)، row intercropping (one row of lentil + one row of cumin) and strip intercropping (two rows of lentil + one rows of cumin، three rows of lentil + one rows of cumin، four rows of lentil + four two of cumin، six rows of lentil + two rows of cumin and pure lentil and cumin. Intercropping patterns had significant effect on all of mentioned traits. Results showed that the highest and the lowest economic yield of lentil were achieved in monoculture with 600 and 1600 kg. ha-1and six rows of lentil + two rows of cumin with 273 and 676 kg. ha-1، respectively. Grain yield and biological yield were no significant differences at monoculture with row intercropping and intra- row intercropping. But with increasing strip widths of grain yield and biological yield decreased by 50 and 54 %، respectively. The essential oil percentage of all treatments was higher than monoculture. The highest essential oil yield was obtained of intra- row intercropping (20 kg. ha-1). Results indicated that maximum (1. 8) and minimum (0. 94) LER values were obtained of row intercropping and strip intercropping (six rows of lentil + two rows of cumin)، respectively. By changing row intercropping patterns to strip intercropping، LER was decreased due to complementary and facilitative effects in intercropping.

To evaluate the effects of rows of maize-pintobean, maize-soybean planted in strip intercropping and their sole croppings, an experiment using randomized complete block design with three replication, was conducted for two consecutive years at the Agricultural Research Center of Islamic Azad University, Tabriz branch. Treatments were: A (intercropping of maize-pintobean, one row of each, B (intercropping of maize-pintobean, two rows of each), C (intercropping of maize-pintobean, three rows of each), D (intercropping of maize-soybean, two rows of each), E (intercropping of maize-soybean, two rows of each), F (intercropping of maize-soybean, three rows of each), G(sole cropping of maize), H (sole cropping of pintobean) and I (sole cropping of soybean). Experimental results showed that maize produced, in both years, highest (17818 kg/ha) using treatment D and lowest (15509 kg/ha) yields in treatment G. This indicates that maize produced higher yield in intercropping than sole cropping. Maize, also, produced highest yield in treatment D and lowest in treatment F. Pintobean had highest yield (2498 kg/ha) in treatment H and lowest (2073 kg/ha) in treatment A. Soybean, on the other hand, produced highest yield (4794 kg/ha) in treatment I and also lowest (3257 kg/ha) in treatment D. A a whole, it may be concluded that pintobean and soybean produce higher yield in sole cropping as compared to intercroppings.