Our research has been done in order to find out the effects of soil SOLARIZATION on population of prostigmatic mites, in Fars Science and Research, Fars Province, during the years 2010-2011. We prepared a land with the area of 120 m2 in the above location. The block was divided to 3 parts of 5×8 m. The first part was covered by a plastic, the second part was covered by a plastic but the soil was mixed with manure. The third part was used as control. Samples were taken randomly from the depths of 5, 10 and 15 cm every other day. Totally 1215 prostigmatic mites were collected from 108 soil samples. These mites belonged to 6 families of Cunaxidae, Bdellidae, Cheyletidae, Tetranychidae, Stigmaeidae and Tenuipalpidae. In this research Tetranychid mites had the most and Tenuipalpid mites had the least population in different depths of the soil. Our results indicated a significant reduction in Prostigmatic mites population in both plastic covered treatment and plastic covered with manure in compare to control.

Soil SOLARIZATION is a simple, safe, and effective method which controls soil born pests and seeds of many conventional noxious weeds. An experiment was conducted to evaluate the effect of soil SOLARIZATION on weed seed bank in Mashhad, Iran during summer 2007. A factorial experiment based on randomized complete block design with two factors, SOLARIZATION with Clear and black polyethylene sheets and non-solarized control, and identified species in seed bank, with three replications was used. In order to study effects of soil organic matter, water content and pH on weed seed bank, soil sample were taken and analysed in all plots. Eleven weed species was identified by studying weed seed bank which were mainly annual broad-leaves species. Results indicated that soil SOLARIZATION with clear polyethylene sheets reduced weed seed bank significantly, but there was no difference between control and black polyethylene sheets. Soil water content was significantly higher in soil covered with polyethylene sheets, but soil pH and total organic matter remained unchanged. There was a significant negative correlation between weed seed density and water content.

Some of the field crops are severely affected by the Fusarium foot and root-rot in the west of Iran, Hamadan. Pathogenic Fusarium species are potentially severe destructive diseases and could be a major limiting factor for the cereals and potato production in this province. The purpose of this study was to determine the possible effect of soil SOLARIZATION on the population dynamics of Fusarium spp. The propagules under Hamadan climatic conditions. Pretarping irrigation to achieve the field capacity was carried out prior to the various treatments including the black and transparent polyethylene plastic sheets. The experiment was performed in a completely randomized block design with three replicates, in a naturally infested soil. After three, five and eight weeks, soil samples were collected from different soil depths in appropriate plots. The propagule numbers of Fusaria were counted through dilution plate method using selective Nash & Synder and PDA media. The results indicated that the propagules of Fusarium in treated soils (five and eight weeks treatments) were significantly decreased as compared with the three week treated and untreated control plots. Better results obtained with the transparent sheets after eight weeks, followed by treatments with five weeks of mulching. Accordingly, the hydrothermal control of the Fusarium foot and the root-rot disease seem to be effective under the cool and temperate area of Hamadan.

Introduction: Weeds are important components of agricultural ecosystems that compete with agricultural crops to capture resources and caused irreparable damage to the crops. By producing herbicides, a significant change was created in the management of weeds. But now days some new problems such as resistance of weeds to herbicides, loss of useful species and environmental pollutions have forced farmers to employ non-chemical weed management methods. An important non-chemical method for seed control of weeds is soil SOLARIZATION, which has been used as a way for controlling weeds, pests and diseases. South Khorasan enjoys plenty of solar radiation during the summer which can be used as a useful tool for weed control. Materials And Methods: To evaluate the effect of soil SOLARIZATION on downy brome )Bromus tectorum L. ( control, an experiment was conducted at the research farm of College of Agriculture, University of Birjand during the summer of 2010. The factorial experiment was performed as a randomized complete block design with three factors including the number of clear plastic layers (uncovered as the control, one-layer and two– layer plastic sheets(, duration of coverage (15, 30 and 45 days) and seed burial depth (0, 5, 10 and 15 cm) with three replications. Seeds were buried at different soil depths in the field and experimental plots were covered with the corresponding plastic layers. The seed samples alternatively were pulled out of different depths of soil and transported to the research laboratory. The seeds which were germinated in the field were counted, and the rest of them were incubated in a germinator set at 25/15° Cfor day/night. During the germination period, some index such as; germination rate, percentage of decayed and germinated seeds were measured. Tetrazolium test was used to examine the viability of not germinated seeds. Results And Discussion: Results showed that SOLARIZATION significantly increased soil temperature (as much as 6. 3 to 15. 1° C) compared to the control. The percentage of germination in the field decreased by increasing the layers of plastic coverage, as well asby increasing burial depths. The maximum percentage of decayed seeds were observed at two-layer plastic, one-layer plastic and control treatments, respectively. The percentage of decayed seeds increased by increasing SOLARIZATION duration and it decreased by increasing burial depth. During the whole period of SOLARIZATION, the lowest decay percentage was observed in the control treatment, while the greatest corresponding values were obtained from the seeds placed under oneand two-layer plastic sheets, indicating that accumulated temperatures under these sheets caused an increased decay percentage. At the soil surface and 5 cm burial depth, none of the downy brome seeds in 1-and 2-layer plastic sheet could germinate in the laboratory. It seems that the high temperatures generated by soil SOLARIZATION have destroyed downy brome seeds under plastic covered treatments. A soil SOLARIZATION period of 15 days was sufficient for destroying the seeds on the soil surface and those buried at 5 cm depth, while a SOLARIZATION period of 45 days was required to destroy the seeds buried at 10 and 15 cm depths. Seeds that had been exposed to high temperatures caused by SOLARIZATION for a longer period, had a lower germination rate. The greatest germination rate was observed in the control treatment and on the soil surface. The results of Tetrazolium test showed that all none germinated downy brome seeds which were subjected to Tetrazolium test had lost their viability, or in other words, were decayed. After finishing the SOLARIZATION experiment we found that the concentration of sodium, calcium, and magnesium and sodium uptake ratio and soil pH decreased decreased under solarized plots. Moreover, electrical conductivity (EC) increased. Conclusion: Overall, the results showed that SOLARIZATION reduced the downy brome seed germinability and ultimately led to an effective method to control of this weed. It appears that SOLARIZATION can be used as a non-chemical method for downy brome control especially in arid regions of the country. According to the results of this study, covering the soil with two-layer plastic sheet was the most effective and the best method of SOLARIZATION.

In order to study the effects of soil SOLARIZATION on weed control, an experiment with factorial arrangement in a randomized complete block design with four replications was conducted in a fallow farm in Daregaz in 2008. Factors included SOLARIZATION duration (0, 2, 4 and 6 weeks) and soil moisture content (dry and moist). Soil seed bank was sampled (in two depth, 0-10 and 10-20 cm) prior to the experiment and immediately after applying treatments, and germination percentage of weed species were determined. Results of this study showed that seed germination percentage in 10 cm soil depth was influenced by soil moisture and SOLARIZATION and their interactions, while in 20 cm soil depth only SOLARIZATION period affected the weed seed germination. Germination percentage in moist soil was less than that in dry soil. Seed germination percentage declined more by increasing SOLARIZATION duration, so that the greatest decline was obtained after 6 weeks SOLARIZATION. SOLARIZATION decreased germination percentage in moist soil more than that in dry soil. Overall, the results of this experiment indicated that SOLARIZATION of moist soil for 6 weeks was the most effective treatment in controlling common lambsquatres (Chenopodium album), common purslane (Portulaca oleracea), redroot pigweed (Amaranthus retroflexus), and wild mustard (Sinapis arvensis), while SOLARIZATION of dry soil for 2 weeks was the least effective treatment for weed control.

Combining effects of soil SOLARIZATION and grafting on soilborne pathogens, plant height and yield in cucumber were compared in a greenhouse of Bati Akdeniz Agricultural Research Institute located in Antalya in 2008 fall season. The experiment was set in split plot design containing; 1, 2, 4 and 5 months soil SOLARIZATION (MSS), and non-solarized control plots (NSC) on which grafted Maximus F1+ Bergama F1 and non-grafted Bergama F1 were grown. Almost all of plants grown in nonsolarized plots were infected with root-knot nematodes with severe root damages; however, only a few plants were affected by this nematode in 4 and 5 months solarized plots with very slight root galls. No resistance to root-knot nematodes was observed in both grafted and non-grafted plants. Almost half of the plants grown on non-solarized control plots were infected with Fusarium oxysporum f. sp. cucumerinum with relatively slight disease symptoms. In conclusion, combining SOLARIZATION with grafting significantly promoted early flowering time, plant vigor, early and total yields and reduced nematode and fusarium wilt damages in this study.

To study the effects of soil SOLARIZATION, barley straw mulch and hand weeding on weed seedbank, a field experiment was conducted at Research Farm of College of Agriculture, Ferdowsi University of Mashhad during 2007-2008 growing season. This experiment was based on a randomized complete block arranged as a split-split plot design with three replications. Clear and black polyethylene, and non-solarized control were arranged on main plots. A different straw mulch rates (0, 300 and 600 gm-2), and weeding treatment were in the sub-plots and sub-sub plots, respectively. A total of 19 weed species was recorded in all treatments which were mainly annual broad leave species. Results indicated that SOLARIZATION with clear sheets had 1.8 times less seed density than the control plots. Application of straw mulch decreased weed seed population. Also, hand weeding was effective in reducing weed seeds. Weed seedbank density in no-weeding plots was 3 times greater than weed control plots.The interaction between soil SOLARIZATION, straw mulch and weeding on seedbank size was significant. The lowest number of weed seeds was observed in clear polyethylene, 300 gm-2 straw mulch and weeding.

Effects of soil SOLARIZATION, fumigation with metam sodium, cow manure and their combinations on fusarium wilt of carnation, were investigated using randomized complete block design in three replications in greenhouse condition under artificial inoculation at Mahallat. Region In this study, population density ofFusarium oxysporum was reduced considerably in upper 10cm layer of soil in SOLARIZATION, fumigation, and combination SOLARIZATION with cow manure and SOLARIZATION with metam sodium treatments. During the 9 months after treatments, the amount of fusarium decreased in SOLARIZATION and metam sodium treatments but increased in combination of salarization and metam sodium and stabilized in combination of SOLARIZATION and cow manure. The amount of wilt in carnation at end growth season reached to minimum in SOLARIZATION, metam sodium and combination of SOLARIZATION and cow manure treatments. Relate of the disease was resemble in combination treatments and fumigation retarded the disease considerably but had not significant different with SOLARIZATION. Combination of SOLARIZATION and cow manure had highest amount of flower in plant and vase life. The other quality and quantity properties have not significant different in treatments. In consider to best effect of combination of SOLARIZATION with cow manure on quality properties of carnation and decreasing of infected plants, this treatment could be a suitable alternative for pre-plant treatment for control of this disease.

Sugar beet cyst nematode (Heterodera schachtii Schmidt) is transferred to sugar factories along with the sugar beet root and its surrounding soil, so called depot soil. Because of high infestation and the possible transfer and distribution of this soil, disinfestations of the depot soil should be taken into considerations. In order to assess the possibility for disinfestations of the depot soils in Esfahan sugar factory, an experiment with four treatments including, SOLARIZATION (using transparent polyethylene sheet of 30m thickness), undecomposed farm manure, the combination of SOLARIZATION and farm manure and control (no operations) were compared in three replications at four various depths (0-15, 15-30, 30-45 and 45-60 cm) for two continuous years. Before and after the experiment, the populations of eggs and second stage juveniles were measured. The results showed that the combination integrations of soil SOLARIZATION and farm manure had the highest effect and significantly reduced the nematode population as compared with the other treatments, especially at the depth of 0-15 cm. The population reductions in the respective depths in the combination of SOLARIZATION and farm manure were 99.85, 99.28, 98.5 and 96.18 percent and those in control were 18.41, 36.14, 52.97 and 49.06 respectively. The farm manure and SOLARIZATION treatments were not significantly different, but they were different from the control.

Saffron is the most expensive agricultural product and like other products, is affected by some limiting factors, including soil pests such as bulb mite Rhizoglyphus robini Claparede (Acari: Acaridae). Due to its polyphagous habit, it remains in the soil for a long time and is one of the most important pests of saffron. To determine the effect of non-chemical management factors including soil SOLARIZATION days, fertilization and year on the population of bulb mite and yield of saffron, a split-plot experiment based on a randomized complete block design in three replications was conducted between 2007 and 2011 in Gonabad, Iran. Fertilization (Cow manure) of zero, 20 and 40 t/ha as the main plots and soil SOLARIZATION of zero, 10, 20, 30 and 45 days as sub-plots were studied for four years. The results showed that simple and interaction effects of the three factors including year, fertilization and soil SOLARIZATION days on the population of bulb mite and saffron yield were significant. Simple linear regression was fitted between the population of bulb mite and saffron yield as well as multiple linear regression for population of bulb mite and saffron yield separately. The population of bulb mite increased during the experiment by increasing the two factors of the year and fertilization separately. Whereas, with increasing soil SOLARIZATION days, population of bulb mite decreased except for 10 days SOLARIZATION treatment and, unexpectedly, in 45 days of SOLARIZATION treatment, the population increased in the fourth year.