Manure application is one of the most important sources of WEED SEED for infestation farms and orchards. Temperature and moisture are two important factors influencing WEED SEED VIABILITY within manure. Therefore in order to study the effect of temperature, and duration of WEED SEED in manure on WEED SEED VIABILITY, a series of experiments were conducted at the laboratory of WEED sciences, Ferdowsi University of Mashhad; by using a Completely Randomized Design (CRD) with factorial arrangement and 3 replications. Treatments included different temperatures (25, 40, 50, 60, and 70°C); and duration of WEED SEED in manure (0.25, 0.5, 2, 3, 5, and 7 days); WEED species (redroot pigWEED, canarygrass, common lambsquarters, and Flix WEED); and manure (cattle manure or no manure).The results showed that SEEDs of all WEED species were killed by keeping at 50°C after 5 days, but SEEDs of common lambsquarters could survive at 60°C for 12 hours. Also high temperature shortened the mean germination time (MGT) of all species. There were significant differences among WEED SEED species with regard to temperature tolerance and duration of WEED SEEDs in manure, which may be related to SEED structural and physiological properties. In conclusion, SEEDs of common lambsquarters and flixWEED species showed the highest and least tolerance to temperature and durability in manure, respectively.

Adding fresh manure to cropland results in an increased WEED population ensued from SEEDs present in the manure. Composting process can reduce WEED SEED VIABILITY. In an experiment SEED VIABILITY of sixteen important WEED species in forage fields were studied during composting process. SEEDs enclosed within nylon mesh bags were buried into the two compost piles, at 0.5, 1 and 1.5 meters depths for 4 months in early summer in 2004. Two compost piles made from cow manure and one of them was covered by plastic sheets. SEED packets were removed monthly for 4 months to test SEED VIABILITY.The results showed a dependence between WEED SEED VIABILITY lost in compost and composting high temperature. Compost piles tended to have higher temperatures at 0.5 meter (60-70oC) than 1 and 1.5m at first and second months, then the temperature decreased. This is probably because the pile was better aerated at the depth of 0.5m. SEED VIABILITY loss was different for each species. Some of species showed about 100% VIABILITY loss after one month. WEED SEEDs lost their VIABILITY at the 0.5m depth having higher temperature compared to deeper layers. In the covered compost pile, SEED VIABILITY loss and temperature were lower than in uncovered compost pile. Almost all WEED species were killed after being placed for 2 months at 0.5m depth of uncovered compost piles in summer. However, only VIABILITY of Cuscuta monogyna, Goldbachia laevigata, Chenopodium album and Amaranthus retroflexus were decreased after 3 months. Chemical test showed that water content reduced after one month composting at three different depths. pH values varied between 7 to 8. Carbon to nitrogen ratio was between 15-20 after three months of composting at three above-mentioned depths.

In order to investigate VIABILITY rate of WEED SEEDs in process of dairy cow manure composting, a completely block randomized design with four replications was conducted at Veterinary Research Institute of Tehran University and WEED SEEDs Department of Iranian Research Institute of plant protection in 2010. Factors included humidity at 2 levels (with and without), adding straw (hydrocarbonic material) at 4 levels (0%, 1%, 2% and 4%) and sampling time of WEED SEEDs at 5 levels (0, 15, 30, 45 and 60 days).The experiment carried out on 13 WEED SEEDs species and percent of VIABILITY was measured. Among 13 species of WEED SEEDs, 10 species were total decay. Adding the straw, and sampling time had significantly effects on percent of VIABILITY in field bindWEED, dodder and yellow sweet clover but adding humidity had only significantly effect on percent of VIABILITY of field bindWEED. Interaction effect of adding straw and sampling time were significant at three species WEEDs, so adding 1% straw in 15th day reduced percent of VIABILITY. Adding humidity had less effect on percent of VIABILITY among these three factors.

Adding fresh manure to cropland result in an increased WEED population from SEED present in the manure. Composting process can destroy WEED SEED VIABILITY. High temperature is an important factor in decreasing of SEED VIABILITY. In an experiment the effect of season on SEED VIABILITY of sixteen important WEED species in forage fields were investigated during composting process. SEEDs enclosed within nylon mesh bags were buried into the compost pile, at 0.5, 1 and 1.5 meters depths from surface for 4 months in the early of summer, autumn and winter in 2004. The compost pile made from cow manure. SEED packets were removed monthly to test for SEED VIABILITY. The results showed that the temperature pile increased in three season and it was more than environment temperature. Temperature pile in summer was more than two other seasons. The most of WEED SEED VIABILITY loss observed in summer. Compost pile tended to have hotter temperatures at 0.5 meter than deeper layer. WEED SEEDs lost their VIABILITY at the 0.5 m depth where had the most temperature in comparison to deeper depths in all of seasons. The mean of WEED SEED VIABILITY loss after four months in summer, autumn and winter were 97.03, 83.80, 24.71 at the 0.5 m depth and 73.58, 60.71, 17.15 at all the layers, respectively.

To investigate the effect of WEED interference and WEED-free periods on Balangu (Lallemantia royleana Benth. in Wall) and to evaluate the critical period of WEED control (CPWC) in this oilSEED crop, an experiment was conducted as a randomized complete block design with three replications in Naghadeh region in 2018. Experimental consisted of two groups of treatments; WEED infestation treatments (infestation for 144.2, 345.9, 574, 848.2, 1147.6 and 1451.3 growing degree day (GDD) after transplanting and then plots were remained WEED-free the rest of the growing season) and WEED-free treatments (WEEDing for 144.2, 345.9, 574, 848.2, 1147.6 and 1451.3 GDD after transplanting and then plots were remained infested until harvesting time). In each block, one WEED free and WEED infested control was for all the growing season. Results indicated that the density and dry biomass of WEEDs were increased as WEED removal was delayed. In contrast, density and dry biomass of WEEDs were decreased as WEEDs establishment was delayed. Height, tetrachenes fruits, ripened achenes, 1000-SEED weight and biological, SEED and relative yields of Balangu were decreased and increased as the duration of WEED-infested and WEED-free period increased, respectively. Also, logistic and Gompertz curves fitted to data showed that the beginning and end of the CPWC based on a 10% yield loss of relative yield, was estimated to be from 11 to 108 days after transplanting (97 days WEED-free period) in order to prevent a noticeable yield loss.

Drying SEEDs, will increase storage time. Drying SEEDs of crops, the process is very critical because it damages embryos in the process of drying the SEEDs, their germination is lost. The results showed that damage to the embryo inside the SEED, immediately after drying operation itself does not appear. In this research factors affecting drying corn SEEDs (the Single Cross 704) to maintain VIABILITY, in a fluidized bed dryer were studied. For experiment was dried with three drying air temperature (33, 37 and 43oC), three drying air velocity (0.5, 1 and 1.5m/s) and 20% humidity at two different times (immediately after the drying process and after 6 months). After drying the SEEDs (reaching 13% moisture) and after 6 months of storage, germination tests were performed. The results showed that all of the tests, the effect of drying temperature on germination rate is significant at 1%, but the impact of air velocity dryer, even not significant at the 5% level. The highest percentage of germination is at 33oC and 0.5m/s drying air velocity.

Mechanical WEED control in field can reduce the environmental concerns due to application of herbicides and the related costs. Present study was conducted in the form of randomized complete block experimental design with six treatments and four replications in Zarghan research center of Fars Province to determine the effect of opener geometry on WEED SEEDs bank. Treatments consisted of bent leg opener, narrow point opener with rake angles of 53° and 90° , sweep opener, disc opener and moldboard plow as control. In this project, WEED SEEDs bank and WEED SEEDs location in soil was also studied. Results indicated that opener geometry affected the WEED SEEDs translocation. The bent leg opener had the highest and the lowest WEED SEEDs percentage in the soil surface and deeper layers with 26. 7% and 7. 4%, respectively. However, moldboard plow had the lowest and the highest WEED SEEDs percentage in the soil surface and deeper layers with 12. 7% and 14. 8%, respectively. These results indicates that the bent leg opener reduced vertical displacement of WEED SEEDs in soil and also reduced WEED SEEDs translocation from surface to depth of soil. Therefore, the bent leg opener can reduce WEED SEEDs bank in the long time.