Due to its favorable weather conditions, west Azarbayejan province is the second-largest producer of sugar beet in Iran. weeds, especially field dodder, is one of the most important components that has negative effects on the quality and quantity of sugarbeet. In order to evaluate the effect of field dodder on the photosynthetic pigments and yield (quality and quantity) of sugar beet, a study using paired t-test was carried out on four farms in Urmieh-West Azarbayejan, during 2014. Studied farms had similar date of planting (first ten days of April), uniform density (8 plants per square meter) and same cultivar (Ecbatan). In this research, 30 healthy plants and 30 plants infected with field dodder were selected from each farm. Physiological and tecnicall characteristics were evaluated at the established plant stage (8-12 leaves) and at the harvest stage of sugerbeet Results showed that dodder affected efficiency of photosynthesis on sugarbeet leaves, such that it reduced chlorophylls a and b and total chlorophyll by 30, 18, and 38% respectively, but the amount of carotene was not affected. It also reduced yield by 25%, root sugar content by 108%, impure sugar by 18. 5% and foliage dry weight by 18%. Dodder also increased root nitrogen content by 37. 3%, but had no effect on potassium content.

The objective of this study was the study of tomato varieties tolerance to Orobanch aegyptica. Seeds of 26 tomato varieties: cal-g, super-b, rio-s, super-y, super-h, shef, CH, earur-vf, supst-b, CH-falat, y-falat, SDR13128, falat111, hyb1509, primoear, calgn3, erur-111, FDT202, FDT101, primo, petoerCH, kingst, viva-100, primax, petorak, primato, together broomrape seeds were sown in pots in a controlled-environment greenhouse. The characteristics of tomato cultivars were evaluated after broomrape emergence and before fruit ripenning. The following characteristics were evaluated in tomato weekly: stem dry weight, root dry weight, leaf number, stem height, and stem diameter. The following characteristics were evaluated in broomrape: stem dry weight, root dry weight, stem number. In general, it was found that the most tolerant cultivar was Petorak with 6.94 % root weight, 28.61% stem weight, and the most sensitive cultivar was Primoearly with 79.64% root weight and 99.37% stem weight reduction. It is notable that broomrape showed minimum shoot number and shoot dry weight as grown together Petorak cultivar.

In order to study to evaluate the tolerance of some tomato (Lycopersicon esculentum L. ) cultivars and landraces to Egyptian broomrape (Orobanche aegyptiaca pers. ) an experiment was conducted as completely randomized design with 3 replications in greenhouse conditions. In this experiment, 23 cultivars and 4 landraces of tomato were planted in two series of treatments (infected and uninfected (control) with broomrape). Results showed that tomato cultivars and landraces had a significant difference in their biomass and broomrape reduced fresh and dry weight of all all tomato cultivars and landraces significantly. Urbana, GS15, Marconi cultivars and all landraces of tomato were the most susceptible hosts to broomrape. In contrast Cal-jN3, Primo, Hyb. Petopride V, Hyb. Xaman and Hyb. Super Set showed lowest loss percent of shoot and root dry weight in present of broomrape compared to other cultivars. Also, comparison of tomato landraces and cultivars showed that despite higher biomass production of the landraces in control treatments, they were more susceptible and suffered more severe damage in infected treatments.

To evaluate the effect of nitrogen and water withholding in vegetative growth stage of corn on efficacy of nicosulfuron and 2,4-D+ MCPA an experiment was conducted as a factorial arrangement in a randomized complete block design with three replications at Tarbiat Modares University in 2017. The first factor contained four treatments including application of nicosulfuron, 2,4-D+ MCPA, weed free and weed infested as control. The second factor consisted of normal irrigation and water withholding from 4 to 8 leaf stage. Third factor contained either urea application or no fertilizer application. Normal irrigation and nitrogen fertilizer application significantly increased nicosulfuron and 2,4-D+ MCPA efficacy in weed control and total weed dry weight decreased to 341 and 361 g.m-2 respectively compared 1370 g.m-2 as weed infested. Nicosulfuron and 2,4-D+ MCPA reduced weed total dry weight significantly under irrigation withholding. Grain yield increased with application of nitrogen and nicosulfuron. Grain yield was higher with application of 2,4-D+ MCPA than nicosulfuron without nitrogen application under irrigation withholding. Application of nicosulfuron with nitrogen application provided satisfactory weed control and increased grain yield.

Introduction of sugar beet cultivars with tolerance to dodder is considered an inevitable necessity in the management of this Parasitic weed, and conducting comprehensive research in this area is of great importance. Therefore, the tolerance of eight sugar beet cultivars including Ekbatan, SBSI061, Arta, Aria, Sina, Shokoofa, Paya, and Sharif, was evaluated against dodder in pot and field trials. The pot trial was carried out in the spring of 2021 in the greenhouse of the weed research department and in the spring of 2022 in the research field of Iranian Research Institute of Plant Protection in Meshkindasht, Alborz. Among studied traits, fresh weight of sugar beet root, dodder fresh weight, and the ratio of dodder fresh weight to shoot fresh weight of sugar beet played an important role in determining the tolerance or susceptibility of sugar beet cultivars to dodder. Results showed that Ekbatan and Shokoofa experienced the lowest and highest reduction of the above-mentioned traits, respectively under contamination with dodder; because the root fresh weight reduction was the lowest (41.5 and 14% in greenhouse and field, respectively) in Ekbatan and the highest (63.5 and 96% in greenhouse and field, respectively) in Shokoofa. On the other hand, in the presence of Ekbatan and Shokoofa cultivars, dodder had the lowest (41 g pot-1 and 16g m-2 in the field) and the highest (82.5g pot-1 in the pot and 52.3 g m-2 in the field). In addition, the ratio of fresh weight of dodder to shoot of sugar beet was the lowest (0.97 and 0.11 in greenhouse and field, respectively) in Ekbatan and the highest (2.53 and 0.46 in greenhouse and field, respectively) in Shokoofa, respectively. Therefore, among studied cultivars, Ekbatan and Shokoofa are introduced as cultivars with greater tolerance and susceptibility to dodder, respectively.

Experiments, in Petri dish and greenhouse, were carried out to investigate the efficiency of three herbicides (rimsulfuron, imazapic and imazamox) in controling broomrape. In Petri dish study, herbicides were applied at 0.05, 0.25, 1.25, 6.25 and 31.25 micro-mole doses to broomrape seeds at germination stage without a host plant and adding GR24 as stimulator. In the greenhouse experiments, the efficiency of these herbicides to control broomrape in two varieties of tomato (Viva and Hyb.Petopride II) was investigated. Treatments were four doses of rimsulfuron (25, 50, 75 and 100 g ai/ha), imazapic (5, 10, 15 and 20 g ai/ha) and imazamox (0.4, 0.8, 1.2 and 1.6 g ai/ha) at one, two and three applications. Results of Petri-dish experiments showed that rimsulfuron and imazapic significantly reduced radicle elongation of seedlings as compared to the control, while, imazamox did not have any effect on broomrape seed. Each dose was applied for one, two and three times with in 15, 29 and 43 days after within transplanting tomato seedlings. Results of pot experiments indicated that the responses of two tomato varieties herbicides were different. Viva was responsive to herbicidal effect and produced higher biomass than Hyb.Petopride II. Rimsulfuron was a suitable herbicide in tomato to control broomrape. Rimsulfuron at doses of 25, 50 and 75 g ai/ha (three times of application) were the best doses, specially in viva were the best treatments for broomrape control and producing tomato biomass. Imazapic also, at 5 g ai/ha (two times of application) and 10 g ai/ha (single application) was an effective treatments in variety of viva. Imazamox treatments did not appear to be suitable herbicides in this study.

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.

Orobanche species, commonly known as broomrape, are root holo-parasite of the family Orobanchaceae.  In Nepal two species, Orobanche aegyptiaca and O. cernua are causing threat to wide range of important vegetables and crops of family Brassicaceae and Solanaceae. To evaluate non-host plants as potential trap crops, different crop plants were tested in two Orobanche infested tomato fields of Lalbandi, Sarlahi, South-Eastern part of Nepal in 2018 -19. Orobanche seed density in soil samples collected from plots before planting and after harvest of each crop species were recorded and compared for the seed bank. On the basis of Orobanche seed bank reduction in both the fields, the investigated crop species like Capsicum frutescens, Cicer arietinum, Lens culinaris and Vicia faba were classified as highly potential trap crops and reduced seed bank from 52 to 70%. Crops like Cuminum cyminum, Daucus carota, Foeniculum vulgare, Phaseolus vulgaris, Sessamum orientale and Trigonella foenum-graecum were classified as moderately potential trap crops and reduced Orobanche seed bank from 41 to 52 %. The other tested crops like Allium cepa, Allium sativum, Coriandrum sativum, Glycine max, Hordeum vulgare, Pisum sativum, Solanum tuberosum, Raphanus sativus are classified as non- potential trap crops. Among all the tested crops Capsicum frutescens, Cicer arietinum, Lens culinaris and Vicia faba were identified as the potential trap crop to reduce Orobanche seed bank in infested tomato fields.

Introduction: Dodder (Cascuta campestris Yuncker) is an annual Parasitic plant from the Convolvulaceae family (Mishra et al., 2007). It wraps around many adjacent dicot and a few monocot plants, penetrates in their vascular tissue and exploits photosynthates, nutrients and water (Lanini & Kogan, 2005). Consequently, the growth, vigor and production of the host plant will be severely reduced (Nadler-Hasasr & Rubin, 2003). Dodder is not able to complete its cycle, if it is not attached to a host. Therefore, it is entirely dependent on its host for supplying water, assimilates and minerals (Mishra et al., 2007).Considering the nature of dodder habit, it is rarely possible to completely control dodder by using different chemical herbicides (Lanini & Kogan, 2005). In addition, because of increasing the environmental concerns caused by applying synthetic herbicides, there is considerable attention to alternative strategies for weeds management (Batish et al., 2002; Bowmik & Inderjit, 2003).In recent years, allelopathic plants, an alternative strategy for weed management, have received massive attention (Narwal, 2010; Jamil et al., 2009). Due to the importance of dodder as a Parasitic weed, this research was conducted with the purpose of studying the allelopathic effects of aqueous extracts and decay durations of caster bean (Ricinus communis L.) organs on germination and emergence of dodder.Materials and methods: The current study was conducted based on three separate experiments using a completely randomized design (CRD) with factorial arrangement with three replications. The first experiment was conducted in petri dishes and consisted of caster bean organs at four levels (root, stem, leaf and total plant without inflorescence) and their aqueous extract concentrations at 11 levels (0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10%). The second experiment was conducted in pots and factors were caster bean organs at 4 levels (root, stem, leaf and total plant without inflorescence) and their aqueous extract concentrations in 5 levels (0, 2.5, 5, 7.5 and 10%). The third experiment was conducted with caster bean organs at 4 levels (root, stem, leaf and total plant without inflorescence) and decay durations at 8 levels (0, 15, 30, 45, 60, 75 and 90 days of decay and control).All experimental data were analyzed by ANOVA and the means were separated by Duncan's multiple range test at 5% probability level.Results and discussion: The results of the first and the second experiment showed that aqueous extract of caster bean organs has a significant effect on dry weight, length of seedling and germination of dodder. From the third experiment, decay duration had a significant effect on the mentioned traits. Leaf aqueous extract in comparison with other organs had the most effect on the studied traits. The complete suppression of emergence was observed in 0, 15, 30 and 45 days of decay by using caster bean leaves.In conclusion, caster bean residues showed great potential for reducing germination and growth of dodder.Therefore, allelopatic potential of caster bean can be considered as a sustainable approach in integrated dodder management systems. In the future, the effective concentrations of aqueous extracts of caster bean organs may be useful as sources for producing biological herbicides.

Some parasites are innocuous or even beneficial to mammalian hosts. The gastrointestinal helminths modulate several important intestinal functions such as immunomodulation. . . .