جستجوی مقالات مرتبط با کلیدواژه "اوره" در نشریات گروه "گیاهپزشکی"

Bacterial canker caused by Pseudomonas syringae pv. syringae (Pss) is one of the most important diseases of peach and the use of  chemical pesticides in the control of the disease is inevitable. To determine the most effective formulation of copper bactericides, an experiment was conducted, during 2018-2020, in the form of a randomized complete block design with 20 treatments and 4 replications along the Zayanderood river. The treatments  used included copper oxychloride, copper oxide, copper carboxyl, bordeaux mixtures, fosetyl aluminium, urea and Zinc sulfate. Some treatments included a mixture of the above copper bactericides with urea or zinc sulfate, or both. The effect of the treatments on the incidence and severity of the disease was assessed by scaling the size of the canker in early June.. The first spraying was done in autumn after leaf fall and the second spraying was done before swelling of flower buds in winter. Three weeks after the second spraying, the population of Pss in peach buds was counted by isolation of the bacteria on the culture medium. The best formulations for chemical control of of peach bacterial canker were copper carboxyl or copper oxide plus urea and zinc sulfate compared witht copper bactericides alone. the highest efficacy was observed by copper carboxyl (78.7%), copper oxide (76%), copper oxychloride (48.1%) and Bordeaux mixture (45.6%), respectively, in terms of reducing disease severity. Fosetyl aluminium like copper oxychloride and Bordeaux mixtures, reduced disease severity level. Also, there was a statistically significant difference between application of urea and Zinc sulfate in comparison with the control (P = 0.05).

Termites are the common destructive pests of wood and cellulosic products in world-wide structures. In Iran, several Microcerotermes species regularly cause economic damages to wooden structures and building components in non-residential and residential areas. Microcerotermes diversus is a serious wood-destroying termite that exists in Khuzestan Province. This species has a broad scope of food foraging and also has the ability to create secondary communities within building walls and ceilings, as well as on trees. Eradication and control of this species by common methods such as the operation of drilling and injection of insecticides into the ground is faced with problems and in some cases is not always effectiveness. According to these problems, one of the effective methods of control is the use of baiting systems in which application of poisoned bait is an effectiveness control method for subterranean termites’ control. A variety of materials and toxicants have been tested to build suitable and attractive bait matrices against termites. The current research was carried out to produce a suitable formulation of toxic bait for control of subterranean termite M. diversus in Iran.
In this research, feeding responses of tested termite were evaluated to different cellulosic matrix substrates (filter papers) treated with different concentrations of molasses (ranging from 1 to 6%), urea (ranging from 0.01 to 1%), yeast (ranging from 0.01 to 1%) and soybean oil (ranging from 0.01 to 10%) additives. Non-treated filter papers were considered as control. Choice and no-choice laboratory tests were conducted. In no-choice tests, each matrix was treated with its assigned additive and allowed to be stabilized for 24hours before recording pre-trial weight. Each test matrix was separately placed in a Petri dish (9 cm in diameter) and wetted with distilled water prior to adding the termites. Then fifty termite workers were added to the Petri dishes. Experimental units were kept in a dark incubator (90±5%RH; 28±2°C) for two weeks, and termite mortality was periodically determined. The choice tests were performed following the same no-choice laboratory tests. Each experimental unit consisted of a 9cm plastic container connected to two other 9 cm plastic containers by a T-shaped tube. The central container included a mixture of soil and vermiculite (in the ratio of 2:1) moistened with distilled water, and a filter paper disc measuring 9 cm in diameter was plased in each two other plastic containers, one treated with selected concentrations of molasses, urea, yeast and soybean oil of no-choice tests and another with distilled water. Groups of foragers comprising 100 workers were placed in the central container. Experimental units were kept in a dark incubator (90±5%RH; 28±2°C) for two weeks. All experiments were conducted with four replicates. At the end of the trials, each test matrix (filter papers) was individually dried and weighed to determine feeding losses. Data analysis was done by SPSS software (version 16.0). Means were compared by Tukey̕̕ s test (no-choice test), and t-tests for two-sample paired (choice tests) (α=0.05).
The mean comparison of treatments with control through survival (after transformation the percentages to Arcsin ) showed that different concentrations of molasses and yeast did not had significant differences with compared to control. Also, there were not significant differences between soybean oil and urea and control, however 10% concentration of soybean oil and1% concentration of urea was significantly different compared with control and these two concentrations had lower survival compared with control. The mean comparison of treatments with control through feeding in no-choice test indicated that different concentrations of molasses and yeast had significant differences with control. By increasing the concentration of sugar in the molasses feeding rate is increased. Also with increasing concentration of yeast, the rate of feeding increased. The mean comparison of treatments with control through feeding showed that different concentrations of soybean oil and urea did not have significant differences with control, whereas 10% concentration of soybean oil was significantly different compared with control. With increasing concentration of soybean oil, the rate of feeding and survival of termites were greatly decreased. The mean comparison of treatments with control through feeding in choice test showed that selective concentrations of molasses (4%) and yeast (1%) had significant differences with control, but selective concentrations of urea (0.01%) and soybean oil (0.01%) did not had significant differences with control. These results confirmed the results of the no-choice test. Overall, matrices with 4% and 6% molasses concentrations and 1% yeast sustained the greatest feeding weight losses. Termite survival and matrix weight losses for different concentrations of urea and soybean oil were not significantly different with controls.
Adding of 4% molasses (w:w) and 1% yeast (w:w) to bait matrix is proposed to be used in a commercial production to increase consumption of toxic bait.

To study the effect of type and different nitrogen fertilizers on controlling Egyptian Broomrape، field and greenhouse studies based on randomized complete block with three replications، were conducted at Ferdowsi university of Mashhad. Greenhouse study treatments were consisted of ammonium nitrate، ammonium sulfate and urea each of which applied at four rates (75، 150، 300 and 350 kg/ha). Field experiment treatments were included of ammonium nitrate، ammonium sulfate and urea، applied at three rates (150، 300 and 350 kg/ha). The result of greenhouse studies indicated ammonium nitrate and urea (at all of rates) reduces Orobanch infestation about 80 percent. Ammonium nitrate and urea at (300 kg/ha) were increase tomato dry weight compare to the control. The field study findings too indicated that ammonium nitrate (300 kg/ha) was the most effective treatments in increasing tomato yield and produced highest yield (53 t/ha). Ammonium sulfate strongly decreased tomato biomass plants in greenhouse study but in field conditions produced yield same control. In conclusion we may suggest that applying ammonium nitrate fertilizer could effectively control broomrape in tomato and improve tomato growth and biomass.

The common pistachio psylla, Agonoscena pistaciae Burckhardt and Lauterer (Hem.: Aphalaridae) is one of the most important pests of pistachio trees in Iran. Cultural methods such as crop fertilization can affect susceptibility of plants to insect pests attack by altering plant tissue nutrient levels. In this investigation we studied in relation to varying fertilization levels of Ca, U, Zn and amitraz on common pistachio psylla, A. pistaciae in pistachio orchards based on complete randomized blocks with six replications and nine treatments including applied Ca, U, Zn, Uzn, Uca, ZnCa, UZnCa, amitraz and control on common pistachio psylla fed on 20-year-old pistachio trees of Ahmadaghaei rootstock in Rafsanjan orchards. The results showed that the effect of nutrient solution on nymph and eggs population had a significant difference at %1 and 5% level, respectively. The highest measure of control on eggs was related to UZnCa while the least was related to ZnCa and amitraz. The results also showed that the highest measure of pest control was related to Ca while the least was related to amitraz and UZn. The results indicated that the elements mentioned had a stronger reducing effect on the concentration of common pistachio psylla nymphs than the effect pesticide had.

Effect of different levels of nitrogen, phosphorus, iron and zinc on the activity of root-knot nematode (Meloidogyne javanica) on cucumber, cultivar Super Amelia, and the vegetative growth indices of the host plant, was investigated under greenhouse conditions. Combination of levels 0, 50, 100, 200 and 400 mg/kg of soil of nitrogen and 0, 25, 50 and 100 mg/kg of soil of phosphorous, from urea and triple superphosphate sources, respectively, also combination of 0, 2.5 and 5 mg/kg of soil of zinc and iron, from zinc sulfate and Fe-chelat sources, respectively were tested in 1.5 kg pots filled with field soil, in two independent experiments The experiments were done in randomized complete block designs, each with five replicates. Each pot was inoculated with five eggs or juvenile two/gram of soil, at six-leaf stage of plant. The results showed that application of 100 mg of nitrogen and 100 mg of phosphorus per kg of soil, also five mg of zinc and 2.5 mg iron per kg of soil caused a significant increase in the plant shoot length, shoot fresh and dry weight. The number of eggs, egg masses and galls were also decreased.