نشریه آفات و بیماریهای گیاهی
سال هشتاد و نهم شماره 1 (پیاپی 112، شهریور 1400)

Cowpea is widely cultivated worldwide and used as an important food source. Tartanychus urticae, Koch is one of the Cowpea is widely cultivated worldwide and used as an important food source. Tartanychus urticae is one of the most important pests of beans. This study was conducted to optimize the use of acaricides by Central Composite Design, CCD, and Response Surface Method, RSM, using Design Expert 7.00 software to reduce the use of chemical pesticides and to evaluate the optimal conditions for whole female mortality. Process input variables were in the temperature range of 25–30°C, 55–65% humidity and 200–1260, 900–2300, 69–2330  ml /1000 ml  H2O for Fenphyroximite, Propargitis and Fenazaquin, respectively. Eye– popping bean leaf discs were used for inoculation and bioassays. The results of analysis of variance confirm that the linear model and the dose and relative humidity factors are statistically significant with the best peak mortality of mite for Fenphyroximite, in H: 57.03% and D:1045.14 ml /1000 ml  H2O, M:22% and the significance of the 2FI quadratic model, temperature and relative humidity interactions for propargite mites with the lowest dosage,T:26.01 °C , H:62.97% about M:16% and linear model with humidity factor for use of Fenazaquin with best mortality rate of full female mites at H: 62.97%, D: 527.30 ml /1000 ml  H2O, about M: 9% which the most favorable conditions for use the three acaricides. s

Common bacterial blight disease (CBB) of bean (Phaseolus vulgaris) caused by Xanthomonas phaseoli (Xp) is considered as one of the most deleterious pathogens for bean production in the world. In this study, 105 samples were collected from asymptomatic wild fabaceous plants, i.e. Astragalus ovinus, Vicia villosa and Vicia lutea, grown in Zagros forests of Iran. The plant samples were cultured on nutrient agar and purified. The isolates were then screened for some important criteria for biological control such as phosphate solubilization, protease activity, IAA and H2S production, and antagonistic effect. Three endophytic bacterial isolates were found as potential biocontrol agents against Xp. Based on key biochemical tests and comparative analysis of the partial 16S rDNA sequences, the isolates were identified as Pseudomonas fluorescens and two Bacillus species. Under greenhouse conditions, all the three strains significantly increased shoot and root lengths in bean plants at the 5% level (P < 0.05) and decreased disease severity above 70%. This is the first report on the presence and capabilities of endophytic bacteria from wild leguminous plants in the Zagros Mountain steppe forests of Iran.

Date Palm Lessr Moth Batrachedra amydraula Meyrick, is among the most important pests feeding on date fruits. Here, we studied the standardization of the class-specific sampling method to define the appropriate unit and number as well as to know population distribution pattern of B. amydraula in its specific ecological niches and fitting of continuous sampling model on six date palm cultivars in five provinces. Sampling was repeated in 10 days intervals from late March to early September. Distribution pattern of B. amydraula in the date palm orchards was calculated using indices of mean crowding, Taylor's law, mass average index, patchiness, and Iowa. The results showed that the mean density of B. amydraula varied from 3.304 (Sayer cultivar) to 0.804 (Rabi cultivar) in 20 studied fruits. According to Taylor's law, the distribution of this pest was cumulative. The sample size decreased by increasing density of B. amydraula in date palm orchards. The slope of decrement was different in the various date cultivars so that the lowest and highest number of the samples were observed in Sayer and Kabekab, respectively. By these results we can say that sequential sampling method can decrease sample size by 3 to 16 times compared with the classical sampling model.

The Mediterranean fruit fly (Medfly), Ceratitis capitata (Wiedemann, 1824) is one of the most destructive pests of citrus fruits in Mazandaran province of Iran. The mass trapping approach based on using female and male-targeted attractants was carried out in a citrus grove, mainly early ripening clementine variety with a few number of fig, persimmon and pomegranate trees (1 ha) using Tephri-trap (with Cera-lure as a food attractant for females) and Jackson trap (with Trimedlure as a sexual attractant for males) and control plot (0.5 ha) in two successive years. In total 93 traps were installed and distributed on one-third of citrus trees in treated plots. All traps were placed 1.5-2 m above the ground, slightly inside of trees canopy. For each Jackson trap, three Tephri -traps were set. Monitoring of adult populations of Medfly in the treated and control plot was performed using two Delta traps per plot. Tephri-traps were serviced once every two weeks and Trimedlure dispensers of Jackson traps were replaced every two months. The achievement of mass trapping was on randomly examining of 100 fruits every week from September until harvesting time (i.e. November). At the end of experiment, approximately 35010 female and 4333 male flies were trapped in the treated orchard. Data analysis indicated significant differences (P<0.0001, df=11, t=32.22) between fruit infestation percentage to the Medfly in treated and control plots. The pest control was fully satisfactory and fruit damage by Medfly was less than 0.5%, compared to the control plot (40%).

Cultural control is one of the oldest methods for insect pests’ management. To elucidate the role of cultural activities on population fluctuations of Dubas bug (Ommatissus lybicus De Bergevin), 12, 19, and 29 date palm plantations were chosen as sampling plots in Abadan, Behbahan and Bam, respectively. Samplings were done using the cluster random method. Population densities were estimated by leaf sampling and yellow card installations. The impact of management activities was evaluated by direct observations and interviews with plantation owners and extension service officers. Results showed that the efficiency of management factors in population reduction was of different values so that the pattern of cultivation including intercropping and planting space, nutrition management, and other activities including leaf pruning, basal offshoot removal, and chemical control were effective in population reduction.

Impurities of a pesticide, even in very small concentrations, is toxic and in some cases may be equivalent or greater than the active ingredient of the pesticide. This toxicity can be dangerous for the consumer of agricultural products as well as the environment. So, in this study, the purity percentage of chlorpyrifos as well as the amount of its two important impurities sulfotep and 3, 5, 6-trichloropyridinol (TCP) were evaluated in their technicals. The technical samples of 31 formulation companies in Iran were randomly sampled and analyzed by LC-MS/MS instrument equipped with a triple quadrupole analyzer. The results showed that 6.4% of the technical samples contained the active ingredient less than the standard limit. In 9.7% of the samples the amount of sulfotep was higher than the value recommended by FAO. The amount of TCP was higher than the standard level in 32.2% of the samples. The results of this study showed that reliable sources of the pesticide technical supplies and the evaluation of their impurities are inevitable necessities and should be given serious attention in their quality control stages.

Olive fruit fly Bactrocera oleae (Rossi). (Dip.: Tephritidae) is the main pest of olive orchards in Guilan, Qazvin and Zanjan provinces. In this study seasonal population fluctuations, bio-ecology characteristics and olive orchard infestation were investigated in the orchards of Tarom Sofla (Ghazvin province) in 2014- 16. Sex pheromones (on yellow sticky traps) were used to catch the adult flies and fruit sampling carried out to reveal the pest development and fruits infestation rate. Based on the results, flight activity of the adults occurred throughout the season with different densities, which depends on weather conditions. The fly had 3-4 overlapping generation per year. Immature stages observed in mid-Jun. Ovipositing in the fruits (1st generation) started in late spring and early summer, coinciding with pit hardening. The 2nd generation found from mid-August to mid-September and the 3rd generation started from end of September. In three years, the fruit infestation means at Kalaj and Ghoshchi were 2.4%, 5.1%; 4.7%, 6.2% and 8.7%, 21.3%, respectively.

The abundance of the western flower thrips, Frankliniella occidentalis, along with the onion thrips, Thrips tabaci, in the greenhouse of tomato, cucumber, Alstroemeria, Rose and Gerbera were determined by weekly sampling from November 2018 to May 2019 in Isfahan districts. The competition ability of these two species on cucumber was evaluated by comparing their fertility-life table parameters at two different temperatures and also by measuring the density of each species over time with different initial densities of both species. The results showed that the population of the western flower thrips was always higher than onion thrips in greenhouses. The fertility- life table parameters showed that an increase in temperature leads to increase the western flower thrips’s population. At 25 ° C, the intrinsic rate of increase (0.17 day-1) and the net reproductive rate (51 nymphs) of onion thrips were higher than the western flower thrips, and at 27 ° C the western flower thrips had higher intrinsic rate of increase (0.18 day-1) and net reproductive rate (45 nymphs) than those of onion thrips. Since the value of intra-specific competition for onion thrips (0.34) and western flower thrips were 0.34 and 0.14, respectively. The onion thrips population growth is more affected by intraspecies competition than western flower thrips and so the western flower thrips is more successful in interspecific competition than onion thrips.

The physiological feeding reactions of cotton bollworm were investigated by evaluation of nutritional indices and enzyme activity of larvae reared on different rapeseed cultivars including, Sarigol, Rgs003 and Slm046. The experimental plants were treated by amounts of urea fertilizer equivalent to 120, 240 and 360 kg per hectare, in three development stages of plants. The nutritional indices of Helicoverpa armigera on different rapeseed cultivars were calculated by Waldbauer's formula. The total leaf protein in three rapeseed cultivars were significantly increased with increase of nitrogen level. The lowest and highest values of measured nutritional indices were observed in larvae reared on control and treated plants with 360 kg/hec of nitrogen, respectively. Also results indicated that there was not significant difference between larval nutritional indices which reared on plants treated with 120 and 240 (kg/hec). Similar results were obtained for larval digestive enzyme activity.

Resistance development to both insecticides and transgenic crops has been frequently reported in Helicoverpa armigera populations, necessitating efforts to find new control measures. This study was aimed to evaluate the efficiency of attract and kill method using Noctovi®, a synthetic plant volatiles-based attractant for controlling H. armigera. In addition, the attractiveness of the Noctovi® for adults of H. armigera was evaluated under field conditions using delta traps. One liter per hectare of Noctovi® mixed with Permethrin, 5 ml A.I. or Thiodicarb, 7 ml A.I. was sprayed on tomato plants of the middle row (100 m length) just before sun set every two weeks. As infestation criteria, means percentages of infested tomatoes in attract & kill, insecticidal treatment and control (without any treatment application) plots were statistically compared. The results revealed that the Noctovi® was attractive for gravid females and males of H. armigera. Means percentages of infested tomatoes in attract & kill, insecticidal treatment and control (respectively 2.91±0.18, 4.68±0.24 and 5.14±0.28) were significantly different and the infestation in attract & kill treatment was significantly less than those of insecticidal treatment and control ones. At the same time, the infestation in insecticidal treatment was significantly less than that in control.

Cabbage aphid, Brevicoryne brassicae (L.), is one of the most important pests of the canola in different parts of Iran. This pest causes significant damage on leaves, stems, flowers and pods of canola. In this project, the effect of seven canola cultivars (Okapi, Licord, Talayeh, Modena, Tasilo, Hyola308 and Hyola401) was studied on developmental time and reproductive parameters of B.brassicae under greenhouse conditions (20 ±2 °C, 50 ± 5% RH and 16 light: 8 darkness). Base on the results, Hyola401 and Hyola308 hybrids showed the highest value of intrinsic rate of increase ( ) and shortest duration of immature stage, so they were the most suitable hosts for the pest, whereas Okapi, Talayeh and Tasilo cultivars showed the lowest value of  and the longer duration of immature stage and were unsuitable hosts for development and reproduction of the pest under greenhouse conditions, therefore they are recommended for use in integrated management of the cabbage aphid.

Water hardness and acidity are the important properties that can influence the performance of pesticides. The effect of water hardness and pH on the efficacy of insecticides on second instar nymph of Bemisia tabaci was determined by leaf dip method. In the first experiment, well water samples at 1869, 645, and 265 mg L-1 hardness, standard, and deionized water with malathion, acetamiprid, and spiromesifen used for bioassay. In another experiment, the effect of water pH at four levels 4, 6, 7, 9 on the toxicity of the above three insecticides was investigated. Increasing water hardness reduced the performance of the experimental insecticides. LC50 values showed that the toxicity of malathion, acetamiprid, and spiromesifen was 40, 157, and 84 times less in water with 1869 mg L-1 hardness than deionized water. The efficiency of malathion, acetamiprid, and spiromesifen was 13, 65, and 39 times less in water with 645 ppm hardness than deionized water. Pesticides were less effective at pH 9 compared to other pH levels. Malathion efficacy was 11.41 and 7.16 times better when it was diluted in water with pH 6 and 7 than pH 9. Acetamiprid provided 10.72 and 5.89 times greater toxicity when applied at pH 7 and 6 respectively than water with pH 9. Spiromesifen in deionized water with pH 7 and 6 has exhibited 5.51 and 3.82 times better efficacy compared to the water at the pH level of 9. Overall, the performance of insecticides reduced at hardness levels above 265 ppm and in alkaline pH.

The cereal cyst nematode Heterodera filipjevi has obligatory diapause stage in life cycle. For this purpose, the effect of different thermal treatments viz. 5, 10, 15, 5+15, 20 and 25°C were tested on the number of egg hatching of H. filipjevi for 12 weeks. The highest hatching rate was observed at 5+15°C with 87.8% whilst the treatment 25°C showed the lowest hatching rate of 1.1%. The treatments 5°C and 5+15 °C with highest hatching rates respectively showed significantly increasing of hatching between the sixth and seventh weeks followed by decreasing from the eighth week. Therefore, a pre-hatching incubation temperature at 5°C for six weeks is required to breaking diapause in Iranian population of H. filipjevi to occur the highest hatching rate at 15°C and by increasing the temperature the hatching rate is decreased.

Phytonemus pallidus (Banks) reported for first time from New York in 1898. At present, cyclamen mite has a worldwide distribution on cultivated strawberry plant in different states of USA, South American countries, Japan, Taiwan, Korean republic, South Africa and European countries like The Netherland and Turkey (Denmark, 2016). Host ranges of cyclamen mite has been reported on African violet, begonia, gerbera, ivy, chrysanthemums, geranium, fuchsia, larkspur, petunia, snapdragon (Denmark, 2016).This mite is exotic pest to strawberry plants in Iran. For the first time this mite found on Parvous, Queen Eliza, Kurdistan, Aromas, Camarosa, and Selva strawberry varieties in Kurdistan province of Iran (Kamangar et al., 2016). After that, the mite also collected on different weed species such as Senecio sp., Lamium amplexicaule, Polygonum lapathifolium, Amaranthus sp., Plantago sp. Sencio vulgaris, Veronica persica and Malva sylvestris in Kurdistan province (Mansour Ghazi, 2018). The first invasive cyclamen mite damages on greenhouse strawberry observed on sabrina and camarosa varieties in range of 16-22 degree Celsius and above70% relative humidity during autumn season in several greenhouses of strawberry in Hashtgerd vicinity of Alborz province. Developmental stages of this mite consist of egg, larvae, pharate female, adult male and female. Male and female of cyclamen mite easily distinguished through fourth pair of legs which tarsus of male terminated  with strong claw, used for holding and carry pharate female stage for mating  while tibia and tarsus segments of fourth pair of legs in female, combined  together ending with two long and short setae. Color of larvae and pharate female are whitish whereas female and male changed into yellowish color. The main damages of cyclamen mite caused by injecting toxin to newly emerged leaves, petioles of leaf, sepal of flower, changing color of infested plant parts into brown, reduce growth, protect fruit formation and death of infested plants finally. Sometimes, these symptom of injuries initially may confused with phytoplasma diseases on strawberry plants. Results of biological control studies of cyclamen mite by two phytoseiid predatory mites (Neoseiulus californicus (McGroger), N. cucumeris (Oudemans) revealed that, 76% control achieved on active P. pallidus stages only (Easterbrook et al., 2001). Most of sign of cyclamen mite injuries observed around heating system and hot air blowing direction on Camarosa and Sabrina strawberry varieties in the greenhouses in Hashtgerd vicinity of Alborz province. Free strawberry seedling from cyclamen mite infestation protect cultivated plants from further severity mite damages during growing and harvesting periods.

Fruit russeting is one of the important symptoms affecting marketing of apple (Malus × domestica Borkh.) fruits. The study had been conducted in Semirom region, Iran, in 2019 showed that one of casuals of fruit russeting is stem-end russeting caused by yeast-like fungi Aureobasidium sp. (Heidarian et al., 2020). Easterbrook and Fuller (1986) reported apple rust mite, Aculus schelchtendali Nalepa (Acari: Eriophyidae) as a causative of russeting on apple fruits. In some orchards of Semirom region, in addition to two common cultivars (Red Delicious and Golden Delicious), several other cultivars (including Golab-e-Isfahan, Golab-e-Kohanz, Miracle, Granny Smith and Fuji) were also cultivated. Miracle is one of the apple cultivars was recently introduced to the country and its cultivation area has been increased. This cultivar has export value and a high marketability due to its desirable color. During the study on the causative agents of fruit russeting in 2017 and 2018, some rusted fruits of Miracle cultivar were found, with similar symptoms to apple rust mite. Infested leaf and fruit samples were collected, and their microscopic slides were prepared in the laboratory after clearing the mites. To check possible infestation of different apple cultivars to the mite, their leaf and fruit samples were collected and compared with the typical symptoms of its damage. Specimens of the mite were identified by the third author as Aculus schlechtendali Nalepa (Acari: Eriophyidae). In Iran, apple rust mite was reported firstly by Sadeghi Nameghi (1995) from Mashhad on apple leaves. However, this is the first report of the mite as the causing agent of fruit russeting in Iran. Examination of the infested fruits showed that the damage appears as russeting around the calyx which gradually covers the entire surface of the fruit to varying degrees. Moreover, feeding of the mite on underside of the leaves causes browning of the leaves in summer (Figure 1). Generally, damage intensity and fruit russeting from apple rust mite is related to population density of the mite, cultivar and plant age (Easterbrook and Fuller, 1986). In the present study, damage of apple rust mite was found only on Miracle cultivar. Regarding increasing of cultivation area of this cultivar in some apple orchards around the country, it is necessary to be careful for possible increase of population density of apple rust mite, because the mite, in addition to direct damage, could reduce marketability of the cultivar, due to the occurrence of fruit russeting.

Strawberry, Fragaria ananassa Duch. which belongs to the Rosaceae family is one of the most important micro-fruits of temperate regions that has been considered as one of the most important and commercial products in the recent decades. Golestan province is the third largest strawberry producer in Iran after Kurdistan and Mazandaran Provinces (Ahmadi et al., 2018). Spodoptera littoralis (Boisduval, 1833) is a highly polyphagous pest that attacks to a wide range of crops (Lanzoni et al., 2012). The eggs are whitish-yellow in color, spherical, somewhat flattened, with 0.6 mm diameter, surrounded by hair scales. The newly hatched larvae are 2 to 3 mm long with white bodies and black heads and are very difficult to detect visually. The larvae are hairless, cylindrical, and variable in color from blackish-gray to dark green, becoming reddish-brown or whitish-yellow. They have dark and light longitudinal bands on lateral sides; and with two dark semilunar spots on each segment (except for the prothorax) dorso-laterally. This pest has 5-6 larval instars, and length of full grown larvae is 40-45 mm. The pupae are cylindrical, 14-20 5 mm, and the last segment ends in two strong straight hooks. Firstly in green with reddish color on the abdomen, turning dark reddish-brown within few hours. The adult moth with length of 15-20 mm, and wingspan of 30-38 mm. It has a gray-brown body, with gray to reddish brown forewing that has paler lines along the veins, and grayish white hind wing, iridescent with gray margins (Pinhey, 1975).Based on the available literature, the larvae ofS. littoralis are newly observed in Golestan Province on strawberry (Fig. 1). In the early stages of damage, the young larvae feed on small areas on the underside of the leaf. Older larvae make large holes in the leaves or eat them completely, or damage young branches, young buds and bare parts of the stems, severely. In the Khan Bebin fields where strawberry bushes left in the ground to produce stolons for reproduction, the larvae started to feed on the leaves from the early September, and with increasing the larval age, their feeding intensified and eventually caused destroying the central meristem of the plant. Egyptian cotton leaf worm with its high ability of reproduction, and feeding, can be considered as a serious and very important pest in Golestan province, due to the climatic conditions of the region.

Several chamomile plants (Matricaria chamomilla L.) showing reduced growth were observed and collected from some fields of medicinal plants in Harsin (Kermanshah province), during summer 2020. The land had been under cultivation of sugar beet crop with Beet necrotic yellow vein virus-BNYVV infection. Samples were tested using ELISA (Clark. and Adams, 1977) and RT-PCR assays for probable BNYVV infection. Seven out of nine tested samples showed positive reaction in ELISA. Three of ELISA positive samples were selected and tested for BNYVV infection by RT-PCR using specific primers designed in this study to amplify part of the coat protein (CP) gene of BNYVV. A DNA fragment with the expected size of 570 bp was amplified in all three tested samples. The nucleotide sequence of the amplified DNA fragment of one of the tested samples (Cham7) was determined (MZ368701) and compared with the available sequences in GenBank using the BLAST tool at the NCBI database. Based on the results, our obtained sequence showed the highest identity (>99.6%) with previously reported CP gene sequences of BNYVV. A soil sample was collected from the same original farms in which chamomile plants had been collected for tests. Seeds of chamomile plant were disinfected and cultivated in soil sample and RT-PCR assays confirmed BNYVV infection. Widespread infection of BNYVV in sugar beet fields has been previously reported from Iran (Farzadfar, 2009). BNYVV has been previously reported from German chamomile (Chamomilla recutita) in Turkey (Kutluk et al, 2000), however, this is the first report of natural infection of BNYVV on chamomile plant in Iran.