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Aim The present research was conducted to investigate the effect of Plant Growth Promoting Rhizobacteria (PGPR) and deficit irrigation on quality and quantity of flax under field and pot conditions to determine bacterial efficiency and to decrease water deficit effects. Methods and results Initially, in vitro experiments were performed to determine the growth-promoting characteristics of bacteria. Then in the field, the effects of bacterial inoculation (control, Azotobacter chroococcum, Azospirillum lipoferum, Bacillus amyloliquefaciens, Bacillus sp. strain1, and Pseudomonas putida) on flax traits were evaluated at different irrigation levels (100%, 75%, and 50% crop water requirement). Bacterial treatments in the pot experiment were selected based on the field experiment results. The irrigation regimes in the pot and field experiments were the same and bacterial treatments included single, doublet, and triplet applications of the bacteria. All the bacterial strains could solubilize phosphate, produce ammonia (except for Bacillus sp. strain1), indole acetic acid, and siderophore (except P. putida). Field results indicated that the bacteria significantly mitigated the effects of water deficit. Compared with control plants, bacterial treatments increased the oil, linolenic acid, protein, and sulfur content; the number of shoots and capsules; and the harvest index in the flax plants. Pot experimental results revealed that the combined inoculations were more effective than single inoculum treatments. Conclusions Bacterial inoculation alleviates deficit irrigation effects in flax plants. Significance and impact of the study The effectiveness of applying A. chroococcum, B. amyloliquefaciens and Bacillus sp. strain1 was confirmed, especially as a combination to protect flax against water deficit and to improve its nutritional quality and growth.

Stored-product pests in the family Bruchidae of Coleoptera represent important pests affecting legume seeds. The lentil weevil, Bruchus lentis Froelich (Coleoptera: Chrysomelidae: Bruchinae) is one of the major lentil pests in Iran and in the world. The economic losses caused by this pest on lentil grow up to 40%. Synthetic pesticides are currently the chosen method to protect stored grain from insect damage. However, their widespread use has led to the development of pest strains resistant to insecticides and pest resurgence. In recent years, nonchemical methods, including biological agents are considered safe methods to control the stored grain pests. Positive characteristics of entomopathogenic nematodes as biological control factors of arthropod pests, introduce them as an appropriate option for controlling the integrated pest management of lentil weevil. In the present study, an isolate of entomopathogenic nematode, Steinernema feltiae, isolated from soils around Yasouj and based on morphological traits and morphometric data were identified. Adult insects of lentil weevil were exposed to concentrations of 0; 500; 1,000; 2,000 and 3,000 infective juvenile/ml of distilled water at different temperatures (20, 23, 26 and 29 °C). Insects were placed on filter paper impregnated with 1 ml of nematode suspension in Petri dishes for three days. Mortality of the insects was recorded every 24 hours. The highest mortality was recorded after 72 hours, which represented 79.40%, at the concentration of 3,000 infective juvenile at 26 °C.

Tuta absolute was a quarantine pest in Iran that has been recorded for the first time in 2009. The most conventional methods for control of this pest in Iran are chemical methods and mass trapping, although the efficiency of the latter method is not clear. In 2013, the efficiency of three common types of solar light traps with and without sex pheromone, along with water pan pheromone traps for control, were investigated. The experiment was performed in a randomized complete block design within in a tomato field. The treatments were Behroyan light trap (BL), Zist bani light trap (ZL), Russell light trap (RL), BL + pheromone, ZL+ pheromone, RL+ pheromone and water pan pheromone trap (WPT). Traps were checked weekly and the number of captured tomato leaf miner (TLM), Noctuid moths, Chrysopa sp., Coccinella septempuctata and Syrphid flies were counted. Mean weekly capture of TLM in BL, ZL and RL traps without sex pheromone were 9.11 ± 1.16, 4.94 ± 0.24 and 1.66 ± 0.7, while within traps sex pheromone were 54.72 ± 11.8, 42.05 ± 6.47, 39.02 ± 2.82, respectively. The mean weekly capture of Noctuid moths in the traps without pheromone were 16.92 ± 1.39, 25.39 ± 0.57, 1.49 ± 0.27 and with pheromone were 21.04 ± 1.72, 28.09 ± 0.95, 2.76 ± 1.39, respectively. Mean weekly capture of TLM and Noctuid moths in WPT traps were 47.13 ± 3.06 and 0.73 ± 0.27, respectively. The total attracted numbers of predators by the three light traps were not significant. In conclusion, traps baited sex pheromone (especially BL and ZL) could be used as eco- friendly tools for mass trapping of TLM and some key Noctuid moth pests in isolated tomato fields.

The Safflower capsule fly (SCF), Acanthiophilus helianthi Rossi (Diptera: Tephritidae) is the most destructive insect pest attacking the Safflower Carthamus tinctorius L. plant which are cultivated as an oil crop. It is mainly controlled through application of broad-spectrum insecticides, which can adversely affect safflower farms ecosystem and consequently human health. Since a first step in setting up an integrated pest management program is to assess the biological control agents within the ecosystem. Therefore, in this research work the pupal parasitoids of Safflower capsule fly a main insect pest attacking Safflower plants were identified. The impact of these parasitoids against this pest was evaluated on the varying pest generations and within different locations in Kohgiluyeh province during 2008-2009 seasons. Pupal parasitoid adults of SCF were recorded from fieldreared pupae, which had been collected from heavily infested small flower heads of the first generation as well from large flower heads of the second and third generations. Rate of parasitism on A. helianthi pupae was estimated as the number of parasitoids over the total count of parasitoids and flies. Ten hymenopterous species belonging to different families parasitizing insect pupae were screened as follows: Bracon hebetor (Spinola, 1808) and Bracon luteator (Spinola, 1808) (Braconidae); Isocolus tinctorious (Melika and Gharaei, 2006) (Cynipidae); Pronotalia carlinarum (Szelenyi and Erdos, 1951) (Eulophidae); Eurytoma acroptilae (Zerova, 1986) (Eurytomidae); Ormyrus orientalis (Walker, 1871) (Ormyridae); Colotrechnus viridis (Masi, 1921) and Pteromalus sp. (Walker, 1976) (Pteromalidae); and Antistrophoplex conthurnatus (Zerova, 2000) and Microdontomenus annulatus (Masi, 1899) (Torymidae). The average parasitization rate was 23±1 as revealed through the present study. The highest parasitization rate occurred during the first generation in all localities tested, as well as in years. Statistical analysis revealed that there were significant differences between parasitization rates by pupal parasitoids within various host generations and localities.

The insecticidal properties of essential oils prepared using water distillation method from aerial parts of Mentha piperita, Mentha pulegium, Zataria multiflora and Thymus daenensis were investigated on adult of Bruchus lentis and Callosobruchus maculatus. Essential oils were used in five concentrations and five replications. Mortality rate of insects were recorded after 3, 6, 24, 48 and 72 hours. Results indicated that the longer exposure of insect to essential oil and the higher concentration of essential oil, increased mortality of the two species in all treatments. There was significant difference among mortality effect of the essential oils. The LC50 value of M. piperita after 24 hours for B. lentis and C. maculatus was 14.62 and 13.70 μl/l air respectively, while the values of LC50 were 92.32 and 95.80 for M. pulegium, 58.43 and 99.94 for Z. multiflora and 63.97 and 65.55 μl/l air for T. daenensis, respectively. The least LT50 recorded was in T. daenensis essential oil with 26.21 and 24.15 hours against B. lentis and C. maculatus, respectively.

Oilseeds such as flax, canola, safflower, soybean and sunflower, which are annual plants, provide the world’s major source of vegetable oils, although the highest oil yield comes from oil-bearing tree fruits. One of the most popular oil seeds is safflower (Carthamus tinctorius L.), which belongs to the Asteraceae family. Due to the ability of this plant to grow in dry and semi-dry conditions, safflower oil has the potential to be a commercially profitable product in Iran. Seasonal populations of safflower capsule flies were studied in Kohgiluyeh safflower farms, Iran, from March to May in 2008 and 2009. Four yellow sticky traps were used to monitor populations of fruit flies in the safflower farms. Traps were checked once a week during the sampling period. The traps were emptied weekly into insect collection vials containing 70% ethanol. Data were analysed with a two-way ANOVA. The relation between abiotic factors and species abundance was analysed with multiple linear regression. The results emphasized that Acanthiophilus helianthi was the most serious pest of safflower under the ecological conditions found in Gachsaran, being present in the field throughout three months of the year (March to May). Chaetorellia carthami was present in safflower fields from March to May, but in significant numbers only during April and May. Terellia luteola was present in safflower fields from March to May and in significant numbers only in late April, it does not seem to be a serious pest in safflower farms under Gachsaran’s ecological conditions.

Safflower fly, Acanthiophilus helianthi Rossi (Diptera: Tephritidae), undergoes four stages (egg, larva, pupa and adult) during its growth and development. In this study, observation showed that the egg’s stage took 1.16 ± 0.00, larva’s stage took 12.02 ± 0.13 and pupa’s stage took 7.03 ± 0.08 days before the emergence of adults. The male adult survived for 21.97 ± 2.69 days, while the female lived 19.19 ± 1.50 days. It was observed that the eggs were laid in a cluster, with a range between 10 – 50 eggs per cluster. The length and width of the individual egg were 1.12 ± 0.03 mm and 0.20 ± 0.00 mm respectively. The percentages of the survived individual larva decreased from the first instar until third instar. In the experiment, the length and width of the larva reached 7.77 ± 0.08 mm and 1.84 ± 0.03 mm respectively. Pupae were observed changing in colour from pale white to dark brown. The length and the width of the pupae observed were 6.78 ± 0.16 mm and 2.90 ± 0.02 mm. The longevity of the adults Acanthiophilus helianthi Rossi was influenced by the diets they consumed, the presence of other individuals, wideness of the areas, differences in time taken within the life cycle (between different stages) and temperature in the laboratory.

The present research conducted to see the biodiversity of insects in warm and cool areas from March to April in 2009 at the Gachsaran Agricultural Research Station. A total number of 4261 specimens, which were identified into 31 families and 92 species. Out of total 31 families collected, 10 families were pests, 2 families belongs to predators and beneficial insects and 7 families belongs to parasitoids and beneficial insects and finally, 12 families of insects are saprophage and polyphagous. There was no significant difference (P>0.05) in the number of insects collected between months. The mean number of insects collected in the month of March, April and May was 34.7, 30.7 and 36.2 respectively. The Basht area is most susceptible host for insects (37.9), while the Gachsaran and Lishter areas is less susceptible (33.5) and (28.4) so both sites not differ significantly in the population of insects. The family Coccinellidae had more population in the Gachsaran-safflower zone (98.3) than the Basht-safflower zone (54.6) and it was significantly similar to the family cicadellidae. Similarly, different families like Aphididae (98.0), Cicadellidae (74), Thripidae (50.0), Curculionidae (26.6), Noctuidae (25.0) and Torymidae (27.3) had higher population in the Gachsaran-safflower zone than in the Basht-safflower area with means of 92.3, 63.0, 42.6, 21.0, 21.6 and 19.3 respectively. Also the families like Nymphalide, Pieridae, Lygaeidae, Papilionidae, Miridae, Pentatomidae, Reduviidae, Geometridae, Gryllotalpidae, Mantidae, Acrididae, Saturnidae and Anthocoridae had mean population of 12.6, 7.4, 12.0, 4.1, 4.4, 8.6, 1.9, 0.5, 7.5, 2.4, 11.3, 3.3 and 8.9.

Antifeedant activity of plant extract from Mentha piperita was tested against the cowpea seed beetle, Callosobruchus maculatus. Dry ground plant was subjected to hydrodistillation using a Clevenger-type apparatus. The resulting oil contained menthone (28.9%), menthol (28.5%), and pulegone (6.9%) as the major compounds. LC50 of M. piperita essential oil was 25.70 μL/L air and mortality increased as the doses of essential oil increased. LT50 values were 3.29, 2.74 and 1.89 h at 100, 200 and 500 μL/L air, respectively. The results of persistence test of oil revealed that essential oil of M. piperita on C. maculatus adults was 5.44 days. It was clear from the repellency index that M. piperita essential oil has strong repellency at 90, 180 and 360 μL/L air concentration. The results showed that M. piperita essential oil has significantly affected the relative growth rate, relative consumption rate and feeding deterrence index of C. maculatus adults and it was concentration-dependent. The efficiency of conversion of ingested food has decreased while the concentrations are not statistically different at 5% level compared to the control group. It seems that essential oil can be used as low-risk insecticides.

The lentil weevil, Bruchus lentis Frӧlich, (Coleoptera: Chrysomelidae: Bruchinae) is the most serious pest of lentil in Iran. Economic losses due to this pest reach up to 40% of the lentil crop. Over a two-year study (2012 and 2013) in Agricultural Research Station of Gachsaran Region, best timing of chemical control of B. lentis was determined. A field experiment with cultivation of lentil Sina variety Lens culinaris Medik was conducted in a randomized complete block design with five treatments and three replications. The treatments consisted of spraying four times (respectively, during the early flowering, 10 days after the first spraying, 10 days after the second spraying; 10 days after the third spraying) and control (without spraying). For the spraying from Endosulfan insecticide EC50% at ratio one liter per hectare was used. Three samples were taken from the pods and totally 150 pods from each replicate for contaminations of seeds were investigated. After the determination of the percent of seeds contamination, results were statistically analysed. Based on the results obtained, first spray treatment, with the mean contamination of 15.45% and second spray treatment with the mean contamination of 12.25% had the highest impact on reducing contamination lentil seeds to B. lentis and between them there was no statistically significant difference and were in one group. Therefore, spraying one time during the early flowering until 15 days after it was the best time to control of B. lentis.

Antifeedant activity of plant extracts from Mentha piperita L. and Mentha pulegium L. were tested against the Indian meal moth, Plodia interpunctella (Hübner). The nutritional indices: relative growth rate (RGR), relative consumption rate (RCR), efficiency of conversion of ingested food (ECI) and feeding deterrence index (FDI) were measured for first-instar larvae (15-d old). Treatments were evaluated using a flour disk bioassay in the dark, at 25±1°C and 60±5% R.H. Concentrations of 0, 0.1, 0.5, 0.75, 1, 1.5 and 2 mL/disk were prepared from each essential oil. After 72 h, nutritional indices were calculated. M. piperita oils were more effective than M. pulegium oils, by significantly decreasing the RGR, RCR and FDI. At the highest concentration tested (2 mL/disk), the ECI (9%) was significantly reduced.

The safflower fly, Acanthiophilus helianthi Rossi, 1794 (Diptera: Tephritidae) is one of the most important pests of safflower in Iran. Losses caused by larval feeding leads to disrupted plant activities, reduction in flower buds, and, ultimately, to decreased quality and quantity of crop. An investigation was made from March 2008 to August 2009 in Gachsaran and Yasooj to record the pest status of safflower and their natural enemies. A total of twenty arthropods were recorded as pests of safflower. Out of 25 farms surveyed, only seven had the incidence of pest attack. Among the pests, Safflower fly and Silver ‐ Y‐ moth were found to cause considerable damage to the safflower plants, while others were not at economic levels. Among the natural enemies, parasitoids like Bracon hebetor , Bracon luteator , Colotrechnus viridis , Antistrophoplex conthurnatus , Microdontomenus annulatus , Ormyrus orientalis , Eurytoma acroptilae , Pronotalia carlinarum , Pteromalus sp. and Isocolus tinctorious were found to be associated with the pests of safflower .

Safflower fly, Acanthiophilus helianthi Rossiis is one of the most important pests of safflower in most parts of the country. Losses caused by larval feeding lead to disrupted plant activities, reduction in flower buds and ultimately decreased quality and quantity of the crop. In order to study seasonal flight activity of Acanthiophilus helianthi, experiments were conducted for two consecutive years at two different fields in Gachsaran region in 2007-2008. The seasonal flight of Acanthiophilus helianthi was investigated by using Baits traps and collecting samples from eggs, larva and pupa stages of the pest. The results showed that Acanthiophilus helianthi has three generations with an incomplete 4th in the region. Damage of first and fourth generation was very low. The flower heads were mainly damaged by the second and third generation of Acanthiophilus helianthi that happened about ten days after the adult emergency.

The citrus leaf miner, Phyllocnistis citrella Stainton (Lep., Gracillariidae), is one of the most destructive pest of citrus and related Rutaceae and ornamental plants in Iran. Larvae damage leaves by creating serpentine feeding mines, which have been lead to reduce yield. Resistance and toxicity problems derived from synthetic insecticides have made it necessary to find more effective and healthier alternatives; therefore, bio-insecticides (i.e., Bacillus thuringiensis) are becoming an important component in plant protection. The aim of the present study was to evaluate the efficiency of B. thuringiensis against P. citrella. Eight B. thuringiensis concentrations were used against P. citrella L3 on orange and mortality was recorded at 1, 4, 7 and 10 days after spraying. The results showed that B. thuringiensis significantly affected mortality of P. citrella. After 1, 4, 7 and 10 days of spraying 108 concentration of B. thuringiensis had significantly caused the highest mortality to the pest with 59.8, 68.4, 73.6 and 77.0%, respectively. Then the mortality percent decreased until it reached 6.5, 9.5, 39.3 and 46.7% at 101 concentration, respectively. In conclusion, the study indicated that B. thuringiensis is effective in controlling P. citrella under laboratory conditions.