نورالدین شایسته

The Khapra beetle is one of major pest of stored products, specially wheat and barley. The present research was conducted to study the applicability of microwave radiation at specified power rates and exposure times to control.
Each developmental stage was exposed to 2450MHZ at power levels of 300, 400 and 500W for 3 and 4 min. Experiments were arranged in completely randomized deign with 3 replications. After treatment, samples were kept under constant conditions in an incubator at 35±1 C and 70±5% R.H and 16D: 8L photoperiod. The most effective radiation to reduce the egg hatching rate, to induce mortalities in larvae, pupae and adults was the power rate of 500W and exposure time of 4 min. The order of sensitivity of different developmental stages was egg, last- instar larvae, adult, pupa and first-instar larvae.The result also revealed a direct relationship between exposure time at constant power led in increase in mortality of the insects. 1-2 days old eggs were more resistant than 0-1 and 2-3 days old eggs. A low power rate resulted decreasing oviposition rate and loss of tails in first-instar larvae .Based on the results the 500W and exposure time of 4 min. can be recommended for control of the Khapra beetle.

Potato, Solanum tuberosum L. is an important crop with 5.24 million tons of production on 210,000 hectares of irrigated land in Iran. Several pests attack the potato crop which among them the Colorado potato beetle, Leptinotarsa decemlineata (Say), is the most important defoliating pest of potato throughout the world and Iran and considerably reduce crop yield. Growers rely on pesticides to control this pest in the field but this insect is well known for its rapid resistance development to pesticides, so that it has developed field resistance to nearly all insecticides used against it and it is now resistant to more than 40 chemical insecticides. The problems of insecticide resistance, combined with continuing environmental concerns associated with chemical pesticide use, have provided a considerable stimulus over the past 50 years for the development of alternative control methods. Host plant resistance is considered to be an important part of integrated pest management (IPM) system of this pest, which is compatible with sustainable control methods and can reduce the use of chemical insecticides .With the aim of identifying the existence of resistance resources, a study was conducted to evaluate and comparison the resistance index (PRI) of 33 potatocultivarsto the Colorado potato beetle. Detected resistant variety (ies) could be used as a resistance source for IPM programs of this pest.
Greenhouse and field experiments were conducted to compare resistance index (PRI) of 33 potato cultivars to the Colorado potato beetle, Leptinotarsa decemlineata (Say), in Naghadeh region during 2007-2008. In a choice test, the numbers of attracted beetles to each cultivar was determined as antixenosis index in the field. Also, Percentage of larval and pupal mortality were determined and used as the antibiosis index under greenhouse conditions. To evaluate the tolerance index, infested and non infested plots were planted and arranged based on a randomized complete block design under field conditions. In infested plots, each plant was infested by 40 medium larvae (second and early third instars) 15 days prior to the blooming of plants. At the end of season, yield loss in infested plots were determined and compared with non infested plots for each cultivar and used as the tolerance index. Normalized values for each category were computed on a zero-to-one scale by dividing the mean value of each variety evaluated by the maximum mean value of all entries. Normalized tolerance values were calculated as percent reductions of plant biomass relative to a non-infested control. Normalized indices for antibiosis (X), antixenosis (Y) and tolerance (Z) were used to calculate PRI in the formula: PRI = 1/(XYZ) (Inayatullah et al., 1990).
Combined analysis of variance showed that interactive effect of cultivar × year was significant for all of the indices at P=0.01. The cultivars Sinja, Bridjet and Cardinal with the least antixenosis index (Y), had the highest antixenosis resistance to the Colorado potato beetle in 2007, also the cultivars Cardinal, Carlita and Elles with the least antixenosis index (Y), had the highest antixenosis resistance to the pest in comparison to other cultivars in 2008. The highest antibiosis (X) resistance was observed in the cultivars Delikat, Carlita, Armada and Sinja with the least antibiosis index, in two studied years. The cultivars Satina, Cardinal, Santana and Nicola with the least tolerance index (Z), had the highest tolrence to the Colorado potato beetle in comparison to the other cultivars during 2007-2008. The cultivars Delikat,Bridjet and Cardinal ere the most resistant cultivars with 52.63, 36.30 and 29.87 PRI, respectively in 2007. In this year, the cultivars Diamont, Aparet and Velox were the most sensitive cultivars with 1.90, 2.06 and 2.26 PRI, respectively in comparison to other cultivars. In 2008, the cultivars Santana, Bridjet and Sinja were the most resistant cultivars with 48.56, 28.36 and 25.80 PRI, respectively and the cultivars Velox, Agria and Bright were the most sensitive cultivars with 1.90, 2.71 and 3.20 PRI, respectively in comparison to the other cultivars in 2008.
Significant positive correlation was observed between the plant resistance indices (PRI) in two study years (r= 0.499, P= 0.01). Results of this research revealed that the cultivars Bridjet, Delikat, Cardinal, Carlita, Sinja and Nicola with the highest PRI were the most resistant cultivars to the Colorado potato beetle in comparison to other cultivars during 2007-2008, suggesting that these cultivars can be used in the IPM program of the pest and resistance transfer to high yield varieties through plant breeding programs.

West Azerbaijan Province is a mountainous area in the North West of Iran that has a high potential for the production of grains/cereals. The diversity of active aphids species and their coccinellids predators in wheat farms of this province was studied for two years during 2010 and 2011. The present study identified six harmful species of aphids and five species of ladybird beetles being their main enemies at different wheat growth stages and different sampling dates. In 2010, Schizaphis graminun (Rondanii) species was the most frequently found species and was considered as dominant species in the area. The highest species richness of the collected grains/cereals aphids was recorded five species in the early of May in 2010. The highest degree of Shannon diversity index (1.81) was also related to 2nd of May, 2010 and the least amount of the same index (0.65) was found in 1st of July in the same year. In 2011, Metopolophium dirhodum (Walker) species had the most frequency rate and was regarded as the dominant species. The highest species richness of the collected aphids of the grains was observed during the mid-June in 2011. The highest degree of Shannon diversity index (1.25) was related to 15th of April 2011 and the least amount of the same index (0.81) was found in 11th of March in that year.

In this research, the biological and nutritional indices of Colorado potato beetle, Leptinotarsa decemlineata (Say), were evaluated on 33 potato cultivars in greenhouse conditions. Tubers of cultivars were planted in pots and on each pot one sleeve cage were set up, in which 5 newly emerged female adults were released and the weight of them was measured on the 10th day after releasing. In another experiment, 15 first instar larvae were released on each pot and reared. Amounts of consumed foliage of treatments, larval weight on the 12th day after releasing, duration of larvae and pupae (immature stages) and mortality percentages of these stages were determined. Significant differences were observed for all of the studied traits at 1% level. The highest weight of reared adults was observed on the ‛Sinja’ and‛Bright’ cultivars. The least amount of foliage consuming by larvae was observed on the ‛Satina’ and‛Santana’ cultivars. The least weight of neonate larvae on 12th day after releasing was observed on the ‛Myryam’ and‛Carlita’ cultivars. The longest developmental time (larval and pupal time) on potato cultivars was on the ‛Bridjet’ and‛Delikat’ and the highest larval and pupal mortality were on the ‛Arrancar’ and‛Agata’ cultivars. The least weight of female adults, produced from reared larvae, was observed on the ‛Delikat’ and ‛Romina’ cultivars and the least weight of male adults was observed on the ‛Romina’ and‛Delikat’ cultivars. This research revealed that larval preference is independent from nutritional preference of adults.

Organic agriculture, sometimes called biological or ecological agriculture, combines traditional conservation-minded farming methods with modern farming technologies .The purpose of this research was to identify management skills in development of Organic Agriculture in West Azerbaijan Province (Iran) farms. The target population of this research included all agricultural experts who work in West Azerbaijan Province. By using a Cochran formula a number of 200 agricultural experts selected as statistical sample. The research instrument was a structural questionnaire including close-ended questions which its validity was confirmed by using expert panel and reliability by Cranach’s alpha test (α= 0.89). According to the results of the factor analysis finding shows that six factors included the skills of using methods and technologies of organic agriculture, informing skills, farming skills, and production skills involved 51.46 % of the total variance and played crucial roles in in development of organic agriculture in the West Azerbaijan Province farms. Among these factors, the factor of using methods and technologies of organic agriculture involved 12.44% of the total variance and played a more important role in using the management skills in development of organic agriculture in West Azerbaijan province Farms.

In this research، the host preference and life cycle of the Colorado potato beetle، Leptinotarsa decemlineata (Say)، was studied on 33 potato cultivars. Significant difference was observed for all studied traits (P>0. 05 & P>0. 01). The lowest number of adults was attracted to cultivars Raja، Carlita and Bridget with mean values of 0. 33±0. 17، 0. 50±0. 29 and 0. 50±0. 29 adults، respectively. The lowest egg masses were observed on Bright، Bridget and Raja with means values of 1. 00±0. 00، 1. 50±0. 29 and 1. 50±0. 29 egg masses per hill، respectively. The longest larval and pupal developmental times were observed on Satina، Idol and Eba with mean values of 36. 57±1. 19، 36. 25±0. 89 and 35. 58±1. 23 days، respectively. The highest larval and pupal mortalities were observed on Delikate، Carlita، Armada، Raja and Bridget with mean values of 91. 11±2. 22، 88. 89±2. 22، 84. 45±2. 22، 80. 00±3. 85 and 80. 00±7. 70 percent، respectively. The longest life cycle times of pest (egg to adult) were observed on Idol، Satina and Elles with mean values of 42. 91±0. 37، 42. 62±1. 40 and 42. 17±1. 27 days، respectively. Therefore، it was concluded that among the 33 cultivars studied in this research، cultivars Bridget، Raja and Bright were the least suitable cultivars for the Colorado potato beetle and they can be used in the IPM of the pest.

Colorado potato beetle, Leptinotarsa decemlineata (Say), is the most important defoliating pest of potato throughout the world and Iran which considerably reduce crop yield. In this study tolerance of 33 cultivars of potato were compared during 2007-2008 in the field conditions. Experiment was carried out in both years in two trials, infested and non infested plots and arranged based on a randomized complete block design. In infested plots, each plant was infested by 40 medium larvae (second and early third instars) 15 days prior to the blooming of plants. Non-infested plots were kept pest-free by chemical and mechanical control methods. At the end of the season, defoliation and yield loss in infested plots were determined and compared with non-infested plots in each cultivar. Cluster analysis of cultivars was performed with MINITAB15 statistical software using UPGMA procedure based on Euclidean distance. Combined analysis of variance of tolerance data in 2007 and 2008 showed significant differences among the cultivars (P < 0.01). Moreover, for all studied traits reciprocal effect of cultivar × year was significant (P < 0.05). Cluster analysis based on defoliation and yield loss in two experimental years showed that cultivars “Santana”, “Satina”, “Bridjet” and “Cardinal” had the highest tolerance to the Colorado potato beetle. Significant positive correlation was observed between yield loss and defoliation traits in two years of study (P<0.01).

The Colorado potato beetle, Leptinotarsa decemlineata (Say), is a serious pest of potato, Solanum tuberosum L. worldwidely. One of the methods used for controlling of it is deployment of resistant cultivars. Field experiments were conducted to evaluate the antixenosis resistance in 33 potato cultivars to this pest during 2007 - 2009. Research method in 2007 was similar to 2008 and was different from 2009. In a field choice test, the numbers of attracted beetles to the cultivars were determined as antixenosis index. Numbers of attracted beetles to the cultivars and numbers of egg masses on them were used as antixenosis indices during 2009. Cluster analysis of cultivars was performed with MINITAB15 statistical software using UPGMA procedure based on Euclidean distance. Combined analysis of variance of choice test data in 2007 and 2008 showed that with point of settled adult beetles on the studied cultivars, significant difference was observed between experimental years, blocks, times of counting, cultivars and reciprocal effect of cultivar × year (P < 0.0001). Mean comparison showed that cultivars Bright, Delikat, Nicola, Sinja, Carlita and Cardinal in 2007 and Cardinal, Carlita, Sinja, Elles and Romina in 2008 had the highest antixenosis resistance with the least settled adult beetles on them. Cluster analysis showed that in two first years, cultivars Cardinal, Carlita, Sinja, Bright, Raja, Nicola, Romina, Santana, Elles, Fianna and Satina with the least attracted beetles were resistance group in antixenosis index. Also, cluster analysis based on the number of attracted beetles to the cultivars and number of egg masses on the cultivars showed that cultivars Bridjet, Baltica, Cardinal, Nicola, Raja, Bright, Delikat, Carlita, Provento, Cosima, Armada, Elles and Beluga were placed in one group and had the highest antixenosis effects compared to others cultivars in 2009. Mean comparison showed that cultivars Cardinal, Carlita and Bridjet had the highest antixenosis resistance with the least settled adult beetles on them in three experimental years.

Life table of almond moth, Cadra cautella Walker was studied on four main dry and semi-dry date palm varieties (Deyri, Zahedi, Piarom, and Rabbi) of Iran under laboratory conditions. Data were analyzed based on the age-stage, two-sex life table theory. Duration of total preadult stages was 42.54, 45.79, 51.48 and 50.41 days on Deyri, Zahedi, Piarom, and Rabbi, respectively. The highest fecundity of female almond moth on date palm varieties was 245.29 eggs on Zahedi. The intrinsic rate of increase (rm) on different varieties of date palm ranged from 0.069 d-1 (on Piarom) to 0.105 d-1 (on Deyri). The highest net reproductive rate (R0) was on Deyri (95.81 offspring) and the lowest value was on Rabbi variety (42.37 offspring). Our results showed that the highest rm, the largest fecundity and the shortest generation time of almond moth were observed on Deyri variety. It was concluded that among date palm varieties, Deyri was the most favorable host plant for almond moth reproduction performance.

The postharvest pests، including the dried fruit moth Cadra cautella Walker، are important limiting factors in the exportation of dates. The biology of C. cautella، its survivorship، developmental time، fecundity، oviposition، post oviposition period، as well as longevity of the adults were studied on four date palm varieties of Zahedi، Piarom، Rabbi، and Deyri under laboratory conditions in Iran. The experiments were carried out at constant temperature room (29 ± 1 °C، 60 ± 5% RH and photoperiod 16L: 8D hrs.). The highest survivorship of egg and larval stages was recorded 92. 66%، 85. 89% on Zahedi and 100% for pupal stage on Rabbi. The shortest larval period was 32. 93 ± 1. 41 days and 33. 37 ± 1. 87 days on Deyri and Zahedi respectively. The shortest total development time for males from egg to adult was 40. 91 ± 1. 15 days and 40. 97 ± 1. 59 days on Zahedi and Deyri respectively and for females was 43. 76 ± 2. 47 days on Deyri. The longest total development time for males was 47. 61 ± 1. 50 days on Piarom and for female was 55. 88 ± 2. 31 and 55. 37 ± 3. 87 days on Piarom and Rabbi respectively. The highest (247. 00 ± 8. 53 eggs per female) and lowest (147. 40 ± 12. 06 eggs per female) fecundity occurred on Zahedi and Piarom، respectively. The date palm varieties Zahedi، Deyri، Rabbi and Piarom are found to be on preferrence order for C. cautella. The results of this study would be useful for planning pest management strategies in date palm fruit storages.

Greenhouse and field experiments were conducted to evaluate the resistance components in 33 potato commercial cultivars to Colorado potato beetle, Leptinotarsa decemlineata (Say) in 2008. In a field choice test, the numbers of attracted beetles to the cultivars was determined as antixenosis index. To evaluate the antibiosis, potato tubers were planted in pots under greenhouse conditions and on each pot, one sleeve cage was set up, in which 15 first instar larvae were released and reared. The Larval weight after 12 days of releasing, mortality percentages of larvae and pupae and the durations of developmental stages were analyzed as the antibiosis indices. To study the level of tolerance of cultivars, the infested and non infested plots were isolated and arranged based on a randomized complete block design in field. In infested plots, each plant was infested by 40 medium larvae (second and early third instars) 15 days prior to the blooming of plants. At the end of the season, defoliation and yield loss among infested plots were determined and compared to non infested plots for each cultivar. Significant differences were observed in all studied traits. The cultivars Cardinal, Carlita and Sinja showed antixenosis effects with the least numbers of attracted beetles, whereas cultivars Carlita, Sinja, Delikat, Aparet and Bridjet showed antibiosis effects in comparison to the others. The cultivars Santana, Satina, Nicola and Bridjet showed tolerance to damage of the pest. Using cluster analysis, UPGMA procedure was based on Euclidean distance and 33 experimental cultivars were grouped in 7 distance groups.

Dried fruit moth (Cadra cautella) (Walker) is one of the most important pests of dried fruits and was reported on dried date, dried fig and raisin from Iran. The biology of this pest has not been studied on dried fruits products of Iran, regardless of economic value of this pest. In this research some biological characteristics including development time, fecundity and survivorship of C. cautella on dried fig, dried berry, dried date and raisin were investigated. All experiments carried out at constant temperature room (29±1 °C, 60 ± 5% RH and Photoperiod 16L: 8D). Based on the results, the highest (251.38±16.51) and lowest (177.83±15.25) fecundity occurred on the dried fig and raisin respectively. Shortest and longest development time from egg to adults for female was occurred on dried fig and raisin respectively. Also, the highest (91.52±3.16%) and lowest (83.23±2.83%) survivorship of immature development stages of C. cautella were observed on dried date (Zahedi variety) and raisin respectively. Thus dried fig and dried date (Zahedi variety) are preferred by C. cautella.

Lasioderma serricorne (Fabricius) is one of the damaging agents in all producing stages of tobacco, from processing to cigarette, in almost all over the world. To control this pest in Iran every year costly fumigation programs are carried out which sometimes cause hygienic problems for fumigation workers too. In this study four tobacco storages in Sari, Bandar-e-Torkman (2 stores), and Gorgan (totally 15575 m3) were fumigated with current recommended phosphine fumigation doses. That is, one 3-gram Phostoxin® tablet (Degesch; Germany) was used to fumigate every m3 of bales and tobacco boxes. For this purpose tablets were put in metal trays over the boxes covered by gas-proof plastic sheet for 96 hours. To investigate the efficiency of fumigation, pheromone traps were employed. Traps were examined from late June through early November every week and the numbers of collected insects were recorded. The results of the study revealed insect control failure in all the storages and insects had been trapped from the second week after phosphine treatment. The reason might be deficiency of current recommendations for fumigations or occurrence of resistance to phosphine due to these regions.

Efficacy of temperature and exposure interval on the toxicity of Silico-Sec®, a diatomaceous earth formulation, was determined on 7-14 days old adults of Rhyzopertha dominica (F.) and Tribolium castaneum Herbst under laboratory conditions at 22, 27, 32 ºC and 65 ± 5% R.H. Insects were exposed for 8-72 hours to diatomaceous earth at the rate of 10 g/m2 on a filter paper inside plastic Petri dishes separately. Then the initial mortality was counted and, to determine delayed mortality, live individuals were held for a week in clean Petri dishes without food at the same conditions of previous experiment. LT50 values of initial mortality for R. dominica were 21, 12 and 9 hours at 22, 27, 32 ºC, respectively, and in the case of T. castaneum, they were 52, 27 and 18 hours at the same temperatures. The LT50 values indicated that R. dominica was more sensitive to Silico-Sec® than T. castaneum under identical conditions. Results indicated that the initial mortality of both species was significantly lower at 22 ºC in comparison with 27 and 32 ºC, and a direct relationship between temperature and exposure period was observed. Mortality percentage of both storage pests was higher after a week than initial mortality. Therefore, Silico-Sec® can be recommended as a structural treatment of stored grain facilities.