Qualitative assessment of Caspian kutum (Rutilus frisii kutum Kamensky 1901) stocks in Iranian waters of the Caspian Sea (1991-2011)

The main objective of the present study was qualitative assessment of Caspian kutum (Rutilus frisii kutum Kamensky 1901) stocks by using indicators of overfishing, condition factor and relative weight in Iranian waters of the Caspian Sea during a long period (1991- 2011). Three fisheries indicators in catch were: 1) percentage of mature fish, with 100% as target; 2) percent of specimens with optimum length, with 100% as target; and 3) percentage of mega-spawners, with 0% as target, and if no upper size limit exists, 30-40% as representative of reasonable stock structure. Over this period, the condition factor and relative weight had a decreasing trend. The range of length with optimum yield was between 40 and 48 cm. The mega-spawner measured as fish a size larger than 48 cm. According to these three indicators, the percentage of mature (fork length>40cm), optimum size and mega-spawners were 62.0, 40.9 and 12.5% in 1991-92 which decreased less than 50, 38.2 and 8%, in the years 1992-2011, respectively. The length structure is a matter of concern. Therefore, for reservation and rebuilt of kutum in the Caspian Sea, the target was to let all (100%) fish spawn at least once, using bigger mesh size in cod end (e.g. 35mm, during whole fishing season). The aim was also to implement a fishing strategy that result no (0%) mega-spawners being caught, and the main catch focus on optimum length

Investigation the Different Levels of Drought Stress on Almond Cultivars

Introduction  Water shortage is very frequent in many countries, and, together with the rising demand for industry, growth of human population, climate change and specifically the trend towards irrigated agriculture, has led to widespread problems of water scarcity, especially in Middle East countries. This situation imposes the need to optimize water use in all human activities. Among the different productive uses of water, agriculture is by far the main water user in most water scarce regions and, consequently, any potential improvement in the use of the available water resources may play a significant role toward achieving a more sustainable use of water. Plant responses to water deprivation are usually monitored through selected morphological and physiological parameters which have been proven to be good indicators of drought in different studies. Some of the most important standards for evaluating plant genotypes under drought stress are measurements of morphological parameters such as height, leaf characters and root growth.   Materials and Methods  To compare the growth response of different almond cultivars to different levels of water stress, an experiment was conducted as a split plot in the base of randomized complete block design with three replications in the Agricultural and Natural Resources Research Center of Chaharmahal and Bakhtiari Province in two growing season 2019-2020 and 2020-2021. Different irrigation periods based on the percentage of usable soil moisture between filed capacity to wilting point, including 70% filed capacity (control or no stress), 50% filed capacity (mild stress), 30% filed capacity (medium stress) and 10% of field capacity (severe stress) were considered as the main factor of the experiment. The sub-factor included 14 commercial cultivars of almonds (Mamaei, Rabi, Saba, Araz, Eskandar, Aidin, Shahrood 6, 7, 8, 10, 12, 13 and 21 and GN vegetative rootstock), all of which were grafted on GN rootstock. In this study, uniformly grafted seedlings in terms of age, stem diameter and height were selected and planted. In the second year after planting the seedlings, in order to apply drought stress, tubes for hygrometer (TDR) were installed in each experimental plot and based on soil moisture content, irrigation cycle was determined for different treatments.   Results and Discussion  In both years, three months after applied water stress growth traits and nutrient concentrations in the leaves of treated seedlings were measured. Based on the results of analysis of variance, the morphological traits of almond seedlings were significantly affected by cultivar type and drought stress level. In all almond cultivars, the highest height was belonged to seedlings that were grown in non-stress conditions and with increasing the drought stress intensity, the height of almond seedlings was decreased. Under severe drought stress, GN and Mamaei cultivars had the highest (183.93 cm) and the lowest (94.60 cm) height, respectively. Seedling height in GN, Shahrood 12, Saba and Shahrood 10 cultivars showed the lowest decrement under severe drought stress. In all cultivars, drought stress caused a significant reduction in the length and width of the seedlings crown, and the greatest decreasing was recorded in severe drought stress (10% FC). Under severe drought stress, cultivar GN had the largest crown and cultivars Rabi, Shahrood 7 and Eskandar had the smallest crown. Increasing the drought stress intensity significantly reduced the branches growth of seeding in terms of number and length of sub-branches. As the intensity of drought stress increased, the length of sub-branches decreased however the number of intermediates in sub-branches increased. In non-stressed condition, the cultivar GN had the longest branch (55.95 cm), which was significantly higher than the other studied almond cultivars. The shortest branches were also observed in Saba (29.94 cm) and Eskandar (29.47 cm) cultivars. Increasing drought stress caused a significant reduction of leaf area in all studied cultivars and the highest decreasing was observed under severe drought stress. The GN (37.76 cm²) and Shahrood 10 (31.81 cm²) had the highest leaf area in non-stress and drought stress conditions. Under severe drought stress (10% FC) cultivar Shahrood 6 showed the lowest leaf area. The results of this study showed that increasing the intensity of dehydration significantly reduced the amount of nitrogen, phosphorus, manganese and zinc in the leaves of the studied cultivars of almonds, however, the amount of potassium and iron in stressed plants increased under drought stress. Based on the results of the present study, under severe drought stress the GN, Shahrood 8 and Shahrood 12 cultivars in terms of growth indices including seedling height, stem diameter, canopy growth, branch growth and concentration of macro and micro elements was superior compared with the other studied cultivars.   Conclusion  Based on the results of this study, drought stress significantly reduced growth indices and nutrient concentrations, although the reaction of almond cultivars to different levels of drought stress was different. In this study, among the studied almond cultivars GN, Shahrood 8 and Shahrood 12 cultivars in terms of growth characters including seedling height, stem diameter, canopy growth, branch growth and concentration of macro and micro elements showed higher tolerance to different level of drought stress. These cultivars less affected by the high intensities of dehydration. Therefore, GN, Shahrood 8 and Shahrood 12 cultivars can be used in future studies to evaluate the possibility of cultivating these cultivars in areas with water deficit

Biology and demography of Trissolcus basalis (Hym.: Scelionidae) on eggs of two different hosts

A study was taken up to investigate the biological and population attributes of Trissolcus basalis (Wollaston) on eggs of Eurygaster integriceps Puton (EI) and Graphosuma lineatum (L.) (GL). First, immature development, time of adult eclosion, offspring sex ratio and rate of emergence were recorded by random selection of 25 parasitized egg masses of each host (350 eggs with 0-4 h old) separately at 25 ± 0.5 °C, 65 ± 5% RH and 16: 8 L: D. In addition, percent parasitism, immature survival rate, adult longevity and first 10 days fecundity of females were calculated using 25 newly emerged pairs (0-4 h) confined in tubes and provided with two masses of respected host eggs daily under the same conditions till they died. Results revealed that T. basalis males had significantly shorter development period (11.75 ± 0.058 and 12.57 ± 0.96 d on EI and GL eggs, respectively) compared to that of females (12.62 ± 0.06 and 13.72 ± 0.69 d on eggs of EI and GL, respectively). Similarly, it was noticed that malesâ longevity (54.72 ± 1.63 d) on EI eggs was significantly higher compared to their sibling females (43.16 ± 2.045 d) and male and female wasps on GL eggs which had significantly shorter longevity. In general, T. basalis reared on EI eggs had significantly longer oviposition period (39 ± 1.79 d), higher fecundity (292.4 ± 11.14 egg/female) and greater % parasitism (84.09 ± 1.56%) when compared with those on GL eggs. Moreover, immature survival rate was 82 and 64 % for wasp reared on EI and GL eggs, respectively. Finally, rm, λ and R0 were 0.316 and 0.224 d-1, 1.372 and 1.252 d-1 and 118.5 and 51.08 f/f/gen for wasps on EI and GL eggs, respectively. The population age distribution demonstrated that, totally, 95-98 and 2-5 % of the population were immature and adult stages for both hosts

Study and relocation of corals in developing area of Shahid Beheshty port, Chabahar

The conservation of coral colonies is very vital for marine organisms and human. In Chabahar Bay, the coral reefs are in danger of destruction due to the development program of Shahid Beheshti Port. In this project, over 30,000 hard corals were transported to coast of Hotel Lipar an area at a distance of 3.5-4 kms far from Shahid Beheshti Port. Also, the new techniques were used for coral reattachment and transportation. The operation has done within expert divers and consultancy of Prof. Dr. Maikle Risk. Four methods performance as pailots. Since the corals are very sensitive to turbidity and suspended sediments from land reclamation and dredging projects, therefore appropriate measures should be conducted for conservation and recovery of them.37 patches in size 5×10 meters has built with concerete. Diffent sizes of corals were separated by mechanical tools and transported to new sites and reattachment on artificial sea bottom.Three monthes after the last reattachments monitored showed that %96.93 of corals were in good health. This success was the important achievement because of innovating coral carrier and mass coral relocation. At present, the coral relocation is suggested as a good method for recovery of coral reefs after a disturbance in condition of their native habitats

An ecological investigating on controlling Mnemiopsis leidyi population activity 6: molecular test in identification of Mnemiopsis leidyi

In this study population genetic structure of Mnemiopsis leidyi were examined by 200 samples from the Caspian Sea. Samples were collected from Guilan province (Astara region), Mazandaran province (Amir Abad region), Golestan province (Gomishan region) and north part of the Caspian Sea. 50 samples were collected from each region. DNA was extracted by phenol - chlorophorm method and its concentration was 50 to 100 nanogram. PCR was performed using 18s rRNA gene. The PCR products of samples were digested by 12 restriction endonuclease enzymes. The digested products accompanied with standard marker (50 bp lader ). In order to measure fragment size samples were run on a 6% vertical polyacrylamide gel. The fragments were visualized by silver staining of the polyacrylamide gel. In this study, Dra I and Alu I enzymes showed different digestion pattern, as each of these enzymes had two genotypes. Other enzymes had similar digestion pattern. RAPD method used by 19 random primers. Ten of nineteen primers showed polymorphism patterns. Statistical analysis of data was performed by Popgene software. In this study, the maximum of genetic variation was in north of the Caspian Sea. Also, the maximum of genetic distance was between north area and Golestan coasts (0.089) and the minimum of genetic distance was between Mazandaran and Guilan coasts (0.001). The UOGMA dendogram showed two clusters. The samples of Mazandaran , Guilan and Golestan coasts placed in one cluster and samples of north area in other cluster The genetic diversity was significantly different between samples of north area and Golestan coasts (p≤0.05). As result, there is a significant genetic divergence between some of samples. Therefore, two genetic group of Mnemiopsis leidyi were identified in the Caspian Sea

Study on the growth status of mullets with viral nervous necrosis disease in the southern Caspian Sea

Mullet and mullet products have considerable economic importance at a regional level, especially around the Caspian Sea. The leaping mullet constitutes an important part of their production. This study is the first detailed work on the age and growth of the leaping mullet (Liza saliens) from September 2012 to March 2013 in the Southern coast of the Caspian Sea. Age and growth determinations were based upon the scale samples taken from 102 fish. Marginal increment analysis was used to validate age determination. The back-calculated lengths stage estimated from the scale showed no differences between in this study. The maximum age of leaping mullet in the Southern coast of the Caspian Sea was 5 years for males and 6 years for females. The von Bertalanffy growth functions were Lt=30.415(1-e-0.275(t+0.645)) for males and Lt=34.832(1-e 0.211(t+1.009)) for females. A large spread and length overlap characterized the age groups. The estimated Length Weight relationships were common for the two sexes (W=0.079L3 ). The slope (b) values of the length-weight relationship showed that weight of leaping grey mullet in Mazandaran increased associated with length in isometric. The mean condition factor for males, females and all specimens were determined as 0.908, 0.900 and 0.897, respectively. According to sex groups, the mean condition factor of males was slightlyhigher than that of females. The total length for leaping grey mullet was determined as 23.3 cm

Prevalence and correlates of psychiatric disorders in a national survey of Iranian children and adolescents

Objective: Considering the impact of rapid sociocultural, political, and economical changes on societies and families, population-based surveys of mental disorders in different communities are needed to describe the magnitude of mental health problems and their disabling effects at the individual, familial, and societal levels. Method: A population-based cross sectional survey (IRCAP project) of 30 532 children and adolescents between 6 and 18 years was conducted in all provinces of Iran using a multistage cluster sampling method. Data were collected by 250 clinical psychologists trained to use the validated Persian version of the semi-structured diagnostic interview Kiddie-Schedule for Affective Disorders and Schizophrenia-PL (K-SADS-PL). Results: In this national epidemiological survey, 6209 out of 30 532 (22.31) were diagnosed with at least one psychiatric disorder. The anxiety disorders (14.13) and behavioral disorders (8.3) had the highest prevalence, while eating disorders (0.13) and psychotic symptoms (0.26) had the lowest. The prevalence of psychiatric disorders was significantly lower in girls (OR = 0.85; 95 CI: 0.80-0.90), in those living in the rural area (OR = 0.80; 95 CI: 0.73-0.87), in those aged 15-18 years (OR = 0.92; 95 CI: 0.86-0.99), as well as that was significantly higher in those who had a parent suffering from mental disorders (OR = 1.96; 95 CI: 1.63-2.36 for mother and OR = 1.33; 95 CI: 1.07-1.66 for father) or physical illness (OR = 1.26; 95 CI: 1.17-1.35 for mother and OR = 1.19; 95 CI: 1.10-1.28 for father). Conclusion: About one fifth of Iranian children and adolescents suffer from at least one psychiatric disorder. Therefore, we should give a greater priority to promoting mental health and public health, provide more accessible services and trainings, and reduce barriers to accessing existing services. © 2019 Tehran University of Medical Sciences. All rights reserved