Natural Resources Research Center Research Articles

Vermicompost as an alternative substrate to peat moss for strawberry (Fragaria ananassa) in soilles culture

BackgroundConsecutive droughts and quantitative and qualitative reduction of surface and underground water resources have caused an increase in greenhouse and hydroponic cultivation for most garden crops, including strawberries, in Iran. On the other hand, most of the inputs of greenhouse crops in Iran are imported. To possibility of replacing vermicompost with peat moss under hydroponic cultivation, an experiment was done in a split plot based on randomized complete blocks design in three replications in Isfahan (Iran) Agricultural and Natural Resources Research Center in 2019. The main treatment was substrate at four levels included different levels of vermicompost (30 and 50%) and peat moss (30 and 50%) in combination with perlite and sub-treatment were Selva and Camarosa cultivars.ResultsThe results showed that Camarosa cultivar and Selva cultivar in (perlite/ peat moss 50:50) and Selva cultivar in (perlite / vermicompost 70:30) had maximum yield.Leaf number and chlorophyll index were maximum in Camarosa cultivar in peat moss substrates. Strawberry cultivars had the highest root fresh weight, the content of vitamin C and total soluble solids (TSS) in substrates containing vermicompost. Camarosa cultivar in (perlite / peat moss50:50) and Selva cultivar in (perlite /vermicompost 50:50) had maximum root dry weight. Also, the highest number of inflorescences was related to substrates containing peat moss and (perlite /vermicompost 70:30). Maximum amount of fresh and dry weight of shoots were observed in (perlite/ peat moss70:30). Selva cultivar had more inflorescences (16.5%) than Camarosa cultivar and Camarosa cultivar produced more fresh and dry weight of shoots (16.5%, 23.01%) than Selva cultivar.ConclusionExpriment results highlighted the importance of considering both main and sub-treatments in agricultural research, as they interacted to influence various growth and yield parameters. 50% vermicompost treatment combined with perlite had a positive impact on plant growth and in quality index such as vitamin C content and TSS was highest. while the choice of cultivar affected different aspects of plant development. Selva cultivar was known to be more tolerant to salinity caused by vermicompost. Vermicompost is local and more economical, also salt resistant cultivars are recommended in a controlled (30%) amount of vermicompost.

Grain yield and its contributing traits in promising sweetcorn hybrids

AbstractThe augmentation of domestic sweetcorn (Zea mays L. saccharata) production in semiarid regions necessitates the development of new superior hybrids with high yield potential. This study aimed to identify the most influential characteristics contributing to sweetcorn grain yield in these regions. Nineteen promising sweetcorn hybrids and the commercial hybrid KSC403su as the control were examined using a randomized complete block design with three replications in a 2‐year study (2021–2022) at the Khorasan Razavi Agricultural and Natural Resources Research and Education Institute Center (ARREO) in Mashhad, Iran. The combined analysis of variance revealed significant variances attributed to genotype (G) for all studied traits, while year (Y) and G × Y effects were significant for most characteristics. Phenotypic correlations indicated a highly significant association of grain yield with grain depth (r = 0.79, p < 0.01), kernel number per row (r = 0.75, p < 0.01), row number per ear (r = 0.63, p < 0.01), ear length (r = 0.58, p < 0.01), and ear diameter (r = 0.57, p < 0.01) traits. Path analysis results emphasized the critical role of traits such as grain depth, row number per ear, and ear length, showcasing a highly significant positive direct impact on grain yield and also a significantly positive association with grain yield. In this study, hybrids PSM3, PSM4, PSM9, PSM16, and PSM19 exhibited the highest values for grain yield and yield‐contributing traits, suggesting their potential for further research in multiple locations with varying environmental conditions before being recommended to farmers.

Agro-Physiologic Traits of Soybean in Response to Biological Fertilizers

Plant nutrition is one of the most important environmental factors affecting the quantitative and qualitative yield of crops. This study investigated the effect of rhizobium and azospirillum inoculum and foliar application of humic acid and nutrients of molybdenum, cobalt, and boron on node formation, yield, yield components, and morpho-phenological traits of soybean (Saman cultivar). The experiment was carried out in a factorial randomized complete block design at Golestan Agricultural and Natural Resources Research Center in 2018 and 2019 in three replications. The results showed that experimental treatments had a significant effect on the measured traits. Most of the measured traits, including yield, under the influence of seed treatment with bacteria azospirillum and cobalt, molybdenum, boron showed more increase than the control. It was found that under humic treatment, application of bacteria and nutrients can be effective on improvement of seed yield, so the highest seed yield mean (3268 kg/ha) was obtained by humic acid + Rhizobium+Azospirillum + Co+Mo+B treatments. Also, the highest protein yield mean was obtained by humic acid + Rhizobium + Co+Mo+B treatments (1103 kg/ha) and highest mean of oil yield was obtained by humic acid + Rhizobium+Azospirillum + Co+Mo treatments (577 kg/ha). Overall, the results of this study confirmed the efficiency of nitrogen-fixing bacteria as well as foliar application of micronutrients in increasing soybean yield per unit area.

Characterization of dragonhead (Dracocephalum moldavica L.) landraces: Genetic, chemotypic, and agro-morphologic perspectives

Dragonhead (Dracocephalum moldavica L.), an endangered herb, faces significant threats due to the loss of biodiversity driven by land-use change. The seeds of seven landraces of D. moldavica were collected from various native populations in different regions of Northwest Iran. Subsequently, they were cultivated in 10 replications, spanning a total of 70 plots. This cultivation took place at the Ekbatan station of the Agriculture and Natural Resources Research Center in Hamadan province. This study aimed to assess the morphological traits, essential oil (EO) content, and genetic diversity within seven populations of Dracocephalum moldavica. Significant variations in morphological traits were observed among populations, indicating phenotypic diversity and potential for selective breeding programs. The EO content ranged from 0.03 % to 0.13 % (w/w), with the highest in the HO population and the lowest in the KE population. EO yield varied from 1.97 in the KE populations to 13.97 Kg/ha in the HO populations. The chemical composition of the EOs varied among populations and consisted of 18–24 components, with geranyl acetate being the dominant component. PCA analysis identified population differences primarily related to geranyl acetate, nerol, geraniol, neryl acetate, and neral. The observed variation in EO composition may result from genetic and environmental factors. ISSR analysis revealed high genetic diversity, with 84 out of 94 scorable bands being polymorphic. Cluster and PCoA analysis revealed distinct genetic clusters among populations, although some diversities did not align with geographical origin, suggesting seed transfer or high heterozygosity. The study highlights the effectiveness of ISSR markers in assessing genetic diversity and provides insights into the genetic structure and variability of D. moldavica populations. Furthermore, the correlation between ISSR markers and phytochemical traits suggests their potential for breeding programs to enhance important traits in D. moldavica. Considering both phytochemical and morphological properties is crucial in breeding programs due to pleiotropic effects of genetic loci.

Quantitative and Qualitative Yield of Groundnut (Arachis Hypogaea L.) in Response to Intercropping Pattern and Integrated Application of Chemical and Biological Phosphorus Fertilizers

ABSTRACT Intercropping between cereals and legumes can increase resource use efficiency, agricultural productivity, and yield sustainability and reduce chemical inputs. For these reasons, this experiment was performed as factorial arrangement based on randomized complete block design with three replications in experimental station of Guilan Agricultural and Natural Resources Research and Education Center, Rasht, Iran in 2016 and 2017 cropping seasons. Experimental treatments included five levels of phosphorus fertilizer (PF) as triple super phosphate (TSP) including : 1- Zero (as control), 2–50 kg ha-1 TSP, 3–100 kg ha-1 TSP, 4–50 kg ha-1 TSP+200 g ha-1 Barvar2 phosphate bio-fertilizer (BPB) and 5–100 kg ha-1 TSP+200 g ha-1 BPB, and five IPs (IP) including: 1- maize (Zea mays L.) sole cropping, 2- groundnut sole cropping, 3- intercropped groundnut-maize with the ratio of 1:1, 2:1 and 1:2 rows, . Although, maximum grain yield of maize and groundnut was obtained in response to the application of 100 kg ha-1 TSP plus 200 g ha-1 BPB under sole cropping, the highest land equivalent ratio (LER) was observed under zero usage of TSP and intercropped maize-groundnut with the ratio of 1:1 rows. Crops in intercropping system have a complementary effect together. In this experiment, LER values greater than 1.00 indicated an intercrop advantage to sole crop. Results showed that IP increases the quantity and quality of products by increment in plant diversity, ecological balance, more utilization of resources, and reduction of damage by pests, diseases, and weeds in agricultural ecosystems.

Effect of Irrigation Intervals on Some Morphological Traits, Seed Properties and Essence Yield of Savory (Satureja spicigera L.) Under Field Conditions

Agricultural management is one of the main factors to ameliorate environment adverse effects. Climate change has adverse effects on water availability in drought and semi-drought regions that constrain crop survival. In order to investigate the effect of irrigation intervals on morphological characteristics and yield components of savory plant (Satureja spicigera L.), an experiment was carried out based on randomized complete block design in three levels irrigation interval treatments (7 days (I7), 14 days (I14) and 21 days (I21)) with three replications in Khorasan Razavi Agricultural and Natural Resources Research and Education Center during of 2019. Results showed that with increase in irrigation intervals, all morphological characteristics and yield components were decreased. However there was no significant differences in seed and essence yield, plant canopy area, number of main stems, number of branches and stem diameter due to I7 and I14 treatments. In drought stress (I21), seed width was more affected than seed length. The lowest percentage of survival was observed in I21 treatment which was reduced by 26% and 35% respectively, compared to treatments I14 and I7. By increasing the irrigation interval to 21 days, the highest reduction in savory characteristics occurred, so that the highest and lowest biomass and seed yield were recorded from I7 and I21 treatments, respectively. There was a significant positive correlation between biomass and plant height (r = 0.998*), total plant leaf area (r = 0.770*), number of main stems (r = 0.796*) and number of branches (r = 0.998*). It seems that savory production can be improved in acceptable amount with 14-day irrigation interval.

First report of a ‘Candidatus Phytoplasma aurantifolia’ related strain (16SrII‐C) associated with Convolvulus virgatus witches'‐broom disease in Iran

Convolvulus virgatus (Convolvulaceae) is a perennial shrub which grows mainly in desert and shrubland biomes in Iran, the Arabian Peninsula and Pakistan (Wood et al., 2015). In a 2020 survey for phytoplasma diseases, witches'-broom disease of C. virgatus (WBDCV) was observed in the Roodan area (Hormozgan province, Iran). The main symptoms of WBDCV were flower and stem proliferation, shortened internodes, little leaf, severe witches'-broom, yellowing, reddening, plant sterility and decline (Figs. 1, 2). Total DNA was extracted from leaves and leaf petioles of five symptom-bearing and five symptomless C. virgatus plants using a CTAB-based method. DNA samples were tested for the presence of phytoplasmas by direct-PCR using primer pair P1/P7 (Lee et al., 1998) and nested PCR using primer pairs P1/P7 and R16F2n/R16R2 (Gundersen & Lee, 1996). The expected amplicons of c. 1,800 bp and 1,250 bp were obtained in direct and nested-PCR respectively, from all diseased plants but not symptomless ones. Two R16F2n/R16R2 amplicons were randomly selected and cloned into Escherichia coli DH5α cells using the PCR TA Cloning Kit (SinaClon, Cat. No.:CL5841, Iran) and three plasmid DNAs from recombinant colonies were sequenced. The obtained sequences were identical, and a consensus sequence was deposited in GenBank (Accession No. ON361565). BLASTn analysis of the obtained sequence showed the highest sequence identity (98.7-99.9 %) with phytoplasmas related to ‘Ca. P. aurantifolia’ (16SrII group). Phylogenetic analysis with MEGA11 software using the neighbour-joining method Fig. 3 revealed that the WBDCV phytoplasma clustered within the ‘Ca. P. aurantifolia’ (16SrII) group clade, closest to the strains of subgroup 16SrII-C. In Iran, phytoplasma strains belonging to 16SrII-C subgroup have been reported previously in Bushehr, Fars (adjacent to Hormozgan province) and Yazd provinces in several plant species including Daucus carota, Medicago sativa, Prunus dulcis, Vicia faba (Siampour et al., 2019), Alhagi maurorum and Artemisia sieberi (Esmaeilzadeh-Hosseini & Salehi, 2021); however, this is the first report of a ‘Ca. P. aurantifolia’-related strain in C. virgatus associated with WBDCV in Iran and most probably, in the world. The authors would like to thank the head of the Fars Agricultural and Natural Resources Research and Education Centre, Shiraz, Iran, for support and encouragement.

Effect of Biofertilizer and Drought Stress on Quantitative and Qualitative Traits in Some Winter Rapeseed (Brassica napus L.) Cultivars

To evaluation the effect of plant growth-promoting rhizobacteria under water deficit condition on quantitative and qualitative traits of winter rapeseed cultivars, an experiment was conducted at Agricultural and Natural Resources Research Center located in North Khorasan Province (2015-2017). Plant growthpromoting rhizobacteria (Nitroxin consumption and control) under water deficit condition (after 80, 130, 180 mm evaporation) on quantitative and qualitative traits of winter rapeseed cultivars (Natalie, Okapi, and Neptune) were investigated. Findings indicated that Nitroxin increased soil K, P, Fe, and Cu concentrations and decreased the soil pH and EC. Indeed, the soil N reduction and P increasing trend were related to the maximum biological yield and harvest index (HI) in the second and first years, respectively. Also, an inverse relationship was observed between No. of pods plant-1 (NPP) and No. of seeds pod-1 (NSP) among cultivars. Nitroxin was more affected on NSP and seeds weight than NPP under low and mild drought stress. The highest harvest index was observed in the mild stress in three cultivars, but, the Nitroxin consumption was ineffective. Seed yield and its components except for NPP and HI were increased by the Nitroxin consumption. The HI exhibited the inverse and direct relationship between protein and oil content, respectively. High drought stress compared to low drought stress reduced NPP (54.9%), NSP (1.3%), seed yield (52.2%), biological yield (47.5%), seed oil content (5.5%), seed oil yield (54.9%), and seed protein yield (52.7%). The highest NPP (45.5), seed yield (2740 kg ha-1 ), biological yield (7572 kg ha-1 ), and oil yield (933 kg ha-1 ) were obtained from cv. Natalie. In conclusion, Nitroxin biological fertilizer ameliorates the negative effects of drought stress under mild stressful conditions but it had not any considerable effects on reducing the effects of drought stress under severe stress conditions.

Evaluation of forage maize yield and soil organic matter content under green manure cultivation

To investigate the effect of different green manures from Gramineae and Brassicaceae families on yield, some agronomic traits of forage maize, overgrowth with weeds and soil organic matter, an experiment was conducted based on a randomized complete block design with three replications for three consecutive years (2017-2020) at the Agricultural and Natural Resources Research and Education Centre of Southern Khorasan. Experimental treatments included control (without application of green manure) and application of green manures from the cultivation of barley, triticale, canola, arugula with their optimum and twice optimum densities. The results showed that barley and triticale at twice optimum density with 865.7 and 802.9 g m-2, respectively, had a higher green manure dry mass at the time of returning to the soil. Just before maize cultivation, soil organic matter with an average of 0.73 % was higher in barley green manure at twice optimum density compared to other treatments. Based on the results, the highest maize forage yield with 45.7 and 44.9 t ha-1 were achieved after treatment with barley green manure in twice optimum and optimum density (22.8 and 20.7 percent more than control treatment) and after that triticale in both densities, and canola and arugula at twice optimum density had the highest yield.

Diallel Analysis of Grain Yield and Some Important Agronomic Traits in Bread Wheat

Horticulture Crops Research Department, Golestan Agricultural and Natural Resources Research and Education Center, AREEO, Gorgan, Iran.

First report of a ‘Candidatus Phytoplasma solani’‐related strain (16SrXII‐A) associated with Althaea officinalis yellows disease in Iran

Althaea officinalis (marsh mallow, Malvaceae) is a medicinal plant, the roots, leaves and flowers of which are usually used in traditional medicines in many countries, including Iran (Kianitalaei et al., 2019). During a survey in April 2022, a phytoplasma-type disease, tentatively named A. officinalis yellows (AOY), was observed in patches of A. officinalis plants naturally growing in Golestan, near Shiraz (Fars province, Iran). In a 2-ha surveyed area, the disease incidence was up to 5%. The characteristic symptoms were shoot proliferation from stems, little and deformed leaves, shortened internodes, yellowing, witches’ broom, stunting and plant sterility (Fig. 1 & 2). Total DNA was extracted from five diseased and five asymptomatic A. officinalis plants using a CTAB procedure (Zhang et al., 1998). To examine the presence of phytoplasma, extracted DNA samples were subjected to direct PCR using P1/P7 (Lee et al., 1998) and nested PCR using primer pairs P1/P7 and R16F2n/R16R2 (Gundersen and Lee, 1996). The expected amplicons of c. 1,800 and 1,250 bp (respectively) were obtained only in diseased plants. All five R16F2n/R16R2 amplicons were cloned into Escherichia coli DH5α cells using the InsT/A clone™ PCR product cloning kit (Sinnaclone, Iran) and three plasmids from recombinant colonies were sequenced. The obtained sequences were identical, and a consensus sequence was deposited in GenBank (Accession No. OP572231). A BLASTn search showed that the phytoplasma associated with AOY disease shared the highest sequence identity (100%) to those of Convolvulus arvensis witches’ broom phytoplasma strains, members of ‘Candidatus Phytoplasma solani’ (Salehi et al., 2019), which were detected in Iran in Fars, Lorestan and Yazd provinces in 2019. Phylogenetic analysis using the neighbour-joining method (MEGA7 program) showed that the phytoplasma strain associated with AOY disease clustered within the 16SrXII phytoplasma group closest to 16SrXII-A (‘Ca. P. solani’) subgroup (Fig. 3). The percentage sequence similarity of AOY phytoplasma to the reference strain for the species (AF248959) was 99.28%. In Iran, ‘Ca. P. solani’ (16SrXII-A) phytoplasma strains have been previously reported in several plants such as grapevine, hemp, alfalfa, tomato and bindweed (Siampour et al., 2019); however, to our knowledge this is the first report of ‘Ca. P. solani’ (16SrXII-A) associated with A. officinalis in Iran and probably in the world. The authors would like to thank the head of the Fars Agricultural and Natural Resources Research and Education Centre, Shiraz, Iran, for support and encouragement.

Evaluation of Photosynthetic Roles of Different Canopy Strata and Capitulum on Seed Yield and its Components of Spring Safflower (Carthamus tinctorius L.)

The main source of seed filling results from the photosynthesis of the green tissue closest to the seed sinks in the capitula. To evaluate the role of different leaf strata and capitula in seed yield and its components of Safflower genotypes, a field study was performed as a factorial experiment based on RCBD in 3 replicates in East Azarbaijan Agricultural and Natural Resources Research and Education Center in 2008. The used factors in this experiment were: two Safflower genotypes including (Mahalli Esfahan and Goldasht) and defoliation in five levels: defoliation of plants in lower 1/3, middle 1/3, upper 1/3 of the stem, capitulum covered with aluminum paper and control (without defoliation). The results showed that defoliation did not affect plant height and number of pods. But, there was a highly significant difference between strata in terms of number of seeds per pod, number of seeds per plant, 1000 seeds weight, oil percentage and oil yield. The interaction of genotype×strata treatments in seeds yield and harvest index was significant. Among the defoliation treatment levels in both genotypes, the highest decrease in the seed yield compared to the control were observed in the upper 1/3 defoliation levels, whereas the lowest decrease was observed in the lower 1/3 defoliation level. The rate of seed yield reduction in Mahalli Esfahan was higher than Goldasht. The change in Goldasht seed yield was mostly due to changes in the number of seeds per plant and the number of seeds in the head. In addition, net photosynthesis, strata leaf area, and photosynthesis contribution of the upper strata compared to the lower ones were higher, and removal of the upper strata had the highest effect on seed yield through the reduction in the total photosynthesis of the whole plant. Also, covering the capitulum caused a significant decrease in the seed yield. So, head photosynthesis has a major contribution to Safflower seed yield.

Evaluation of growth, yield, oil content, irrigation water use efficiency of sunflower (Helianthus annuus L.) at different levels of plant density and nitrogen content

Iran has been facing shortage of edible oil and a rapid growing population, and the country has to supplement the needs by importing. To investigate the effect of planting densities and different amounts of some traits of sunflower, an experiment was conducted as a split plot in the form of randomized complete blocks design with three replicates in the research farm of the Agricultural and Natural Resources Research and Education Centre of Semnan province (Shahrood). Plant density in four levels (4, 6, 8 and 10 plant.m−2) as a main plot and the amount of nitrogen levels (0.50, 100, 150 and 200 kg N ha−1) as sub-plot were considered. Leaf greenness index, plant height, 100-seed weight, seed nitrogen content and seed oil content were significantly affected by the simple effect of planting density and decreased with increasing plan density. Also, the nitrogen levels significantly affected the studied traits, so that by increasing the amount of nitrogen application, from control to 200 kg N ha−1, the leaf greenness index increased by 15.3%. At a density of four plant.m−2 and an increase in nitrogen levels, water use efficiency increased along with an increase height and leaf area index, but higher levels of plant density led to smaller plant yield, less plant biomass and lower water efficiency. The highest nitrogen use efficiency was obtained at a density of 8 plant.m−2 and no application of nitrogen fertilizer. Finally, maximum seed yield (4016 kg.ha−1) and oil yield (1827 kg.ha−1) were obtained by applying 150 kg N ha−1 and density of 8 plants.m−2.

Effect of the Application of Foliar Jasmonic Acid and Drought Stress on Grain Yield and Some Physiological and Biochemical Characteristics of Chenopodium quinoa Cultivars

Water shortage is a critical problem touching plant growth and yield in arid and semi-arid areas such as Iran. Plant hormones such as jasmonic acid (JA) play a crucial role in altering plant morphology in response to stress. To investigate the effect of JA and drought stress on grain yield and some physiological and biochemical characteristics of quinoa cultivars, a split-plot factorial experiment based on randomized complete block design with three replications was conducted at Kerman Agricultural and Natural Resources Research and Education Center over two crop years (2018-2019). In this experiment, drought stress as the main factor in two levels including non-stress and stress based on 60% and 90% soil available moisture depletion and JA foliar application (0, 1 and 2 mg L-1) and cultivars (Giza1, Titicaca, Q29) respectively, as factorial were sub factor. The maximum grain yield (3775 kg ha-1) was obtained in Giza1 cultivar under non-stress condition and 1 mg L-1 JA foliar application. The greatest grain protein and total chlorophyll content were obtained in Titicaca cultivar under non-stress and 1 mg L-1 JA foliar application by 18.17% and 1.83 mg g-1 fresh leaf weight, respectively. In the opposite trend, the maximum amount of malondialdehyde was observed under drought stress and non-use of JA. In general, given the results of this study, it can be stated that JA caused an increase in grain yield in quinoa cultivars by reducing the harmful effects of drought stress and improving plant growth.

Yield and morpho-physiological performance of quinoa (Chenopodium quinoa) genotypes as affected by phosphorus and zinc

Meeting nutritional needs and removing restrictions of nutrient uptake ensures quinoa production. This research has been conducted over a two year (2018–2020) in Khuzestan Agriculture and Natural Resources Research Center to appraisal the role of P and Zn elements on changing quinoa genotypes performance by modifying photosynthetic processes and nutrients uptake. This experiment was run as factorial based on a randomized complete block design with three factors and three replicates. In this study, four levels of P2O5 fertilizer (0, 50, 100, 150 kg ha−1), three rates of ZnSO4 (0, 4 and 8 kg ha−1), and three genotypes of quinoa (Giza 1, Q26, Titicaca) were examined. Regarding results, the desirable performance of Giza 1 and Titicaca genotypes was observed in 100 kg ha−1of P2O5 fertilizer and 4 kg ha−1 ZnSO4 treatment. An eight kg ha−1 of ZnSO4 had a negative effect on the quinoa physiological indices. The number of grains per plant was identified as the essential feature, with 94.75% justification of grain yield changes. Nutrient’s analysis exhibited the highest grain quality in top levels of P2O5 and ZnSO4 application, which differed with control mode. Pearson correlation results were implied that grain yield correlated positively and significantly (p ≤ 0.01) with chlorophyll index (CI), number of panicles per plant (NPP), number of grains per plant (NGP), and 1000-grain weight. Upmost photosynthetic power and nutrients efficiency were allocated to Q26 genotype at 150 kg ha−1 level of P2O5 accompanied by 4 kg ha−1 ZnSO4 foliar application, which led to higher grain production.

The Effect of Foliar Application of Magnetic Water and Nano-Fertilizers on Phytochemical and Yield Characteristics of Fennel

Environmental factors, especially nutrients, can influence the production of medicinal plants. Thus, the present study assessed the response of some morphological and physiological characteristics of fennel ecotypes to the foliar application (magnetic water, organic and chemical fertilizers). The study was a factorial experiment based on the randomized complete block design, with three replications and 25 treatments at the research farm of the Agricultural and Natural Resources Research and Education Center of West Azerbaijan province, Iran, in the spring and summer of two consecutive years, 2014–2015 and 2015–2016. The first factor was assigned to fennel landraces (Gaziantep, Hamedan, Urmia, Yazd, and Shiraz) and the second factor to the foliar application (nitrogen nano-fertilizer, magnetic water, urea, chicken manure, and the control). Results showed that interaction of fertilizer treatment and landrace increased fresh and dry weight, biological yield, and seed yield significantly. In the first year, the highest fresh weight (166 g) and dry weight (35.5 g) were observed in the Gaziantep landrace fertilized with chicken manure. The highest anethole and fenchone contents (81.75% and 7.92%, respectively) were observed in the landraces treated with chicken manure. Based on the percentages, the Urmia landrace had the highest anethole percentage (83.2%), and the Shiraz landrace had the lowest one (77.5%). The highest fenchone contents (9.61%) and the lowest (2.18%) were observed in the Yazd and Urmia landraces. Due to the positive effect of application of chicken manure on improving the studied traits of fennel, it is recommended to include chicken manure inputs to enhance the efficiency of crops, reduce environmental pollution, and move toward sustainable agriculture.

بررسی اثر سطوح مختلف نیتروژن و تراکم بر رشد و عملکرد Datura stramonium L.

Datura stramonium L. is one of the important medicinal plants in the pharmaceutical industry due to its alkaloid compounds. To investigate the effects of urea fertilizer at three levels (60, 120, and 180 kg.ha-1) and planting density at three levels (6, 10, and 14 plants.m-2) on the yield and yield components of this plant species, a factorial experiment was conducted in a randomized complete block design in the research farm of Isfahan Agricultural and Natural Resources Research and Education Center, Iran in 2018 and 2019 crop years. The main effects of density and urea on the traits including height, number of lateral branches, and 1000-seed weight and the interaction of different urea and density levels on the traits including seed yield, biological yield, number of capsules per plant, number of seeds per plant, and number of seeds per capsule were significant in both years. The highest seed yield (1282.37 and 1212.53 kg.ha-1, respectively in 2018 and 2019 years) was obtained in the urea fertilizer 180 kg.ha-1 and 6 plants.m-2 treatment. The causal analysis results showed that the highest direct positive effect at the different levels of density and urea was related to the number of capsules per plant. The results of this experiment showed that the application of 180 kg.ha-1 of urea and 6 plants.m-2 could play an important role in increasing the seed yield of medicinal plant D. stramonium.

بررسی تأثیر باکتری تیوباسیلوس، کود گوگردی و فسفری بر جمعیت باکتری‌های حل‌کننده فسفات در خاک

Introduction: According to WHO and FAO studies, the diseases caused by contaminated foods are of the most widespread threats to human health in developing and developed countries. Therefore, in recent years, researchers have been trying to use soil microorganisms to solve this problem and maintain the health of plants and the environment. Phosphorus after nitrogen, is a major macronutrient in plants which controls the growth, seeding and fruit production and involves in basic biological functions such as cell division, nucleic acids synthesis, photosynthesis and respiration and energy transfer. However, high amount of soluble inorganic phosphate is annually applied to the soil as chemical fertilizer but a large portion of it is immobilized rapidly after application due to phosphate fixation by aluminum, calcium, iron, magnesium and soil colloids and becomes unavailable to plants. The use of biological agents especially phosphate solubilizing microorganisms, can play an important role in supplying plant nutrients and improves crop health and productivity without causing any harm in agricultural and natural ecosystems. Bacteria and fungi are the two important groups of phosphate solubilizing microorganisms. Phosphate solubilizing bacteria in soil include Rhizobium, Bacillus, Pseudomonas, Agrobacterium, Achromobacter, Enterobacter and Burkholderia, and the most important ones i.e., Bacillus sp. and Pseudomonas flourescens. Material and Methods: In order to evaluate the effect of Thiobacillus, sulfur and phosphorus applicationon population of phosphate solubilizing bacteria in soil, a field experiment was conducted at Zarghan Agricultural and Natural Resources Research Center of Iran in a factorial, based on complete randomized block design with 3 replications. Treatments consisted of three levels of sulfur fertilizer with biofertilizer containing Thiobacillus bacteria (without sulfur and biofertilizer containing Thiobacillus (S0), application of 500 kg S + 10 kg biofertilizer containing Thiobacillus (S1), 1000 kg S + 20 kg biofertilizer containing Thiobacillus (S2) and 2000 kg S + 40 kg biofertilizer containing Thiobacillus (S3) per hectare), three levels of triple super phosphate (without phosphorus (P0), 100% (P1) and 65% (P2) percent phosphorus recommended based on the soil test) in two corn planted and not planted states. After harvesting, 72 soil samples were collected from each plot and transferred to the biology laboratory of soil and water research institute of Karaj. Soil samples were stored in sterile conditions at 4◦C. In order to isolate phosphate solubilizing bacteria, 10 gram of soil from each sample was suspended in 90 ml of sterilized water to make 1:10 dilution. Then, series of dilution were made (101 – 107) and 0.1 ml of suspensions of the diluted soil sample were transferred to petri dishes containing pikovskaya medium and incubated at 28- 30˚C. To identify PSP from halos surrounding characterized colonies was used and counting was performed 1-14 days after cultivation. The colonies were isolated on the basis morphological characteristics such as shape, color and size and then purified by linear culture. Finally, 60 strains were purified that were used to compare phosphate solubilizing capability. Results and Discussion: The results of this study showed that the main and interaction effects of sulfur fertilizer and biofertilizer treatments of Thiobacillus, phosphorus and plants on the population of phosphate-solubilizing bacteria (cells per gram of dry soil) in Pikovskaya medium were significant at 0.01 level probability. The highest population of bacteria was obtained at the lowest level (S1). Increasing the level of sulfur fertilizer and Thiobacillus biofertilizer decreased the population of phosphate-solubilizing bacteria and the highest level of sulfur and Thiobacillus biofertilizer led to the lowest bacterial population. Also, the study of phosphorus application on the bacterial population showed that phosphorus fertilizer at both levels significantly increased the bacterial population compared to the control (no application phosphorus). The best fertilizer treatment for phosphorus application was P1 which had the greatest effect on bacterial population compared to P2 treatment in Pikovskaya environment. In this experiment, the population of bacteria in corn planted conditions was higher than in non-planted conditions and this population increase was observed in almost all different levels of sulfur and phosphorus fertilizers. The highest bacterial population was observed in combined treatment of S1P2 under corn planted conditions. The results of microscopic, physiological and biochemical tests of the strains showed that all 60 bacterial strains were capable to form clear zone in Pikovskaya medium. Among them, 15 strains (7, 3, 2 and 3 strains belonging to Bacillus megaterium, Bacillus subtilis, Bacillus cereus and Pseudomonas fluorescent, respectively) had higher phosphate solubility than the others.

تولید گیاهان خودریشه گلابی رقم ʼنطنزʽ (Pyrus communis L. cv. Natanz) در شرایط درون‌شیشه‌ای

Introduction Pyrus communis L. cv. Natanz is a popular pear cultivar in Iran because of its customer-friendly attribute due to its excellent characteristics. Pear own-rooted plants has better traits such as high vigorous in growth, low levels on tree losses and damaging by insects (Spornberger et al., 2008; Stanica et al., 2000) rather than cut-rooted and grafted plants. Meristem culture widely used for micropropagation (Erij and Fortes, 2002; Postman and Sugar, 2002), in vitro germplasm preservation (Reed, 1990; Niino and Sakai, 1992; Scottez et al., 1992; Bell and Reed, 2002; Sedlak el al., 2004) and virus eradication purposes in pear (Postman, 1994; Zilka et al., 2002; Dong et al. 2002; Hong et al., 2004; Wang et al., 2006; Postman and Hadidi, 1995; Tan et al. 2010). As pear is belonged to difficult-to-root fruit tree cultivars perhaps the rooting stage is the most important, yet most difficult phase during the in vitro propagation procedure. In vitro rooting of microcuts was varied by genotypes (cultivars) (Sedlak and Paprstein, 2015), type and concentration of used auxin (A1-Maarri el al., 1994; Sedlak and Paprstein, 2015), the method of root induction and formation (Bhojwani et al., 1984; Saadat et al., 2012; Erturk, 2013; Aygun and Dumanglu, 2015), different additional materials such as PVP, polyamines, PP333 (Marino, 1988; Rugini et al., 1992; Erturk, 2013) and so on. Materials and Methods Vegetative buds were taken from current growth shoots of Pyrus communis cv. Natanz from Pear collection orchard (25.36 E, 58.54 N and altitude 1380 meter) of Agricultural and Natural Resources Research and Education Centre of Semnan Province (Shahrood city). New shoots of active buds after 4 weeks transfer to PMI media (Reed et al., 2013) containing BA (0.5, 1, 1.5 mg l-1) and Fe-EDDHA (0, 100, 150 and 200 mg l-1). Meristems (containing 2 newest leaf primordia) was excited from in vitro shoots and incubation on MS media containing BA (0.5, 1, and 1.5 mg l-1) and GA3 (0.1 and 0.5 mg l-1) plus 0.1 mg l-1 IBA for all treatments. Mersitems were kept in dark for 4 days then were transferred to growth chamber. Different concentrations and combinations of two auxins were used. 1000, 2000, 3000 and 4000 mg l-1 of IBA or NAA and two combination solutions of them (1000 IBA+1000 NAA and 2000 IBA+2000 NAA, mg l-1). Shoots were immersing quick dip in solutions for 5 seconds then transfer to PGRs-free PMI medium and kept them to growth chamber. Data of all experiments were analyzed according by completely randomized design (CRD) with 5 replications. BA (3 levels) and Fe-EDDHA (4 levels) for experiment 1; BA (3 levels) and GA3 (2 levels) for experiment 2 were considered as factorial. SAS (v. 9.1) was used for analysis and means were compared with LSD test at 5% probably level. Results and Discussion Proliferated shoot number was affected by BA (p≤0.01) and Fe-EDDHA (p≤0.05) concentrations and also interaction of them (p≤0.05) while BA (p≤0.01) was caused elongation of proliferated shoots and Fe-EDDHA had no effect. BA (p≤0.05), Fe-EDDHA (p≤0.01) concentrations and BA×Fe-EDDHA (p≤0.01) interaction had significant effect on leaf production. Shoot tip necrosis was shown in shoots grown in all media based on BA concentration with different intensities (p≤0.05). Vegetative growth was counted as a power index of medium that in our experiment was under influence of BA concentrations (p≤0.01), Fe-EDDHA (p≤0.05) and BA×Fe-EDDHA interaction (p≤0.05). Shoots were proliferated (5.50 shoot/explant) and elongated in PMI media (MS ×1.5 CaCl2. 2H2O, KH2PO4 and MgSO4. 7H2O) containing 1.5 mg l-1 BA with no Fe-NaEDDHA while the lower concentrations of both BA and Fe-NaEDDHA caused the higher mature leaf production. PMI media containing 1 mg l-1 BA plus 150 mg l-1 Fe-NaEDDHA is recommended for Natanz shoot proliferation because of the highest vegetative growth and highest quality in proliferated shoots. MS media with 0.5 mg l-1 BA+ 0.5 mg l-1 GA3 (81%) and 1 BA mg l-1 + 0.1 mg l-1 GA3 (63%) had the highest meristem establishment, respectively. The established meristems in media supplement of 0.5 mg l-1 BA + 0.5 mg l-1 GA3+0.1 mg l-1 IBA naturally grown. Different types of auxin and their concentrations had significantly effect on Natanz pear cultivar microshoots rooting (p≤0.05). NAA induced rooting in lower concentrations while IBA had positive effect on rooting with concentration increasing. Microcuts were rooted via quick dip in 1000+1000 mg l-1 (IBA+NAA) solution followed by incubation in PMI medium. The rooted shoots well adapted to environmental condition.

Agro-physiological parameters for improving drought tolerance in rapeseed genotypes to cultivate in saline soils

ABSTRACT- This study was conducted to introduce agro-physiological traits for improving drought tolerant rapeseed winter genotypes for cultivation in saline areas. Eighteen rapeseed genotypes were evaluated under non-stressed and drought-stressed conditions from flowering and seed filling stages to seed maturity for two years (2012-2014) at the saline soils (EC=6.7 dS m-1) in Agricultural and Natural Resources Research and Education Center of East Azarbaijan, Iran. Drought stress significantly decreased pod length, plant height, seed yield, yield components and stomatal conductance and increased canopy temperature.Among the genotypes, significant differences were observed for pod length, the number of seeds in a pod, seed and oil yields, and stomatal conductance. The correlations among the traits were significantly positive. According to the results of genotypes grouping, HW101, L183, L73, and L72 having higher pod length, the number of seeds in a pod, stomatal conductance, seed and oil yields, which were recognized as the promising ones. The results of this study indicated that, the pod length, the number of seeds in a pod and stomatal conductance as simple and easy parameters can be used to select late season drought tolerant rapeseed winter genotypes for cultivation in saline areas. Also, the cluster analysis method was able to discriminate productive genotypes. Water deficit during flowering and seed filling stages, decreased the mean of seed yields by 800 and 584 Kg h-1 during the first year and 1764 and 1154 Kg h-1 during the second year of the experiment, of this study respectively. Thus, it was concluded that the evaluated rapeseed genotypes at the flowering stage were more sensitive to drought compared to the seed filling stage.