Effect of some metal-containing compounds and fertilizers on mycoparasite Trichoderma species mycelia growth response

Response of three biocontrol agents including Trichoderma harzianum T969, Trichoderma hamatum T614 and Trichoderma virens T525 in the presence of 0, 50, 91.2, 166, 302, 550 and 1000 mg/l concentrations of MgSO4.7H2O, ZnSO4.7H2O, CuSO4, FeSO4.7H2O, MnSO4.H2O, CoCl2.6H2O, CaCl2.2H2O and (NH4)2SO4 via poisoned medium method, were studied. Radial growth of the Trichoderma isolates were recorded 48 and 72 h after inoculating. For each experimental set, experimental design used was completely randomized design (CRD) through factorial experiment with 3 factors. Also, inhibition percentage of the fungus mycelia growth due to metal containing compound at the inhibitory effectexhibited compound was calculated. The experiments indicated that Trichoderma species mycelia response to the compound differed noticeably in their sensitivities to the metal containing compounds and fertilizers exposure. ZnSO4.7H2O, CuSO4, FeSO4.7H2O, MnSO4.H2O and CoCl2.6H2O compounds were effective as radial growth inhibitors, though (NH4)2SO4, MgSO4.7H2O and CaCl2.2H2O were found to be non-toxic to the Trichoderma species. Meanwhile, CuSO4 indicated the strongest inhibition towards the in vitro mycelia expansion of the fungi

Wheat crown and root rotting fungi in Moghan area, Northwest of Iran

Wheat root and crown rot (Triticum aestivum L.) is a disease problem in many wheat producing area as well as Moghan wheat growing area, Northwest of Iran. In this study, injured plants of wheat withblighting, stunting, and death of mature plants, also necrotic lesions on seminal crown roots, sub crown internodes and crown, as well as basal stem tissue symptoms were collected from different regions of Moghan wheat growing area. Fungi associated with wheat root and crown rot were isolated and identified based on general colony morphology, the morphology of mycelia, reproductive structure and taxonomic description. Also pathogenicity of 28 selected isolates from various identified specieswas determined on wheat (T. aestivum L. CV. Atila 4; a common grown cultivar of wheat in Moghan area) seedlings. The results indicated that the predominant pathogens implicated in causing common root and crown rot in this study was Bipolaris sorokiniana. In addition to B. sorokiniana, Fusarium culmorum, Fusarium Pseudograminearum and Gaeumannomyces/Phiallophora complex are the most widely distributed species on wheat growing belt in Moghan area. Fusarium solani, Fusariumcrookwellence, Fusarium clamidosporum, Fusarium proliferatum, Fusarium poa, Fusarium udum and Fusarium babinda are wheat root associated species of Fusarium ascertained during our investigation. Pathogenicity test revealed that B. sorokiniana, F. culmorum, F. graminearum, F. crookwellence, F. udum and Gaeumannomyces/Phiallophora complex are active pathogens and others are saprophytes, which are also involved in the destruction of root tissues, without being the cause of injury

Effects of some Iranian Trichoderma isolates on maize seed germination and seedling vigor

Trichoderma species are commonly used as biological control agents against phytopathogenic fungi and some of their isolates are able to improve plant growth. In the current study, we evaluated someIranian Trichoderma isolate cultural filtrates as well as their direct effect on seed germination and seedling vigor of maize (Zea mays L. cultivar B73); they are Trichoderma harzianum T 969, T. harzianum T 447, Trichoderma hamatum T 614, Trichoderma roseum T678, Gliocladium virens G525 and the unknown Trichoderma species isolate (Trichoderma sp. T) obtained from the soil of Moghan Area, Ardabil Province of Iran. The culture filtrates reduced the speed of seed germination, but no influence (p0.05) was recorded at the final rate of the seed germination. When maize seeds were exposed to the Trichoderma spore suspension, all the Trichoderma isolates colonized the seed surface and inhibited the seed germination. The maize seed potted in inoculated soil did not emerge from the soil among all tested Trichoderma isolates, except for non-inoculated soil 30 days after potting. When Trichoderma conidia were added on the surface of soil near the emerged seed, significant (p0.01) decrease of seedling treated separately with T. hamatum T614 isolate was observed on the leaves area, fresh root and shoot weight, compared to the non-inoculated seedling. Whereas T. hamatum T447 and T. harzianum T969 reduced markedly (p0.01), seedling fresh root weight and fresh shoot weight wererespectively increased as compared to the control. Trichoderma isolates had no influence on chlorophyll content in leaves and root length as well as stomata conductivity, except for Trichoderma spp. isolate T that increased stomata conductivity of seedling significantly (p0.01)

Phoma negriana, a new invasive pathogen for Moghan's vineyards in Iran

During disease diagnosing studies in Moghan area, northern west of Iran, symptoms of black rot and necrosis were observed for the first time on Vitis venifera. Incidence was first noticed on leaves and stems. Symptoms occurred as small brown spots on leaves and stems, and developed as blackishbrown necrosis/canker so that the black pycnidia extended at the central parts of them. On the fruit, symptoms appeared as mummification of berries that were visible in the infested vineyards until winter time. The loss due to the disease along with downy mildew was remarkable during the studied years and can lead to substantial yield losses in Moghan climate condition. In order to identify the causal agent, the pathogen was isolated from infected leaves and stems. Also pathogenesity test was carried out by inoculating the causal agent to grapevine cuttings. According to culture, pycnidia and conidia characteristics described by Boerema et al. (2004), the results pointed toward Phoma negriana Thum asthe causative organism

Effect of Trichoderma spp. inoculation on the chemical composition and in vitro digestibility of wheat straw

To evaluate the cultural ability of some Trichoderma isolates on wheat straw and the influence of their exogenous enzyme activities on chemical compositions as well as in vitro digestibility and upgrading of the nutritive value of lignocellulolytic materials, sterilized and non sterilized wheat straw were inoculated with Trichoderma isolates (including Trichoderma harzianum isolate T447, T. hamatum isolate T 614, T. hamatum isolate T625 and T. harzianum isolate T 969). The experimental design usedin this study was complete randomized design (CRD) through factorial experiment with 2 factors (factor A = effects of sterilization, factor B = effects of Trichoderma spp.) in three replicates for each treatment. Effects of the Trichoderma isolates on the substrate neutral detergent fiber (NDF), acid detergent fiber (ADF) and pH as well as in vitro dry matter (DM) digestibility (IVDMD), in vitro organic matter (OM) digestibility (IVOMD) and in vitro digestible OM in DM (IVDOMD) were analyzed. The obtained results showed that sterilization of wheat straw could decrease pH, NDF and ADF (P<0.05) but not IVDMD, IVOMD and IVDOMD. The isolates of T447 and T969 showed higher ability in improving the nutritive value of wheat straw. Comparatively, higher reduction in pH was recorded by T614 inoculatingsterilized wheat straw. The least NDF content were observed in treated non-sterilized wheat straw with T447, also treated sterilized wheat straw with T447 showed maximum reduction in NDF content. Moreover, higher change in IVDMD, IVOMD and IVDOMD were obtained by T447 grown in sterilized wheat straw substrate

Sugarcane mosaic virus: The causal agent of mosaic disease on sorghum (Sorghum bicolor L.) in Tehran province of Iran

During disease diagnosing studies on sorghum fields in Tehran province, Iran through vegetation period in 2005 - 2006, 75 sorghum expressing virus-associated symptoms including mosaic, leafredding and necrosis were collected. The virus was inoculated mechanically to Sweet corn (Zea mays cv. Pars403) and grain sorghum (Sorghum bicolor cv. Kimia). The virus specifically was reacted in Double Antibody Sandwich-Enzyme Linked Immunosorbent Assay (DAS-ELISA) and Dot Immunobinding Assay (DIBA). Also relative molecular mass of virus coat protein was calculated using adensitometer via sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) to determine electrophoretic mobility compared with protein standards. The virus reacted with anti SCMV polyclonal IgG antiserum and was detected with Goat anti-Rabbit IgG alkaline phosphatase conjugate. The total nucleic acids were subjected to reverse transcription-polymerase chain reaction (RT-PCR) using SCMV degenerate and specific primers. Sugarcane mosaic virus (SCMV) was detected in allcollected samples. The capsid protein was evaluated approximately 37 kDa in size. Amplification product (approximately 900 bp) was obtained from the collected and inoculated plants but not from healthy plants. This may confirm the presence of SCMV in the symptom-expressing plants

The effect of sheep-manure vermicompost on quantitative and qualitative properties of cucumber (Cucumis sativus L.) grown in the greenhouse

This experiment aims to evaluate the effects of vermicompost produced from sheep manure on growth, yield and quality of 2 fruit cucumber (Cucumis sativus L.) varieties (cv. ‘Sultan F1’ and cv. ‘Storm F1’)under greenhouse condition. Four vermicompost treatments at the rate of 0 (control), 10, 20 and 30 t ha-1 were incorporated into the top 15 cm of soil. During the experiment, fruits were harvested three timesper week and fruit number and weight were recorded for 3 months. Leaf number, plant height and chlorophyll content were measured at 30, 60 and 90 days after transplanting, while leaf area, stem and leaf dry weight and fruit qualitative properties were evaluated at 90 days after transplanting. The results showed that leaf number, plant height and chlorophyll content increased significantly (P 0.05) compared to control plots for both varieties at 30, 60 and 90 days after transplanting. The plots treatedwith 30 t ha-1 vermicompost showed increase in leaf are, stem and leaf dry weight for both varieties. The application of vermicompost at 30 t ha-1 increased total fruit yield 26% for cv. ‘Sultan F1’ and 25% for cv.‘Storm F1’ compared to the control. The plots treated with vermicompost at 30 t ha-1 enhanced fruit number per plant 26% for cv. ‘Sultan F1’ and 25% for cv. ‘Storm F1’ than plot without vermicompost. Fruit harvested from plants receiving vermicompost had higher total soluble solid (TSS), lower juice acidity and more dry matter than plots without vermicompost. Growth and yield parameters were improved with increasing vermicompost rates up to 20 t ha-1. There are no significant different between plots at 20 and 30 t ha-1 vermicompost in all evaluated parameters

Effect of Trichoderma isolates on tomato seedling growth response and nutrient uptake

Trichoderma species are commonly used as biological control agents against phytopathogenic fungi and some isolates are able to improve plant growth. In this study, the effects of three Trichoderma isolates including Trichoderma harzianum isolate T969, T. harzianum isolate T447 and Trichoderma sp. isolate T in tomato seedling vigor and their nutrient uptake via two inoculants introduction methods (inoculating seed with Trichoderma spore suspension and inoculating nursery soil with Trichoderma fortified wheat) were examined. Seed germination rate was not affected by Trichoderma application, but shoot height, shoot diameter, shoot fresh and dry weight and root fresh and dry weight in tomato seedlings were interestingly (p ≤ 0.05) increased when sown in Trichoderma sp. T and T. harzianum T969 fortified soil and when compared to the control. The soil amended by Trichoderma sp. T and T. harzianum T969 had marked increase in leaf number and leaf area (p ≤ 0.05). Chlorophyll content increased in seedling grown in Trichoderma sp. T amended soil as well as in Trichoderma sp. T and T. harzianum T969 coated seed. A dramatic increase (p ≤ 0.05) in the concentrations of Ca2+, Mg2+, P and K+ were recorded in the seedling shoot and root among T. harzianum T447 soil amended treatment when compared to the control, except for Na+ level in soil amendment with T. harzianum T969 and seedcoating with strain Trichoderma sp. T, which significantly reduced the Na+ concentration.Key words: Growth response, nutrient uptake, tomato seedling, Trichoderma harzianum

Comparative d2/d3 LSU–rDNA sequence study of some Iranian Pratylenchus loosi populations

The D2/D3 LSU rDNA expansion segment of 13 isolates attaching tea shrubs roots in tea gardens that verified by morphological and morphometrical studies as Pratylenchus loosi Loof, 1960 from Guilanprovince, North of Iran, were amplified and sequenced. Amplification of the D2/D3 LSU rDNA expansion segments yielded one fragment at over all sequenced isolates as 787 bp in size. The DNA sequenceswere aligned using Clustral X1.81 together and with three sequences of similar region of P. loosi isolates available in Genbank database (Isolate T from Serilanka and Isolates N1 and N2 from Florida, USA). Also the genetic distance between sequences data were calculated through four methods as following; Uncorrected distance (UC), Jukes-Cantor (JC) Kimura distance (K) and Jin-Neigamma distance (JNG).For generating phyllogenetic trees both Neighbor-joining (NJ) and Unweighted Pair Group Method with Arithmetic Mean (UPGMA) were used. The results indicated that very short genetic distance exist among the Iranian isolates and between the Iranian isolates and isolate T from Serilanka whereas the Iranian isolates and isolate T were genetically distinct from isolates N1 and N2. The phyllogenetic analyses revealed relationship not only among Iranian isolates but also between Iranian isolates and isolate T