Effects of IBA, bacterial and mycorrhizal treatments on the rooting of Crataegus pseudohetrophylla Pojark. cuttings

This study was carried out to determine appropriate methods for rooting and seedling production of Crataegus pseudohetrophylla Pojark. from hardwood cuttings by IBA, bacterial and mycorrhizal treatments and two different sources of sprout and seedling. For this purpose, cuttings were sown in two separate experiments in a Complete Randomized Design (CRD) with 11 treatments and 3 replications of 10 cuttings in greenhouse benches. Treatments contained dipping the basal end of cuttings in H2O2 (3.5% w/v) followed by the application of IBA at concentrations (0, 1, 2, 3, 5, 8, and 10 g l-1) or dipping in 4 g l-1 IBA and then application of bacterial suspension of Agrobacterium rhizogenes A13, Pseudomonas fluorescens 169, Bacillus subtilis FzB24, and mycorrhizal inoculums of Glomus intraradices. In the first experiment, cuttings from sprout source were sown in greenhouse benches. The seedlings were transplanted to the open field condition after three months, and were assessed for rooting characteristics after a season of growth. In the second experiment, cuttings were prepared from seedlings produced from the first experiment, and the experiment was conducted in greenhouse and open field conditions and with similar treatments to those applied in the first experiments. Results showed that in the first experiment the highest rooting percentage was obtained in the combination of H2O2 with 3 g l-1IBA, and the highest root area, specific leaf area, total seedling dry weight, height, and total chlorophyll contents were obtained when a combination of IBA with bacterial suspension of A. rhizogenes was applied. In the second experiment, the highest rooting percentage was observed for the combination of H2O2 with 3 and 5g l-1IBA, as well as for the combination of IBA with bacterial suspension of A. rhizogenes

Effect of Growth Promoting Rhizobacteria on growth and nutrient elements of common hazelnut (Corylus avellana L.) seedlings in Ardabil Fandoqlou nursery

The aim of present research was to investigate the effects of Growth Promoting Rhizobacteria on growth (height, collar diameter, dry weight of root and shoot, total dry biomass and quality index of seedling) and nutrient absorption (N, P, K, Fe and Zn) in leaf of common hazelnut (Corylus avellana L.) For this purpose, effects of three bacteria including Pseudomonas putida, Bacillus subtilis and Enterobacter cloacae, alone and together, for 7 months on filbert seedling in pots containing of autoclaved soil under nursery conditions were evaluated. The results showed that the greatest height (26.88 cm), collar diameter (7.17 mm), leaf area index (23.87 cm2/g) and N concentration (2.81%) were observed for seedlings inoculated with all bacterial. The biggest root dry weight, root volume, seedling quality index and P concentration were observed in seedlings inoculated with P. putida (alone). The highest Fe and Zn were obtained in seedlings inoculated with B. subtilis and P. putida, respectively. Generally, according to beneficial effects of Growth Promoting Rhizobacteria on absorption of nutrient elements and morphologic growth, P. putida, B. subtilis and E. cloacae are recommended for seedling inoculation, respectively. In fact, inoculation of root with Growth Promoting Rhizobacteria (root engineering) can be an appropriate approach to produce healthy and strong seedlings in nursery and increasing success of plantation in disturbed and degraded habitats

Non-linear height-diameter models for oriental beech (Fagus orientalis Lipsky) in the Hyrcanian forests, Iran

The relationship between tree height and diameter is an important element in growth and yield models, in carbon budget and timber volume models, and in the description of stand dynamics. Six non-linear growth functions (i.e. Chapman-Richards, Schnute, Lundqvist/Korf, Weibull, Modified Logistic and Exponential) were fitted to tree height-diameter data of oriental beech in the Hyrcanian mixed hardwood forests of Iran. The predictive performance of these models was in the first place assessed by means of different model evaluation criteria such as adjusted R squared (adj R2), root mean square error (RMSE), Akaike information criterion (AIC), mean difference (MD), mean absolute difference (MAD) and mean square (MS) error criteria. Although each of the six models accounted for approximately 75% of total variation in height, a large difference in asymptotic estimates was observed. Apart from this, the predictive performance of the models was also evaluated by means of cross-validation and by splitting the data into 5-cm diameter classes. Plotting the MD in relation to these diameter at breast height (DBH) classes showed for all growth functions, except for the Modified Logistic function, similar mean prediction errors for small- and medium-sized trees. Large-sized trees, however, showed a higher mean prediction error. The Modified Logistic function showed the worst performance due to a large model bias. The Exponential and Lundqvist/Korf models were discarded due to their showing biologically illogical behavior and unreasonable estimates for the asymptotic coefficient, respectively. Considering all the above-mentioned criteria, the Chapman-Richards, Weibull, and Schnute functions provided the most satisfactory height predictions. However, we would recommend the Chapman-Richards function for further analysis because of its higher predictive performance.status: publishe

Effect of soil texture on growth and yield of eastern cottonwood (Populus deltoides Bartr. ex Marsh. 77/51) in Noor alluvial plain

In recent decades, poplar cultivation as wood farming has been developed up to 50 thousand hectares using the fast growing eastern cottonwood (Populus‌‌ deltoides‌‌ Bartr. ex Marsh. 77/51) has become a common practice in north of Iran. The current study aimed to select appropriate sites for increasing growth and yield of this poplar clone. For this purpose, three different 20 years-old plantations on three different media naming: loam, silt-loam and silt-clay-loam soils of Noor alluvial plain in north of Iran were selected. The measurements were carried out based on 400 m2 plots with four replications. Quantitative and qualitative analysis showed significant differences among poplar trees grown on different soil textures beds. The poplar trees grown on loamy soils displayed the highest annual height increment of 1.27 m and volume of averaged tree of 0.956 m3. Values for average diameter, basal area and volume ha-1 were also highest in trees grown on loamy soil with total 29.1 cm, 32.59 m2 ha-1 and 443 m3 ha-1, respectively. The mean height of the trees in the silt- loam soil (24.47 mm) was significantly greater than that of the silt- clay- loam. Values for diameter increment and basal area of trees were higher in the silt- clay- loam than in silt- loam soil. In order to get an initial understanding of the habitat condition, clone selection and improvement operation, analyzing of soil is essential prior to planting of trees. In this case we can ensure and guarantee the plantation and the investment would be less risky

B A S E Non-linear height-diameter models for oriental beech (Fagus orientalis Lipsky) in the Hyrcanian forests, Iran

The relationship between tree height and diameter is an important element in growth and yield models, in carbon budget and timber volume models, and in the description of stand dynamics. Six non-linear growth functions (i.e. Chapman-Richards, Schnute, Lundqvist/Korf, Weibull, Modified Logistic and Exponential) were fitted to tree height-diameter data of oriental beech in the Hyrcanian mixed hardwood forests of Iran. The predictive performance of these models was in the first place assessed by means of different model evaluation criteria such as adjusted R squared (adj R 2 ), root mean square error (RMSE), Akaike information criterion (AIC), mean difference (MD), mean absolute difference (MAD) and mean square (MS) error criteria. Although each of the six models accounted for approximately 75% of total variation in height, a large difference in asymptotic estimates was observed. Apart from this, the predictive performance of the models was also evaluated by means of cross-validation and by splitting the data into 5-cm diameter classes. Plotting the MD in relation to these diameter at breast height (DBH) classes showed for all growth functions, except for the Modified Logistic function, similar mean prediction errors for small-and medium-sized trees. Large-sized trees, however, showed a higher mean prediction error. The Modified Logistic function showed the worst performance due to a large model bias. The Exponential and Lundqvist/Korf models were discarded due to their showing biologically illogical behavior and unreasonable estimates for the asymptotic coefficient, respectively. Considering all the above-mentioned criteria, the Chapman-Richards, Weibull, and Schnute functions provided the most satisfactory height predictions. However, we would recommend the Chapman-Richards function for further analysis because of its higher predictive performance. Keywords. Forest trees, Fagus orientalis, simulation models, growth, Iran. Modèles non linéaires de diamètre de hauteur pour le hêtre oriental (Fagus orientalis Lipsky) dans les forêts Hyrcaniennes en Iran. La relation entre la hauteur des arbres et le diamètre est un élément important pour les modèles de croissance, de rendement, du budget de carbone et de volume du bois, et pour la description de la dynamique des peuplements. Six fonctions de croissance non linéaires (Chapman-Richards, Schnute, Lundqvist/Korf, Weibull, fonctions logistiques et exponentielles modifiées) ont été ajustées aux données de diamètre de hauteur des arbres de hêtre oriental dans les forêts mélangées hyrcaniennes d'Iran. La performance prévue des modèles a été évaluée à l'aide du R² ajusté (adj R²), de l'erreur quadratique moyenne (RMSE), du critère d'information d'Akaike (AIC), de la différence moyenne (MD), de la différence absolue moyenne (MAD) et de l'erreur quadratique moyenne (MS). Les résultats ont montré que chacun de ces six modèles représente environ 75 % de la variation totale de hauteur, mais produit différentes estimations asymptotiques. La performance prévue a également été évaluée à l'aide des validations croisées et par séparation des données en classes de 5 cm de diamètre à hauteur de poitrine (DBH) afin de calculer le MD pour chaque classe. Les visualisations de MD pour toutes les classes DBH ont montré que les six fonctions de croissance, sauf la logistique modifiée, produisent des erreurs de prédiction moyennes similaires pour les arbres de tailles petites et moyennes. Cependant, pour les arbres de grande taille, l'erreur de prédiction moyenne est plus élevée. La fonction de logistique modifiée est la moins performante, en raison d'un large biais. Les modèles exponentiels et de Lundqvist/Korf ont été rejetés en raison, respectivement, de leur comportement biologique illogique et des estimations déraisonnables pour les coefficients asymptotiques. En envisageant tous les critères mentionnés ci-dessus, les fonctions Chapman-Richards, Weibull et Schnute fournissent les prédictions de hauteur les plus satisfaisantes, mais la fonction de Chapman-Richards pourrait être recommandée pour une analyse plus approfondie en raison de sa meilleure performance