Water requirement and water use efficiency in Eucalyptus flocktoniae (Maiden) Maiden and E. leucoxylon F. Muell.

The response of plants to water available for strategy codification of water resources and irrigation is very important. In this study, evapotranspiration, crop coefficient, yield and water use efficiency in two species of Eucalyptus (Eucalyptus flocktoniae (Maiden) Maiden, E. leucoxylon F. Muell.) through lysimeter experiments were determinated under different soil moisture levels (100%, 70% and 40% of field capacity). The research was designed as a factorial experiment on a completely randomized design with three replications in Yazd climatic conditions. The results showed that with increasing soil moisture in both species, evapotranspiration increased, so that there were significant differences between the different levels of soil moisture treatments (p < 0.001). E. flocktoniae and E. leucoxylon had water requirement in 100% of field capacity treatment, 1185 mm and 1617 mm with 0.65 and 0.88 crop coefficients, respectively. Dry matter produced in all parts and the water use efficiency (WUE) of E. leucoxylon were significantly higher than that of E. flocktoniae, Water use efficiency measured in E. flocktoniae and E. leucoxylon, were 1.22 g/lit and 1.41 g/lit, respectively. Although the growth rate of E. leucoxylon is faster than E. flocktoniae , therefore its water requirement is higher , but considering an appropriate mechanisms for drought adaptation, it could be introduced for afforestation and wood production in arid and semi-arid regions

Response of the root of Eucalyptus camaldulensis Dehnh. to drought stress

Root distribution of three-year-aged Eucalypt (Eucalyptus camaldulensis Dehnh.) seedlings was determined under different soil moisture regimes in Yazd, Shahid Sadoge Desert Research Station. The seedlings were grown in lysimeters which subjected to three soil moisture regimes including; 100% (well watered), 70% (mediumdrought stress) and 40% (highdrought stress) of field capacity (FC). Soil moisture was restored by adding the required volume of water in the basis of time domain reflectometry (TDR) reading taken from tubes installed in each lysimeters. The roots were harvested at 0-30, 30-60, 60-90 and 90-120 cm depth of the soil at the end of the experiment. Results showed that root dry weight and length decreased significantly when soil water content reduced (

Tolerance of few Eucalypt species to salinity in Vitro

Most of the salinity problems causes by NaCl distribution in dry lands, beaches and water resources. This research was carried out to estimate the salinity resistance of four Eucalyptus species: Eucalypus camaldulensis, E. microtheca, E. kingsmillii and E. tetragona. Five NaCl level (0, 50, 100, 150 and 200 mM) treatments were used in three replication in a factorial experiment design based on completely randomized plots. Sampling were made from stamen leaves of different treatments and pigments (total chlorophyll, chlorophyll a and b, carotene, soluble sugar and prolin) and growth parameters (biomass, leaf  area, relative water content, water saturation deficient (WSD), specific leaf area (SLA) and leaf water content per unit leaf area (LWCA)) and other characters including withering, falling and drying leaves were measured. Increased of salt stress leds to increased prolin, soluble sugar and withering, falling, drying leaves and decreased pigments and growth parameters in four species. Between the studied species, E.microtheca showed the most tolerant salt stress, although for prolin, soluble sugar, pigments, SLA, LWCA, WSD had the highest quantity and for the withering, falling and drying leaves had the lowest quantity

Impact of different Eucalypt species on forest soil properties in Guilan province

The aim of this study was to investigate the positive or negative effects of eucalypt plantation on different soil properties. For this reason, an eucalypt trial consisting of six species: E. camaldulensis, E. macarthurii, E. maidenii, E. rubida, E. saligna, E. viminalis which were planted in 1983 in Sheikh-Neshin state of Shafarud Company in Guilan province under experimental design of Randomized Complete Blocks with four replications at 2×2 m spacing and total number of 100 seedlings at each plot, was used for this research. Soil samples were taken from each plot, including four control ones by auger up to 60 cm. depth (totally 28 samples). Soil morphology was studied by digging three soil profiles at the eucalypt site and two adjacent parcels, including poplar plantation and the oak forest. Soil samples were taken from four soil horizons of each profile (totally 12 samples). Results showed that the species have differed significantly in respect to only few soil properties, including silt percentage, litter dry weight, bulk density, penetration resistance, pH and phosphorous amount. The soil profiles at the eucalypt site and the two adjacent sites of poplar plantation and oak forest consisted of four horizons, including A, AC, B and C. Root development at eucalypt, poplar and oak sites limited to 100, 85 and 150 cm soil depth, respectively. Overall, eucalypt plantation was able to improve soil structure and porosity, particularly at topsoil. Although there was intensive livestock traffic in the eucalypt site, but soil compaction was significantly less than the control plots and there was not significant difference between the eucalypt species in response to penetration resistance. Eucalypt plantation after 22 years reduced soil pH, but it was less than one unit

Investigation on potential of few eucalypt species for absorbing pollutants and reserv-ing them in their leaves

Trees as alive components of an ecosystem are able to convert some of the environment contaminants to unharmful substances and store some of them in their tissues and reduce their density and intensity in the air and soil by breath, root absorption and photosynthesis and other biotic functions. Trees function in such condition is completely related to environmental and habitat circumstances and their physiological potential. At beginning, five research sites at Khuzestan and Bushehr provinces were selected among the contaminated area by the Gulf War. At each site, soil sampling was made from three levels of depth (0-20, 20-40 and 40-60 cm). Soil physical and chemical characteristics test was made to measure nine metal elements and 12 other soil properties. The eucalypt species consisted of: E. camaldulensis, E. camaldulensis 9616, E. microtheca and E. sargentii which were planted under the Randomized Complete Blocks statistical design with three replicates. Before sampling the trees for determining the contaminant elements. Three individual trees were selected at each plot per one replicate to make sampling for leaf (four specimens per tree at four mean geographical directions). The data were analyzed under the variance analysis and Duncan test programs, using Excel and SAS computer soft wares. Overall, amount of the contaminants in different sites and at three levels of depth was not significantly different. The best eucalypt species and the best sites for absorbing the contaminants in their leaves are respectively as follows: 1-       E. camaldulensis, E. microtheca, E. sargentii and E. camaldulensis 9616 2-       Dezful, Isvand, Shooshtar, Karkheh and Kaki. The species which made the best performance in relation to their site interaction are respectively as follows: 1-         E. microtheca firstly at Karkheh and shooshtar sites and secondly at Dezful and Isvand sites. 2-                        E. camaldulensis 9616 3-                        E. camaldulensis and E. sargentii

Preliminary growth of individuals Populus euphratica, gametoclonal and hybrids (P. euphratica with P. alba) at the first 5-years in Dezful botanical garden

Poplar trees are appropriate species for plantation and forest rehabilitation because of fast growing and high wood yield, as well as adaptability to unfavorable climate. Salinization of soil and high temperature are the inhibitory factors in Khuzestan province. Populus euphratica is a tree species that tolerates soil salinity and high temperature. Acclimatization of cut seedling of three Populus genotypes including P. euphratica, gametoclonal of P. euphratica and hybrids of P. euphratica with P. alba were studied in Dezful botanical garden of Khuzestan province in southwest of Iran. Heterosis effect was observed for hybrid trees and they had higher yield than the Khuzestan's endemic P. euphratica during the experiment. Maximum values of height and diameter were measured in the hybrid genotype. Because of morphological properties of the hybrid trees such as straight trunk and high diameter, they could be exploited in wood production among these three genotypes. Moreover, the survival rate of hybrid of P. euphratica with P.alba was higher than other poplar genotypes. Therefore, these hybrids could be introduced as promising genotypes for forest rehabilitation and wood farming projects