Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research
Year:2000 | Volume:- | Issue:1|Papers Count:6

Investigation on appropriate conditions for propagation of Rosa damascene was started with study of rooting in cuttings as a prerequisite to successful vegetative propagation. To do this an effort was made to propagate 55 out of 80 genotypes of this plant using stem cuttings in sand. Regular irrigation and weed control were also accomplished. Another experiment was carried out using tap water instead of sand culture for rooting of two of the above genotypes under dark or light with daily replenishment of water. Many of the tested genotypes did not root and only 7 genotypes showed rooting capacity with the rates of 50, 24, 12, 10, 6, 5, 5, and 5 percent in sand. However, rooting occurred successfully in both genotypes in tap water, none of which rooted in sand.It could be concluded from these studies that there is a wide variation in rooting potentiality between different genotypes. In addition to .the internal factors, which may differ according to genotype, external factors such as rooting media or environmental conditions can also affect rooting capability. Thus, the investigation is required to be continued in order to study the plant internal factors, their genetic control, and also external factors, which could affect adventitious root formation in the plant.

This study was carried out to determine extent and nature of genetic and non-genetic relationship between some plant characters and to determine selection indices for a selection program in 10 populations of sainfon (Onobrichis sativa) using the best combination of the attributes and their utilization in an indirect selection. Ten accessions, randomly taken from existing accessions of the Forests and Rangelands Gene Bank were used in this study. Accessions were sown in a randomized complete block design with 3 replications. Ten quantitative morphologic and phonologic characters were recorded from seven individual plants per plot. Genetic variance component of the characters were estimated using expected mean square from the table of analysis of variance. This was used to estimate broad sense heritability. The variance covariance matrices were estimated for each of the total, replication, treatment, error and genetic components of variance for treatments using analysis of variance and covariances. Using phenotypic and genotypic variance and covariance matrices and broad sense heritability as the relative economic value, index coefficients were estimated for different combinations of the attributes. The indices with the best genetic gain were used to estimate index value of the studied populations. 

An in vitro method was used to produce hybrid poplar plants between Populus alba L. and P. euphratica OLIV in two directions. Developed ovaries and ovules were isolated from P. alba L. female branches, Which had been, pollinated with P. euphratica pollen grains by using twig and pot breeding technique. The same procedure was carried out for isolation of developed P. euphratica OLIV ovaries and ovules which had been pollinated with Populus alba L. pollen grain on mature trees. Isolated ovaries and ovules of both crosses were then transferred to growth regulator free half concentrated MS agar medium for embryo germination. Fourteen days old Populus alba L. ovary and ovule embryos produced the highest number of plantlets, While 45 days old ovary and ovule embryos of P. euphratica OLIV were necessary to obtain hybrid plants. Maximum two to three plantlets were observed per both Populusalba L. and P. euphratica OLIV ovary culture. Ninety percent of pollinated P. euphratica OLIV and Populus alba L. ovules successfully produced plantlets, whereas the efficiency of pollinated ovaries to produce plantlets was 70% for Populus alba L. and 67% for P. euphratica OLIV.Plantlets were cultured in the same medium in jars, before being transferred to potting soil. Seventy-five interspecific P. alba L. x P. euphratica OLIV. and twenty-six of P. euphratica OLIV. x Populus alba L. hybrid plants were successfully acclimatized in greenhouse.

In order to investigate walnut (julgans regia), shoot tips and axillary buds of elite adult trees were collected from natural stands and used as explants.Suitable method of sterilization was found. Sterilized explants cultured on media with different concentration at different growth regulators. DKW medium containing BA= 1mg/lit was the best medium for shoot proliferation. GA3, promoted lateral bud growth and shoot proliferation. MS and DKW medium containing 0.25 mg/lit GA3 and 0.5 mg/lit BA, were the best composition for shoot proliferation.Shoots cultured on hormone free DKW medium before rooting treatments, were longer and more vigorous. There was no rooted shoot although many different treatments like decreasing macro elements and sucrose concentrates, using of activated charcole and adding different vitamins and amino acids to the medium have been investigated.