فصلنامه علوم زراعی ایران
سال چهاردهم شماره 3 (پیاپی 55، پاییز 1391)

To assess the effects of terminal drought stress on phenological traits, grain yield, yield components, and to determine phenotypic variation and relationship between grain yield with other traits in 64 Kabuli genotypes an experiment was carried out using simple lattice design (8×8) under two conditions (terminal drought stress and normal) in 2011 at Research Field of Faculty of Agriculture, University of Tehran, Karaj, Iran. Results showed that there were significant differences among chickpea genotypes which revealed genetic variation for different traits. According to the results of phenotypic correlations, stepwise regression, path analysis for both normal and stress conditions, it can be concluded that, expected that biological yield and harvest index, seed and pod weight, number of filled pods, number of seed.plant-1, 100 seed weight and number of seed.pod 1 were the most important and effective traits affecting yield. Therefore selecting and breeding for these traits could be considered for improving grain yield in Kabuli chickpea. Based on factor analysis using data in both conditions four factors were selected that explained 78.96% and 81.6% of total variation under normal and drought stress conditions. The first and second factors were introduced as yield and yield component factors. Genotype grouping in both conditions was conducted using UPGMA method and the square Euclidean distance. Genotypes were grouped in three clusters in both conditions.

Integration of foreign genes into plastid genomes occur through homologous recombination between flanking sequences of gene in plastid vectors. In this study, by analysis of plastid genomes using bioinformatics databases, we succeed to select a region of plastome as alien gene targeting sequence including the appropriate length for homologous recombination and integration in plastome, specific plastid origin of replication, targeting gene to inverted repeat region of plastid genome and unique restriction enzymes recognition sites in the center of flanking region sequences for alien gene integration. Since similarity (%) of the flanking region sequences would increase transformation efficiency of plastome dramatically, therefore, a pair of primers was designed to isolate the plastome flanking regions. These primers were100% similar to all plant plastomes, but the length and sequence of their amplified fragments were variable in different plant plastomes. Flanking region sequence from tobacco, cotton, corn, lettuce, tomato, carrot, and even the canola and lemon plastomes that still their plastome sequences are not available in Gene Bank were isolated and cloned. The accuracy of cloning, present and direction of flanking regions fragment from different plant plastomes were confirmed by enzymatic digestion analysis using HindIII and BamHI. Then different types of chloroplastid vectors using different regulation elements were constructed. The regulation elements that could be used for efficient expression of any alien genes in different plastids were including plastid constitutive or inducing promoters and terminators, suitable untraslated regions, Ribosome binding sites of plastid, suitable restriction enzyme recognition sites for cloning and expression of desired gene in single or polycistronic status, reporter genes, antibiotic or non-antibiotic markers and sequences for removing of marker gene. These recombinant chloroplast plasmids including pFNGi and pFNG can be used as universal and specific vectors for chloroplast transformation. Thus, in this study we succeeded to design the high efficient and specific plastid vectors, not only for plants which their plastomes were completely sequenced, but also for other plant species that there is not any sequence of their plastomes availaable in databanks.

Two BC2F4 populations of rice, Hashemi/IR67418-110-3222 (Hashemi/IR-22) and Hashemi/Neda, Hashemi was as recurrent parent, were studied during two years (2009 and 2010) for QTLs detection for plant height, days to 50% heading, growth duration and yield. The role of epistasis and QTL-environment interaction on these traits was also studied. Hashemi/IR-22 and Hashemi/Neda lines were tested with 61 and 65 polymorph SSR primer pairs, respectively, which were distributed on all chromosomes. The total genetic maps lengths of Hashemi/IR- 22 and Hashemi/Neda were 1103.45cM and 1260.53cM, respectively. Four to five QTLs were detected for each trait in Hashmi/IR-22 population with at least two QTLs repeated for each trait during two years. These QTLs explained 5.6% to 37% of the traits phenotypic variation. In Hashemi/Neda population three to four QTLs were detected for each trait, with at least one QTL repeated for each trait during two years. These QTLs explained 5.1% to 43.2% of the traits phenotypic variation. From detected QTLs, only a plant height QTL flanked by RM234 marker on chromosome 7 and a yield QTL flanked by RM3337 and were the same in the two populations. This indicated the important role of genetic background effect on controlling these traits. In each population there were QTLs that simultaneously affected two or more of the studied traits, e. g. plant height, days to 50% heading, growth duration and yield, which suggested pleiotropic or linkage gene effects for these traits. Two QTLs on chromosomes 6 and 8 for growth duration and QTL on chromosome 8 for yield in Hashemi/IR-22 population and one QTL on chromosome 6 for days to 50% heading and growth duration and one QTL on chromosome 3 for yield in Hashemi/Neda showed interaction with environment. Also in each population a pair of QTLs was recognized with significant epistatic effect.