SEED AND PLANT IMPROVEMENT JOURNAL
Year:2013 | Volume:29-1 | Issue:1|Papers Count:14

To assess the drought tolerance in advanced durum wheat lines, 20 genotypes were evaluated in a randomized complete block design with three replications under non-stress and drought stress conditions during 2009-2010 cropping season. Analysis of variance showed significant differences among genotypes for grain yield in two environmental conditions (non-stress and stress). The maximum grain yield under stress and non-stress conditions belonged to lines No. 13 (808.3 gm-2) and No. 14 (1177 gm-2) respectively. Investigation of correlation between yield in two conditions and drought resistance indices showed that STI, MP and GMP were desirable for identifying high yielding genotypes in two conditions, and the best index was STI. According to drawing of bi-plot, the genotypes were placed into tolerant and non-tolerant groups, as genotypes No.4, 5, 10, 11, 14 and 15 were placed in area with high yield potential, low sensitive to drought, and near to MP, GMP and STI vectors, and genotypes No.6, 16, 17, 19 and 20 were placed in area with low yield and high sensitive to drought. Based on cluster analysis and discrimination analysis according to desirable indices (MP, GMP and STI), genotypes were divided into 5 different groups. Finally based on drought resistance indices genotype No. 14 was determined as drought tolerant genotype.

In order to evaluate late maturity maize hybrids along with their parents to fusarium ear rot, an experiment was carried out in Karaj and Sari Research Stations in 2009 and 2010 with 22 lines and hybrids. All ears of plants were inoculated by nail punch technique at flowering stage. At physiological maturity, evaluation was conducted by using disease severity index (1-6). The results demonostrated the importance of the role of parents inresistance of the hybrids. The results of combined analysis showed that there were significant differences among hybrids and parents in disease severity of fusarium ear rot in both years. Most of hybrids were moderately resistant to disease including hybrid K360.3 × K18 (KSC705). Two hybrids K166B × K18 and K3547.4 × MOl7 (KSC706) were evaluated as resistant genotypes to the disease.

Utilization of genetic variability in different levels of wheat gene pool as a rich reservoir of useful traits has been recently come in to consideration. Synthetic wheats are used as a bridge for transferring of desirable genes from wild relatives. One hundred synthetic wheat genotypes from CIMMYT present in the Cereal Research Department. collection were evaluated along with three checks (Pishgam, Pishtaz and Moghan-3) for different traits in an observation experiment during 2009-2010 cropping season at Seed and Plant Improvement Institute, Karaj, Iran. Each genotype was planted in two lines of 1m long. The checks were repeated between the rows, every 20 genotypes. Descriptive analysis of data showed presence of a vast genetic variability among the genotypes for the recorded traits. Stepwise regression analysis showed that grain no. per spike and biological yield had positive and significant effects on yield and remained in the final model with adj. R2~70%. Cluster analysis using ward method grouped the synthetics in seven groups. Based on field evaluations and data analysis 15 synthetic wheats were selected for further evaluation. The results indicated that synthetic wheats are valuable genetic materials as a source of new variability to be added into wheat gene pool.

In order to quantify GEl effects on the seed yield of 17 spring safflower genotypes and to identify stable genotypes under rain-fed conditions, multi-environment yield trials (MET) were conducted for four consecutive years (year-location combinations during 2003-06) at nine research stations in Iran. The results indicated that all factors (environment, genotype, interaction) were significant in this MET as judged by ANOV A, by Hildebrand procedure for non-crossover interaction (no change in genotypic rank) and by the de Kroon/van der Laan test for crossover interaction (change in genotypic rank). According to the results of all Huhn and Tennarasue nonparametric methods, genotype no. 11 (Gila) was found as the stable genotype. In addition, genotype no. 15 (Sina) was the most stable genotype among the others according to Fox et al. superiority index. Based on yield-stability statistic (YSi), genotypes no. 2 (S-541), 15 and 4 (Syria) were selected as the most stable genotypes in all environments. The GGE biplot analysis revealed that genotypes no. 15, 1 (Cyprobergon) and 4 were both high yielding and stable. GGE biplot and YSi identified genotype no.15 (Sina) as the most desirable genotype across years.

In this study, direct shoot regeneration of three alfalfa cultivars was investigated. Stem nodal explants isolated from in vitro germinated seedlings were cultured on Murashige and Skoog (MS) basal medium with Gamborg’s B5 vitamins supplemented with different concentrations and factorial combinations of BAP/NAA or TDZ/AgN03. The analysis of variance revealed highly significant (P< 0.01) differences among the cultivars and among the different levels of growth regulators in view of shoot buds induction and regeneration. The maximum average number of induced shoot-bud (5.80 buds per explant, the average of three cultivars) and regenerated shoot (5.73 shoots per explant, the average of three cultivars) was achieved with the higher level of BAP (1 mgl-1) and NAA (0.2 mgl-1), while the maximum values (5.77 and 5.69 shoot buds and regenerated shoots, respectively) were obtained with the lowest level of TDZ (0.01 mgl-1) along with 3 mgl-1 AgN03 Cultivars Ghareyonjeh, Hamedani and Ordobad were ranked, respectively, from point of view of shoot development and regeneration potentials. Regenerated plantlets were remarkably rooted on half-strength MS medium supplemented with 1.5 mgl-1 NAA and 1 mgl-1 IBA and rooted plants were acclimatized successfully in the greenhouse with a survival rate of 100%. The simple, rapid and efficient regeneration protocol presented in this study can be used in breeding programs as well as for genetic engineering of a wide range of Medicago species.

In order to evaluate grain yield potential of bread wheat lines in salinity condition, modeling of grain yield and selection of best genotypes to use in breeding program, a collection of 100 diverse bread wheat lines, including sensitive and tolerant to salinity were grown in an incomplete block design (lattice) in salin and normal field conditions in Yazd and Kerman. Results of combined analysis of different traits showed significant differences among genotypes. Results of correlation study determined that there was significant differences among yield and majority of traits. Stepwise multiple linear regressions showed that in salin stress condition, number of seeds per spike, seed weight in spike and days to tillering had the most effective role on yield. Results of factor analysis indicated importance of biological yield, harvest index and yield components in salin stress condition. Path analysis based on entered variables in final step of stepwise regression indicated that number spike per m2 and seed weight in spike in stress environment had high direct effect on yield. It can be concluded that, lines number 26, 48, 51, 54, 55, 59, 60, 66, 67, 69, 73, 75, 87, 89 and 94 that had higher yield than the high yielding check cultivars Arg, Bam and Kavir, were identified as the promising lines and were selected for next molecular, physiological and adaptability studies.

Lettuce (Lactuca sativa L.) is one of the major leaf and salad vegetables. Identification of the genetic potential of lettuce germplasm is crucial in the breeding programs and introduction of new cultivars. Assessment of genetic diversity of Iranian lettuce gennplasm collected from different provinces was conducted in the research field of Seed and Plant Improvement Institute, Karaj, Iran in 2010. Genotypes were sown on rows with the length and spacing 3 m and 60 cm, respectively. Morphological characteristics were evaluated based on IPGRI descriptors. Results revealed high variability among genotypes. Three types of lettuce including stem, leaf and romaine were identified for the first time in Iranian lettuce. There were significant positive correlations between growth period to bolting and flowering in genotypes. Qom genotype and lines no. 15and 25 of Mazandaran were sensitive to bolting, and Pich-e-Ahvaz, Siah-e-Dezful, Sefid-e-Neishabour, Siah-e-Neishabour and Varamin 3 were resistant. Genotypes were separated into three groups based on cluster analysis in which some groups had above average values for some traits. Factor analysis reduced the 17 evaluated traits to six components which justified 71.8% of changes. Distribution diagram based on the first and second components separated the genotypes into three groups. To conclude, genotypes with desirable characteristics can be used in breeding programs of lettuce in Iran.

Iran is one of the most important genetic diversity sources of Onobrychis genus and the annual species Onobrychis crista-galli is a pasture plant that is distributed in western and southern regions of Iran. Twenty six genotypes of O. crista-galli were collected from different habitats. Their genetic variation was evaluated based on morphological characteristics in a randomized complete block design with three replications in the experimental field at Seed and Plant Improvement Institute, Karaj, Iran in 2010- 2011. Analysis of variance showed significant differences for all the studied traits indicating that there was genetic variation for the traits among the genotypes. For peduncle length, a high variation and for pod width, a low variation was found in quantitative traits. Using Shannon index in qualitative traits, plant hairiness and growth habit showed the highest and the lowest diversity respectively. The pod and seed weight showed positive and significant correlation with leaflet number per leaf and days to 50% flowering. Cluster analysis by Ward method divided all genotypes into four groups. The most differences, based on the most important morphological traits, were detected between groups 2 and 4. Based on the results of the present investigation, crossing between the individuals of these groups can provide a vast genetic variability which can be used in development of new high yielding lines and cultivars.

The present study was carried out to compare, categorize and select the superior genotypes of apricot among 32 native cultivars and genotypes collected in Kamalshahr Collection Garden, Seed and Plant Improvement Institute, Karaj, Iran. Twenty one morphological characteristics in each genotype were evaluated during two years (2008 and 2009) using UPOV descriptor. Based on the results of analysis of variance, all characteristics were significant indicating a vast variability among the genotypes. Results of the simple correlation analysis showed significant positive or negative correlations among some important traits. The highest correlation was detected between fruit lateral width and fruit height. Factor analysis was used to define the determinat factors and traits constituted in each factor. Mean comparison of traits showed that Hessgoli and Shahroud 58 genotypes had the highest and genotype Tabazeye Marand had the lowest weight of ten fruits. Cluster analysis on twenty important factors divided genotypes into two main groups in the distance of 25. The smaller group consisted of four genotypes Shahroudi 32, Shahroudi 13, Naderye Karaj and Karaj Nouri. Generally, the results of this study showed that assessment of morphological and pomological characteristic can differentiate apricot genotypes well and bring the similar genotypes in one group.

In order to evaluate the heterosis and combining ability of petunia inbred lines for ornamental traits, 12 hybrids were derived from direct and reciprocal crosses of 4 petunia inbred lines viz. L5 (PI), L8 (P2), L11 (P3), and L17 (P4). In the second year, the derived hybrids and their parents were planted in a randomized complete block design with three replications. The measured traits in F1 generation were, plant height at first flower, number of flower per plant, days to flowering, flower diameter, flower tube diameter, flower tube length, flower length, flower longevity and flower fragrance. The significance of specific combining ability (SCA) and general combining ability (GCA) for the most studied traits revealed that both additive and non-additive gene effects contributed to the inheritance of the traits. Not statistically significant of GCNSCA ratio and the degree of dominance more than one showed that the contribution of non-additive gene actions was relatively higher than that of additive for all studied traits. For flower diameter, parent P2and hybrid P 1 × P2 had the highest GCA and SCA effects, respectively. Reciprocal effects were significant in all measured traits except for flower longevity and flower length. Estimation of heterosis showed that combinations P 1 × P3 and P2 × P3 had the highest heterosis relative to mid and high parents for flower number and diameter among all hybrid combinations, respectively.

In this study, genetic variation of 238 genotypes of Iranian sour pomegranate (Yazd Pomegranate Collection) was studied based on single sequence repeated (SSR) markers. In order to assess the genetic relationships and population structure. Cluster analysis was performed by methods UPGMA and NJ with Mega4 software, structure analysis model based Bayesian by Structure 2.2 software and principal coordinate analysis (PCoA) with Ntsys software. SSR-MP26 and SSR-MP39 showed the highest (0.907) and lowest (0.544) PIC, respectively. Results of all mentioned methods showed that genotypes are generally clustered independently from their geographical origins and their proposed denomination suggesting that severe admixture in studied samples. These results showed that Yazd pomegranate collection might contain divergent pomegranate genotypes with analogue names or vice versa and needs to be confirmed by future studies.

Sclerotinia stem rot (white stem rot), an important fungal disease, which is caused by Sclerotinia sclerotiorum, is one of the serious diseases of various plants such as canola. Use of resistant cultivars is an effective method to control the disease. A greenhouse experiment based on cotyledon inoculation using mycelial suspension of two different isolates of S. sclerotiorum was conducted to evaluate 12 canola cultivars (including seven spring type and five winter type) against the pathogen. The results demonstrated that response to S. sclerotiorum was significantly different among cultivars (P = 0.05). Interaction between isolates and cultivars was also significant (P = 0.05). Hyola 401 with the highest and Zarfam with the lowest infections, were the most susceptible and the most resistant cultivars, respectively. The results of this experiment showed that cotyledon test is a reliable and rapid method for screening canola cultivars against white stem rot fungus.

To evaluate yield and some quantitave and qualitative characteristics of tomato cultivars in warm climate of southern provinces of Iran and to determine suitable cultivars for these regions, sixteen cultivars were evaluated in an experiment using randomized complete block design with three replications in Minab, Hormozgan province. Seeds were sown in 105 cells tray cultures containing peat moss in September and seedlings were transplanted in mid Octeber. Cultivars consisted of Lesto, Kimia, DFT3000, DFT3002, ZD731, ZD625, ZD633, ZD634, ZD61O, 9014, T97301, RFT112, TUS33812, TH1462 and Sunseed 6089 (Check cultivar). Morphological and agronomic traits were evaluated based on descriptor of tomato. Yield and qualitative traits such as Brix, Vitamin C, pH and resistance to common fungal and viral diseases were also recorded. The results of evaluations showed generally that cultivars RFT112, Kimia and ZD633 had higher yield, better quantitative and qualitative characteristics and satisfactory levels of resistance to diseases and were determined as suitable cultivars for Minab and regions with similar climatical conditions.

Northern regions of Khuzestan province are suitable areas for soybean cultivation. Hybridization blocks and soybean segregating generations were established in Safiabad Agricultural Research Center during 1990-1997 to produce new soybean lines which would have a high seed yield and high adaptability to the region. Line L.14 selected from segregating generations of a hybridization between cultivars Safiabad and Duglas, showed better perfprmance among 14 lines selected from generations of this hybridization. In a two years yield trail carried out in 1999 and 2000, line L.14 produced 3977 kgha-1 seed yield which was 33% higher than that of check cultivar Semmes and was 14 days early aturity than the check cultivar. In different agrotechnical experiments performed in 2001-2002, this line appeared to be suitable for planting as the second crop after wheat or miaze in the region, producing up to 3900 kgha-1 seed yield. In addition to seed yield, L. 14 has about 1.38g higher 100 seed weight and 15 cm lower plant height than the check cultivar. In on farm experiments carried out in two locations in Dezful and Shoosh during sumnmer of 2002, line L.14 produced 22% higher seed yield and was 12 days early maturity than the check cultivar Semmes. Line L.14 was officially released through the Agricultural Research, Education and Extension Organization and named Salend, for cultivation in northern regions of Khuzestan, South west of Iran.