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Bitter fennel (Foeniculum vulgare var. vulgare) is a commercial subspecies of fennel that is widely used in food, pharmaceutical, and perfume industries. Despite the economic importance of this crop and a growing demand for its products, most farmers cultivate local bitter fennel populations that are not necessarily high-yielding. Genetic variation in bitter fennel and relevant heritability studies have suggested that selection can be an efficient breeding method to increase bitter fennel yield. This experiment was conducted in the College of Aburaihan, University of Tehran, Pakdasht, Iran, from 2010 to 2014. Fifty fennel populations from different parts of Iran were collected and assessed for their maturity habit, life span, seed yield, essential oil content, and essential oil yield in a five-year field experiment. Results showed that these fennel populations, based on their maturity habits, comprised three distinctive groups of early, intermediate, and latematuring, requiring 120, 175, and 230 days from seedling emergence to seed harvest, respectively. The life span of the fennel populations ranged from three to four years. In general, fennel populations in arid regions with extreme temperatures in summer and winter were earlymaturing and had shorter life spans. Populations in humid or semihumid regions with a rather temperate climate were late- or intermediate-maturing and had longer life spans. These observations showed how the causes of growth limitation such as extreme seasonal temperature changes, water accessibility, and competition for sunlight have shaped the phenological features of these fennel populations. During the first three years of the study, considering the minimum life span of all populations, essential oil yield among the early-maturing fennels ranged from 2.5 to 104.6 L ha-1 year-1 (average 26.1±0.1). The essential oil yield ranged from 10.1 to 152.2 L ha-1 year-1 (average 67.7± 1) in intermediate-maturing fennels and from 7.5 to 160.9 L ha-1 year-1 (average 46.4±0.2) in late-maturing fennels. Populations with four and five-year life spans had a dramatic decrease in yield after the third year, although they produced considerable amounts of green biomass. Regarding average values in three years, the highest essential oil yield a mong early-maturing fennels occurred in the Fasa population (51.4 L ha-1), among intermediate-maturing fennels in the Meshkin Shahr and Moqhan populations (140.5 and 124.9 L ha-1, respectively), and among late-maturing fennels in the Sari population (52.1 L ha-1). Identifying high-yielding early- and intermediate-maturing populations provides a platform for further evaluations on high-yielding fennel populations with stable performance in future studies. [ABSTRACT FROM AUTHOR]

In most procedures that involve gene cloning, after the amplification of a target gene by PCR or by Real-time PCR, the purification of the trapped gene on agarose gel is a crucial stage. There are various methods for extracting genes from agarose gel by removing other contaminants. We isolated the amplified PqHMGR gene (derived from Ginseng (Panax quinquefolius)) from agarose gel by a quasi-electrophoresis device (similar to electro-elution technique). Moreover, the efficiency of this new approach was compared with that of the commercial kit 'Silica Bead DNA Gel Extraction' (Thermo Scientific American Company). Ligation to the PTG- 19 plasmid and cloning in E. coli bacteria were also done. The results showed successful isolations of targeted DNA, along with a high efficiency in producing recombinant DNA and in concluding a successful cloning procedure through this new device. The invented method provided a better purification ability than the commercial kit, but because of using the TAE 1X buffer as the purified gene storage solution, the plasmid and bacterial transformation rates were slower than the commercial kit method. It was found that using the new method for the purification of nucleotide sequences by electrophoresis and electrophoresis buffer is feasible, and that these purified fragments can be applied in cloning and sequencing. Using the TAE 1X buffer instead of distilled water did not cause problems in gene binding to PTG-19 plasmid. It also allowed a successful transformation of E. coli bacteria by the modified plasmid. Nonetheless, using TAE 1X buffer reduced the modification rate of the PTG-19 plasmid and decreased the rate of E. coli transformation by the modified plasmid. [ABSTRACT FROM AUTHOR]

Development of cultivars with high yield under normal conditions and maintaining their yield under abiotic stresses is the main purpose of plant breeding programs in arid and semi-arid areas. The present study aimed to evaluate the yield stability of a collection of commercial melon varieties under drought stress. The trial was conducted in a field under normal conditions (plants were irrigated after 50 mm evaporation of a class A evaporation pan) and drought stress conditions (irrigation was carried out after 100 mm evaporation of a class A evaporation pan). In average, 3.32 kg fruit/plant and 2.76 kg fruit/plant were obtained under normal and drought stress conditions, respectively. The highest reduction in yield as the consequence of drought exposure was recorded for 'Mazandarani' (52%) and 'Samsoori' (48%). The most drought-tolerant genotypes were 'Mamaghani', 'Nahavandi', 'Shadegan', 'Crenshaw' and 'Suski-e-Sabz' as they had constant yield under both growing conditions. On the other hand, 'Samsoori' and 'Saveh' were the most sensitive genotypes to drought. For most of the measured traits, the values of broad-sense heritability were over 0.50 i.e. there was a large genetic diversity among melon genotypes. This variation can be utilized for selecting high potential fruit yield and drought-tolerant genotypes. Total soluble solids (TSS) (aBrix) was 15.2% for 'Honey- Dew'. TSS (aBrix) was obtained 10.7, 10.09, and 9.2% for Iranian genotypes of 'Khatooni', 'Samsoori', and 'Saveh', respectively. In conclusion, although some Iranian melon genotypes were recognized as drought tolerant, they need to be improved for TSS (QBrix). [ABSTRACT FROM AUTHOR]

Pre-harvest sprouting is a concern in malting barley (Hordeum vulgare L.) in areas with a high amount of rainfall, as it decreases grain yield and malt quality. Thus, we investigated the changes in initial germination and the rate of dormancy loss in seeds of 20 promising barley genotypes at seven locations for two years (2013–2015) in Iran. Initial germination ranged between 5.23% (genotype "Teran 78/1-BC-80,411") and 38.45% (genotype "CIRU/M111") at the maturity. In several genotypes, there were negative associations between initial germination and the average temperature in March, April and May. The rate of dormancy loss and precipitation were negatively correlated in 14 genotypes in March. Thus, a hot and dry condition during seed development can decrease initial germination but can increase the rate of dormancy loss in barley. A genotype with high initial germination is suitable for cultivation in regions with a dry climate during grain development, and a genotype with a high rate of dormancy loss is appropriate in a climate with high rainfall and relative humidity. In conclusion, breeding programs must link dormancy intensity of target barley and environmental conditions (air temperature and humidity) that the crop will experience. [ABSTRACT FROM AUTHOR]

The sugarcane germplasm collection located in Khuzestan, Iran, is one of the most important genetic resources with valuable accessions from different continents. However, this collection has not been properly used by breeders due to the extremely large population. The aim of this study was to phenotypically characterize the sugarcane germplasm and form a mini-core collection. Hence, 13 morphological traits were evaluated on 253 accessions. The primary germplasm was grouped into 10 clusters based on partial repeated bisection (RB) data, where the smallest cluster contained three accessions from two breeding centres (USA and Cuba). Using principal component analysis (PCA), the first two PCs (principal component) explained 59.5% of the total variation. A mini-core of 21 accessions was created by using the maximization strategy, with a low mean difference percentage (MD = 2.31%) and large coincidence rate of range (CR = 93.96%). The sugarcane mini-core represented the major diversity of the primary collection. The means and medians between the mini-core and the primary collection did not differ significantly. Accessions with high sugar and cane yield, originating from the USA, Cuba, Argentina, and South Africa, were in the mini-core collection. In this paper, we established, for the first time, an applied mini-core collection in sugarcane germplasm. The mini-core collection, as a breeding collection, is a highly suitable, manageable, and efficient subset for the enhanced use of sugarcane germplasm in breeding programs. [ABSTRACT FROM AUTHOR]