Age-dependent atrial arrhythmic phenotype secondary to mitochondrial dysfunction in Pgc-1β deficient murine hearts

Introduction: Ageing and several age-related chronic conditions including obesity, insulin resistance and hypertension are associated with mitochondrial dysfunction and represent independent risk factors for atrial fibrillation (AF). Materials and methods: Atrial arrhythmogenesis was investigated in Langendorff-perfused young (3–4 month) and aged (>12 month), wild type (WT) and peroxisome proliferator activated receptor-γ coactivator-1β deficient (Pgc-1β ) murine hearts modeling age-dependent chronic mitochondrial dysfunction during regular pacing and programmed electrical stimulation (PES). Results and discussion: The Pgc-1β genotype was associated with a pro-arrhythmic phenotype progressing with age. Young and aged Pgc-1β hearts showed compromised maximum action potential (AP) depolarization rates, (dV/dt) , prolonged AP latencies reflecting slowed action potential (AP) conduction, similar effective refractory periods and baseline action potential durations (APD ) but shortened APD in APs in response to extrasystolic stimuli at short stimulation intervals. Electrical properties of APs triggering arrhythmia were similar in WT and Pgc-1β hearts. Pgc-1β hearts showed accelerated age-dependent fibrotic change relative to WT, with young Pgc-1β hearts displaying similar fibrotic change as aged WT, and aged Pgc-1β hearts the greatest fibrotic change. Mitochondrial deficits thus result in an arrhythmic substrate, through slowed AP conduction and altered repolarisation characteristics, arising from alterations in electrophysiological properties and accelerated structural change.We acknowledge financial support from the Medical Research Council (MR/M001288/1), the Wellcome Trust (105727/Z/14/Z), British Heart Foundation (PG/14/79/31102 and PG/15/12/31280), Sudden Arrhythmic Death Syndrome (SADS) UK, The McVeigh Benefaction and the Fundamental Research Grant Scheme, Ministry of Education, Malaysia (FRGS/2/2014/SKK01/PERDANA/02/1)

Outlook on vegetable production in Turkey

Although a spectacular development realized in recent years in industrial and service sectors, agriculture still retains its important role in the economy of Turkey. Agriculture provides about 35% employment within the working population and ensures 14% of GNP. Vegetable growing is one of the most dynamic activities in agriculture and horticulture. The total vegetable production is nearly 30 million tons, potatoes included, produced on approximately 1.2 million ha. There is a linear increase in the production and growth rate is 3.5% per year. About 75% of produced vegetables are consumed freshly in the country, 22% of them are used in processing and 3% is exported. Half of the processed products is exported. The main vegetable growing areas are the Mediterranean, the Aegean and Marmara's coastal regions. 85% of total production is realized on open field and 15% under protection. Greenhouses and plastic tunnels areas reached 30 and 23 thousand hectares, respectively. Protected cultivation is mainly located in Mediterranean Region. Vegetable growing enterprises are very small and this situation cause serious difficulties in mechanization and commercialization. A new tendency in recent years is the establishment of big and modern farms, especially for greenhouse growing. The Turkish Ministry of Agriculture and Rural Affairs promotes modernization of techniques and technologies used in this sector as well as seed and nursery business

Effects of plant density and number of shoots on yield and fruit characteristics of peppers grown in glasshouses [Bitki Yogunlugu ve Sürgün Sayisinin Sera Biber Yetiştiriciliginde Verim ve Meyve Özellikleri Üzerine Etkileri]

Plant density and pruning systems play a key role in the effective use of the area inside the greenhouse. Pepper (Capsicum annuum L.) cultivars. Amazon-long green and Balo bell-shape type, were grown in the winter cultivation period in a glasshouse. A constant space of 80 cm between rows with different within-row spacings (45 cm, 30 cm and 15 cm) and shoot numbers (between one and four shoots per plant) were applied to optimize plant density and number of shoots. Wider within-row spacing and higher shoot numbers per plant increased the number of leaves. However, the individual leaf blade area was higher for narrower within-row spacings with fewer shoots. While higher plant densities with a greater number of shoots reduced photosynthetically active radiation, they increased the leaf area index at fruiting level. In order to obtain high yields an assumption of 80 × 15 cm with two shoots per plant is suggested for peppers. When expensive seed is used then a 80 × 30 cm spacing with three shoots per plant might be more economical. Plant density and the number of shoots did not affect fruit quality characteristics, such as fruit weight, length, diameter, volume, dry matter, total soluble solids and the pH of the flesh in either cultivar

Determination of a suitable formula for the calculation of sum growing degree days in watermelon (citrullus lanatus (thunb.) mansf.)

The purpose of this study was to explore the possibility of adaptation to watermelon of the temperature sum methods by the calculation of the Sum Growing Degree Days (SGDD), which was already used successfully in other crops. In the experiments, ten watermelon cultivars which express various degrees of earliness were used. These genotypes were sown at various dates and the experiments were carried out for two successive years. Variations in the daily temperatures were created under different growing conditions i.e. greenhouse, high tunnel, low tunnel and the open field. The duration of the period from sowing to harvesting date as well as temperatures encountered were recorded, for all the experiments. All the total SGDDs were calculated by three different models using the temperatures of three daily maximums i.e. 30°C, 32°C and 35°C and four bases i.e. 10°C, 13°C, 15°C and 18°C, being 36 equations altogether. The F test was applied to the data obtained and CVs were calculated. The formula, i.e. SGDD=Z(Tmax+Tmin)/2-Tb, (Tmax+Tmin)/2)>Tb, using 18°C as the base temperature (Tb) was determined to be the most suitable compared to the rest

Relationship between earliness and some morphological characters in watermelon (citrullus lanatus (thunb.) mansf.)

Relationship between earliness and some morphological characteristics in watermelon were investigated. A total often genotypes belonging to very early, early, mid-early, late and very late fruiting groups were used in the experiment. The earliness (number of days from sowing to first fruit maturation) of the tested varieties was determined by cultivating in greenhouse, high plastic tunnel, low plastic tunnel, and open field. Duration of emergence (day), cotyledon length (mm), cotyledon width (mm), the nodes where the first male and female flowers occurred and average leaf area (cm2) of the plants were determined The correlation and regression between the investigated characteristics were calculated. Significant and reliable correlations (P>99%) were determined between the earliness and hypocotyl length (r=0.92), cotyledon length (r=0.82), cotyledon width (r=0.77), nodium occurring the first male flower (r= 0.76) and the odium occurring the first female flower (r=0.95). Reliable correlations were not determined between the emergence duration and earliness and leaf area and earliness

In situ development of in vitro derived haploid and doubled haploid cucumber plants

Haploid and doubled haploid plants are valuable materials for genetic and cytogenetic studies as well as for plant breeding purposes. Several in situ and in vitro methods are being studied to obtain high frequencies of haploids and doubled haploids in vitro, development patterns of which appear to be similar. It was our aim, that in case in situ development pattern is different from that of in vitro, to determine plant characteristics and some morphological features of the haploids and doubled haploids after transplanting to soil to be grown under greenhouse conditions. Marked differences were observed and illustrated between the cucumber plants from the both ploidy level. These differences were mainly on plant height, lateral branching, length of internodes, flowers, anthers, pollen production and fruit set. It was also determined that some of the characteristics studied were dependent on either the open pollinated or the hybrid origin of the plants

Determination of a suitable formula for the calculation of sum growing degree days in cucumber

This study was conducted to determine the most suitable formula to calculate Sum Growing Degree Days (SGDD) in Cucumber for the periods between sowing and emergence, emergence and anthesis, anthesis and maturation, sowing and first harvest periods. In a two year trial, six cultivars were grown, starting from different sowing dates, and 96 equations were evaluated by using different combinations of daily ceiling (26, 28, 30 and 32°C) and base (0, 8, 9, 10, 11, 12, 14 and 16°C) temperatures originating from the following four main formulas: SGDD= ?(Td-Tb); Td>Tb Formula [1] SGDD= ?(Tmax-Tmin)/2-Tb; (Tmax-Tmin)/2>Tb Formula [2] SGDD= ?(Td-Tb)xDaylength; Td>Tb Formula [3] SGDD= ?[(Tmax-Tmin)/2-Tb] xDaylength; (Tmax-Tmin)/2>Tb Formula [4] According to the results, Formula [1] with 8 or 12°C base temperatures were more suitable than the others in the calculation of SGDDs for all stages of growth

Effect of colchicine treatment with different doses and periods on in vitro chromosome doublication in haploid watermelon [Haploid karpuzda in vitro kromozom katlanmasi amaciyla degişik doz ve sürelerde uygulanan kolhisinin etkisi]

Differents colchicine doses (0.5% and 1%) and treatment periods (1, 2, 4 and 6 hours) were tested in vitro conditions in order to obtain dihaploid lines from parthenogenetic haploid plants which achieved by irradiated pollen. Treatments were made to 3-4 weeks age in vitro microcuttings of Sugar Baby, Halep Karasi and Crimson Sweet varieties. 64 percent of the plants treated with 0.5% colchicine stayed alive and 56% of the plants were developed into a new plant. At the doses of 1% the rate of alive and growing plant decrease to 40%. As for as the treatment periods were considered the highest death were observed from the 6 hours treatment. Results showed that in order to obtain dihaploid lines by colchicine treatment for either 4 hours at 0.5 % or 2 hours at 1 % for microcuttings were the most favorable condition. Higher doses and long period treatment resulted in death plant and low doses and short period treatment didn't change the ploidy level

Effects of the low tunnel and sowing dates on the yield, plant growth and some agronomic characteristics of sweet corn (Zea mays L. var. Saccharata) [Alçak tünel uygulamasi ve farkli ekim zamanlannin şeker misirda (Zea mays L. var. Saccharata) verim, bitki büyümesi ve bazi agronomik özellikler üzerine etkileri]

The effects of the low tunnel on the yield, the earliness, plant growth and the agronomic characteristics of the sweet corn that was sown at three different sowing times within 10 days intervals since February 12th were studied. The first emergence, the full emergence and the silking time of plants from sowing time were determined during two years. Also, some other characters such as the total yield, the early yield, the ear weight with or without husk, the ear length, the ear diameter, the number of kernels per ear, the weight of kernels and TSSC (%) were investigated. The first emergence, the full emergence, and the male flowering dates were verified in sowing periods respectively. The low tunnel application gained approximetly 14, 8 and 7 days earliness in respect to the full emergence at the first, the second and the third sowing period respectively. Both sowing periods and the low tunnel application affected the earliness importantly, but the effect of the low tunnel was important than that of sowing dates. Different sowing dates didn't affect the total yield, however the tunnel aplication increased the early yield (20 %). The effect of the low tunnel on the yield was the result of the increase of the ear weight. Low tunnel application changed the crop quality significantly, but different sowing dates didn't change the quality of crop significantly