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241.
This study was conducted to evaluate true potato seed (TPS) technology for use in ware or seed potato production in two contrasting environments in Turkey during 2002 and 2003. The field experiments were carried out in the Hatay and Nevsehir provinces in Turkey, which represent a Mediterranean early crop potato production area and a temperate main crop potato production area, respectively. The plug seedlings of six TPS hybrids were transplanted to the fields at four densities (15, 20, 25 or 30 plants m−2). The seed tubers of the medium early cultivar Marfona were also planted in the experimental plots to compare the performance of the TPS hybrids with traditional seed tubers. Transplanting of the seedlings was significantly delayed in Hatay due to unsuitable weather conditions in both years. The seedlings needed an adaptation period of 2–4 weeks after transplanting depending on the location and the growing conditions. The adaptation period was longer in Hatay due to high air temperatures after transplanting. Although the yield performance of the TPS hybrids differed depending on the location and year, the TPS hybrids produced noticeably higher total tuber yields in Nevsehir location (ranging from 43.1 to 62.5 t ha−1 in 2002 and from 39.5 to 50.6 t ha−1 in 2003) than in Hatay (ranging from 15.3 to 19.6 t ha−1 in 2002 and from 15.1 to 19.1 t ha−1 in 2003). The percentage of marketable tubers (>28 mm) was also considerably higher in Nevsehir. The optimal plant density varied between 25 and 30 plants m−2 with regard to the total yield, while the optimal density with regard to the marketable yield was 20 or 25 plants m−2 depending on hybrids in Nevsehir. However, none of the tested plant densities caused competition between plants in Hatay, where the environmental conditions during the growing period considerably restricted the growth of individual TPS seedlings.It was concluded that transplanting of TPS seedlings can be considered a feasible alternative for ware or seed potato production in temperate environments like Nevsehir that have growing periods of at least 4 months. However, there are several obstacles, such as difficulties with the timing of transplanting, long adaptation period that threaten the practicability of TPS technology in Mediterranean-type environments. Further agronomical studies focused on reducing inter- and intra-plant competition are needed for both environments in order to improve the acceptability of TPS technology to farmers.  相似文献   
242.
Abiotic stress is a major limiting factor to crop productivity,and heat stress is one of the important elements for reduced crop production.Plants respond to heat stress at molecular and cellular levels as well as physiological level.Heat stress alters expression patterns of numerous genes in plants.At the molecular level,most of the information for heat stress response was obtained from model plants such as Arabidopsis thaliana,Medicago trancatula,and ,Oryza sativa,but little molecular research has focused on heat stress respones in cotton.  相似文献   
243.
This study aimed to determine the effect of propolis extract on quality of liquid smoked carp (Cyprinus carpio) sausage stored at 2°C for 9 weeks. Carp sausages were separated into three groups: control group, without propolis extract; second group, with 1% (w/w) propolis extract added; and third group, with 2% (w/w) propolis extract added. Propolis extract added carp sausages showed lower total volatile basic nitrogen (TVB-N) value, peroxide value (PV), and free fatty acid (FFA) content compared to control during the storage period. During 9 weeks of storage, propolis extract added carp sausages showed significantly lower total aerobic mesophilic bacteria (TAMB) and psychrophilic bacteria count (PBC) than those of control samples (p < .05). Yeast and mold were not detected in all fish sausages throughout the storage period.  相似文献   
244.
Enhancing crop water‐use efficiency (WUE) is a major research objective in water‐scarce agroecosystems. Potassium (K) enhances WUE and plays a crucial role in mitigating plant stress. Here, effects of K supply and PEG‐induced water deficit on WUE of spring wheat (Triticum aestivum L. var. Sonett), grown in nutrient solution, were studied. Plants were treated with three levels of K supply (0.1, 1, 4 mM K+) and two levels of PEG (0, 25%). WUE was determined at leaf level (WUEL), at whole‐plant level (WUEP), and via carbon isotope ratio (δ13C). Effects of assimilation and stomatal conductance on WUEL were evaluated and compared with effects of biomass production and whole‐plant transpiration (EP) on WUEP. Adequate K supply enhanced WUEP up to 30% and by additional 20% under PEG stress, but had no effect on WUEL. EP was lower with adequate K supply, but this effect may be attributed to canopy microclimate. Shoot δ13C responded linearly to time‐integrated WUEL in adequately supplied plants, but not in K‐deficient plants, indicating negative effects of K deficiency on mesophyll CO2 diffusion. It is concluded that leaf‐scale evaluations of WUE are not reliable in predicting whole‐plant WUE of crops such as spring wheat suffering K deficiency.  相似文献   
245.
This field study was conducted to compare conception and insemination efficiency responses to intrauterine polyvinylpyrrolidone-iodine (PVP-I) and antibiotic (AB) treatments in dairy cows that experienced pregnancy loss. Data were collected from lactation cows with a history of pregnancy loss 27 to 70 days post-insemination (n = 97) during the 1st to 3rd lactation (days in milk = 196 ± 28). Cows were subjected to 1 of 3 treatments: i) 50 mL saline solution intrauterine infusion (S; n = 23); ii) 2% PVP-I (n = 42); or iii) 150 mg of amoxicillin trihydrate and 40 mg/mL gentamicin sulphate (n = 32). All cows followed the progesterone-based fixed-time insemination protocol. Data were analyzed by Chi-square test and 1-way analysis of variance. The PVP-I treatment (n = 25; 59.5%) was as effective as the AB treatment (n = 19; 59.4%), compared to the S treatment (n = 5; 21.7%) to achieve a new conception. The cows in group PVP-I conceived in a shorter time than those in group AB (46.0 ± 8.7 days versus 105.0 ± 10.0 days; P < 0.05) with a more efficient insemination to conception ratio (2.32 ± 0.43 versus 4.10 ± 0.32; P < 0.05). Data suggest that intrauterine PVP-I administration is superior to intrauterine AB administration in rescheduling reproductive protocol upon late embryonic and fetal losses.  相似文献   
246.
In this study, it was aimed to perform an energy analysis of organic grape production in Besni district of Ad?yaman province of Turkey. In order to determine the energy input-output of organic grape production, the observations and surveys were performed in the 82 organic grape growers in Ad?yaman province. 82 farms were selected on full count method. The data obtained from study were collected from 82 different farms (398.32 hectares) by face to face questionnaires and observations. In organic grape farms, energy input-output analysis was also determinated by observation and survey methods in production season in 2015. In organic grape production, energy input was calculated as 24,875.06?MJ?ha?1 and energy output was calculated as 163,430?MJ?ha?1. Energy use efficiency, energy productivity, specific energy and net energy in organic grape production were calculated as 6.57; 0.56?kg?MJ?1, 1.79?MJ?kg?1 and 138,554.94?MJ?ha?1, respectively.  相似文献   
247.
The goal of this study is to do the energy input-output analysis of organic mulberry. This study was conducted at the organic mulberry producing facilities during the 2015–2016 production seasons in Adiyaman-Tut region of Turkey. The agricultural input energies and output energies used in organic mulberry production were computed to determine the energy input-output analysis. According to the research findings, the energy inputs in organic mulberry production were computed respectively as 3948?MJ ha?1 (59.01%) drip and sprinkler irrigation energy, 1092.42?MJ ha?1 (16.33%) gravity irrigation energy, 449.33?MJ ha?1 (6.72%) diesel fuel energy, 416.52?MJ ha?1 (6.23%) farmyard manure energy, 335.14?MJ ha?1 (5.01%) human labour energy, 253.52?MJ ha?1 (3.79%) machinery energy, 93.12?MJ ha?1 (1.39%) transportation energy, 75.78 MJ ha?1 (1.13%) animal labour energy and 26.62?MJ ha?1 (0.40%) organic fertilizer energy. Total input energy was computed as 6690.46?MJ ha?1. Production output organic mulberry yield were calculated as 37,627.84?MJ ha?1. The energy output/input ratio, specific energy, energy productivity and net energy computations were computed respectively as 5.62, 1.51?MJ kg?1, 0.66?kg MJ?1 and 30,937.37?MJ ha?1. The consumed total energy input in organic mulberry production could be classified as 88.20% direct, 11.80% indirect, 88.10% renewable and 11.90% non-renewable.  相似文献   
248.
Sainfoin (Onobrychis viciifolia Scop.) is one of the most drought-tolerant perennial legumes that can thrive in dry, alkaline soils. A 3-year study in the Central Anatolian Region of Turkey compared the persistence, productivity and nutritive value of sainfoin planted with nurse crops, namely Hungarian vetch (Vicia pannonica Crantz.) or triticale (× Triticosecale Wittm, ex A. Camus), at three seeding rates. Sainfoin and nurse crop emergence were significantly affected by the companion nurse crop, sowing rate and establishment year. The number of sainfoin plants at emergence was lower during a drier “bad” year (110 plant/m2) than in a “good” precipitation year (236 plant/m2). Triticale had a more negative impact on sainfoin growth than vetch. Planting nurse crops at high seeding rates (90 kg/ha) reduced the number of sainfoin seedlings as compared to the control, while the low seeding rate had little impact on sainfoin emergence. Planting sainfoin with triticale resulted in much greater yield exceeding 10 t/ha, but reduced the forage nutritive value compared to sainfoin monocultures and sainfoin–vetch mixtures. The seeding rate of the nurse crops during a dry year did not affect DM yield in the year of establishment nor in the following year. The findings of this study indicate that planting sainfoin with a nurse crop can substantially increase the DM yield in the year of establishment without yield penalties in the subsequent years, despite fewer established plants, as compared to sainfoin monocultures.  相似文献   
249.
This paper describes advances in hatchery and grow‐out technology of cobia (Rachycentron canadum, Linnaeus). In 2007, methods for capture, transport, acclimation, sampling, conditioned spawning, larval rearing, fingerling production, nursery, shipping and grow‐out have been perfected. Survival rates ranging from 17.5% to 35% were achieved from egg to shipping size fingerlings (1.0 g) in 2007 at the University of Miami Experimental Fish Hatchery, with production of approximately 20 000 fingerlings per 12 000 L tank. Wild and F1 broodstock cobia have been conditioned to spawn through temperature manipulation producing viable eggs for experimental and production level larval rearing trials in several hatcheries. Brood fish have also been induced to spawn using hormones. Cobia appear to be susceptible to infestations by parasitic protozoa such as Amyloodinium ocellatum and to infections caused by deleterious bacteria such as Photobacterium spp. and Vibrio spp. Prophylactic methods used to prevent and control epizootic diseases at the hatchery are summarized. Improved techniques for cage management were implemented, and both novel designs of submerged cages deployed in exposed areas and traditional gravity cages in protected areas have been used for commercial ongrowing of cobia in the Americas and the Caribbean region.  相似文献   
250.
The objectives of this study were to identify, at species level, thermophilic campylobacters isolated from clinically healthy sheep by a multiplex polymerase chain reaction (mPCR). The heterogeneity among Campylobacter jejuni and C. coli isolates was also investigated using a restriction fragment length polymorphism (RFLP) analysis of the flagellin (flaA) gene. Samples of intestinal contents, gall bladders and faeces were collected from 610 healthy sheep. While gall bladder samples were plated directly onto Preston agar, an enrichment stage was applied for intestinal and faecal samples. Of the 610 samples, 302 (49.5%) were positive for Campylobacter spp. Using a mPCR assay for species identification, 103 (34.1%) were positive with C. jejuni-specific primers, while 100 (33.1%) were positive with C. coli-specific primers. Additionally, 16 (11.9%) of the intestinal content samples were positive for both species by mPCR. All the isolates identified as C. jejuni and C. coli were successfully subtyped by flaA typing. Of 203 isolates tested, 48 different flaA types were found. Twenty-six flaA types were identified among C. jejuni isolates and the remaining 22 from C. coli isolates.  相似文献   
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