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21.
The relationship between the severity of natural freezing and frost damage (FFD) and the observed growth recovery and field production of Superior potatoes (Solanum tuberosum L.) was investigated under screen house conditions. Potato plants were damaged by accidental freezing and frost during the early phase of shoot growth, 40 days after planting in highland summer crop areas in Korea. The observations of FFD were classified visually into “severe” (>75%), “moderate” (50%), “mild” (<25%), and “no FFD”, based on the percentage of the area of the shoots which was damaged. The early vegetative growth recovery, in terms of groundcover, was reduced as the level of FFD increased. At 28 days after a freezing and frost damage (DAFF), the potato plants with mild or no symptoms had produced more groundcover than the plants with moderate or severe symptoms. At 35 DAFF, groundcover was the same across all levels of severity, at nearly 100%. Despite the slower canopy development, plants with FFD achieved a higher fresh shoot weight and total chlorophyll content, whereas physiological growth indices such as photosynthetic rate and stomatal conductance of leaves were not different among levels of FFD at 60 DAFF. The number of lateral stems and days to tuberization increased significantly as the level of FFD increased; however, the harvest index, the number of tubers per plant, and seed tuber production were all reduced in plants with severe FFD. In addition, the tubers from plants with severe FFD had an increased ratio of length to width and 40% more tuber eyes than tubers from undamaged plants. The elongated tubers also showed an increase in cell division, demonstrated by higher numbers of cells in the cortical zones. The aforementioned measurements were obtained from natural event and led to a deduction that Superior has a capacity to recover from FFD, unless the plants were severely damaged (>75%) early in the season.  相似文献   
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In this study, nonwoven fabrics were developed for the replacement of polyurethane foams in car interiors, in particular, cushioning materials for car seats. Polyethylene terephthalate (PET) hollow fibers and two types of bicomponent binder fibers were used to manufacture automotive nonwovens by carding processes and then post-bonding processes, such as needle punching or thermal bonding. The physical and mechanical properties of nonwovens were thoroughly investigated with respect to the effects of binder fibers and bonding processes. The tensile strength and elongation for nonwovens were found to be significantly improved by combined needle punching and thermal bonding processes. In addition, the nonwoven cushioning materials were characterized in terms of hardness, support factors, and compressive and ball rebound resilience. The nonwovens showed greater hardness than the flexible PU foam. However, support factors over 2.8 for the nonwovens indicated improved seating comfort, along with better seating characteristics of greater resilience and air permeability in comparison with the PU foam.  相似文献   
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 洋麻炭疽病早在1912年即于台湾发現,以后传到內地,按其引种的来源分析,是自印度传入中国的。  相似文献   
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Birch (Betula pendula Roth) growth within the Western Siberia forest-steppe was analyzed based on long-term (1897–2006) inventory data (height, diameter at breast height [dbh], and stand volume). Analysis of biometry parameters showed increased growth at the beginning of twenty-first century compared to similar stands (stands age = 40–60 years) at the end of nineteenth century. Mean height, dbh, and stem volume increased from 14 to 20 m, from 16 to 22 cm, and from ~63 to ~220 m3/ha, respectively. Significant correlations were found between the stands mean height, dbh, and volume on the one hand, and vegetation period length (rs = 0.71 to 0.74), atmospheric CO2 concentration (rs = 0.71 to 0.76), and drought index (Standardized Precipitation-Evapotranspiration Index, rs = ?0.33 to ?0.51) on the other hand. The results obtained have revealed apparent climate-induced impacts (e.g. increase of vegetation period length and birch habitat drying due to drought increase) on the stands growth. Along with this, a high correlation of birch biometric parameters and [CO2] in ambient air indicated an effect of CO2 fertilization. Meanwhile, further drought increase may switch birch stand growth into decline and greater mortality as has already been observed within the Trans-Baikal forest-steppe ecotone.  相似文献   
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A series of experiments was carried out in 2012–2014 in Pailin province, Cambodia, to determine the potential and agronomic requirements for a dry season sunflower crop. The research showed that the six high-oleic sunflower hybrids evaluated were similar for phenological development and yield but two varieties had <50% emergence and poor hybrid seed quality was seen as a constraint to planting under rainfed conditions. Sunflower receiving a basal application of 20:20:15 (N:P2O5:K2O) at 200 kg ha?1 produced achene yield of 2423 kg?1, while side-dressing with urea had no effect on yield. Application of s-metolachlor post-sowing pre-emergence was the most effective weed control treatment and significantly increased sunflower achene yield. Post-emergence weed control was not adequate to prevent yield loss from weed competition. The study showed that sunflower can be grown successfully as a dry season crop in North-West Cambodia when planted no-tillage on residual soil water remaining after maize harvest in October and November. The critical requirements for success are related to preservation and effective use of residual soil water and include minimal soil disturbance, adequate application of fertiliser at sowing, and pre-emergence control of weeds, especially grasses.  相似文献   
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The effect of instant cooked rice made from giant embryo mutant or ordinary normal rice on the glucose metabolism and antioxidative defense system in mice under a high‐fat (HF) diet condition was investigated. The animals were randomly divided and given experimental diets for seven weeks: normal control diet, HF diet, and HF diet supplemented with instant normal white, normal brown, giant embryonic white, or giant embryonic brown rice. At the end of the experimental period, the HF mice showed a marked increase in the blood glucose level, insulin concentration, and plasma and erythrocyte lipid peroxidation and a significant decrease in the glycogen level relative to the control group. However, diet supplementation with instant cooked giant embryonic and normal brown rice counteracted this high‐fat‐induced hyperglycemia and oxidative stress through regulation of the glucose‐regulating and antioxidant enzyme activities. The giant embryonic brown rice was the most effective in improving the glucose metabolism and antioxidant defense status in mice under the HF diet condition. The results demonstrate that the giant embryo rice mutant may be useful in the development of instant cooked rice with strong hypoglycemic and antioxidative properties.  相似文献   
30.
In a herd of 70 bull calves (4-5 months of age) kept on pasture, 56 (80%) animals showed, after natural infection with Moraxella bovis (M. bovis), typical clinical signs of infectious bovine keratoconjunctivitis (IBK). Eyes with epiphora, photophobia, blepharospasm and/or a corneal ulcer with a diameter of less than 5 mm were considered as moderately affected. Those with a corneal ulcer > 5 mm diameter and/or even more profound findings were considered as severely affected. The objective was to study in IBK affected calves in a prospective randomized case control study the therapeutic efficacy of intrapalpebral (i.p.) injections of oxytetracycline (OTC) (200 mg OTC-hydrochloride 10% in the upper eyelid of moderately affected and in both eyelids of severely affected eyes) and intramuscular (i.m.) treatment (long-acting OTC-dihydrate; 20 mg/kg body weight for both moderately and severely affected patients). 29 animals (20 moderately affected, 9 severely affected) were treated i.p. and 27 animals (19 moderately, 8 severely affected) were treated i.m.. For fly control, deltamethrin was applied to all bulls at d 0. The OTC-treatment was repeated at intervals of 3 - 8 d until recovery. All animals recovered within 42 days.The mean number of treatments per animal and the interval between diagnosis and assessment of healing were not affected by the method of OTC administration; the latter averaged out at about 10 d for moderately affected and 17 d for severely affected eyes. Significantly less medication was required per animal for i.p. than for i.m. treatments (moderately affected: 281 vs. 2033 mg; severely affected: 1156 vs. 3982 mg). In conclusion, both methods of OTC administration were found to be similarly effective for the treatment of IBK in calves.  相似文献   
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