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1.
A field experiment was conducted to find out the critical physiological stages of irrigation schedules inducing better growth, physiological efficiency and seed yield potential of berseem ( Trifolium alexandrinum L., Var. S-99-1). For this purpose eight irrigation treatments were made comprised of four treatments of three irrigation (W1, W2, W3 and W4), three treatments of four irrigation (W5, W7 and W8) and one treatment of five irrigation (W6) at various physiological stages i. e. regeneration, flower initiation, full bloom, seed initiation and advance seed development stage.
Thus based on the experimental results the physiological role of watering in berseem seed production could be discussed as:
With-holding of irrigation either at regeneration or at full bloom stage developed potential water stress in plants as indicated by high proline content of irrigation treatments — W4, W1 and W7; and further brought out disturbance on the formation of carotene, synthesis of water soluble sugar and translocation of sugar towards reproductive organs during grain development stage. These stresses adversely affected the plant growth and flowering behaviour. The irrigation at seed initiation stage increased the seed yield. Continuous irrigation did not appear to be useful. Thus it can be concluded that irrigation at three critical physiological stages i. e. regeneration, full bloom and seed initiation was found to be essential for obtaining potential seed yield of berseem.  相似文献   
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创新是一个民族进步的灵魂,是国家兴旺发达的不竭动力源泉。因此,对创新人才的培养,应该从基础教育抓起。为了在语文教学中培养学生的“创新精神”,教师首先应转变观念,使自己成为有创新精神的人。其次为学生创设和谐、民主的学习氛围,让学生最大限度地发展创造性思维能力。应让学生丰富知识、夯实基础、拓展视野,为创新思维的发展打下坚实的基础。  相似文献   
4.
AZD3783, a cationic amphiphilic drug and a potent inhibitor of the 5-hydroxytryptamine (5-HT1B) receptor, was explored as a potential treatment for depression. To support clinical trials, repeat dose toxicity studies in rats and dogs were conducted. Here we report toxicity findings in dogs after dosing from 1 to 3 months. In the 1-month study, there were minimal neuronal vacuolation in the brain, a marked increase in liver enzymes accompanied by hepatocellular degeneration/necrosis and phospholipidosis (PLD), and PLD/cholecystitis in the gallbladder of animals dosed at 47 mg/kg/day. In the 3-month study, neurotoxicity resulted in euthanasia of one animal dosed at 30 mg/kg/day after 86 days. Extensive pathologic changes were seen in all animals in retina epithelium (inclusion bodies), brain (neuronal vacuolation, degeneration, or necrosis and nerve fiber degeneration), spinal ganglia (vacuolation, degeneration, or necrosis), as well as sciatic and optic nerves (degeneration). Pigment-laden macrophages were observed in the lung, kidney, liver, gallbladder, bone marrow, gastrointestinal tract, and lymphoid tissues. Also seen were vitrel and retinal hemorrhage in the eyes. A brain concentration and pathology study showed that the concentration of AZD3783 in the brain was approximately 4 times higher than in the plasma after 4 weeks of dosing, however, they were similar in all regions examined, and did not correlate with areas with pathologic findings. Our findings with AZD3783 in dogs have not been reported previously with other CNS compounds that effect through serotonergic pharmacology.  相似文献   
5.
在我国,高等教育由“精英教育”进入国际公认的“大众化教育”时期的背景下,如何保证教学质量,是摆在高等教育管理工作者面前的重要课题。我们结合学校实际开展“评教三结合”,在加强教学管理,推进名师工程方面进行了探索与实践。  相似文献   
6.
In the Bay of Saint-Brieuc, a 3,110-ha tidal bay in NW France, English Channel, the cockle Cerastoderma edule has been collected by traditional fishing methods for many decades without any evaluation or management of this resource taking place. Since 2001, the National Natural Reserve of the bay of Saint-Brieuc has carried out an evaluation of the stock and a mapping of the cockle fishing grounds each year. Analysis of the spatial structure of the population is approached by cartography through interpolation of the data using the kriging method. The recruitment zones are geographically quite well defined and located in areas limited to the mean-tide zone. The distribution of the population was affected by passive displacement of juvenile cockles. Evaluation using the matrix of individual numbers for each age group found the inter-annual mortality rates to be about 60%. Somatic production was estimated and expressed in ash-free dry weight. The average annual production ranged from 7.4 to 14.5 g/m2. In the autumn of 2006, the minimum legal fishing size changed from 30 to 27 mm (corresponding to individuals aged about 2.5 years). The model developed shows that this change has led to a doubling of the fishable stock.  相似文献   
7.
The distribution and abundance of overwintering Calanus finmarchicus in the Faroe–Shetland Channel was studied during December 1994 and January 1995. Maximum abundance of animals in the Channel was approximately 50 000 m−2, with a peak concentration of 627 m−3 at a depth of 930 m. Copepodite stages IV and V accounted for > 98% of the population. A clear association was found between the horizontal and vertical distribution of animals and the Arctic water masses in the bottom of the Faroe–Shetland Channel. The Wyville–Thomson Ridge formed a barrier to the southern distribution of Arctic waters and the abundance of overwintering C. finmarchicus was 25 times lower to the south of the Ridge than to the north. Spatial variability in lipid content and composition indicated that overwintering C. finmarchicus in the southern Norwegian Sea were in poorer condition with respect to wax ester content, and in a more advanced state of emergence from overwintering, than the animals within the Channel. The overwintering stock in the Channel probably originated from the Norwegian Sea or from north of the Faroe Islands. The Faroe–Shetland Channel is an important source of animals advected into the northern North Sea in the spring (March/April). The population abundance in the Faroe–Shetland Channel was estimated to be 4.5 × 1014 individuals, which is more than adequate to account for the mean concentration of adult stages observed in the northern North Sea in April.  相似文献   
8.
In this study, an effort was made to cure the pigment deficiency syndrome (PDS) exhibited by pond‐reared Fenneropenaeus indicus (H.Milne Edwards) broodstock, using the blue‐green algae Spirulina as a carotenoid source in diet. The PDS symptoms included bleaching of ovary and reduced early larval performance. Biochemical analysis indicated reduced quantity of total carotenoids in egg and nauplii from the females with PDS. When PDS females were fed 30 g kg?1Spirulina‐supplemented diet immediately after the appearance of symptoms, the egg and nauplii carotenoid values improved gradually and attained the pre‐PDS values after a minimum of 4 week period. Spirulina supplementation also improved significantly (P < 0.05) the spawn quality (hatch per spawn, nauplii per spawn, nauplii viability) and larval quality indices (P < 0.05). The egg and nauplii protein values exhibited a trend similar to carotenoids, confirming the influence of latter on protein stability previously reported by researchers. The study confirms the bioavailability of carotenoids from Spirulina to shrimp broodstock and recommends its regular inclusion in diet to preclude carotenoid deficiency‐related problems in shrimp hatcheries.  相似文献   
9.
The stress response of grass carp to salinity was evaluated assessing the levels of hematocrit, leucocrit, plasma glucose, sodium, potassium and calcium. Mean hematocrit values increased following exposure to salinity. Mean leucocrit values elevated after exposure to salinity for 24 h, then decreased. Mean plasma glucose increased during saline exposure for 48 h and then decreased to normal values. Plasma sodium and chloride levels were increased to their highest values after 48 h. While plasma potassium value increased with the exposure time, plasma calcium values were not affected by salinity exposure.  相似文献   
10.
Cultured red porgy Pagrus pagrus (L.) males (n=6) were sampled every 2 weeks for milt, in order to monitor changes in sperm quality parameters during a whole spawning period. On 11 January 2001, 60% of the fish were spermiating, increasing to 100% in mid‐February and dropping to 30% by mid‐April. Sperm density showed a slight increasing trend, with mean values ranging between 8.6 and 23.7×109 spermatozoa mL?1. Sperm motility percentage exhibited a significant improvement during the spawning season (analysis of variance (anova ) P=0.0001). The duration of forward motility for the major part of the monitoring period ranged between 2 and 4 min. Red porgy spermatozoa maintained their viability for many days after whole storage of milt at 4°C. During the monitoring period there were significant changes in the mean duration of sperm survival after cold storage, ranging from 5 to 12 days. The total volume of expressible milt was maximal on 28 March, increasing from a mean value of 1.7 mL to 5.3 mL kg?1. Milt production of captive‐reared red porgy does not appear to be limiting, when compared with the volume of expressible milt produced by other cultured marine fishes.  相似文献   
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