9个葡萄柚品种与曼赛龙柚嫁接生理酶活性研究

以云南本地曼赛龙柚Citrus maxima cv.Mansailong为砧木,取引进的9个葡萄柚C.paradisi Macf.品种为接芽,采用带木质部"T"形芽接法嫁接,研究了接穗和砧木枝条愈伤组织及嫁接后接口愈伤组织过氧化物酶(POD)、超氧化物歧化酶(SOD)、多酚氧化酶(PPO)和过氧化氢酶(CAT)活性的变化规律。结果表明,在曼赛龙柚上,火焰、亨路比、瑞路比和里德马叙等4个葡萄柚嫁接愈合最好,矮化和哈路比愈合最差,POD、SOD和CAT三种酶的活性与葡萄柚嫁接愈合密切相关,且其活性差异程度可以作为葡萄柚嫁接亲和性的预测酶,PPO活性与嫁接亲和性间无明显规律。

Effect of Protective Cultivation Patterns of Rice in Cold Areas on Soil Physiological and Biochemical Status in Paddy Field

[Objective] The research aimed to explore how to use the soil reasonably,prevent the degradation of soil fertility,maintain soil fertility,improve the ecological environment of paddy field and improve the soil productivity of paddy field from the cultivation aspect.[Method] Taking kenjiandao 10 as the material,the variation laws of root weight,soil physical and chemical characteristics,soil enzyme,straw decomposition rate,soil temperature,microorganism of rice under the planting patterns of water-saving pro...

Effects of Water Deficit and Increased Nitrogen Application in the Late Growth Stage on Physiological Characters of Anti-aging of Leaves in Different Hybrid Rice Varieties

[Objective] This study aimed to explore the effects of water and fertilizer regulation on the function of leaves in the filling stage. [Method] Six hybrid rice vari- eties including prematurely aged types and non-prematurely aged ones were selected as experimental materials. Limiting water treatment （with soil water potential of about -25 kpa） and increasing nitrogen treatment （additional 10% of granular nitrogen fertiliz- er in addition to limiting water treatment） were applied after heading to analyse the rates of aging and physiological responses of anti-aging in different hybrid rice vari- eties under water deficit and increased nitrogen conditions taking regular water and fertilizer as control. [Result] The results showed that water deficit accelerated the leaf senescence, and prematurely aged types-＇Zhongyou838＇, ＇Tianyou998＇ and ＇Long- ping601 ＇-were more markedly affected by water deficit, of which the rates of chloro- phyll degradation were 6%-8% higher compared to that in another three hybrids. In- creasing nitrogen treatment raised chlorophyll content and slowed down its degrada- tion. Water deficit caused the increase of abscisic acid （ABA） content to obviously varying degrees in leaves of six hybried rice varieties. Responses of ABA content in six hybried rice varieties to increased nitrogen fertilizer were not consistent. Except in ＇Zhongyou838＇, ABA content in the other five hybrids had varying degrees of in- crease. The responses of the activity of antioxidant enzymes in different hybried rice varieties were inconsistent. In response to increased nitrogen fertilizer in combination with water deficit, the activity of each antioxidant enzyme changed differently. Water deficit enhanced the accumulation of malondialdehyde （MDA） in leaves of each hybrid rice. The correlation analysis showed that chlorophyll content was extremely signifi- cantly positively correlated to the resistance of each antioxidant enzyme; SOD activity in leaves also positively related to ABA content. [Conclusion] The rate of leaf aging, physiological activity of anti-aging, and response to water deficit varied in different hy- bried rice varieties. The activity of antioxidant enzymes were not all induced to improve by ABA. SOD activity can be an indicator of resistance to stress. Increasing nitrogen ap- plication significantly postponed leave senescence in the late growth stage of rice.

Epidermal collagenase activity and its induction by 20-hydroxyecdysone in the fiddler crab Uca pugilator

The epidermal collagenase activity and its induction by 20-hydroxyecdysone in Uca pugilator were investigated. Zymographic electrophoresis showed four bands of collagenase activity, 16, 19, 22 and 29 kDa in molecular weight, with the former two accounting for 60% and 36% , respectively, of the total collagenase activity. The collagenase activity varies during the molting cycle. Among the molt stages tested, Premolt Stage Do exhibited the highest epidermal collagenase activity for both the 16 and 19 kDa isoenzymes and, as the molt stage proceeded, the enzymatic activity of these two isoenzymes decreased, with the lowest activity for both found in Premolt Stage D3 -4 - Injection of 20-hydroxyecdysone significantly induced the activity of the 16 kDa eollagenase in the epidermis of Uca pugilator, suggesting that the activity of this isoenzyme is under molting hormone control. Although 20-hydroxyeedysone injection did not result in a statistically significant increase in the activity of the 19 kDa isoenzyme, a tendency of the induction was nonetheless demonstrated. This is the first report on epidermal collagenase activity and its induction by the molting hormone in a crustacean .

Myocardial enzyme activities of black bears and comparison with those of human beings

According to the principle of enzyme reaction rate, healthy pent black bears’ myocardial enzyme activity is assayed by visual colorimetry and compared with that of healthy human beings. The determination at 37 °C and the statistic analysis of the experimental data work out the following findings. For male black bears, the average CK activity is 163.20 U/L, the confidence interval of its expected value (127.70 to 198.70) U/L, and the coefficient of variation 39.2%; the average CK-MB activity 21.62 U/L, the confidential interval (17.72 to 25.51) U/L, and the coefficient of variation 34.26%; the average LDH activity 604.20 U/L, the confidence interval (524.56 to 683.83) U/L, and the coefficient of variation 23.80%; the average HBDH activity 516.70 U/L, the confidence interval (453.06 to 580.34) U/L, and the coefficient of variation 22.24%; the average GOT activity 69.70 U/L, the confidence interval (60.21 to 79.19) U/L, and the coefficient of variation 24.59%. For female black bears, the average CK activity is 145.50 U/L, the confidence interval (114.59 to 176.21) U/L, and the coefficient of variation 38.27%; the average CK-MB activity 18.84 U/L, the confidence interval (14.64 to 23.04) U/L, and the coefficient of variation 40.34%; the average LDH activity 563.70 U/L, the confidence interval (473.80 to 652.60) U/L, and the coefficient of variation 28.80%; the average of HBDH activity 475.50 U/L, the confidence interval (412.10 to 538.40) U/L, and the coefficient of variation 24.07%; the average of GOT activity is 62.37 U/L, the confidential interval (52.54 to 72.20) U/L, and the coefficient of variation 28.46%. The male black bear’s average myocardium enzyme activities are slightly higher than those of the female. But the statistical results indicate that the difference is not significant.

Physiological responses of Chinese longsnout catfish to water temperature

We evaluated the effect of water temperature on the growth and physiology of the Chinese longsnout catfish （Leiocassis longirostris Günther）. The fish were reared at four temperatures （20, 25, 30, and 35℃） and sampled on days 7, 20, and 30. We measured plasma levels of insulin, free thyroxine （FT4）, free 3,5,3＇-triiodothyronine （FT3）, lysozyme and leukocyte phagocytic activity. The optimum water temperature for growth was 27.7℃. The plasma levels of insulin and FT4 declined significantly （P〈0.05） on day 30 at temperatures above 20℃. Lysozyme activity was significantly （P〈0.05） lower at 25℃ than at other temperatures. We conclude that final weight, insulin, FT4, and lysozyme were significantly affected by water temperature.

Effects of Elevated CO_2 and Drought on Plant Physiology, Soil Carbon and Soil Enzyme Activities

Global climate models have indicated high probability of drought occurrences in the coming future decades due to the impacts of climate change caused by a mass release of CO2. Thus, climate change regarding elevated ambient CO2 and drought may consequently affect the growth of crops. In this study, plant physiology, soil carbon, and soil enzyme activities were measured to investigate the impacts of elevated C02 and drought stress on a Stagn[c Anthrosol planted with soybean （Glycine ma,z）. Treatments of two CO2 levels, three soil moisture levels, and two soil cover types were established. The results indicated that elevated CO2 and drought stress significantly affected plant physiology. The inhibition of plant physiology by drought stress was mediated via prompted photosynthesis and water use efficiency under elevated CO2 conditions. Elevated CO2 resulted in a longer retention time of dissolved organic carbon （DOC） in soil, probably by improving the soil water effectiveness for organic decomposition and mineralization. Drought stress significantly decreased C：N ratio and microbial biomass carbon （MBC）, but the interactive effects of drought stress and CO2 on them were not significant. Elevated CO2 induced an increase in invertase and catalase activities through stimulated plant root exudation. These results suggested that drought stress had significant negative impacts on plant physiology, soil carbon, and soil enzyme activities, whereas elevated CO2 and plant physiological feedbacks indirectly ameliorated these impacts.

Growth, Cadmium Accumulation and Physiology of Marigold (Tagetes erecta L.) as Affected by Arbuscular Mycorrhizal Fungi

A pot experiment was carried out to study the effects of three arbuscular mycorrhizal fungi （AMF）, including Glomus intraradices, Glomus constrictum and Glomus mosseae, on the growth, root colonization and Cd accumulation of marigold （Tagetes erecta L.） at Cd addition levels of 0, 5 and 50 mg kg-1 in soil. The physiological characteristics, such as chlorophyll content, soluble sugar content, soluble protein content and antioxidant enzyme activity, of Tagetes erecta L. were also investigated. The symbiotic relationship between the marigold plant and arbuscular mycorrhizal fungi was well established under Cd stress. The symbiotic relationship was reflected by the better physiobiochemical parameters of the marigold plants inoculated with the three AMF isolates where the colonization rates in the roots were between 34.3% and 88.8%. Compared with the non-inoculated marigold plants, the shoot and root biomass of the inoculated marigold plants increased by 15.2%- 47.5% and 47.8%-130.1%, respectively, and the Cd concentration and accumulation decreased. The chlorophyll and soluble sugar contents in the mycorrhizal marigold plants increased with Cd addition, indicating that AMF inoculation helped the marigold plants to grow by resisting Cd stress. The antioxidant enzymes reacted differently with the three AMF under Cd stress. For plants inoculated with G. constrictum and G. mosseae, the activities of superoxide dismutase （SOD） and catalase （CAT） increased with increasing Cd addition, but peroxidase （POD） activity decreased with increasing Cd addition. For plants inoculated with G. intraradices, three of the antioxidant enzyme activities were significantly decreased at high levels of Cd addition. Overall, the activities of the three antioxidant enzymes in the plants inoculated with AMF were higher than those of the plants without AMF inoculation under Cd stress. Our results support the view that antioxidant enzymes have a great influence on the biomass of plants, and AMF can improve the capability of reactive oxygen species （ROS） scavenging and reduce Cd concentration in plants to alleviate Tagetes erecta L. from Cd stress.

Effect of Antimony on Physiological Responses of Green Chinese Cabbage and Enzyme Activities of Allitic Udic Ferrisols

High concentrations of antimony(Sb) in soils and vegetables can cause potential health risk. However, the effect of Sb on the growth and response of crops are not well known and to date, there is still no Sb limit standard for Allitic Udic Ferrisols in China. In this study, a greenhouse experiment was carried out to investigate the effect of antimony(Sb) on biomass, physiological performances,and macro- and micronutrient element concentrations of green Chinese cabbage(Brassica chinensis L.), as well as enzyme activities,in Allitic Udic Ferrisols from Hunan Province, China. Antimony was supplied at rates of 0(control), 2, 5, 10, 20, and 50 mg kg-1and thus with the background value of 1.0 mg kg-1, the Sb concentrations in the treated soil samples were 1, 3, 6, 11 21, and 51 mg kg-1, respectively. The results showed the leaf biomass and ascorbic acid content of cabbage significantly(P < 0.05) decreased by 30.6% and 48.3%, respectively, and soil urease and dehydrogenase activities also significantly(P < 0.05) decreased by 33.6%and 32.5%, respectively, when soil Sb concentration was 21 mg kg-1as compared with the control. The uptake of essential nutrient elements such as Mg, Cu, and Zn by cabbage was obviously affected, while the leaf soluble sugar content slightly changed when the soil Sb concentration exceeded 21 mg kg-1. Based on cabbage physiological responses and soil enzyme activities, the permissible concentration of 21 mg kg-1for Sb in Allitic Udic Ferrisols should be recommended.