半致死的

The results showed that with temperature decreased, levels of endogenous hormone changed obviously,such as the increase of the content of Abscisic acid,and the decrease of Gibberellic acid.

结果表明，低温半致死温度降低的同时，脱落酸含量上升，赤霉素含量下降，尤其值得引起关注的是脱落酸含量与赤霉素含量的比值的变化表现出与低温半致死温度更密切的关系(R =- 0 992 0 )。

The result showed that the best is Coreopsis drummondii, its semi-lethal concentration and limit concentration both reached as high as 1.4%; The next was Callistephus chinensis, its semi-lethal concentration was 0.6%, and its limit concentration was 1.2%; The middle was Althaea rosea, its semi-lethal concentration was 0.4%, and its limit concentration was 1.2%; The lower one was Rudbeckia hirta, its semi-lethal concentration was 0.4%, and its limit concentration was 1.0%.

结果表明：耐盐性最强的是金鸡菊，其耐盐半致死浓度和耐盐极限浓度高达1.4%；其次为翠菊，耐盐半致死浓度为0.6%，耐盐极限浓度为1.2%；耐盐力中等的是蜀葵，其耐盐半致死浓度为0.4%，耐盐极限浓度为1.2%；耐盐性最差的是黑心菊，耐盐半致死浓度为0.4%，耐盐极限浓度为1.0%。

The effect of formalin in seawater on P.epinepheli was that the semi-lethal concentration is 250×10-6 for 25 min,and 50×10-6 for 50 min.

海水福尔马林对拟合盘虫的作用表现为：25 min处理的半致死浓度为250×10-6，50 min处理的半致死浓度为50×10-6。

The ability of cold resistance of almond was analyzed by the formulation of LT50, the investigation of over-wintering, the measurement of water content in dormant period and the analysis of anatomical structure in the annual branches of two introduced varieties. The results showed: the LT50 of Fritz, Nonpareil and CK was -24.88℃,-20.56℃ and -17.15℃, respectively; the index of chilling injury of these varieties was 10%, 45% and 87%, respectively; and the classification of cold resistance was in turn high resisting, moderate resisting and easily shoot-shriveling.

通过对两个引种扁桃扶兹和那普瑞尔1年生枝条的半致死温度(KT50)拟合、越冬调查、休眠期的含水率及其解刨结构的分析，对扁桃的抗寒力进行了研究，结果表明：Fritz、Nonpareil及CK1年生休眠枝的半致死温度(LT50)分别为-24.88℃、-20.56℃和-17.15℃；冻害指数分别为10%、45%和87%，抗冻害评级依次为高抗、中抗、易抽。

That is to say,the cold resistance of these trees had raised by exercise in winter. The difference of the semilethal temperature of the trees at the beginning of Sept.2003 was slight(-5.03～-6.08℃).

试验结果表明，12 月底采样树种的半致死温度低于9 月初采样树种的半致死温度，即经过冬季一段时间的低温锻炼，植株的抗寒性有所增强。

That is to say, the cold resistance of these trees were close.But the difference of the semilethal temperature of the trees in the end of Dec.2003 was remarkable(-9.86～-13.48℃). The difference of the cold resistance of different tree species raised by exer-cise in winter.

月初采样树种的半致死温度相差不大(-5.03～-6.08℃)，即未经低温锻炼时，6个树种的抗寒能力相近；而12 月底采样树种的半致死温度相差较大(-9.86～-13.48℃)，即经低温锻炼后，6 个树种的抗寒性差距增大。

When EMS was applied, it was found that 2.0% EMS resulted the highest microkernel rate (15.6‰). Treating the materials with 2.0% EMS for 4 hours could lead to semi-lethal. Cytological observations found that chromosome aberration phenomena such as single microkernel, double microkernel, three microkernel, chromosome bridge, resort chromosome and syncytium were presented in the mutants.

EMS诱变途径中，浓度为2.0 %处理时间为4 h的组合获得最高的微核率（15.6‰），EMS浓度为2.0 %处理时间为4 h的组合使材料达到半致死；细胞学的观察看到了单微核、双微核、三微核、染色体桥、滞留染色体和合胞体等染色体畸变现象，再生苗中发现了1棵变异株。60Co辐射的诱变途径中，20Gy的剂量使不定芽半致死，再生苗中发现了1棵变异株。

Polyhedrin and virion, which were isolated and purified from Agrotis setegum nuclear polyhedrosis virus, are administered to 3-instar Heliothis armigera larvae with Heliothis armigera nuclear polyhedrosis virus. Both polyhedrin and virion could increase mortality of H. armigera larvae, shorten half mortality time and decrease half mortality concentration.

对黄地老虎核型多角体病毒的多角体蛋白和病毒粒子组分进行分离纯化，分别与棉铃虫核型多角体病毒混合感染三龄棉铃虫幼虫，发现此二种组分均能够提高棉铃虫幼虫的死亡率，缩短半致死时间，降低半致死浓度。

There are experimental results as follows:(1) Eriophorum comosum Nees shows strong cold resistance in plasmalemma permeability research. The lethal temperature of Eriophorum comosum Nees is the lowest LT_(50 in comparison with another two plants and is lower than -11.5℃ in August 2005 and December 2005; Soluble protein content of each plant is rising before or after cold hardiness. By SDS-PAGE, Protein band is analysed. Band quantity of Eriophorum comosum Nees is the most and its band color is darkest.(2) Soluble sugar content of three plants after cold hardiness are higher than before cold hardiness, moreover soluble sugar content after cold hardiness shows a decline and there is a narrow range in Eriophorum comosum Nees; Free Proline accumulation is changed by cold stress, and cold resistance is relative to free Proline accumulation; chlorophyll content of both three plants, including chlorophyll a, chlorophyll b and chlorophyll a/b, show a decline tendency along with the descent of temperature. Cynodon dactylon is highly sensitive to cold stress.(3) The soil POD and urease activities' absolute value of Erioophorum comosum Nees and Pogonatherum panideumHack were more than that of Cynodon dactylon before or after low temperature stress, especially POD activities.

实验结果表明：(1)在膜透性的研究中，丛毛羊胡子草抗寒性最强，采用电导率法测得半致死温度LT_(50最低，丛毛羊胡子草抗寒锻炼前后半致死温度LT_(50均小于-11.5℃；在可溶性蛋白含量研究中，抗寒锻炼前后三种植物的可溶性蛋白含量均增加，同时采用SDS-PAGE法，通过对蛋白条带分析，以丛毛羊胡子草条带数最多且着色深；(2)在可溶性糖的研究中，三种植物经抗寒锻炼后叶片可溶性糖含量都比抗寒锻炼前高，且经过抗寒锻炼后三种植物可溶性糖均呈下降趋势，丛毛羊胡子草可溶性糖含量下降较小；从游离脯氨酸含量可知，低温的胁迫影响了植物叶片游离脯氨酸的含量变化，植物的抗寒性与游离脯氨酸有关；低温胁迫下三种植物叶绿素含量随着温度的下降，叶绿素含量、叶绿素a、叶绿素b和叶绿素a／b均呈下降趋势，狗牙根对低温胁迫最为敏感；(3)低温锻炼前后，丛毛羊胡子草和金发草的土壤过氧化物酶与脲酶活性的绝对值均大于狗牙根的，特别是过氧化物酶，说明丛毛羊胡子草和金发草的酶活性大于狗牙根的。

Mmol/L to juvenile Japanese sea bass, and 75.86, 63.46, 56.42 mmol/L to black rockfish. When pH is steady at 8.40 + 0.10, the 24-, 48-, 96-hour LC50 of Alk are 72. 79, 65. 28, 57. 92 mmol/L to Japanese sea bass, and 69. 47, 59. 37, 51. 96mmol/L to black rockfish. It is obvious that the toxicity of Alk to fish increases with the progressive increase of Alk or time when pH is at a constant level.3. According to analysis of variance of orthogonal test, pH and Alk have signification effects on the mortality rate of black rockfish.

pH在正常养殖范围时，通过碱度对海水鱼类鲈鱼、黑鲪的急性毒性试验，得到pH=8.10±0.10时，碱度对鲈鱼稚鱼(体长1.6～2.2cm)24、48、96h的半致死值为60.88、44.36、36.06mmol／L，安全浓度为7.07mmol／L；pH=8.05±0.10时，碱度对黑鲳幼鱼24、48、96h的半致死值为75.86、63.46、56.42mmol／L，安全浓度为13.32mmol／L.pH=8.40±0.10时，碱度对鲈鱼幼鱼24、48、96小时的半致死值为72.79、65.28、57.92mmol／L，安全浓度为15.76mmol／L；对黑鲪幼鱼24、48、96h的半致死值为69.47、59.37、51.96mmol／L，安全浓度13.01mmol／L。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。