豇豆锈病菌生命表和繁殖表

把豇豆单孢锈菌（Ｕｒｏｍｙｃｅｓｐｈａｓｅｏｌｉｖａｒ．ｖｉｇｎａｅ））侵染豇豆（Ｖｉｇｎａｓｅｓｑｕｉｐｄａｌｉｓ）的整个夏孢子世代区分为孢子、芽管、附着胞、气孔下泡囊、菌丝、定殖和孢子堆等七个阶段。在自然条件下，利用豇豆单孢锈菌侵染豇豆幼苗叶片世代发育过程的试验结果，编制了其生命表和繁殖表，计算结果表明：其最大相对增长率ｒｍａｘ＝０．６８（天－１），平均世代时间Ｔｇ＝１．３１（天），净殖率Ｒｏ＝７０９７（个）。本文还根据真菌生活史有别于昆虫这一事实，通过修改Ｍｏｒｒｉｓ－Ｗａｔ模型，初步描述了一种计算真菌种群趋势指数的方法。

Life Tables for the Experimental Population Phenacoccus solenopsis Tinsley at Different Temperatures

[Objective] The study was to investigate the effect of temperature on pop- ulation dynamics of Phenacoccus solenopsis Tinsley, so as to providing references for the control and prevention of this pest. [Method] The experimental populations were kept in laboratory and fed on cotton plants, and the major parameters of the population were recorded. [Result] By the construction of age specific life tables and reproductive life tables for the P. solenopsis experimental population at 24, 27, 30 ~C, more than 10 parameters were obtained, including mean generation time, survival rates of different stages and sexes, life expectancy, spawning period, fecundity amount per female, sexual ratio, net reproductive rate, intrinsic increase rate, finite increase rate, population trend index, curve of survival rate, and curve of daily fe- male oviposition, which revealed the effect of temperature on growth and develop- ment, life expectancy and fecundities of P. solenopsis. [Conclusion] The reproductive potential of the P. solenopsis population is very great at suitable temperature, making it easy to outbreak. The research provided scientific basis for population dynam- ics investigation, predication and integrated control of P. solenopsis.

The Four-Seasonal Movement of Life

The four-seasonal movement is the general movement of the universe. Galaxies, living beings, society, man-made worlds and all substances have or take part in the four-seasonal movement. There are transverse four-seasonal movement and longitudinal four-seasonal movement. The former is the breathing movement. All substances have the function of breathing. Breathing involves living beings, celestial bodies, society and man-made systems and living beings of different levels have different ways of breathing. The longitudinal four-seasonal movement of living beings is controlled by genes. The four-seasonal movement is confined. Life originates in seeds and seeds are generated in the four-seasonal movement. Thoughts, ideas, designs and methods are the seeds of celestial bodies, society and man-made worlds. Just like living beings, galaxies, and society also have reproductive function. Reproduction has three major means： self-generation, generation by augmentation and generation by transformation. The reproduction of living beings is self-generation while the reproduction of the solar system and other galaxies is generation by augmentation. Man-made objects, society and galaxies are formed with automatic organization of thoughts, thus called generation by transformation. The solar system and the earth have reproduction function. Living beings began with the combined action of the earth, the solar system and the universe. Life forms of the universe include dominant life and recessive life. Different forms of life transform continuously.

Nuclear Transition Between the Conjunction Cells of Phaeodactylum tricornutum Bohlin (Bacillariophyta)

Phaeodactylum tricornutum is one of the important marine diatoms for oceanic primary production. Its reproduction has profound significance in the life cycle; however, the nuclear behavior during its sexual reproduction was not clear. In this study, we observed the nuclear transition and determined its correlation with cell conjunction. It was found that two cells jointed at their apices first and swung and aligned each other immediately, and nucleus from one cell was able to transfer into another one during cell conjugation. The cell pairs conjugated for nuclear transition were different from those formed in mitosis in hypovalve thickness and cellular arrangement. Our findings proved the existence of sexual reproduction in P. tricornutum.

Life History of the Lenkoran Capoeta Capoeta Gracilis （Keyserling, 1981） in the Atrak River, Northern Iran

Within the wide distribution of Lenkoran in Iran, populations of the species inhabit variety of habitats. The authors hypothesized that each river may contribute to habitat-specific variation in life history of the fish. To test this, a total of 378 specimens of Capoeta capoeta gracilis caught in the Atrak river （northern Iran） from Dec. 2007 to Nov. 2008 were examined for life history attributes. The population has a 5-year life cycle. Weight-length relationship （WLR） was estimated as W = 0.0127TL28981 for males, W = 0.0083TL3998 for females and W = 0.0084TL3942 for the population, being allometric negative for males and positive for females and the population. The VBGF fit to back-calculated size at age data were： Lt = 22.11 （1-e-0.19（t＋135））, Lt = 25.37 （1-e-0.18（t＋125）） and Lt = 24.92 （1-e-018（1＋122）） for males, females and sexes combined respectively. Sex ratio was significant from the parity, females dominated. The reproductive season, evaluated from GSI, extended from Apr. to July, with the highest peak in May for males and in Apr. for females. The absolute fecundity ranged between 458-5,743 eggs with a mean of 1,375.06 eggs. Fecundity relative to total weight fluctuated from 14.90 to 132.58, with a mean value of 48.79 eggs·g-1. The diameter of oocytes ranged from 0.53 to 2.40 mm with a mean value of 1.46. The life history patterns of C. c. gracilis in the considered population imply that the many population characteristics of this species in the river differ markedly from those of other rivers of its range distribution in northern Iran. Probably, respond to environmental characteristics to improve fitness locally is the more suitable choice for differentiated life history strategies of the species in the river.

Development and reproduction of ‘B＇ biotype Bemisia tabaci （Gennadius） （Homoptera： Aleyrodidae） on four ornamentals

Effects of four commercial ornamentals on the development, survivorship and reproduction of the whitefly B biotype Bemisia tabaci (Gennadius) were studied in the laboratory (temperature 26 ±1℃; relative humidity 75%-90%; L: D 14:10). The total survivorship from egg to adult on hibiscus (Hibiscus rosa-sinensis L.), poinsettia (Euphorbia pulcherrima Will), cottonrose hibiscus (Hibiscus mutabilis L.) and variegated leafcroton (Codiaeum variegatum ‘Aucubaefolium') were 33.69%, 40.55%, 79.11%, and 29.39%,respectively. The developmental periods from egg to adult varied from 23.12 days on cottonrose hibiscus to 32.13 days on hibiscus. The average longevity of adult females ranged from 6.87 days on variegated leafcroton to 21.07 days on poinsettia. The average numbers of eggs laid per female were 9.20, 25.13, 54.45, and 26.79 on the above respective hosts. The intrinsic rates of natural increase (rm) for B biotype B. tabaci on cottonrose hibiscus was the highest. Based on life table analyses of whitefly populations, cottonrose hibiscus was the most suitable host for B biotype B. tabaci in this study.