植物生长调节物质对果实生长发育的调控

本文就赤霉素、细胞分裂素、乙烯利对果实生长发育的调控作用进行了较为系统的论述,并对其在果树上的利用方法、时期、浓度等作了说明。     

PHOTOCONTROL OF GROWTH AND FLOWERING OF CARYOPTERIS

Piringer , A. A., R. J. Downs , and H. A. Borthwick . (U. S. Dept. of Agriculture, ARS, Belts ville, Md.) Photocontrol of growth and flowering of Caryopteris . Amer. Jour. Bot. 50(1): 86–90. Illus. 1963.—Flower buds were initiated on plants of Caryopteris × clandonensis A. Simmonds (C. incana [Houtt.] Miq. × C. mongholica Bunge) on all photopcriods but developed to anthesis only when daily dark periods exceeded 8 hr. Anthesis occurred in not less than 22 days after the beginning of 11 or more short photoperiods. Treatments with short days could be interrupted by as many as 30 non-inductive long days without significant increase in the minimum number of short days required for anthesis. Anthesis, like floral initiation of many plants, was reversibly controlled by red and far-red radiation acting through phytochrome. The inductive effectiveness of long dark periods was nullified by 1 min of red light or about 1 hr of far red. It was modified by night temperature in the range 45–70.F and filament lengths of stamens were shorter at night temperatures of 60 than at 70 F.     

THE EFFECT OF AGITATION AND TURBULENCE OF THE GROWTH MEDIUM ON THE GROWTH AND VIABILITY OF MICROCYSTIS

SUMMARY

Observation of natural blooms of Microcystis, suggested that increased turbulence plays a role in retarding bloom formation of Microcystis. In laboratory experiments the influence of turbulence mediated by a magnetic stirrer on the growth and viability of Microcystis in batch cultures was determined. The different turbulences (0, 25, 75, 126, 209 and 314 cm sec^?1 linear velocity) had no effect on the growth rate. There was a highly significant correlation between the linear velocity and percentage viability as determined by a plating and serial dilution method. The viability ranged from 0,8% for stationary cultures to 99,2% for vigorously stirred (314 cm sec^?1 linear velocity) cultures.     

大麻哈鱼的年龄与生长

通过对2010和2011年采捕到乌苏里江大麻哈鱼洄游群体571个样本的鳞片观察和基础生物学测定,研究了大麻哈鱼的年龄判定和生长模拟。大麻哈鱼鳞片属于典型圆鳞,有明显的年轮特征,为一年一个周期,年轮特征表现为疏密型。部分鳞片有明显幼轮,幼轮和年轮根据鳞径大小能够区分。采集样本的雌雄组都分为2+,3+,4+三个年龄组,也都以3+龄组数量最多。采用特殊Von Bertalanffy、Logistic、Gompertz和幂指数生长方程分别模拟了大麻哈鱼1—4龄间的生长,通过最大似然法估计各模型的参数。采用残差平方和(Analysis of the residual sum of squares,ARSS)分析得出大麻哈鱼雌雄个体间生长无显著差异(P>0.05),故将雌雄个体放一起进行生长模拟。AIC和BIC检验结果显示特殊VBGF方程为最适生长模型,公式为:Lt=90.04×[1 e 0.3(ti+0.27)]。大麻哈鱼的生长速度随着年龄增长逐年降低,且性成熟年龄小的个体生长速度大于性成熟年龄大的个体。应对大麻哈鱼年龄与生长进行长期监测,为增殖放流等渔业资源管理措施提供基础资料。     

THE LIGHT GROWTH RESPONSE AND THE GROWTH SYSTEM OF PHYCOMYCES

1. The Roscoe-Bunsen law holds for the light growth response of Phycomyces if the time component of stimulation is short. With exposures longer than a few seconds, the reaction time to light is determined by the intensity and not by the energy of the flash. 2. The possible nature of the very long latency in the response to light is considered in terms of the structure of the cell and its mechanism of growth. It is suggested that during the latency some substance produced by light in the protoplasm is transported centrifugally to the cell wall or outermost layer of protoplasm. 3. The total elongation occurring over a period of 1 to 2 hours is independent of flashes of light or temporary darkening. Light acts by facilitating some change already under way in the growth system, and during the principal phase of elongation is not a necessary or limiting factor for growth. 4. Judged by the reaction time, the original sensitivity is restored in the light system following exposure to light in about one-third the time required for equilibrium to be reattained in the growth system.     

EGF对大鼠卵巢颗粒细胞增殖与分化影响的研究

许多研究发现,表皮生长因子(EGF)对生殖功能有重要的调节作用。本文用体外细胞培养的方法,研究了EGF对大鼠卵巢颗粒细胞增殖与分化的影响及其作用方式。结果如下:EGF可以明显抑制颗粒细胞DNA的合成,但促进孕酮的生成,后者是因为EGF能显著提高细胞内3β-羟甾脱氨酶(3β-HSD)的活性。放射受体分析表明,颗粒细胞上存在EGF的特异性受体,其K_d为1.83±0.3×10~(-8)mol/L,B_(max)为1.75±0.29×10~4个位点/细胞。卵巢免疫组化结果未发现颗粒细胞有EGF样免疫染色,而卵泡膜、黄体及间质内等均有阳性染色。以上结果提示,EGF可能通过旁分泌机制作用于颗粒细胞的EGF受体,从而调节细胞的生长和性激素的分泌,这对于颗粒细胞的成熟及卵泡的发育有着重要意义。     

鱼类生长和生长激素分泌活动的调节（综述）

本文综述近十年来在鱼类生长激素分泌和鱼体生长的神经内分泌调节方面取得的研究进展,阐明脑（各种神经内分泌因子）－脑垂体（分泌生长激素）－肝脏（产生类胰岛素生长因子）轴调控鱼类生长的作用,并在此理论基础上提出可供养鱼生产实践应用的基本途径。     

GROWTH AND DIFFERENTIATION OF NEUROSPORA HYPHAE

Zalokar , Marko . (Yale U., New Haven, Conn.) Growth and differentiation of Neurospora hyphae. Amer. Jour. Bot. 46(8): 602–610. Illus. 1959.—Neurospora hyphae grow only at their tips. New protoplasm is formed throughout the hyphae and transported to the tips by active cytoplasmic streaming. This enables the fungus to grow at a prodigious rate. The use of radioactive precursors demonstrated that the rate of protein and ribonucleic acid formation does not decrease substantially in hyphal regions distant from the growing point. Apical growth of hyphae results in a morphological differentiation into young regions filled with cytoplasm and dense with nuclei and old regions, vacuolated and laden with fat droplets. Cytochemical methods were used to study the biochemical differentiation of hyphae and attention was focused on the growing region. It was found that hyphal tips, i.e., the first 50–100 μ of the growing end of the hypha, differed substantially from the rest of the young hyphae. Hyphal tips were slightly richer in proteins and significantly richer in protein-bound sulfhydryl groups and ribonucleic acid. Glycogen was absent at the tips. Peroxidase increased at the tips, while cytochrome oxidase and succinic dehydrogenase decreased. Alkaline phosphatase exhibited strong activity in a short region behind the extreme tip. β-galactosidase, in a few cases, was more active at the tips than in the rest of the hyphae. The results of cytological and cytochemical investigations are discussed in connection with the problem of cellular differentiation.     

玉米根系生长及向水性的模拟

用面向对象的程序设计（ＯＯＰ）技术组建了玉米（Ｚｅａ ｍ ａｙｓ）根系生长的三维模型,并用该模型模拟了根系在不同土壤水分剖面以及有、无向地性响应时的生长过程,探讨了根系向水性产生的机制以及向水性与向地性之间的关系．模型中将根系前沿看作由根尖构成的群体,每个根尖都对其周围环境独自作出响应,其中只有少数能继续分支． 模拟结果显示,玉米根系各单根受局部水势的影响而以不同速率伸长,即可造成总体的向水性． 如果土壤剖面上的水势由下到上递减,由此引起的单根伸长速率的不均匀分布将使整个根系在总体上表现出收拢和一致向下的生长趋势,并导致下层的根量相对增加．根系的向地性虽能使上述趋势增强,但它与向水性的机制是完全不同的     

大型溞生长、生殖和种群增长的研究

年龄6±6小时的纯系大型溞培养在25±1℃静置换水条件下,饲以斜生栅藻,其平均寿命为68.40±9.82天。龄期(x)和年龄(t,天)之间呈曲线迴归关系:t=-2.245+1.510x+0.035x2(r=0.99,p3.86-0.131t)(式中Y为累计生殖量个数,t为天数)。       

双歧杆菌生长和代谢过程的研究

研究了双歧杆菌在两种培养基（牛乳培养基和肉汤培养基）中的生长和代谢的规律,测定了厌氧发酵过程中菌体生长及基质消耗曲线,探索了在发酵过程中流加碱调节ｐＨ值以提高产菌量的途径。