THE SYSTEMIC INSECTICIDAL ACTION OF CERTAIN COMPOUNDS OF FLUORINE AND OF PHOSPHORUS ON PHAEDON COCHLEARIAE FAB.

Four compounds— bis dimethylaminophosphonous anhydride (schradan), bis (dimethylamino)fluorophosphine oxide ( dimefox ), diethyl paranitrophenyl phosphate ( paraoxon ) and sodium fluoroacetate ( acetate )—have been tested against the mustard beetle, Phaedon cochleariae Fab. When the four compounds are compared by a direct contact technique in which insects can also imbibe some of the test solutions, or the insects are caged with foliage which has been dipped and then dried, the order of toxicity to adults and larvae was found to be Paraoxon > acetate ≏ dimefox > schradan.
The paraoxon is very much more toxic than the other compounds. In all cases the adults are more resistant than the larvae.
When the insecticides are applied systemically the order of toxicity changes to Paraoxon > dimefox > acetate ≏ schradan because the acetate causes the plants to wilt and less of it is absorbed. Both paraoxon and dimefox give complete kills of adult Phaedon which is the most resistant stage, at practical concentrations.
When the insecticides were applied to the outer leaves and translocated to the inner untreated leaves an effect was observed with the dimefox and paraoxon after numerous application, but with a single application very inconsistent results were obtained.
It is concluded that schradan and the acetate are ineffective systemically against Phaedon. The dimefox and paraoxon are very effective, but because of their high mammalian toxicity they would require very careful handling in practice.     

THE SYSTEMIC INSECTICIDAL ACTION OF SODIUM FLUOROACETATE AND OF THREE PHOSPHORUS COMPOUNDS ON THE EGGS AND LARVAE OF PIERIS BRASSICAE L.

Four compounds, bis dimethylaminophosphonous anhydride ( anhydride ), bis (dimethylamino)fluorophosphine oxide ( oxide ), diethyl paranitrophenyl phosphate ( E 600) and sodium fluoroacetate ( acetate ), previously shown to have systemic insecticidal activity against aphids, have now been tested against the eggs and larvae of Pieris brassicae L.
The anhydride proved to have very little toxic action on Pieris , but the other three compounds showed both contact toxicity and systemic insecticidal action when taken up by the roots of cabbage plants from solution and from soil. The acetate, but more especially the E600, also showed systemic action following application to the leaves.
In all cases the order of decreasing toxicity was E600 > acetate > oxide > anhydride. E600 is the only compound which is outstandingly toxic to Pieris eggs and larvae. It has the added interest that when watered on to the roots of cabbage plants it kills larvae in egg batches on the leaves. Death takes place at the stage when the larvae are biting through the shells. The oxide and acetate proved to be surprisingly innocuous.
Unless it is felt to be too poisonous E600 is worthy of consideration as an insecticide against Pieris eggs and larvae, since it is highly effective as a contact insecticide and also has some systemic action.     

印楝素、印楝和苦楝种子抽提物在盆栽植物中的内吸作用(英文)

本文报道具有拒食活性和生长发育调节作用的植物性杀虫剂印楝素、印楝和苦楝种子抽提物的内吸防治几种农业害虫的试验研究。结果表明：内吸施用印楝素或印楝种子粗提物（1mg和2．5mg／盆）能明显降低烟草天蛾幼虫的正常生长和干扰马铃薯甲虫的生长发育;用≥25mg／盆的印楝素和印楝种子租提物能明显控制麦二叉蚜的种群繁殖。而苦楝种子甲醇抽提物对上述三种害虫的内吸控制种群繁殖作用不明显。     

SYSTEMIC INSECTICIDAL ACTION OF AZADIRACHTIN, NEEM SEED AND CHINABERRY SEED EXTRACTS APPLIED AS SOIL DRENCHES TO POTTED PLANTS

Abstract  The systemic insecticidal activities of: 1) azadirachtin, a potent insect antifeedant and growth regulator isolated from seeds of the neem tree, Azadirachta indica , 2) a neem seed extract containing 0. 30 quantitative fraction of azadirachtin, and 3) a methanolic extract of seeds from the chinaberry tree, Melia azedarach , a close relative of neem were determined. Soil drenches of azadirachtin or the neem seed extract at 1 and 2. 5 mg to potted potato ( Solanum tuberosum ) and tomato ( Lycopersicon esculentum ), remarkably retarded the growth of Manduca sexta larvae and strongly disrupted the pupation of Leptinotarsa decemlineata larvae, respectively. However, five to ten times as much azadirachtin or neem seed extract was needed to reduce the amount of tomato and potato foliage consumed. On sorghum ( Surghum biocolor ), much higher quantity (≥25 mg) of azadirachtin or the neem seed extract was necessary to slow the population growth of Schizaphis graminum , and prolong the survival of treated plants. But methanolic extracts of chinaberry seeds ( M. azedarach ) from two sources (Guangdong, PRC and Hurricane, Utah, USA) at 150 mg per pot were ineffective in reducing aphid population growth and preventing plant damage.     

昆虫病原线虫与其他杀虫因子之间相互作用的研究进展

昆虫病原线虫作为生物杀虫剂近年来已被人们所认识,并已广泛应用于防治多种农林害虫.本文介绍了昆虫病原线虫与其他杀虫因子之间相互作用的研究概况.     

SEROLOGICAL STUDIES IN BAPTISIA AND CERTAIN OTHER GENERA OF THE LEGUMINOSAE

Fourteen species of Baptisia were compared serologically, using antiserum against B. nuttalliana. By means of both immunoelectrophoretic and double-diffusion techniques, it was possible to disclose 11 distinct arcs plus some weaker arcs, with few reliable (definite and repeatable) differences detected among the species of Baptisia investigated. Since the individual species of Baptisia are often quite distinctive, as judged by other chemical and morphological criteria, the serological data are in this instance conservative and appear to be effective in circumscribing the genus. In contrast, striking interspecific differences in the serological properties of unicellular green algae have been obtained (reported elsewhere) by similar techniques in this laboratory. It is concluded that serological data should be regarded as adjuncts to other systematic knowledge only on the basis of empirical manifestations of their utility. There is no clear justification for regarding serological data as intrinsically either superior or inferior to other systematic criteria.     

MASS CULTURE OF ALGAE FOR FOOD AND OTHER ORGANIC COMPOUNDS

Krauss, Robert W. (U. Maryland, College Park.) Mass culture of algae for food and other organic compounds. Amer. Jour. Bot. 49(4): 425–435. Illus. 1962.—Data are being collected which appear to support the use of unicellular algae for human food. Analyses of proteins, fats, carbohydrates, and vitamins indicate that unicellular green algae, especially Chlorella, should be excellent sources of these nutrients. The effectiveness of the algae for the support of growth of chickens, mice, rats, and rabbits has been found to be good. However, only limited studies have been done with humans. The problem of acceptability varies with the nationality of the subjects and the preparation of the food. Serious gaps still exist both in the technology of production and in the experimentation required to establish nutritional value. Nutrition studies using algae free of bacteria are urgently needed.     

ULTRASTRUCTURE OF THE SHOOT APEX OF CHENOPODIUM ALBUM AND CERTAIN OTHER SEED PLANTS

The ultrastructure of cells of the vegetative shoot apices is described for Chenopodium album, Kalanchoë blossfeldiana and K. laxiflora, Bryophyllum daigremontianum, Nicotiana rustica, and N. tabacum (Maryland Mammoth), and Ginkgo biloba. A less intensive study was made of the last three listed. The structures and organelles usually associated with meristematic cells were observed: dictyosomes, plastids (in various stages of development), mitochondria, endoplasmic reticulum (ER), vacuoles, lipid droplets, and plasmalemma. In addition, spherosome-like structures were observed in all zones of the shoot apices. Also, multivesicular bodies were observed in C. album and B. daigremontianum. Ribosome density is greater in cells of the flank meristem. Proplastids, plastids with prolamellar bodies, or grana have a differential distribution in the apex, characteristic for a particular species. Confirmation could not be given to the concept that vacuoles arise as a series of local dilations in long extensions of the so called "smooth ER." The tonoplast and ER are distinguishable at the time of inception of a vacuole, although the tonoplast may arise from the ER. Rapid growth of a vacuole and/or fusion with other vacuoles may result in irregularly shaped prevacuoles. No vacuoles were observed to originate from cisternae of dictyosomes in the species studied.     

THE ELECTRICAL IMPEDANCE OF MUSCLE DURING THE ACTION OF NARCOTICS AND OTHER AGENTS

1. The effect of certain inorganic cations upon the electrical impedance of the sartorius muscle of the frog was investigated. While Na, K, and Mg have little effect upon the resistance of muscle, Ba and Ca cause it to fall. The use of physiologically "unbalanced" salt solution does not in itself seem to affect muscle impedance. 2. The time course of the effect upon muscle impedance of the penetration of substances into the intercellular spaces was studied by treating the muscle with sugar solutions. Half of the effect is over in three-quarters of a minute when the sugar solution is permitted to circulate past both sides of the muscle. This sets an upper limit for the time necessary for inorganic cations and organic narcotics to reach the cell surfaces. The action of inorganic cations and organic narcotics upon muscle is slow compared to the time necessary for them to reach the scene of action. The penetration of the sugar solutions into the intercellular spaces of muscle was found to follow the well known diffusion law, the amount diffusing in being proportional to the square root of the time. Average values of 77.7 per cent for ρ, the volume concentration of fibers; 231 ohms specific resistance for r ₂, the resistance of the interior of the fibers; and 71.0° for θ, the phase angle of the impedance locus, were obtained for the muscle in Ringer''s solution. How these values change when the muscle is placed in various concentrations of sugar was also studied. 3. The action of a number of organic narcotics upon muscle was studied. All decrease 1000 cycle resistance if the concentration is sufficiently high. A detailed analysis of the action of the narcotic, iso-amyl carbamate, was made, and it was noted that low concentrations increase resistance while higher concentrations decrease it. By investigating the effect of narcotics upon muscle impedance over a wide frequency range, it was found that during narcosis the resistance of the fiber membranes first increases and then decreases, and, if the drug is present in sufficiently great concentration, membrane resistance may completely disappear. Membrane capacity is only very slightly affected.