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A literature review is presented on past and present experienceswith chemical flower and fruit thinning of apple and pear, amplifiedwith some data of recent trials with known and new flower thinners(mainly ethephon and ammonium thiosulphate) and fruit thinners (mainly1-napthylacetic acid (NAA), its amide (NAAm), carbaryl, ethephon,conjugates of NAA and NAAm and benzyladenine). Chemical-thinningpractices give quite unpredictable results. This inconsistency is atleast partly caused by weather factors, such as temperature and airhumidity, but tree factors are also involved. To solve this problem,climate-room and multi-site trials are proposed, together with anintergrated approach in elucidating background mechanisms and thedevelopment of new fruit thinning compounds.

A simple and rapid phosphorimetric method for the determination of α-naphthaleneacetamide residues in fruit samples is presented. The method is based on a new, simple and sensitive methodology: Heavy Atom Induced Room Temperature Phosphorescence (HAI-RTP). The effect of different heavy atom salts and sodium sulfite concentration over the phosphorescence signals was investigated. The resultant HAI-RTP spectra were successfully applied for determining α-naphthaleneacetamide concentrations in the range of 7.8 to 100 μg·L−1, with relative standard deviations between 2.6 and 5.7%.

Terbacil applied to whole-spur 'Delicious' apple (Malus domestica Borkh.) trees reduced photosynthesis and fruit set. The addition of the surfactant X-77 to terbacil sprays increased fruit thinning and leaf injury. Terbacil sprays applied to leaves only (fruit covered with foil) were as effective as when applied to leaves plus fruit. Dipping fruit alone in a terbacil solution did not cause abscission. Shading trees for 4 days with 92% polypropylene shade material reduced fruit set =50%. Spraying trees with carbaryl reduced fruit set by 25%. The combination of shade + carbaryl spraying reduced fruit set by 89%. Chemical names used: l-naphthalenyl methylcarbamate (carbaryl); 3-tert- butyl-5-chloro-6 -methyluracil (terbacil); 2-chloroethylphosphonic acid (ethephon); alkaryl polyoxyethylene al- cohols (X-77). Spur 'Delicious' apple trees may be thinned with terbacil, carbaryl, ethephon, Vydate, naphthaleneacetic acid (NAA), or naphthaleneacetamide (NAD). Sprays of NAD (50 mg·liter -1 ) or NAA (10 mg·liter -1 + surfactant) typically increase the number of "pigmy" fruit (abnormally small fruit) of spur 'De- licious' types, particularly at rates needed to cause thinning (Byers, 1978; Rogers and Thompson, 1969; Rogers and Wil- liams, 1977; Unrath, 1978). Combinations of carbaryl plus NAA

Trials were conducted on 11-year-old trees of ‘McIntosh’ apple (Malus domestica, Borkh.) in Creston, British Columbia, to analyse the thinning effects of the blossom spray sodium 4,6-dinitro-ortho-cresylate (DNOC), and single and combination treatments of the post-bloom sprays naphthalene acetic acid (NAA), naphthaleneacetamide (NAD), and 1-naphthyl-(N-)methyl carbamate (carbaryl). DNOC was ineffective as a thinning agent when used alone. NAA did not significantly affect numbers of remaining fruit when used alone or with NAD or carbaryl. NAD showed significant thinning effects when applied alone or with carbaryl. Carbaryl was an effective thinning agent when used alone. The effects of carbaryl alone and carbaryl with NAD were found to persist after spacing the fruit on the branches by hand.

Trials on chemical fruitlet thinning in apple cultivar ‘Gala’ were carried out during the growing seasons of 1985/86 and 1986/87 using the thinning agents naphthaleneacetic acid (NAA), naphthaleneacetamide (NAAm) and carbaryl in single and combined sprays, adding either a nonionic wetting agent (WA) or an emulsifiable mineral oil (MO) as an adjuvant. NAA was applied on three application dates (5, 10 and 15 days after full bloom (AFB)). The recommendation of the best treatments was based on economic analyses. NAA at 15 mg l−1 plus WA applied at 5 days AFB resulted in effective thinning in both growing seasons. Later applications at 15 days AFB provided insufficient thinning. The use of NAA at reduced concentration with MO as an adjuvant gave about the same thinning effect as NAA at double concentration with WA as an adjuvant at 10 or 15 days AFB. With both spray additives, the improvement of mean fruit weight by NAA decreased with later application. The NAA-MO combination, applied at 5 days AFB, resulted in about the same mean fruit weight as the NAA-WA combination, although fruit load density was notably higher with the first combination. NAAm at 50 mg l−1 plus WA provided a similar reduction of fruit load density and improvement of mean fruit weight as NAAm at 30 mg l−1 plus MO during 1985/86. The application of NAA followed by a later spray of carbaryl, using reduced concentrations of both chemicals and adding MO, provided adequate thinning and increased partial profit in comparison with hand-thinning. All chemical treatments were economically equal or superior to hand-thinning. The most profitable treatments for commercial use are listed.

Como a repicagem de mudas de figueira (Ficus carica L. cv. Roxo de Valinhas) apresen ta frequentemente problemas no transplante, estudou-se o efeito de produtos químicos nesta fase crftica para a formação do figueiral. Procedeu-se aos tratamentos de redução da área foliar, pulverização com Transplantone 10 g/l água, Oed green (oxietileno docosanol) 40 ml/1 ,Good-rite peps (polisulfeto de polietíleno) 0,6 ml/l e Mobileaf 200 ml/l, além do controle. Redução da área foliar ou pulverização com oxietileno docasonol aumentaram a porcentagem de sobrevivência das figueiras transplantadas. Os produtos químicos não promoveram variações significativas na altura das mudas de figueira 'Roxo de Valinhos'. Auxinas componentes do Transplantone (naftalenacetamida e àcido naftalenacético) causaram aumento no número de folhas da figueira transplantada. This research deals with the effects of chemicals on, transplantation of Ficus carica L. cv. Roxo de Valinhos. Fig plants were sprayed with Transplantone (naphthaleneacetamide plusnaphtaleneacetic acid) 10 g/1 , Oed green (oxyethylene docosanol) 40 ml/1, Good-rite peps (polyethylene polysulfite) 0,6 ml/1, and Mobileaf 200 ml/1. A check treatment and aereduction to half of leaf area were also established. Reduction of leaf area and application of oxyethylene docosanol promoted higher plant survival. The chemicals did not affect the growth of transplanted plants. Auxins constituents of Transplantone increased leaf number of fig plants.

Spraying potato plants with dilute concentrations of a-naphthal-eneacetamide was not effective in increasing flower or seed ball production in the greenhouse at Beltsville Maryland, or Greeley, Colorado. Higher concentrations reduced flower production at Presque Isle, Maine.

The activity of indoleacetic, indolebutyric, naphthaleneacetic, dichlorophenoxyacetic, and naphthoxyacetic acids and certain derivatives has been tested on deseeded Avena coleoptiles. Intact as well as the usual decapitated coleoptiles were employed, and both agar and lanolin blocks (and lanolin in unilateral smears) were used as carriers. 1. When tested in agar on decapitated coleoptiles, potassium salts of indoleacetic, indolebutyric, and naphthaleneacetic are as active as the free acids. Esters of indolebutyric are of about the same activity as the acid; esters of indoleacetic are less active than the corresponding acid; and esters of naphthaleneacetic acid are inactive. Indoleacetamide, naphthaleneacetamide, and dichlorophenoxyacetic acid are but slightly active. Naphthoxyacetic, its ethyl ester, and naphthoxypropionic acids are completely inactive (although reported by others to be active in the tomato test). 2. When applied in agar to intact coleoptiles, indoleacetic, indolebutyric, and naphthalenea...

1. 1. A localized epidemic of sleeping sickness is described with details of the measures taken to control it and to prevent its spread. 2. 2. Special reference to the control of G. palpalis is made, with notes of various experiments carried out. The use of screens in various types of clearings is commented on. 3. 3. The epidemiology of the disease, with special reference to the disease incidence and the fly incidence in the locality, is discussed. A household, or “family,” incidence of the disease is recorded. 4. 4. The treatment of the cases is detailed, with reference to the high relapse rate in first stage cases.

Penetration of naphthaleneacetic acid through enzymatically isolated upper pear (Pyrus communis L. cv. Bartlett) leaf cuticle increased as the donor pH was decreased. Naphthaleneacetamide penetration was not influenced by donor pH. The effect of pH on naphthaleneacetic acid penetration was reversible. Higher receiver (simulated leaf interior) pH favored penetration of naphthaleneacetic acid. Changes in the degree of dissociation, and hence polarity, as controlled by hydrogen ion concentration was the prime factor in the response of naphthaleneacetic acid to pH. At pH values lower than the pK (4.2 for naphthaleneacetic acid), the molecule was primarily undissociated, lipophilic, and penetrated into the cuticle; whereas, at pH values above the pK naphthaleneacetic acid was ionized, hydrophilic, and penetrated the cuticle with difficulty or not at all. Data presented are consistent with the hypothesis that naphthaleneacetic acid and naphthaleneacetamide penetration through the cuticle takes place by diffusion.

Alexander, Aaron D. (Walter Reed Army Institute of Research, Washington, D.C.), Herbert G. Stoenner, Garnett E. Wood, and Robert J. Byrne . A new pathogenic Leptospira , not readily cultivated. J. Bacteriol. 83: 754–760. 1962.—A pathogenic Leptospira was isolated from water of the Grand River, (S.D.) that differed significantly from other known leptospirae in that it could not be cultivated in conventional leptospiral media. Growth was promoted in Fletcher's medium modified to contain 20% rabbit serum. The isolate, after several serial passages, was lethal for hamsters. It could not be adapted to grow in the chick embryo. Guinea pigs and calves inoculated with the isolate developed febrile and antibody responses but showed no other overt signs of disease. The strain was identified on the basis of cross-agglutination and agglutinin-adsorption tests as a new subserotype of Leptospira naam and was therefore designated as L. naam , subserotype dakotii .