Studies were conducted to determine the amount and distance of outcrossing between fluorescent and nonfluorescent strains of ryegrass. Both experimental spaced-plant conditions and grower seed fields were investigated. There was substantially less crossing among plants grown in seed fields than in plots of spaced plants. Beyond 6 m from the border, outcrossing became negligible between all cultivars tested. Beyond 12 m from the border there was no evidence of crossing.

A comparison of protein profiles of leaves during different stages of shoot and callus induction showed similarities as well as differences in the expression of proteins.  A protein of 39 kDa was expressed in low levels in leaf explants and increased in intensity during induction of shoot organogenesis in both the cultivars. Analysis of protein patterns during organogenesis and callus proliferation from leaves by two dimensional gel analysis revealed the separation of 39 kDa protein into four spots during organogenesis with pI values ranging from 4.2-5.8.  However, the isoforms of 39 kDa protein with pI values of 4.2 and 5.8 were highly expressed in callus of M-5 cultivar in contrast to S-36 cultivar where only one isoform with pI value of 4.2 was detectable. The analysis of protein synthesis in different stages of development in the cultures may acts as markers to differentiate the group of specific isoforms.

Examination of 223 samples of the rumen contents of cattle grazing in an arid zone indicated the contribution to the diet by components of the vegetation. The diet consisted of grass; which was represented by 43 species comprising 85.7 percent; herbage, with 99 species comprising 4.7 percent; and edible trees and shrubs known as "topfeed" with 63 species comprising 9.4 percent. There was 0.2 percent of indeterminata. Results show the importance of perennial grasses and herbage together with palatable trees and shrubs in giving stability to grazing in dry times. Seasonally, annual grasses and herbage provide preferred fodder for comparatively short periods of a month or so. In these flush periods, herbage and topfeed are very little selected. Rumen samples are also an aid in determination of causative plants when poisoning is suspected.

Stomata] aperture has been used by a number of workers as a physiological indicator of plant water status. With apples, early work shows that stomatal aperture may provide a useful and sensitive measure of plant responses to applied water and the onset of stress conditions. Leaf and fruit water potentials of Jonathan, Delicious and Granny Smith apples were measured using a dye method which is described. Compared with a vapour equilibration technique the differences did not exceed ±1 atm. for the 3 varieties tested.

A simple routine procedure for testing frost hardiness of woody species has been worked out, using Pinus silvestris (L.) as the experimental plant. Shoots or twigs are placed in deep-freezes maintained at different temperatures. The rate of cooling of the plant tissues depends on the temperature of the deep-freeze. It is more rapid than the rates usually employed in freezing tests. The merits and disadvantages of this freezing method are discussed. The degree of injury is determined by a modification of the conductivity method. The procedure has been used for determining changes in frost hardiness of Scots pine from October to May. The values obtained are reproducible, and even small changes in degree of hardiness of very hardy plant tissues may be determined by the method.

The destruction of organic matter from widely different soils was evaluated by using hydrogen peroxide and sodium hypochlorite oxidation procedures. The amounts of extractable Si, Mn, Al, and Fe were determined on the residues following treatment with the oxidizing agents by using acid ammonium oxalate and 0.5N NaOH extraction procedures. In addition, the amount of Si, Mn, Fe, and Al in the extracting solutions was determined. It was found that NaOCl extracted more organic matter with less destruction of the oxides than procedures employing H₂O₂. This was substantiated statistically using the t-test as applied to paired values. Three treatments with NaOCl were concluded to be satisfactory for destruction of organic matter with minimum removal of Si, Mn, Fe, and Al.

Em amostras de 134 cafèzais, distribuídos nos principais grupos de solos do Estado de São Paulo, colhidas em três estações do ano, foram determinados 12 elementos químicos essenciais, sódio e alumínio. A percentagem de cafèzais deficientes em nitrogênio foi superior a 80% em todos os solos. No Podzolizado de Lins e Marília, o segundo elemento em falta foi o ferro. No Latossolo Roxo, depois do nitrogênio, a maior deficiência foi a de potássio e zinco; no Podzólico Vermelho Amarelo-Orto, a de boro. | Roughly, coffee fields are distributed on. the main types of soil in the State of São Paulo as follows: Podzolized Soils of Lins and Marilia, 70%; latosolic B "Terra Roxa", 15%; Ortho-Red Yellow Podzol, 10%; other types, 5%. This paper presents and discusses data on foliar analyses of coffee, plants cultivated on the 3 first soil types. It complements a previous survey made on red-yellow ortho podzol. Leaf samples were collected in the spring, summer and fall, from 134 "Mundo Novo" coffee fields. Besides the content of 12 essential elements, amount of Na and Al were also determined in these samples. Fe, Zn, Mn, and Cu were determined by atomic absorption spectrophotometry. The first 3 elements were determined in a wet digest of 0.5 g of dry plant material with a mixture of HNO3-H2SO4-HC10(4), in a final volume of 20 ml. Determination of Cu, on the other hand, required an extract obtained by dissolving in 10 ml of 0.25N HC1, ashes from 1.25 g of dry leaf tissue, incinerated at 500°C for 2 hours. The same extract used for Fe, Zn and Mn analyses served for Na and Al determination. However, content of Al was estimated by colorimetric method of Aluminon (1) whereas amount of Na was determined by flame emission photometry (2). The remaining elements - N, P, K, Ca Mg, S-S0(4), B and Mo - were determined according to the process described by Lott et al (4, 5). Evaluation of the nutritional condition of the coffee fields in each soil type was based upon the amount of the elements present in the leaf tissue sampled in the summer, compared to the levels considered as critical (4). The results of these evaluations showed a high proportion of plants defficient in nitrogen, in all soil types, indicating the importance of nitrogen fertilization. In Podzolized Soils of Lins and Marilia, attention should be given to Fe, Ca and Zn defficiency; there is also the possibility of toxic effects induced by excess of Mn in such soils. Besides N defficiency, latosolic B "Terra Roxa" had frequently defficiency of K and Zn, while Ortho-Red Yellow Podzol, of boron.

ENGLISH: Totals of 59,547 tagged yellowfin and 90,412 tagged skipjack were released during 1952-1964 throughout the range of the fishery in the eastern Pacific Ocean during that period. Most of the fish were released from commercial baitboats, either on regular fishing trips or on chartered trips to catch fish for tagging. There we re 8,397 yellowfin and 4,381 skipjack returned from these releases. There appear to be two main groups of yellowfin in the eastern Pacific Ocean. There is considerable intermingling among the fish of the two groups, however. The fish of the northern group (west coastof Baja California, Gulf of California, and Revillagigedo Islands) first appear in the Revillagigedo Islands in about April, and migrate north along the Baja California coast during the spring and summer and south along that coast during the fall. Recruits to the southern group (Tres Marias Islands to northern Chile) appear at many points or continuously along most of the coast. The fish which first appear in the northern Panama Bight in April migrate rapidly northwest to Central America and Mexico and south to the Gulf of Guayaquil. There also appear to be two main groups of skipjack in the eastern Pacific Ocean. The fish of the northern group (west coast of Baja California, Gulf of California, and Revillagigedo Islands ) perform about the same migration as do the yellowfin of the same area, but most of the skipjack apparently then migrate to the central Pacific Ocean during the fall and/or winter. Recruits to the southern group (Central America to northern Chile) appear mostly in or near the Panama Bight. The fish which first appear in the northern Panama Bight in April migrate rapidly northwest to Central America and south to the Gulf of Guayaquil. The proportions which migrate in these directions vary considerably from year to year, this perhaps being dependent on differences in the sea-surface temperatures. SPANISH: Durante el período de 1952-1964 se liberó a través de todos los límites de distribución de la pesquería en el Océano Pacífico oriental un total de 59,547 aleta amarilla y 90,412 barriletes marcados. La mayoria de los peces fueron liberados de barcos de carnada comerciales, o en viajes regulares de pesca o en viajes en los que se fletaron los barcos para capturar atunes y marcarlos. De estas líberaciones se recapturaron 8,397 aleta amarilla y 4,381 barriletes. Parece que haya dos grupos principales de aleta amarilla en el Océano Pacífico oriental. Sin embargo, existe una entremezcla considerable entre los peces de los dos grupos. Los peces del grupo septentrional (costa occidental de Baja California, Golfo de California y Islas Revillagigedo) aparecen primero en las Islas Revillagigedo alrededor de abril, y durante la primavera y el verano se desplazan al norte a lo largo de la costa de Baja California y durante el otoño al sur a lo largo de la costa. Los reclutas del grupo meridional (Islas Tres Marias hasta el norte de Chile) aparecen en muchas partes o continuamente a lo largo de la mayoría de la costa. Los peces que aparecen primero en la región septentrional del Panamá Bight en abril se desplazanrápidamente al noroeste a la América Central y México y al sur al Golfo de Guayaquil. Parece también que existen dos grupos principales de barrilete en el Océano Pacífico oriental. Los peces del gr upo septentrional (costa occidental de Baja California, Golfo de California e Islas Revillagigedo )realizan casi la misma migración que el atún aleta amarilla de la misma área, pero aparentemente la mayor parte del barrilete se desplaza luego al Océano Pacífico central durante el otoño y/o en el invierno. Los reclutas al grupo meridional (América Central al norte de Chile) aparecen en su mayoría en el Panamá Bight o cerca a este lugar. Los peces que aparecen primero en la región septentrional del Panamá Bight en abril se desplazan rápidamente al noroeste a la América Central y al sur al Golfo de Guayaquil. Las proporciones que se desplazan en estas direcciones varían considerablemente de año a año; tal vez esto depende en las diferencias de temperatura de la superficie del mar.(PDF contains 227 pages.) | This article is bilingual and contains both Spanish and English translations.