Resumo em Inglês:

From a study of the variation of nitrates in the soil known as terra roxa misturada (mixed purple soil), the following conclusions were drawn : a) The nitrate content of this soil reveals a periodic variation through the year. The same kind of variation is expected in the majority of S. Paulo soils, because the climate, with minor exceptions, is fairly uniform over the State. b) As nitrification proceeds at a higher rate in the hot wet (September-May) than in the cool dry season (May-September), nitrates accumulate in the soil during the first period and disappear in the second. However, as an exception to the above rule, there appeared to be a fall in nitrates during December. This may have been due, either to leaching by rain, or to absorption by weeds, then in their growing period in the experimental fields. Since inorganic nitrogenous fertilisers do not generally give good results in the State of S. Paulo, when applied at the beginning of the rainy season, it is logical to attribute the decrease in nitrogen content to leaching, although the investigation did not lead to a conclusive explanation. c) This study did not support the view of an upward migration of salts in our soils during the dry months, since a steady level of nitrate content was observed during this period. d) Although the author was able to establish an association between nitrate losses and rainfall, it was not possible to determine the relation quantitatively.

Resumo em Português:

Foi continuado o ensaio do desbaste dos ramos inferiores do cafeeiro, instalado na Estação Experimental Central de Campinas, em 1932. O ensaio compreende duas séries : a) desbastada ; b) não desbastada. Cada série se compõe de 5 repetições com 25 cafeeiros cada uma. A variedade em cultivo foi a Coffea arabica L. var. typica Cramer. A série desbastada foi mantida sem os ramos primários até uma altura de 50 cm do solo. Na série não desbastada não se interferiu de modo algum nessa parte da planta. As colheitas foram iniciadas em 1935. A série não desbastada produziu significativamente mais, no período todo examinado, isto é, em dezesseis safras (1935-1950). Não houve grande diferença no tamanho das sementes. A maturação foi um pouco apressada na série desbastada. O ensaio demonstra que não houve vantagem em se fazer esta operação.

Resumo em Inglês:

The experiment, begun at the Central Experiment Station at Campinas in 1932, on the pruning of the lower branches of coffee plants, has been continued. The trial contains two series, a) pruned and b) not pruned. Each series consists of five replicates, each with 25 coffee plants. The variety is Coffea arabica L. var. typica Cramer. The pruned trees were kept free from primary branches to a height of 50 cm. The unpruned trees were left entirely untouched in this region. Harvesting began in 1935. The unpruned trees have yielded significantly better (P = 5%) over the period of the 16 years of the trial (1935-1950). There was no great difference in size of seeds. Ripening was advanced a little in the pruned trees. The experiment showed that there was no advantage to be gained by pruning ; on the contrary, the operation appears to be prejudicial to the yield.

Resumo em Inglês:

This paper was written primarily to illustrate the process of fitting constants to non-orthogonal data. The design of the experiment, on the pruning of lower branches of coffee-trees, was systematic (see plan at the beginning). Three constants were fitted, representing respectively the treatment contrast, the difference between upper and lower half of the field and the linear gradient of fertility across the field. The use of the residual sum of squares for the estimation of error is not, of course, logically correct but it is unlikely to lead to seriously wrong conclusions if caution is exercised. In the event, the procedure failed to eliminate any soil heterogeneity (see Analysis of Variance, p. 288). Inspection of the data showed that much of the heterogeneity would have appeared in a quadratic term in the gradient. When, as here, the number of data is very small, it is particularly dangerous to allow the data to suggest the scheme of adjustment, because this will lead to an over-estimation of the precision of the experiment. The conclusion was that not pruning the lower branches of tree gave an increase in yield of 104 ± 50 kg (dry fruits) per plot, with a general mean of 743 kg per plot.

Resumo em Português:

As variedades de batatinha Dar, Oka, Bem, Pionier e Kolobrzeskie, foram recebidas da Polônia, para verificação do seu comportamento sob as nossas condições, em confronto com a variedade "Eigenheimer", já conhecida (1). Com êsse objetivo, foram instaladas oito experiências, sendo três em Capão Bonito, em solo sílico-argiloso, três em Louveira, em salmourão, e duas em Indaiatuba, em terreno sílico-argiloso. Das observações realizadas durante o período vegetativo, e dos resultados da produção, conclui-se o seguinte : a) tôdas as variedades apresentaram película amarelada e que se tornou verde à ação da luz ; b) a folhagem da variedade Kolobrzeskie se mostrou de um verde-claro e de porte médio, contrastando com a Pionier, que se mostrou de um verde forte e porte avantajado ; c) a Kolobrzeskie e a Pionier revelaram boa resistência à Phytophthora injestans e Alternaria solani, principalmente quando comparadas à "Eigenheimer", ao passo que a Oka mostrou ser pouco resistente ; d) a variedade Bem se mostrou mais suscetível às manchas internas de orígem fisiológica (chocolate), sendo que a Pionier revelou pequena tendência a êsse defeito ; e) as variedades mais produtivas foram, por ordem decrescente (média de 6 experiências) : "Eigenheimer" Oka, Kolobrzeskie, Bem, Pionier e Dar; f) as maiores percentagens de tubérculos graúdos foram fornecidas pela Kolobrzeskie e Bem, e, de refugo, pelas variedades Oka, Dar e "Eigenheimer".

Resumo em Inglês:

Seed tubers of Irish potato varieties Dar, Oka, Bern, Pionier and Kolobrzeskie, received from Poland, were tested in the State of São Paulo with the best known Dutch variety, Eigenheimer. Eight trials were conducted in three different localities : Capão Bonito, Louveira and Indaiatuba. Varieties Kolobrzeskie and Pionier showed good resistance to both early and late blight. On the contrary, the varieties Eigenheimer and Oka were susceptible. Variety Bem has shown some physiological disorders through spotting of tuber flesh. Little tendency to such disorders was revealed by variety Pionier. The best yielding varieties were Eigenheimer, Oka, Kolobrzeskie, Bern, Pionier and Dar. Variety Kolobrzeskie and Bem yielded larger percentage of big-sized tubers;. Oka, Dar and Eigenheimer produced larger percentages of small-sized tubers.

Resumo em Inglês:

The cultivation of coffee in the American coffee producing countries is not faced with any serious handicap. The future can not be far distant, however, when it will be necessary to establish new plantations back on the high-priced old exploited lands. Need will be felt for improved varieties. At the same time, it is not known if in a near future the American coffee growers will not be in trouble with diseases as terrible as Hemileia, which the present age of transport cannot restrict to non-American areas. In the program of coffee improvement, interspecific crosses are expected to take a very important place. The introducing of desired characteristics of other species into Coffea arabica by hybridization is made difficult by the fact that, while C. arabica is self-fertile, the other species are self-sterile. It is known, also, that the high cup quality C. arabica species, with 44 somatic chromosomes, gives sterile triploid hybrids (2n = 33) when crossed to the leaf disease resistant Coffea canephora and other diploid (2n = 22) species. Very seldom, however, do the triploids produce seed, as a result of back-cross to C. arabica either through open or controlled pollination. The cytological constitution of the plants obtained from these seeds is variable ; some triploids give rise to seedlings having mostly a chromosome number around 44 ; the progeny plants from other hybrids have this number mostly around 55. Numerous aneuploids have been found among these progenies. Attention has been given to the plants derived from the hybrids as to their developmental and production characteristics. At least two 44-chromosome plants have shown to be interesting in these respects and one of them, productive and self-fertile, showed up characteristics very similar to the maragogipe variety of C. arabica. More detailed comparative observations are necessary ; however, the obtaining of such a plant proves that the triploids are a permanent source of new cytological combinations that can be used in the future in the search for new vigourous and disease resistant coffee plants with high cup quality.

Resumo em Inglês:

This paper presents preliminary results 01 chemical fertilizer experiments conducted at Campinas and Pindorama Experimental Stations on production of stems with leaves of the Murakami ramie (Boehmeria nivea) in two types of soils in the State of São Paulo. In CampiDas, on soil of the "roxa misturada" type, different effects of the treatments in the increasing of the production of stems with leaves have been found. In Pindorama, on soil oi the "Arenito Bauru" type, the results of experiment only showed a significant effect of phosphorus in increasing the production of stems with leaves.

Resumo em Inglês:

X. campinense n. sp. is described. It is a Xiphinema closely resembling X. pratense Loos, 1949, from which it is distinguished by its measurements, by the absence of any cuticular transverse striatum as well as by the number and location of the caudal papillae.

Resumo em Português:

Descrevemos os princípios básicos do planejamento de experiências de rotação. Apontamos a necessidade de incluir na experiência tôdas as fases das rotações em todos os anos. Mostramos o motivo por que, geralmente, não podem ser aproveitados os delieneamentos complexos desenvolvidos para experiências de um só ano. Discutimos uma experiência de rotação com milho, algodão e macuna.

Resumo em Inglês:

This paper explains the principles of planning rotation experiments. It includes a description of a rotation experiment with maize, cotton and mucuna, which is now beginning at two stations in the State of São Paulo. An account of this experiment, together with a discussion of its statistical analysis, will appear elsewhere in English.