Varieties tested were Valencia, Ruby and Parson brown. The field design used was a randomized block with 4 replications and the treatments given were: control, N, NPK, NPK and dolomite and NPK and micro-nutrient fertilizer. The effect of fertilizers on mean weight of oranges for all varieties was non-significant; NPK and NPK and dolomite treatments increased the juice content of Parson brown significantly; NPK and dolomite increased the juice content of Valencia and Ruby oranges and increased the pH of Valencia and Parson brown. NPK, NPK and dolomite, and NPK and micro-nutrient increased the number of Valencia, Ruby and Parson brown oranges harvested per tree significantly (at 1 % LSD)

Saginaw and Sanilac navy beans (Phaseolus vulgaris) were grown at various combinations of high and normal levels of Zn, Cu, Fe, and Mn in sand culture. Saginaw variety grew normally at 5.0 ppm Zn, while the growth of Sanilac was extremely reduced. This difference was manifested in plant height, leaf number, and root and shoot weight. In addition, a differential Fe.Cu interaction induced by high Cu levels was observed. These differences apparently were not related to differential uptake or distribution of the nutrients, since the differences in elemental composition of the two varieties did not seem to be of sufficient magnitude to be biologically significant. The Saginaw-Sanilac nutrient interaction relationship is proposed as a valuable system for the study of nutrient utilization since these two varieties differ in their tolerance to high as well as low levels of Zn and other unbalanced micronutrient conditions.

Six oat, Avena sativa L., varieties grown in sand in a growth chamber were supplied with a complete nutrient solution. Consistent and highly significant varietal differences developed in length of internodes. Although length of internodes was affected by photoperiod, temperature, age, spacing, and planting depth, this is not considered a serious obstacle to use of internode length in varietal purity testing provided environmental conditions can be controlled. Plants of the ‘Russell’, variety grown with continuous light and a temperature of 27 ± 2 C had first leaf internodes (above the first foliar leaf node) three to five times as long as those of other varieties. Second leaf internodes of ‘Orbit’ were nearly twice as long as those of ‘Garry’ or ‘Niagara.’ Both Orbit and ‘Rodney’ had long third leaf internodes whereas ‘Clintland’ had the longest fourth leaf internodes.

The behavior of three São Paulo cotton varieties (IAC 12, IAC 13 and IAC RM3), which differ themselves in vegetative cycle and nutrient requirements, after receiving three levels of complete N, P and K fertilization, were compared under cultivation on latossolic B "Terra Roxa" soils. The inclusion of the variety IAC RM3, resistant to Fusarium wilt, was made considering a possible spreading of this disease, now common in sandy soils, to clay soils. A basic dose of NPK fertilizer, containing 20, 45 and 40 kg/ha of N, P2O5 and K..O respectively, induced a significant increase in cotton yield, in relation to control plots, where no fertilizer was added. Among the varieties, IAC 13, with longest life cycle, presented the highest yield, followed by IAC 12, with intermediate cycle length. IAC RM3 was the less productive. There was also a significant increase in the weight of seeds and bolls due to this basic dose. No appreciable effect of a possible interaction between varieties and fertilization could be noticed. A double dose of fertilizer produced further increase in yield, except in the case of IAC RM3, in which additional amount of fertilizer induced a slight yield reduction and many plants showed signs of potassium defficiency. Considering the fiber characteristics the tested varieties differed significantly. IAC 12 had the highest mean of lint percentage, while IAC 13, on the average, was the best for Micronaire and Pressley indices, confirming previous unpublished determinations. | São relatados resultados de três ensaios de variedades paulistas de algodoeiro adubadas com diferentes doses dos elementos N, P e K, conduzidos em Latossolo Roxo não infestado pelo fungo causador da murcha de Fusarium, em 1965/66. As variedades IAC 13 e IAC 12 apresentaram ciclo vegetativo mais longo que a IAC RM3. A variedade IAC 13 superou em produção a IAC 12, e a variedade IAC RM3, que apresentou sintomas mais intensos de deficiência de potássio, obteve a menor média de produção. A dose básica de adubação, correspondente a 20, 45 e 40 kg/ha de N, P2O5 e K2O, aumentou significativamente a produção. Em média, a dose dupla proporcionou pequeno aumento, quando comparada com a básica, nas variedades IAC 12 e IAC 13. Em um dado ensaio, essa dose mostrou--se inferior à básica, quando aplicada à variedade IAC RM3. A variedade IAC 12 apresentou a mais alta média de porcentagem de fibra. A IAC 13 foi a melhor quanto aos índices Micronaire e Pressley. A adubação utilizada não concorreu para melhorar nenhuma dessas características; contribuiu entretanto para aumentar o pêso dos capulhos e das sementes.