Altino Aldo Ortolani

Estimativa de horas de frio abaixo de 7 e de 13°C para regionalização da fruticultura de clima temperado no estado de São Paulo

Estimativa e mapeamento do numero de horas com temperaturas abaixo de 7 e 13°C no Estado de Sao Paulo e analise comparativa do comportamento de fruteiras de clima temperado constituem os objetivos do presente trabalho. Foi cotado o numero de horas com temperaturas inferiores a 7 e 13°C, indices considerados limites necessarios a dormencia dessas plantas. Foram selecionados termogramas de doze postos agrometeorologicos do Instituto Agronomico, situados em altitudes variaveis entre 25 e 1.000m, correspondentes ao periodo 1964-1973. Estabeleceram-se equacoes para estimativa do numero de horas com temperaturas inferiores a 7°C (HF-7) e 13°C (HF-13) em funcao da temperatura media do mes de julho, cujos coeficientes de correlacao foram de -0,88 e -0,93, respectivamente. Com base nessas equacoes foram mapeadas as isolinhas de HF-7 e HF-13 para o Estado de Sao Paulo, encontrando-se desde valores medios anuais de HF-7 inferiores a 20 horas, caracteristicos das regioes de transicao de clima mesotermico a megatermico do Planalto Ocidental e das regioes mais baixas do norte e oeste do Estado, ate valores anuais de HF-7 superiores a 200 horas, caracteristicos das areas acima de 1.500 metros de altitude no Sul do Estado, na serra da Mantiqueira, limitrofe com Minas Gerais, e na serra do Mar, limitrofe com o Rio de Janeiro. Com base na introducao de diferentes frutiferas de clima temperado no Estado de Sao Paulo, verificou-se uma relacao muito grande entre os indices HF-7 e HF-13 mapeados com o comportamento e potencialidade de exploracao comercial.

Early selection for growth vigor in rubber tree genotypes in northwestern São Paulo State (Brazil)

Forty-five genotypes (clones) of rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.] of different origins were assessed for efficiency of early selection at the Votuporanga Experimental Station in northwestern Sao Paulo State, Brazil, using a randomized complete block design with three replications and six plants per plot. Girth at 120 cm above the highest point of the grafting union of each tree was taken at ages 12, 24, 36, 48, 60, 72, 84 and 96 months. Highly significant differences in girth were detected among the genotypes at all ages evaluated, except for 12 months. Estimates of genetic variance for two age sets showed a substantial increase with age, while the genotype variation decreased. Selection made at 24 months proved to be the most efficient, giving a superior gain per unit of time.

Growth trends, genotype-environment interaction and genetic gains in six-year-old rubber tree clones (Hevea) in São Paulo State, Brazil

Budwood from seven different clones of rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.] was planted in replicated trials in four different test sites in the plateau region of the state of Sao Paulo, Brazil. The clones represented a range of imported germplasm, whereas the locations were selected to represent a range of rubber growing areas. Girths were measured for six years consecutively, before the initiation of tapping for latex. Total number of latex vessel rings (lvr) and bark thickness (bt) were measured at six years. The largest average for all characters was observed in Matao. Overall means for girth, total number of latex vessel rings and bark thickness at six years were 35.26 cm, 11.30 units and 4.83 mm, respectively. Both the test sites and clones showed statistically significant differences in girth, lvr and bt values. There were significant clone x site interactions. Girth at one year was not a reliable predictor of future field performance. Broad sense heritability for girth was 0.16, and for lvr and bt it was 0.28 and 0.40, respectively, at six years. Repeatability was quite high, from 0.52 to 0.75 for all characters in all years. When two clones out of seven were selected, expected genetic gain in girth was about 2.0%; for lvr and bt it was 7.0% and 14.6%, respectively.

Variabilidade genética da produção anual da seringueira: estimativas de parâmetros genéticos e estudo de interação genótipo x ambiente

Selecionaram-se dezenove genotipos de seringueira (Hevea brasiliensis Muell. Arg.) considerados como os melhores em vigor e producao em uma populacao de pes francos estabelecidos no campo de ensaios da Estacao Experimental de Pindorama, com o objetivo de estudar a variabilidade genetica e ambiental e a interacao genotipo x ambiente sobre a producao durante cinco anos. Com base na analise da variância anual e conjunta, estimaram-se parâmetros geneticos para producao, na tentativa de quantificar o ganho genetico com a selecao, e as correlacoes geneticas e fenotfpicas das producoes ano a ano. Os resultados das analises da variância dentro de anos mostraram efeitos significativos para genotipos, sendo os efeitos da interacao genotipo x ambiente altamente significativos. As estimativas de herdabilidade, no sentido amplo, ao nivel de medias de parcelas, foram altas, com amplitude de 0,57 a 0,77, respectivamente, para o segundo e quinto ano de producao. As maiores percentagens de ganho genetico foram obtidas no primeiro e quinto ano de producao, 39,03 e 27,57 respectivamente. Correlacoes geneticas e fenotipicas entre anos de sangria foram altas e significativas. Os altos valores de herdabilidade e ganho genetico para o primeiro ano de sangria indicam que a selecao massal conduzida nesta fase proporciona, efetivamente, maior ganho na selecao.

Desempenho preliminar de clones de seringueira na região de São José do Rio Preto, planalto do estado de São Paulo

Neste trabalho, e apresentado o desempenho de nove anos de desenvolvimento e producao dos clones de seringueira [Hevea brasiliensis (Willd. ex. Adr. de Juss.) Muell. Arg.], a saber: AVROS 1328, PB 235, PB 217, GT 1, RRIM 701, IAN 873, Tab 821, IAC 15, Tab 804, IAC 222 e, como testemunha, RRIM 600. No experimento, instalado na Fazenda Agua Milagrosa, municipio de Tabapua, sob o delineamento de blocos casualizados com seis repeticoes, estudaram-se os seguintes caracteres: producao de borracha seca; vigor, expresso pela circunferencia do caule; espessura de casca e arvores com seca do painel. Com relacao a producao dos onze clones testados, PB 235, Tab 804, RRIM 701 e AVROS 1328 produziram, respectivamente, 113, 45, 38 e 32% a mais em relacao ao RRIM 600, em gramas/arvore/corte na media de quatro anos de sangria, onde, a partir do segundo ano, as plantas foram estimuladas. A maior parte desses clones se mostrou vigorosa, com caracteres secundarios aceitaveis, tais como: espessura de casca virgem, arvores secas, baixa incidencia de quebra pelo vento e baixa suscetibilidade de doencas de painel e folhas. O desempenho do GT 1 e do IAC 222, embora vigoroso, nao foi bom. RRIM 701 e IAC 15 apresentaram alta incidencia de seca do painel; entretanto, o incremento da circunferencia na sangria foi alto para esses clones.

Genetics of anthracnose panel canker disease resistance and its relationship with yield and growth characters in half-sib progenies of rubber tree (Hevea brasiliensis)

Rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell-Arg] anthracnose panel canker disease resistance, caused by Colletotrichum gloeosporioides (Penz.) Sacc., and growth and yield characters were assessed at three years old in the nursery, in 18 half-sib progenies. There were highly significant (P < 0.01) genetic differences among progenies for most characters. The genetic component of variance accounted for 3.37, 6.07, 12.74, 12.13, 19.82 and 3.58% of the phenotypic variance for anthracnose-infected area, anthracnose lesion stripe length, yield, girth, virgin bark thickness and total number of latex vessel rings, respectively. Narrow-sense heritability estimates for the above characters were 13.45, 24.30, 50.97, 48.52, 79.30 and 14.30%, respectively. No significant genetic correlations were found among anthracnose panel canker resistance, yield and growth characters. The frequency distribution of anthracnose-infected area and anthracnose lesion stripe length suggests polygenic control. Selecting the best three progenies out of 18 progenies would result in a genetic gain of 12.87 and 24.24% for infected area and lesion stripe length, respectively. The best five selected individuals out of 50 individuals within each progeny would result in a genetic gain of 9.47 and 24.62%, with a total gain of 22.34 and 48.87% for these two characters, respectively.

Phenotypic stability and genetic gains in six-year girth growth of Hevea clones

7 ABSTRACT - Rubber tree (Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.) budgrafts of seven clones were evaluated on five contrasting sites in the plateau region of the Sao Paulo State, Brazil. The objective of this work was to study the phenotypic stability for girth growth. The experimental design was a randomized block design with three replications and seven treatments. Analysis of variance of girth at six-year plant growth indicated a highly significant clone x site interaction. Only linear sites and clone x site components of clone x year interaction were significant, indicating that the performance of clones over sites for this trait could be predicted. The clones GT 1 and PB 235 showed the greatest stability in relation to girth growth, with foreseen responses to change, introduced in the sites. The clones PB 235 and IAN 873 showed significative difference in relation to regression coefficient, representing clones with specific adaptability on favorable and unfavorable sites respectively. The clone GT 1 became the most promissory one in the study of stability and adaptability even showing low girth growth. Expected genetic gains from planting sites, along with estimates of clonal variance and repeatability of clonal means are generally greatest or close to the greatest when selection is done at the same site.

Desempenho de novos clones de seringueira: III. seleções promissoras para a região de Votuporanga, Estado de São Paulo

6 RESUMO - E apresentado o resultado da primeira selecao de 25 clones de seringueira ( Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.), a maior parte constituida de introducoes de diferentes origens. Apos multiplicados, foram avaliados em experimentos do tipo pequena escala, obedecendo ao deline- amento de blocos ao acaso, instalado na Estacao Experimental de Votuporanga, SP. Os caracteres avaliados foram: producao de borracha seca, vigor expresso pelo perimetro do caule, espessura de casca e numero de aneis de vasos laticiferos. Com relacao a producao de borracha seca, destacaram-se os clones IAN 3156, IAC 40, 7/6, 3/5 e 3/1, produzindo 124%, 105%, 27%, 26% e 19% superiores em relacao ao RRIM 600, recomendando-se seu plantio em pequena escala na regiao de Jau. Caracteres secundarios tais como o vigor, espessura de casca e numero de aneis de vasos laticiferos dos clones testados sao tambem discutidos. Sugere-se sua avaliacao em experimentos do tipo grande escala com o objetivo de avaliar, alem da producao, outros caracteres secundarios para futuras recomendacoes no Estado de Sao Paulo. ABSTRACT - The present paper shows the results of the first selection of 25 rubber tree clones (Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.). Most of them are introductions, originated in selections obtained from different places. After multiplied, the clone evaluation was conducted in a small scale trial under a randomized complete block design established at Votuporanga Experimental Station in Sao Paulo State, Brazil. The evaluated characters were yield, vigour expressed by stem girth, bark thickness and number of latex vessel rings. The clones IAN 3156, IAC 40, 7/6, 3/5 e 3/1 were classified as high yielding in the first year of tapping. They produced 124%, 105%, 27%, 26% and 19% higher compared with the RRIM 600. The secondary characteristics, such as stem girth, bark thickness, and number of latex vessel rings of the tested clones are discussed. A complementary evaluation in large scale trials is suggested, aiming to evaluate besides yielding other secondary char- acters with purpose of future recommendation of planting materials to the industry.

Estimativa de produção de laranja valência pela adaptação de um modelo agrometeorológico

YIELD PREDICTION OF ORANGE CULTIVAR VALENCIA THROUGH ADAPTATION OF AN AGROMETEOROLOGICAL MODEL The influence of the hydric factor influence and the previous year yield relative to the potential (Yaa/Yp), yield was evaluated for orange cultivar Valencia/Cravo (Citrus sinensis Osbeck). The stages of dormancy, flowering and fruit set were considered in a multiplicative mathematic agrometeorological model with different sensitive indices (λ-values). Meteorological, phenological and crop yield data of an orchard in Matao, SP, Brazil, were analyzed. The obtained results indicated better performance of the model when the periods of dormancy were established in August - September, flowering in October November and fruit set in December - January. The magnitude of the sensitive index values showed that flowering (Oct - Nov) is the most sensitive period for water stress. In the model validation it was observed a good performance, with R 2 of 0.81 and d-index of agreement of 0.95.

Eficiência do uso da água por cultivares de arroz em duas densidades de plantio

This paper describes the water use efficiency for two rice cultivars IR-665-4-5-5 and IAC-1246, tilled in an Oxisol under two planting densities (0.30 and 0.60m between rows) at the Central Experimental Farm of Campinas. Actual evapotranspiration was determined by the field water balance (BRUNINI, GROHMANN; SANTOS, 4). The results indicated that the cultivar IR-665-4-5-5 with 0.30m between rows had the highest water consumption (about 616mm); but the cultivar IAC-1246 with 0.30m between rows had the highest water use efficiency followed by the cultivar IR-665-4-5-5 with 0.30m between rows. A close relationship was found between actual evapotranspiration and leaf area index for the higher density treatments.