Maria do Carmo de Salvo Soares Novo

ENXERTIA DE COFFEA ARABICA SOBRE PROGÊNIES DE C. CANEPHORA E DE C. CONGENSIS NO CRESCIMENTO, NUTRIÇÃO MINERAL E PRODUÇÃO

Grafts of Coffea arabica L. onto C. canephora Pierre have been routinely used in regions infested with nematodes, due to the resistance of C. canephora to these pathogens. In the present work, growth, mineral nutrition and yield of two C. arabica cultivars grafted on C. canephora and C. congensis were evaluated in fields free from nematodes, in three coffee growing regions of Sao Paulo State, Brazil. Catuai Vermelho IAC H 2077-2-5-81 and Mundo Novo IAC 515-20 (two cultivars of C. arabica) were grafted on nematode resistant lines Apoata IAC 2258 and IAC 2286 of C. canephora and on IAC Bangelan colection 5 of C. congensis. Plants not grafted were used as controls, and plants grafted onto their own roots were also evaluated. Grafted cultivars after five years grew better and had higher yield than the ungrafted ones, specially the Catuai cultivar. Seasonal growth (plant height) was faster during spring and summer, for all treatmentes. In general, grafting increased height throughout the year, mainly during fall and winter seasons. Leaves of grafted plants had higher potassium and lower manganese content than ungrafted ones. Levels of other nutrients were not consistently affected by grafting.

Produção de mudas de alface em bandejas e substratos comerciais

The effect of four commercial substrates in polystyrene trays with 200 and 288 cells, was evaluated on the production of seedlings of lettuce (Lactuca sativa cv. Vera) in a plastic greenhouse, from 15/01 to 13/02/03, in Campinas, Sao Paulo State, Brazil. The treatments consisted of factorial combinations of four commercial substrates (Plantmax HA, Hortimix folhosas, Golden Mix 47 and, Vida Verde Tropstrato hortalicas) and two cell sizes (200 and 288 cells). The experimental design was a randomized complete design, with the plots split with each part subdivided for the evalution time, with three repetitions, each beign made up of a tray. At 5; 10; 15 and 20 days after germination, twenty random plants from each plot were evaluated for their stem height, number of leaves, clod stability of substrate and foliar area. Fifteen and twenty days after germination, the lettuce seedlings grown in Plantmax presented better development characteristics than other substrates. Seedlings produced on trays with 200 cells presented greater number of leaves and bigger leaf areas than those produced on 288 cells trays.

Crescimento e competitividade de biótipos de capim-colchão resistente e suscetível aos herbicidas inibidores da acetil coenzima A carboxilase

Abstract€–€The€objective of this work was to compare the growth and the competitive ability of two crabgrass( Digitaria ciliaris ) biotypes, one resistant (R) and other susceptible (S) to the acetyl coenzyme A carboxylaseinhibiting herbicides. Biotypes growth was determined by collecting the plant dry mass at 14, 21, 25, 28, 34, 42, 49,57, 65, 72, 78, 86, 101, 111, and 118€days after emergence (DAE). Data of dry mass were adjusted to a logisticmodel, and were also used to calculate the absolute growth rate. Five experiments were installed to evaluate theintraspecific and interspecific competitive ability, using the substitutive method. The biotypes R and S werecompared between themselves and each one of them with the soybean crop seeded in the same day or sevendays after the seeding of the weeds. Plant proportions between species or biotypes used were: 5:0; 4:1; 3:2; 2:3;1:4, and 0:5. The biotypes presented similar dry mass accumulation, absolute growth rate and interspecificcompetition, and the reduction of soybean mass was similar in the presence of R and S crabgrass biotypes, whichsuggests that R and S crabgrass biotypes have the same ecological adaptability.Index term:

CONSERVAÇÃO E GERMINAÇÃO DE SEMENTES E DESENVOLVIMENTO DE PLÂNTULAS DA PEREIRA PORTA-ENXERTO TAIWAN NASHI-C

Taiwan Nashi-C (Pyrus calleryana Decaisne), an oriental rootstock pear, was investigated for 30 months in respect to seed cold storage, longevity, germination and seedling development. The seeds removed from mature fruits, were washed, dried, treated with Thiran and placed in closed botles under controlled environment (5-10oC) for thirty months. The seeds were stratified trimestrially over moist cotton substrate at 5oC for 40-60 days. One hundred percent germination ocurred until the 9th month, decreasing to 97, 94, 83 and 76% in the 12th, 18th, 24th, and 30th month of seed cold storage, with seedling emergency of 88, 89, 81, 76 and 70% respectivelly. The seedlings presented a rapid and vigorous growth, with average height of 141.5cm and diameter of 11.9mm, after twelve months from emergency. About 20% of the population showed abnormalities, with undesirable segregation.

Desempenho de três cultivares de almeirão sob cultivo protegido

Cichorium intibus L. is an Asteraceae very similar to endive, distinguished by longer and narrower leaves covered with pile and bitter flavored. An experiment was carried out in a plastic greenhouse, to evaluate the performance of the Folha Larga, Pao-de-Acucar and Catalonha cultivars, from July to September/2001, at IAC, Campinas, Brazil. A split plot design was used with the cultivars in the main plots and sampling data as subplots. Each main plot and subplot was randomized in three replications. At 50; 57; 64 and 71 days after sowing, ten plants of each subplot were taken and their height, leaf number, foliar area and fresh and dry matter weight were measured. Yield of leaves per linear meter was also evaluated. No difference in leaf number per plant was observed but interaction was found among cultivars and time of evaluation for foliar area, and fresh and dry matter weight. Catalonha was the tallest and more yielding cultivar but Pao-de-Acucar presented the highest values of fresh and dry matter weight. Pao-de-Acucar also presented highest foliar area. Based on foliar area, chicory should be harvested withing 64days after sowing date. Obtained data indicate that chicory, cultivated in a plastic greenhouse, is a new and good alternative to this production system.

Efeito da vinhaça no desenvolvimento inicial de girassol, mamona e amendoim em casa de vegetação

O trabalho teve como objetivo verificar o efeito da aplicacao ao solo da vinhaca, residuo da industria canavieira, na emergencia de plântulas e no desenvolvimento inicial de girassol, mamona e amendoim - culturas com potencial de utilizacao na sucessao com a cana-de-acucar. O experimento foi desenvolvido em vasos com terra, dispostos em blocos ao acaso, sendo cada especie avaliada individualmente, em esquema fatorial 2 x 3, em quatro repeticoes. Os tratamentos originaram-se de combinacoes da aplicacao ou nao da vinhaca (150 m3 ha-1) sobre tres cultivares de girassol (IAC Iarama, Catissol e Helio 358), de mamona (Guarani, Iris e IAC 2028) e de amendoim (IAC Caiapo, Runner IAC 886 e Tatu). Determinaram-se a velocidade de emergencia de plântulas, a primeira contagem e a porcentagem final de emergencia, alem do comprimento e biomassa seca da parte aerea de plantas, em avaliacao realizada aos 30 dias apos a semeadura. Os resultados atestam que, sob condicoes de vegetacao, a aplicacao de 150 m3 ha-1 de vinhaca ao solo e prejudicial a emergencia e ao desenvolvimento inicial de plantas de amendoim e em menor grau, de girassol, independentemente da cultivar estudada; para mamona, a interferencia ocorre de forma positiva, principalmente sobre as variaveis relacionadas ao vigor inicial das plântulas, com melhor desempenho das cultivares IAC 2028 e Iris.

Efeito da adição de palha de cana-de-açúcar e da aplicação de vinhaça ao solo no desenvolvimento inicial de três cultivares de mamona

The experiment aimed to verify whether the addition of sugarcane mulch residue and vinasse on soil could affect seedling emergence and the initial development of three castor bean cultivars. The experiment was carried out using pots with soil, inside a glasshouse, in Campinas, State of Sao Paulo, Brazil, and arranged in randomized complete blocks with four replications. A three way combination of quantities of sugarcane (Saccharum spp) cv SP 803280 mulch residue equivalent to 0, 5, 10, 15 and 20 t.ha-1, quantities of vinasse equivalent to 0 and 150 m3.ha-1 and the castor bean cultivars IAC-Guarani, Iris and IAC-2028 were evaluated. Each day for 30 days, seedling emergence was counted and at the end, the speed of emergence index (SEI) and the final percentage were calculated. It was concluded that the application of vinasse decreased the seedling emergence of the castor bean cultivars IAC-Guarani, Iris and IAC-2028 but there was no damage in the seedling development with this residue. The addition of sugar cane mulch residue did not affect emergence but increased the initial development of castor bean cultivars.

NITROGÊNIO E POTÁSSIO NA FIXAÇÃO SIMBIÓTICA DE N2 POR SOJA CULTIVADA NO INVERNO

The objective of these experiments was to study the effect of nitrogen and potassium fertilizations on the response to nodulation, nitrogen fixation, nitrogen seed content and yield of two soybean cultivars planted during the winter season. They were installed on the following soils: Eutric Lixisol (Mococa) and Rhodic Ferralsol (Ribeirao Preto and Votuporanga, SP, Brazil). The treatments consisted of three rates of nitrogen (0, 50 and 100 kg.ha-1 of N) as urea, three of potassium (0, 30 and 60 kg.ha-1 of K2O) as chloride and two soybean cultivars (IAC-8 and IAC-14). The experimental design was a random factorial with four replications. Soybean seeds of all treatments were inoculated with a commercial inoculant. At flowering, plants were sampled to evaluate nodulation and nitrogenase activity. At maturity, plants were harvest and seeds weighed.The results showed that inoculation did not provide the amount of nitrogen required to maximize soybean yield in the winter. The nitrogen treatment reduced nodulation and nitrogen fixation, but increased seed yield at the three localities. Potassium fertilization did not have any significant effect on nodulation, nitrogen fixation and yield of soybeans. Increased however dry matter weight and number of nodules of the cultivar IAC-14.

Repelência e toxicidade de Cyperus iria L., em início de florescimento, ao gorgulho Sitophilus oryzae

The aim of this work was to evaluate the repellence and toxicity of Cyperus iria L., at beginning of flowering, to Sitophilus oryzae (L.). Two bioassays were used to evaluate the powders produced from the roots, shoots and inflorescence of C. iria, mixed with wheat grains in concentrations of 0, 1, 2 and 5%. A third bioassay evaluated the repellence of the aqueous extracts produced from the powders of C. iria impregnated in paper in concentrations of 0, 0.1, 0.5 and 1.0 mg of plant cm-2. The powders produced with any structure of C. iria repelled S. oryzae. The repellence and toxicity depended on concentration and plant structure used in the production of the powder. The repellence was higher with 5% of root and lower with any other concentration of inflorescence. With roots, it was present for periods longer than 150 days. The mortality and reduction in progeny were higher when the roots of C. iria were tested. All treatments reduced the progeny of S. oryzae for up to 60 days, with the exception of the concentration of 2% of the root. When aqueous extracts from the structures of C. iria were employed, repellence was verified for roots at 0.1 and 0.5 mg cm-2, for aerial parts at 0.5 mg cm-2, and flowers at 0.5 and 1.0 mg cm-2. The treatment of grains using powders from C. iria was more efficient in the control of S. oryzae than the extracts applied on paper.

Resistance of Bidens subalternans to the acetolactate synthase inhibitor herbicides used in soybean crop

The continuous and prolonged use of products with the same mechanism of action can provoke the manifestation of resistant biotypes. In horder to verify possible new cases, as well as alternatives for prevention and control, seeds of Bidens subalternans were collected at São Gabriel D’ Oeste (MS) region at plants that survived continuous treatments which sistematically ALS inhibitors. Through an experiment performed in pots inside a greenhouse, a resistant biotype was compared to a susceptible one when submitted to herbicides with different mechanisms of action and applied at post emergence. These herbicides were applied at doses zero, one, two, four and eight times the recommended dosage. Twenty days after, the control and the green weight production were analysed aiming to get the dose-response curves as well as the resistance factor. The biotype from the area with repeated application of ALS inhibitors showed a high level of resistance to chlorimuron-ethyl and imazethapyr, demonstrating therefore to be a carrier of crossed resistance to the ALS inhibitors of the sulfonilurea and imidazolinona groups. However, this biotype was controlled by fomesafen, lactofen, bentazon, ammonium glufosinate and glyphosate.