Edison Martins Paulo

EFEITOS DOS PERÍODOS DE COMPETIÇÃO DO MATO NA CULTURA DO AMENDOIM: I. SAFRA DA SECA DE 1988

A field experiment was carried out at Adamantina, State of Sao Paulo, Brazil, to study different periods of weed competition with peanut. The treatments were 20: with and without weed presence through the crop cycle and those resulting from factorial combinations among presence and ausence of weed in the beginning of crop and the time of weed removal - 20, 30, 40, 50, 60, 70, 80, 90 and 100 days after sowing. Each plot was constituted of four lines, with common border among experimental units, with useful area reading 6.0 m2. Weed species, occurring with higher frequencies were Cyperus lanceolatus Poir., Digitaria horizontallis Willd., Brachiaria decumbens Stapf. and Portulaca oleracea L. The weed association with the peanut crop decreased pod and kernel yields and peanut dry matter. No weed effects were observed on harvest indexes and shelling percentages in any of the studied periods. A weeding operation done eight or 73 days after sowing, for treatments without and with weeds respectively, was sufficient for obtaining peanut pod yields statistically similar to those obtained when the peanut crop was maintained without competition during all cycle.

PRODUTIVIDADE DO CAFÉ APOATÃ EM CONSÓRCIO COM LEGUMINOSAS NA REGIÃO DA ALTA PAULISTA

Coffee (Coffea canephora Pierre) productivity was evaluated during three years of intercropping with five leguminous species: sunn hemp (Crotalaria juncea L.), Crotalaria spectabilis Roth., dwarf velvet bean (Stizolobium deeringeanum Bort.), soybean [Glycine max (L.) Merryl] and pigeon pea [Cajanus cajan (L.) Millsp.] in the western region of Sao Paulo State, from 1991 to 1993. Leguminous species were seeded 50 cm far from coffee shoot and incorporated at flowering stage. The treatments were arranged in a randomized complete block design with five replicates. Coffee yield was not affected when Crotalaria spectabilis, dwarf velvet bean and soya bean IAC 9 were used as interrow crop, but it was significantly decreased for pigeon pea and sunn hemp treatments. Linear correlation analysis showed that coffee yield was inversely correlated with leguminous dry biomass and positively correlated with coffee shoot height and stem diameter at the harvest year.

Deficiência de boro em mamona

During the summer season 1987/88, castor bean plants (Ricinus communis L.) var. IAC-80 growing at the Estacao Experimental de Agronomia da Alta Paulista, State of Sao Paulo, Brazil, showed some symptomus related to boron deficiency. The symptoms included leaf curling, necrosis of terminal bud, small fruit setting and necrosis in the stem. The symptoms occurred after a drought period. Plants were analysed after a new raining period. The nutrient concentrations were higher in plants with deficiency symptoms except for boron. The relations between boron and each one of the macronutrients were lower in plants with symptoms. Soil samples collected under deficient plants were lower in boron than samples collected under normal plants. Based on these informations and on the similarity with boron deficiency symptoms on other plants, it was conclued that the symptoms might be related to boron deficiency.

Efeitos dos períodos de competição do mato na cultura do amendoim: II. Safra das águas

The present research was carried out at the Nucleo de Agronomia da Alta Paulista, in Adamantina, State of Sao Paulo, Brazil, to study the effects of different periods of weed competition with peanut.The treatments were all possible combinations among the presence/absence of weeds (at the sowing time) and the following periods of weed removal: 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 days, after sowing. Each experimental plot was set up with four peanut lines (6.0 m2 of useful area). The main weed species occurring in the experimental area were: Cyperus lanceolatus Poir, Brachiaria decumbens Stapf., Commelina benghalensis L., Amaranthus viridis L., Eleusine indica (L.) Gaertn., Portulaca oleracea L., Digitaria horizontalis Willd and Solanum americanum Mill. The main effects of weed presence in the peanut crop was to decrease pod kernel yields and peanut population at harvest. No significant effects were observed on shelling percentages and peanut dry matter for any of the studied periods. Weeding control, carried out at 13 and 67 days after sowing, not taking into account initial weed presence was enough for obtaining peanut pod yield statistically similar to that observed when the peanut crop was maintained with no competition during all cycle. Pods and kernel yields and peanut population at harvest increased with weeding control at the sowing stage.

Influência da época de semeadura no crescimento, produtividade e outros fatores de produção em cultivares de amendoim na região da alta paulista

ABSTRACT INFLUENCE OF SOWING TIME ON GROWTH, PRODUCTIVITY AND OTHER YIELD CHARACTERSOF PEANUT CULTIVARS IN THE ALTA PAULISTA REGION, STATE OF SAO PAULO, BRAZIL Field experiments were carried out during the crop growing seasons of 1989/90 and1990/91 in Adamantina, State of Sao Paulo, Brazil. The objective was to study the influenceof sowing time on growth, yield and other agronomic yield characters of four peanut culti-vars under the agroecological conditions of the Alta Paulista. The study used a split-plotexperimental design with six randomized blocks. The main plots were sowing times whereasthe subplots were the cultivars IAC-Oira, IAC-Poitara, IAC-Tupa and Tatu. Decrease in drymatter yield, pod number and yield per plant were observed in all cultivars, from the first tothe last sowing date, i.e., from September /October through March, respectively. Theexperimental results were related to the air temperature. The greatest pod yields were achievedwhen peanuts were sowed between late September and October. The cultivars IAC-Oira,IAC-Poitara and IAC-Tupa showed greater pod number and dry matter yield per plant thanthe cv. Tatu.

Altura e época de montoa na cultura do amendoim

Desenvolveram-se experimentos nos anos agricolas 1988/89 e 1989/90, em Adamantina, para estudar, na cultura do amendoim, o efeito de tres alturas, 3, 6 e 9 cm, e duas epocas de amontoa, aos 28/29 e aos 57 dias apos semeadura na populacao de plantas, numero de vagens por planta, producao de vagens e de graos e peso de graos em cem gramas de vagens de amendoim, sobre o que nao se observou influencia da altura da amontoa. A epoca de amontoa influiu na producao de vagens, no numero de vagens por planta e no peso de graos em cem gramas de vagens de amendoim.

Weed control in transplanted lettuce by oxadiazon

A trial was carried out in order to study the performance of oxadiazon on yield of transplanted lettuce. The treatments were: oxadiazon granular formulation at rates of 1.0,1.5 and 2.0 kg/ha applied after transplanting and pre emergence of weeds; oxadiazom emulsifiable concentrate at 1.0 kg/ha applied before and after transplanting both as preemergence of weeds. Two controls were used: one without any control of weeds and another free from weeds 33 days after transplanting. Oxadiazon gave good control of Portulacca oleracea L, Galinsoga parviflora Cav., Amaranthus hibridus L, Digitaria sanguinalis (L.) Scop, and Eleusine indica (L.) Gaertn. up to 51 days after application. Except for oxadiazon emulsifiable formulation, when applied after transplanting, no phototoxicity to lettuce was observed with the herbicide whether applied at preemergence or before transplanting. The treatment with the emulsifiable formulation showed severe reduction on number and yield of harvested lettuce.

Comportamento do cafeeiro Apoatã em consórcio com culturas anuais

BEHAVIOR OF COFFEE INTERCROPPED WITH ANNUAL CROPS This study was conducted in Adamantina, region of Alta Paulista, Sao Paulo State, Brazil, from 1989 to 1993. Yield of Apoata coffee (Coffea canephora Pierre ex Froehner) was evaluated during four years of intercropping with five plant species: IAC 20 - cotton (Gossypium hirsutum L.); cv. Tatu - peanut (Arachis hypogaea L.); IAC 165 - rice (Oryza sativa L.); cv. Guarani - castor bean (Ricinus communis L.) and IAC 100-B - corn (Zea mays L.). The crops were seeded 50 cm apart from coffee canopy. The treatments were arranged in randomized complete block design with five replications. Yield was significantly decreased when coffee was intercropped with castor bean, corn, cotton and peanut, but height and diameter of orthotropic branches were not affected. Linear correlation analysis showed that coffee yield was inversely correlated with the dry biomass of the intercrops.

EFEITOS DA LARGURA DA FAIXA DE CAPINA NA CULTURA DA MAMONA

Three experiments were carried out in Adamantina at the Experimental Station of Agronomy of Alta Paulista, Instituto Agronomico (IAC), State of Sao Paulo, Brazil, on a Dark Red Latosol during 1989-1992, in order to study the effects of different row widths covered by weeds on the yield, height and number of racemes of IAC-80 castor bean cultivar. Hoed rows of 0.0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 m wide were studied. An extra treatment had the entire plot covered with weeds mantained at 0.3 m height. The row space used was 3.0 x 1.0 m and the plots were 9.0 x 5.0 m. The experiment was set in a randomized complete block design with four replications. Hoeing row width of 1.0 m or less reduced raceme emission, plant height and seed yields.

Utilização do etefom e do tidiazurom na desfolha do algodoeiro e na deiscência de seus frutos

The defoliation and fruit dehiscence of cotton plants were evaluated by applications of Ethephon (rates: 0.96, 1.44 and 1.92kg/ha). Thidiazuron (0.075kg/ha) and the mixture of both Ethephon plus Thidiazuron (0.48 + 0.05, 0.96 + 0.05, and 1.44 + 0.05kg/ha, respectively). The mixture of the products was done in the sprayer tank. Observations of the cotton plants were carried out at seven and fourteen days after application of the products. Except for the application of Ethephon at the rate of 0.96kg/ha, it was observed that the three treatments were effective in promoting cotton defoliation. It was also verified that Ethephon at the rates of 1.44kg/ha accelerated fruit dehiscence while Thidiazuron did not. Antagonic action of the products was observed when applied in mixture. The isolated application of the products or the mixture had no effect on cotton yield.