Marie Yamamoto Reghin

Stimulate Mo e proteção com Tecido "Não Tecido" no pré-enraizamento de mudas de mandioquinha-salsa

It was evaluated the effect of doses of Stimulate Mo, a product with growth regulators on the sprouting and pre rooting of Peruvian carrot explants, cultivar Amarela Comum, associated with and without floating rowcover of polypropylene. The following doses were tested: 1) 0 (control without treatment); 2) 2.5 ml/ L; 3) 5.0 ml/ L; 4) 7.5 ml/ L and 5) 10.0 ml/ L. The explants were removed from the cornels, selected by size (10-15g), cut in bezel (1.5-2.0 cm of length) and treated by immersion in sodium hypocloride 10% during three minutes. Afterwards the explants were treated in different dose of Stimulate Mo during 30 minutes and stored during five days in a shaded place. After planting the floating rowcover of polypropylene had been set, it was evaluated the percentage of explants with sprouting, number and length of leaves and number and length of roots. It was not observed significative effect of interaction between floating rowcover and doses of Stimulate Mo. The protection by floating rowcover was superior in all of the characteristics observed, promoting the development of uniforms and vigorous explants and early pre-rooting at 36 days after planting. The product Stimulate Mo was efficient to increase number and root length confirming its utility as a rooting stimulator.

Use of non woven polypropylene protection under lettuce crop during winter season in Ponta Grossa, Brazil

A field experiment was carried out in Capao da Onca School Farm, at the Universidade Estadual de Ponta Grossa in Brazil. The effect of the protection of an spunbonded polypropylene non woven fabric on the development, quality and yield of three lettuce cultivars, transplanted during the winter of 1998 was studied. The experimental design was of complete randomized blocks, displayed in a factorial scheme 3x2 (cultivars x crop system), with five replications. The cultivars were Taina, Elisa and Veronica growing under non woven polypropylene protection (PP) and environmental conditions (EC). Greater head fresh weight was observed on woven protected plants. Increased leaf area index (LAI) was observed for Taina and Veronica, with consequent increase of biomass in row cover plants. Elisa showed etiolate leafs, that lost rapidly the turgidity after harvesting. It is possible that the radiation levels under PP were bellow of the saturated photosynthetic point for cv. Elisa. The use the non woven protection for cv. Veronica and cv. Taina, during winter season of Ponta Grossas region is recommended, due to the fact that these plants presented heads with excellent quality and commercial weight.

Respostas do feijão-vagem cultivado sob proteção com agrotêxtil em duas densidades de plantas

The effect of nonwowen polypropylene protection condition and plant density on the yield of two cultivars of snap beans was evaluated. The current work was carried out at an experimental area of the Universidade Estadual de Ponta Grossa, Parana State, Brazil. The experimental design was a completely randomized in split plots 2x2x2 (cultivars x protection x plant density), with four replications. The cultivars Turmalina and Coralina were sown in March (autumn), 2000, in two plant densities (6.6 and 3.3 pl m-1) under nonwowen protection (PP) and natural environment (AN). Early yield, total yield, number and weight of pods were evaluated. The air (Tar) and soil temperature amplitudes (Ts) under PP and AN were also evaluated. Nonwoven protection and plant density did not influence the early yield. However, the use of nonwoven protection increased yield of Turmalina as a result of higher number of pods per plant, compared with AN. There was no difference between PP and AN on yield of Coralina. The plant density did not influence yield response of Turmalina. On the other hand, Coralina was more productive when cultivated under plant density of 3,3 pl m-1, when compared to 6,6 pl m-1. Coralina was more productive than Turmalina when cultivated under 3,3 pl m-1, however without differences between cultivars under 6,6 pl m-1. Air and soil temperature were higher under PP compared to AN, during the whole cycle of the culture, with medium differences between PP and AN of 2,63 and 1,97oC, respectively for Tar and Ts. The difference between PP and AN, for Tar and Ts, was higher at the beginning of plant growing and decreased with the development of snap bean.

Produção de repolho branco chinês (pak choi) sob proteção com "não tecido" de polipropileno

Yield of chinese white cabbage (pak choi) (jBrassica campestris var. chinensis), hybrids Canton and Chouyou were evaluated under 17 and 25 g/m-2 of non woven white polypropylene in winter, compared to open field at Campos Gerais, Brazil. Sowing date was in March, 11th and plants were transplanted to the field at the stage of 4 - 5 leaves in june, 23rd. A randomized block experimental design was used with five replications in a factorial scheme 3x2. Non woven polypropylene was used as row cover after transplanting. At the harvest according to plant maturity, the number of leaves, plant height, diameter of plant basis, plant fresh weight and dry matter were evaluated. The percentage of plants with bolting was evaluated at 51 days after transplanting. Under field conditions, plants from hybrid Canton were damaged showing the leaf extremity entirely nipped by frost but the hybrid Chouyou was resistant. Non woven protected the plants against frost and promoted a faster plant development and early crop at 38 days after transplanting with the use of a grid of 25 g/m-2, at 42 days with 17 g/m-2. Under open field conditions harvest was made only after 46 days. The superior quality under non woven when compared to open field conditions was observed with the characteristics of higher plant fresh weight, dry matter of plants, number of leaves, plant height and diameter of plant basis. Between both hybrids taken into account at the current study Canton was more precocious than Chouyou; however Canton initiated bolting at 36 days after transplanting. Non woven with a grid of 25 g/m-2, compared to that one of 17 g/m-2 was superior to hybrid Canton for the characteristic of earliness at the winter season in Campos Gerais, Parana State, Brazil.

Post-emergence weed control in carrot crop.

The presented field trial was conducted in 1995 in Pirai do Sul, Parana State, Brazil, on a sand-clay texture soil, to evaluate the efficiency and selectivity of propaquizafop on carrot crop weed control. The experiment was laid out in a randomized block design with six treatments and four replications, and 5.00 x 1.00 m plots. The treatmens were: propaquizafop (100, 125 and 150 g a.i/ha); fluazifop-p-butil (188 g a.i/ha); control with weeding and control without weeding. The carrot cultivar Nantes Tim Tom was sown on June 15 with plants spaced 0.25 x 0.05 m. The prevalent weeds were Brachiaria plantaginea (capim-papua), Digitaria horizontalis (capim-milha) and Eleusine indica (capim pe-de-galinha). Evaluations were carried out at 15, 30 and 45 days after treatment applications. The herbicide propaquizafop, at doses 100, 125 and 150 g a.i/ha, was efficient in control of capim-papua, capim-milha and capim pe-de-galinha. Weed control using herbicides resulted in the same production when compared to manual control. Production losses due to the presence of weeds was 76.4%. Carrot plants did not show any visual symptoms of damage attributed to herbicide applications.

Flowering induction and seed yield in lettuce with different doses of gibberellic acid

Doses of gibberellic acid (0, 10, 20 and 40 ppm) in three lettuce bolting-resistant cultivars (Marisa, Veronica and Elisa) were tested with the aim to induce flowering and seed yield. The experimental design was a complete randomized block, with four replications in a 4 x 3 factorial scheme. The sowing was done on 27/05/98 and the transplanting on 24/06/98, with the plants at the stage of 4 - 5 leaves. The application was performed only once at the stage of 10-12 leaves, using the product Pro-Gibb (ABBOTT), with 10% of gibberellic acid. The lettuce crop was managed accordingly to the usual recommendation. Seeds were harvested based on the physiological maturity and the harvest ranged from 02/12 to 21/12. There were evaluated the number of days to anthesis, number and height of stem flowering, flowering percentage, seed yield, weight of 1,000 seeds and percentage of seed germination. Flowering earliness was different among cultivars being Elisa the most precocious, regardless of gibberellic acid application and followed by Veronica and Marisa. The effect of doses had statistical significance on cv. Veronica and Marisa, being the highest flovering percentage at the dose of 28 ppm for the cv. Veronica and 35 ppm for Marisa. However, superior seed yield was observed at the dose of 23 ppm in both cultivars. On the other hand seed production from Elisa was significantly superior than from the other two cultivars, being the highest seed production observed on the control, (without application of gibberellic acid). Gibberellic acid increased the flowering percentage, earliness of the anthesis, seed maturation and seed yield, but the response depended on the cultivar; the later or more resistant to bolting the more pronounced were the effects of the gibberellic acid being recommended a dose of 23 ppm.

Avaliação de inseticidas no controle de Myzus persicae (sulz.) (homoptera: aphididae) na cultura da alface

A field trial was carried out at Universidade Estadual de Ponta Grossa, State of Parana, Brazil, in 1999, to evaluate the efficiency of insecticides in controlling Myzus persicae (Sulz) on lettuce cv. Veronica. The experimental design was of completely randomized blocks with six treatments and four replications. The treatments consisted of thiamethoxam (50; 75 and 100 g i.a/ha) imidacloprid (140 g i.a/ha); pymetrozine (150 g i.a/ha) and control. The treatments were applied to seedlings grown in polyestyrene trays one day before the transplanting. The fitotoxicity, the number of aphids/plant, the percentage of plants with aphids and the efficiency of the insecticides were evaluated. Thiamethoxan at doses of 50; 75 and 100 g i.a/ha was efficient to control M. persicae from transplanting till 43 days after showing equal or higher efficiency than 98.6%, similar to imidacloprid. The pymetrozine was efficient to control M. persicae until 21 days after transplanting. Effects of fitotoxicity on lettuce plants were not observed. Higher fresh weight was observed in treated plants in comparison to the one of the control.

Ocorrência de doenças do pak choi no estado do Paraná, Brasil

Pak choi (Brassica chinensis) is a vegetable crop that was recently introduced in Brazil from Asia by seed importer companies. In the state of Parana this crop is becoming increasingly important in the Curitiba area, mainly under protected cultivation. A survey of diseases in this crop was performed during the growing period of 1999/2000, in the School Farm Capao da Onca of the Ponta Grossa State University. Materials collected were analyzed at the plant pathology laboratories of this university and at the University of Sao Paulo, at Piracicaba. In the summer crop, the most prevalent diseases were: Alternaria spot (Alternaria sp.), soft rot (Erwinia sp.) and white rust (Albugo candida). In the fall, there was a low incidence of Alternaria spot and soft rot and white rust did not occur at all.

Evaluation of herbicides on post-emergent weed control in potato crops.

O experimento foi instalado na Fazenda Escola da UEPG, Ponta Grossa-PR, em solo Latossolo Vermelho Escuro de textura media argilosa, tendo como objetivo avaliar a eficiencia e a seletividade do herbicida propaquizafop no controle pos-emergente de plantas daninhas na cultura da batata. O delineamento experimental foi de blocos ao acaso com seis tratamentos: propaquizafop (100, 125 e 150 g i.a./ha); fluazifop-p-butil (188 g i.a./ha); testemunha capinada e testemunha sem capina, em quatro repeticoes. O plantio foi realizado em 26 de outubro com a cultivar Elvira, usando-se o espacamento de 0,70 x 0,35 m. As plantas daninhas presentes foram: Brachiaria plantaginea (capim-papua), Digitaria horizontalis (capim-milha) e Eleusine indica (capim pe-de-galinha). As avaliacoes foram efetuadas aos 15, 30 e 45 dias apos a aplicacao dos tratamento. Observou-se que a aplicacao de herbicidas pos-emergentes apos a amontoa, permite controle adequado de plantas daninhas desde a emergencia ate a colheita; o herbicida propaquizafop mostrou-se eficiente no controle sobre capim-papua e capim pe-de-galinha nas doses de 100, 125 e 150 g i.a./ha e sobre capim-milha nas doses de 125 e 150 g i.a./ha. As perdas na producao causadas pela competicao com plantas daninha foram da ordem de 57,4 %. Nao foram observados efeitos fitotoxicos nas plantas de batata que pudessem ser atribuidos aos tratamentos aplicados.

Controle de plantas daninhas na cultura da batata

O experimento foi conduzido na Fazenda Escola da UEPG, em Ponta Grossa-PR, em Latossolo Vermelho Escuro de textura media argilosa, com o objetivo de verificar a praticabilidade e a eficiencia agronomica dos herbicidas metolachlor e metribuzin + metolachlor no controle de plantas daninhas na cultura da batata. O delineamento experimental foi de blocos ao acaso com nove tratamentos e quatro repeticoes, quais sejam: metolachlor (1,92; 2,88 e 3,84 kg i.a./ha); metribuzin + metolachlor (0,24 + 1,68; 0,36 + 2,52 e 0,48 + 3,36 kg i.a./ha); metribuzin (0,48 kg i.a./ha); testemunha capinada e testemunha sem capina. O plantio foi realizado em outubro/95 utilizando-se a cultivar Elvira, no espacamento 0,70 x 0,35 m. As plantas daninhas predominantes foram Brachiaria plantaginea (capim-papua), Digitaria horizontalis (capim-milha) e Galinsoga parviflora (fazendeiro). As avaliacoes foram efetuadas aos 15, 30 e 45 dias apos a aplicacao dos tratamentos onde verificou-se que foram eficientes os seguintes herbicidas: metolachlor no controle sobre capim-papua e capim-milha nas doses de 2,88 e 3,84 kg i.a./ha; a mistura metribuzin + metolachlor no controle sobre capim-papua e capim-milha nas doses 0,36 + 2,52 e 0,48 + 3,36 kg i.a./ha; metolachlor (1,92; 2,88 e 3,84 kg i.a./ha) e metribuzin + metolachlor (0,24 + 1,68; 0,36 + 2,52 e 0,48 + 3,36 kg i.a./ha) no controle sobre fazendeiro. Nao foram observados efeitos fitotoxicos dos produtos sobre as plantas de batata.