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There is evidence that the purple nutsedge (Cyperus rotundus L.) aqueous extract can induce the plants rooting due to the high auxin concentrations. This study aimed to evaluate the effect of application seasons and concentrations of purple nutsedge aqueous extract application on the growth and production of carrot, cultivar Brasília. The experimental design was in randomized blocks, in a 2 x 5 factorial scheme in two seasons of the extract application (25 and 50 days after sowing) and five concentrations of (0%, 10%, 20%, 30% and 40%) with four replicates. Harvesting was carried out at 90 days after sowing, being evaluated the following morphological parameters: root diameter (cm); root fresh mass (g plant-1); plant height (cm); aerial part fresh mass (g plant-1); root dry mass (g plant-1); aerial part dry mass (g plant-1); plant dry mass (g plant-1); ratio between root dry mass and aerial part dry mass; root length (cm); commercial productivity (t ha-1); defective root mass (t ha-1); total productivity (t ha-1); commercial yield (roots kg-1); and root classification by length. The extract application at 50th day was more efficient for the root diameter (3.37 cm); fresh root mass (120.7 g plant-1); root length (15.4 cm); commercial productivity (68.2 t ha-1); total productivity (73.6 t ha-1); and commercial roots (8.8 roots kg-1). Root classification by length showed a higher percentage in the 14 cm classification range. The parameters did not present significant differences in both seasons, at 25th and 50th days, respectively, for root dry mass (12.0 and 12.8 g plant-1), ratio between dry mass of roots and aerial part (1.66 and 1.57), and defective root mass (1.3 and 1.5 t ha-1). [ABSTRACT FROM AUTHOR]

The propagation of the jatoba (Hymenaea courbaril L.) by seeds is highly promising in the recovery of degraded areas. Thus, the present research aimed to compare methods for jatoba plant seeds dormancy overcoming and to evaluate the development of seedlings of this species in alternative substrates. In the first experiment, in screened nursery, a completely randomized design was used, with four replications and seven seed treatments: scarification with sandpaper (SS), SS and immersion in water for 24 h, SS and immersion in water for 48 h, intact seed, seed immersed in water for 48 h and seed immersed in water for 96 h. The seedlings that emergency were counted every other days, from 13 to 51 days after sowing, quantifying the emergence percentage, the emergence speed index and the emergence average time. The second experiment, in greenhouse, was composed of three replicates, in randomized blocks, being seven substrates were used: commercial substrate (CS); 40% SC + 60% forest humus (FH); 40% SC + 60% charcoal rice husk (CRH); 40% SC + 60% bovine manure (BM); 40% CRH + 60% BM; 40% CRH + 60% FH; e 40% FH + 60% BM. At 50, 70 and 120 days after sowing were evaluated the parameters: seedling height, leafs number, stem diameter, fresh matter and dry matter of aerial part and roots, and leaf area. At 120 DAS, the chlorophyll index was also evaluated. The scarification with sandpaper and immersion of seeds in water for 24 hours presented a greater emergence (96.4% and IVE = 0.697). The mixture containing 40% FH and 60% BM resulted seedlings with a larger leaf area, chlorophyll index and roots and aerial part dry matter, at 120 days after sowing. [ABSTRACT FROM AUTHOR]

The Mato Grosso northeast, in Brazil, is characterized by presenting reference evapotranspiration above 4.0 mm day-1. This high water demand indicates that the frequency of irrigation and the amount of N supplied to the radish crop can influence water saving, fertilizer and quality root production. Thus, the aim this paper was to evaluate the radish production as a function of the irrigation daily frequency and nitrogen rates in coverage. Seeds of the 'Crimson Gigante' radish cultivar were used, and the experiment was conducted in a medium texture Argisol, increasing the base saturation to 70%. The experimental design was a randomized complete block, with four replications in split plots, in the 2 x 6 scheme, being two irrigation frequencies in the plots and six nitrogen fertilization rates (0, 25, 50, 75, 100 and 125 kg ha-1 of N) in the subplots. The frequencies consisted of irrigation once a day (in total time, in the morning, 6:15 - 7:15 am); and twice a day (50% of the time in each period, in the morning, and in the afternoon, 5:30 - 6:30 p.m.), respectively, restituting the crop daily evapotranspiration, obtained by weighing lysimeters. The harvest was accomplished at 30 days after 'sowing. The defects roots production (11105.4 kg ha-1) was higher than the commercials roots productivity (1658.2 kg ha-1). The irrigation twice a day (morning and afternoon) and the application of N rates up to 100 kg ha-1 provided greater leaf area, dry matter of roots, aerial part and total plants, but did not provide gain in the production of commercial roots. [ABSTRACT FROM AUTHOR]

Dadas as altas temperaturas na região nordeste de Mato Grosso, a frequência da irrigação e a quantidade de N fornecida à cultura do rabanete são parâmetros de alta relevância, que podem influenciar na economia de água, fertilizantes e produção de raízes de qualidade. Assim, o objetivo deste trabalho foi avaliar a produção de rabanete em função da frequência de irrigação e doses de nitrogênio em cobertura. Foram utilizadas sementes da cultivar Crimson Gigante, sendo o experimento conduzido num Argissolo de textura média, elevando a saturação de bases a 70%. O delineamento foi o de blocos ao acaso, com quatro repetições em parcelas subdivididas, no esquema 2 x 6, sendo duas frequências de irrigação nas parcelas e seis doses de adubação nitrogenada em cobertura (0, 25, 50, 75, 100 e 125 kg ha-1 de N) nas subparcelas. As frequências consistiram em irrigação uma vez por dia (em tempo total, de manhã, 06:15 - 07:15 h); e duas vezes por dia (50% do tempo em cada período, de manhã, e à tarde, das 17:30 - 18:30 h), repondo a evapotranspiração diária da cultura, obtida através de lisímetros de pesagem. A colheita foi realizada aos 30 dias após a semeadura. O aumento das doses de N propiciou maior área foliar, matéria seca de raízes, da parte aérea e total das plantas. Em média, a massa de raízes com defeitos (11.105,4 kg ha-1) foi superior à de raízes comerciais (1.658,2 kg ha-1). A irrigação duas vezes ao dia (manhã e tarde) proporcionou melhor resposta da cultura do rabanete.

Há evidências de que o extrato aquoso de tiririca (Cyperus rotundus L.) possa induzir o enraizamento de plantas, por apresentar elevadas concentrações de auxinas. O objetivo deste trabalho foi avaliar o efeito de épocas de aplicação e concentrações de extrato aquoso de tiririca no desenvolvimento e produção da cenoura, cultivar Brasília. O delineamento experimental foi em blocos casualizados, em esquema fatorial 2 x 5, sendo duas épocas de aplicação do extrato (25 e 50 dias após semeadura) e cinco concentrações de extrato de tiririca (0%, 10%, 20%, 30% e 40% v/v), com 4 repetições. A colheita foi realizada aos 90 dias após a semeadura, sendo avaliados os seguintes parâmetros morfológicos: diâmetro de raízes (cm); altura de plantas (cm); massa fresca de raízes e da parte aérea (g planta-1); massa seca de raízes e da parte aérea (g planta-1); massa seca total (g planta-1); razão das massas seca de raízes e parte aérea; comprimento de raízes (cm); produtividade comercial (t ha-1); massa de raízes com defeito (t ha-1); produtividade total (t ha-1); rendimento comercial (raízes kg-1); e classificação das raízes por comprimento. A aplicação do extrato aos 50 dias mostrou-se mais eficiente ao diâmetro de raiz (3,37 cm), massa fresca de raízes (120,7 g planta-1), comprimento de raízes (15,4 cm), produtividade comercial (68,2 t ha-1), produtividade total (73,6 t ha-1) e raízes comerciais (8,8 raízes kg-1). A classificação das raízes apresentou maior porcentagem na classe de 14 cm. Os parâmetros massa seca de raiz (12,0 e 12,8 g planta-1), razão de massa seca de raízes e parte aérea (1,66 e 1,57) e massa de raízes com defeito (1,3 e 1,5 t ha-1), aos 25 e 50 dias, respectivamente, foram semelhantes em ambas as épocas.