A staging system for development of gladiola (Gladiolus × grandiflorus) that relies on simple, visual, non-destructive criteria is proposed. Four field trials were conducted during the spring 2010, autumn/winter 2011 and winter 2011 at Santa Maria, RS, Brazil, with different gladiola cultivars, in order to observe the developmental stages of the above-ground parts and their dry matter. The developmental cycle, which starts at dormant corm and ends with plant senescence, is divided into four developmental phases: dormancy phase, sprouting phase (from filiform roots appearance to sheaths appearance), vegetative phase (from emergence of the first leaf tip to emergence of the final leaf tip on the stem) and reproductive phase (from heading to plant senescence). The developmental stages that were identified during the dormancy phase and during the sprouting phases are coded as S stages: S0 = dormant corm, S1 = appearance of roots, S2.1 = first sheath, S2.2 = second sheath and S2.3 = third sheath. Vegetative phase is coded as V stages: VE = emergence of the sheaths above ground, V1 = first leaf, V2 = second leaf, Vn = nth leaf and VF = flag leaf. Leaf tip is the marker for V1-VF. The developmental stages during the reproductive phases are coded as R stages: R1 = heading, R2 = blooming, R3 = onset of flowering, R4 = end of anthesis, R5 = end of florets senescence and R6 = plant senescence (leaves and floret axis are brown). Sub-stages have also been assigned between R1 and R2 and between R3 and R4. Illustrations (photographs) of each developmental stage taken from field pot-grown plants are provided and the proposed scale was tested with field observations. These criteria are straight forward and allow for quick determination of development stage. This system can be used by both farmers and for experimental trials.

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Resumo -O objetivo deste trabalho foi determinar as épocas de cultivo, em ambiente subtropical, em que é possível produzir hastes de gladíolo (Gladiolus x grandiflorus) que atendam aos padrões comerciais quantitativos do mercado nacional de flores de corte. Dois experimentos de campo foram realizados, um de agosto de 2011 a julho de 2012 e outro de agosto de 2012 a julho de 2013, com três cultivares do gladíolo e 12 datas de plantio para cada experimento. O comprimento total da haste, o comprimento do pendão e o diâmetro da haste foram avaliados quando as hastes estavam em ponto de colheita, ou seja, quando a cor das pétalas apareceu nos três primeiros floretes na base da haste. Os melhores meses para a produção de hastes de gladíolo são julho, agosto, setembro, fevereiro, março e abril, embora em nenhuma das datas de plantio tenham sido produzidas hastes com parâmetros quantitativos abaixo do padrão mínimo (exceto em períodos com geada, durante o espigamento).Termos de indexação: Gladiolus x grandiflorus, época de cultivo, floricultura, padrão comercial, qualidade.

Cassava [Manihot esculenta (L.) Crantz] plays an important role as staple food in the tropics. The GUMCAS model is a process-based dynamic simulation model for cassava that has been adapted to the Cropping System Model (CSM) framework of DSSAT (DSSAT-CSM). The objective of this study was to calibrate and evaluate the original GUMCAS model, a modified version of the GUMCAS model, and the current cassava model in DSSAT under potential conditions in the subtropical environment of Rio Grande do Sul State, Brazil. The modified original GUMCAS model consisted of three modifications in the code: we included a third independent "clock" in the cassava development for the onset of starch accumulation, we replaced the rate of leaf appearance submodel with the Wang and Engel model, and we modified the leaf senescence submodel. Model calibration was with a field experiment for cultivar Fepagro-RS 13 during the 2011/2012 growing season in Santa Maria, Brazil. Independent data from 16 experiments conducted at four sites in Rio Grande do Sul State were used for testing the performance of the three versions of the cassava model. The original GUMCAS model had the poorest performance, and the modified GUMCAS model slightly improved the predictions of stem and storage root yield compared with the current DSSAT cassava model. The modified GUMCAS model greatly improved the predictions of developmental stages, leaf development, and leaf area growth dynamics compared with the current DSSAT cassava model. Results from this study contribute to our understanding on how a cassava system functions in the subtropics.

IIIDesenvolvimento vegetativo e reprodutivo em gladíolo Vegetative 'Peter Pears', 'Sunset', 'T704', 'Traderhorn', 'Rose Supreme' and 'Jester', and another