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The objective of this study was to evaluate methods of breaking dormancy in Sesbania punicea seeds for seedling production. The treatments used were control, manual scarification for 40 s, manual scarification for 60 s, thermal scarification and chemical scarification. After the treatments were carried out, the seeds were placed to germinate at 25 ºC and a 16-hour photoperiod for 14 days. The germination percentage, average germination time, germination speed index, percentage of normal seedling formation, shoot length, root system length and percentage of hard seeds were evaluated. A completely randomized design with four replications of 25 seeds was used. The data were submitted to ANOVA and the means compared by Tukey 5%. There was a difference for all the analyzes evaluated, except for the length of the aerial part. The treatment with manual scarification 60 s had superior results, being indicated for overcoming dormancy of seeds of S. punicea.

The objective of the study was to evaluate the biometry of fruits and seeds of S. punicea in order to determine the point of collection for production of seedlings of the species. The fruits of S. punicea were collected from plants in situ in Barra do Ribeiro, RS. In the laboratory, they were separated by staining in: stage 1, 2 and 3. Fruits and seeds were measured with digital caliper (mm), counting the number of seeds and locules. At each stage water content, seed dry matter and germination test were evaluated. For this last one, four replications of 25 seeds were placed in germination chamber during 16 days, photoperiod of 12 hours and temperature of 25oC. The variables analyzed were germination, germination speed index, average germination time, percentage of normal and abnormal seedlings, and hard seeds. It was observed that in stage 2 the seeds have larger dimensions, a higher percentage of germination and formation of normal seedlings, and a higher rate of germination speed. It is concluded that fruits must be harvested at stage 2 of maturation, as seeds have the highest rates of germination and normal seedlings, as well as the lowest rates of insect damage.

O objetivo do trabalho foi avaliar o efeito da concentração de ácido indol-3-butírico (AIB) e substratos no enraizamento de estacas apicais de Angelonia integerrima. Utilizou-se AIB em pó, nas concentrações de 0, 500, 1000, 2000 e 4000 mg kg-1 e dois substratos: casca de arroz carbonizada (CAC) e substrato comercial a base de turfa de Sphagnum. Avaliou-se: número de estacas enraizadas, comprimento da parte aérea e do sistema radicular, número de folhas novas, volume do sistema radicular, formação de calo na base da estaca, massa seca da parte aérea e do sistema radicular. O delineamento experimental foi inteiramente casualizado, em esquema fatorial (5 concentrações de AIB x 2 substratos). Não houve interação entre as concentrações de AIB e substratos, somente houve diferença para o fator substrato. As estacas apresentaram enraizamento médio de 79%, com formação de calo em 59,4%. O substrato CAC promoveu maior comprimento da parte aérea e maior número de folhas novas. O substrato comercial proporcionou maior volume médio de raiz, maior comprimento de raiz e maior incremento de massa seca radicular. No enraizamento por estaquia de A. integerrima não é necessário usar AIb e pode-se utilizar o substrato comercial à base de turfa ou a CAC. The objective of this study was to evaluate the effect of the concentration of indole-3-butyric acid (IBA) and substrates in the rooting of apical cuttings of Angelonia integerrima. Powder IBA was used at the concentrations 0, 500, 1,000, 2,000 and 4,000 mg kg-1, and two substrates containing carbonized rice husks (CRH) and commercial substrate based on Sphagnum peat were used. The number of rooted cuttings, shoot length, root system length, number of new leaves, root system volume, callus formation at the cutting base, and shoot and root dry matter were evaluated. The experimental design was completely randomized with a factorial design (5 IBA concentrations x 2 substrates). There were no interactions between the concentrations of IBA and the substrates. There was a difference only for the factor substrate. The cuttings presented an average rooting of 79%, with callus formation in 59.4% of them. The CRH substrate presented the highest shoot length and the highest number of new leaves. The commercial substrate resulted in a high average root volume, a large root length and a great increase in root dry matter. In the rooting by cutting of A. integerrima is not necessary to use IBA and the commercial substratum based on peat or CRH can be used.

Calceolaria x herbeohybrida Voss (pocketbook plant, calceolaria) is an herbaceous perennial and floriferous species that can be grown in pots or beds. Nitrogen is usually the most required nutrient, being necessary to conduct studies in order to provide useful information for agronomic practices. Thus, this study aimed to evaluate nitrogen doses in the growth of Calceolaria x herbeohybrida in pots. Initially, assorted and pelleted calceolaria seeds were sow in multicellular trays containing a commercial substrate based on peat and kept in a floating irrigation system in a protected environment. At the greenhouse, seedlings with four true leaves were transplanted into 1 L pots containing the same substrate and a drip irrigation system. The treatments consisted of different nitrogen doses (0.0, 0.5, 1.0, 2.0 or 4.0 g of N L-1) applied weekly using ammonium nitrate as source. Fertilization with P and K was also done, and all treatments received de same dose. At the end of the experimental period, shoot length, leaf area, shoot and root dry matter, number of buds and flowers, chlorophyll a, b and total chlorophyll were evaluated. The experimental design was completely randomized with four replications and five plants per plot. The data were treated with ANOVA and the means were treated with regression analysis using the SigmaPlot 11.0 software. There was no survival of plants at the highest N dose (4.0 g L-1). Shoot length showed a quadratic behavior, with a maximum point at 1.25 g L-1, where plants reached 13.3 cm. There was a similar behavior for the variable leaf area, with the highest point at 1.24 g L-1. Shoot dry mass presented the maximum point at a dose of 1.20 g L-1, resulting in 4.21 g of dry matter. Regarding root dry matter, no equation could be adjusted. For the variable number of buds and flowers, the highest point was at a dose of 1.20 g L-1, with 35.86 buds and flowers per plant. For chlorophyll a, b and total chlorophyll, the maximum point was at 1.5 g L-1. The ideal nitrogen dose is between 1.2 and 1.5 g L-1 for most variables.