Maria Isabel da Silva Aude

MANEJO DO PALHIÇO DA CANA-DE-AÇÚCAR. 1. EFEITO NA PRODUÇÃO DE COLMOS INDUSTRIALIZÁVEIS E OUTRAS CARACTERÍSTICAS AGRONÔNICAS

A field experiment was conducted at Federal University of Santa Maria, RS, Brazil, with objective to study different methods of handling sugarcane trash and its effects on productivity and other agronomic characteristics. It was tested five treatments of sugarcane trash, in four consecutive harvests. Treatments of burning the sugarcane plant before harvest, harvesting and burning the remaining trash and remove the trash from plots behaved the same way in relation to industrialized culms production. Aligning it in alternate rows and triturate and redistribute in the field showed less productivity. In relation to brix % juice, it could be suggest any one method of handling the trash studied, because all them presented brix % juice above 18%. The production of green matter from the upper immature part of the stalk, diameter, mean weight of the culm and internode number was not affected by methods of handling the trash.

ESTÁDIOS DE DESENVOLVIMENTO DA CANA-DE-AÇÚCAR E SUAS RELAÇÕES COM A PRODUTIVIDADE

A finalidade principal da cana-de-acucar e a producao de sacarose, que depende das condicoes ambientais durante o crescimento e do periodo de concentracao de acucar. Apresenta quatro estadios de desenvolvimento que sao afetados por diversos fatores. A brotacao das gemas e afetada pela dominância apical, estado nutricional do tolete, posicao da gema no colmo, posicao da gema no sulco, tratamento para prevenir doencas, cultivares e fatores climaticos. Logo apos a brotacao das gemas inicia o perfilhamento que depende principalmente dos fatores climaticos, adubacao, cultivares e praticas culturais. Do final do perfilhamento ao inicio da acumulacao de acucar depende basicamente da idade fisiologica da planta, dos fatores climaticos e nutricionais. Ao completar o ciclo paralisa o crescimento e inicia a concentracao de acucar ate atingir valores aceitaveis pela industria. Em temperaturas maiores que 18°C, a cana podera continuar no estadio de crescimento ate que outro fator determina a paralisacao do crescimento e subsequente acumulo de acucar. Deficiencia hidrica tambem paralisa o crescimento e favorece a concentracao de acucar.

DENSIDADE DE SEMEADURA E PRODUTIVIDADE DO PORONGO

Two experiments were conducted in order to study the best plant densities of Lagenaria siceraria (Mol.) Standi, known as bottle gourd and used as a tea container, named cuia. The Experiment 1 was conducted in Santa Maria - RS, during 1987-88, and the number of hills per hectare were 2.222; 2.500; 2.666; 3.333 and 4.444. During 1988-89 the Experiment 2 was located in Restinga Seca - RS, 1.111; 2.222; 3.333; 4.444; 5.555 and 6.666 hills per hectare were tested. Both years were evaluated the number of fruits/ha and fruits/hill. The number of knots per plant, the thickness of the hull and the external volume of fruit, on the second year only. The results showed that productivity was not related to the plant densities studied, but the best results were obtained with densities varying of 3.333 to 5.555 hills per hectare. The number of fruits per hill, knots per plant and hull thickness decreased at higher plant densities. At lower densities productivity was compensated by the increasing in number of fruits per hill. Increasings in plant population resulted in lower external volume of the fruits, also.

ÍNDICE DE ÁREA FOLIAR DE TRÊS CULTIVARES DE ARROZ IRRIGADO

SUMMARY An experiment was conducted on a ALBAQUALF soil of the Vacacai Mapping Unit located on the Campus of the Universidade Federal de Santa Maria during the 1986/87 growing season. The objective was to observe the conduct of the leaf area index of three irrigated rice varieties (EEA 406, BLUEBELLE and BR-IRGA 409) and with different morphological traits. The experimental design was a randomized block with five replications. Treatments were the three varieties. Variety EEA 406 had the highest values the leaf area and leaf area index (LAI), in all the growth stages, followed by varieties BLUEBELLE and BR-IRGA 409. The leaf size was the component that more affected leaf area and leaf area index, for the three varieties.

ÉPOCA DE PLANTIO E SEUS EFEITOS NA PRODUTIVIDADE E TEOR DE SÓLIDOS SOLÚVEIS NO CALDO DA CANA-DE-AÇUCAR

The experiment was conducted at the Federal University of Santa Maria with the objective of verify the planting date of sugarcane that will lead to increased yield and brix. Were tested two sugarcane varieties (NA 56-79 and IAC 50-1345) in eight planting dates. The planting dates were monthy from August, 15, 1985 to March, 15, 1986. There was not difference between the sugarcane planted in August and September, and between varieties for productivity. In the harvest of plant-cane, the mean productivity was 82,5t/ha, for these two planting dates. Sugarcane planted in August-September had higher productivity when harvest was done 12 months after planting time. Sugarcane planted in January/1986 and harvested 19 months later had a higher production of industrialized culms (167.2ton.ha) and was different from the ones planted in October/85, January, February and March/86. In planting time of January, February and March the productivity was higher when the plant-cane was harvested 18 months later. The average Brix for the August and September plantings was 19,8% independent of cultivar. The highest Brix average was observed in sugarcanes planted in February (20,1%) which was different from other planting dates.

Comportamento de genotipos de arroz irrigado em Santa Maria - RS

Recommended cultivars in use at Depressao Central region of Rio Grande do Sul State and inbreed lines were evaluated each year from 1984 to 1995. The objective was to compare the performance of genotypes aiming to achieve a regionalized recommendation of cultivara.

DOSES E ÉPOCAS DE APLICAÇÃO DO CLORETO DE CHLORMEQUAT EM TRIGO: Resposta da cv. CEP-19

An experiment was conducted aiming to evaluate the effect of Chlormequat Chloride (CCC) doses and application time on the wheat cultivar CEP-19. It was carried out during 1990, at the Federal University of Santa Maria on a Distrophic Read Yellow Podzolic soil. The doses applied were zero, 200, 300, 400 and 500g/ha having as source the product Tuval (10% a. i.) and 1000g/ha of the commercial product Cycocel (50% ai.) applied at growth stage 3 (tillering), 6 (first visible nod) and 8 (booting) and doses fractioning. Grain yield and harvest index increased linearly with CCC applied at tillering stage. Plant height decreased with CCC applied mainly at growth stages 3 and 6. Dose parceling did not affect plant characteristics studied or grain yields.

Acúmulo de matéria seca e duração do período de enchimento de grãos do triticale

The experiment aimed to determine the rate and duration of grain filling period of triticale in Santa Maria region -RS. Five cultivars (BR l, BR 2, CEP 15. CEP 18 and IAPAR 23) were evaluated in a randomized complete block design in 1988 and 1989. The duration from anthesis to physiological maturity was 45 days, while the duration of the life cycle from seeding to physiological maturity was 156 days, corresponding to 676 and 1637 accumulated growing degree days, respectivelly. The rate of dry matter accumulation m the grain of triticale was 0.694mg/day, and the mean dry weight estimated at physiological maturity was 31.3mg. The cultivars were different in terms of the rate of dry matter accumulation, wich is possible to suggest the use of this trait to cultivar recommendation in regions where normally occur high temperatures in the end of the filling period. The mean grain weight was associated with the rate of dry matter accumutation and not wich the grain filling period.

EFEITO ADVERSO DO VENTO EM ARROZ IRRIGADO

Signs of injury in irrigated rice panicles caused by high-speed north wind associated to high temperature and low relative umidity observed in the region of Santa Maria - RS are described. It is presented the methodology used to confirm what was observed in the plants. The loss depends on the plant stage of development and it appears in the panicles or in the sterility of spickelets.