Adeliano Cargnin

Enchimento de sementes em linhas quase-isogênicas de trigo com presença e ausência do caráter "stay-green"

The stay-green trait has been used as an alternative to reduce the senescence in wheat, resulting in an effective functional increase of the leaf area, and an increase in the rate and duration of the seed filling period. The objective of this work was to analyse the rate of dry matter accumulation and the duration of the seed filling period of near-isogenic lines of wheat differentiated by the presence and absence of the stay-green trait. The experiment was conducted in the Experimental Center of Palma, in Pelotas, State of Rio Grande do Sul, in Brazil. Four near-isogenic lines were used: F6-SG and F6-SZ in the year of 2000 and F7-SG and F7-SZ in the year 2001, with five replications. The stay-green trait allowed a higher deposition of plant reserves in the seed, during the phase close to the point of physiological maturity. The duration of the seed filling period in the evaluated genotypes was associated to the dry matter accumulation in the seed. Promoting a larger weight is a trait responsible for the selection of genotypes with high rates of seed filling.

Efeitos de regulador de crescimento, controle de doenças e densidade de semeadura na qualidade industrial de grãos de arroz

This study was carried out to evaluate the application effects of the growth regulator ethephon on the flowering and maturation uniformity and disease control at the end of the crop cycle. The effect of the fungicide tebuconazole,

Expressão do fenótipo em populações segregantes de aveia conduzidas em diferentes ambientes

Selection on the phenotype basis can be affected by environmental factors; forcing the plant-breeder to isolate genetic and environmental factors. The objective of this work was to evaluate the yield components of oat segregant populations subjected to different methods. Eight populations were planted in random block design with two replicates, according to three different models: spaced plant, full line and hill. Panicles with weight higher than mean plus one standard deviation were selected and measured for grain weight and grain number per panicle. Results showed a significant interaction between populations and environmental factors. Heritability was high, excepted for grain number/panicle on the full line models. Panicle weight can be an efficient trait to select genotypes in order to order increase grain yield.

Métodos de semeadura na condução de populações segregantes de aveia e suas interações com o ambiente de seleção

Phenotype-based selection can be influenced by environmental factors. Plants breeders need to use selection methods to separate genetic from environmental effects. The goal of this study was to test the efficacy of indirect selection to increase oat (Avena sativa L.) grain yield under different sowing systems. Eight oat segregant populations were selected for panicle weight under three different sowing methods (hill, spaced plant, full line), during 2000 and 2001 growing seasons, The development of superior genotypes required evaluation in distinct years mainly to minimize environment effects. Sowing systems seemed to have extreme importance to selection. Sowing oat in hill provided reduced environmental contribution in the expression of panicle weight.