Sunflower and peanut emergency : initial development under sugarcane mulch.

The research aimed to evaluate the effect of residual sugarcane mulch on sunflower and peanut plant emergence and initial development. Vases of 4.0 L were disposed in a randomized experimental blocks design, with four replications, in a factorial arrangement of five mulch amounts and three cultivars of each crop. The mulch treatments consisted of four increasing amounts (5, 10, 15 e 20 t ha-1) and a tester with no mulch. The sunflower cultivars were the varieties IAC-iarama and Catissol and the hybrid H-358; the peanut cultivars were IAC-Caiapó, Runner 886 and Tatu. The speed emergency index and final percentage, the plant height and shoot dry mass were evaluated. The presence of different levels of sugarcane mulch negatively influences the emergency and initial plant development mainly in peanut but also in sunflower. The negative effects are stronger especially for the runner type of peanut cultivars, while cultivar Tatu was less influenced by the mulch thickness.

Development of super early genotypes for the dry bean (Phaseolus vulgaris) as affected by nitrogen management.

The super early genotypes (SEG) of dry bean (Phaseolus vulgaris L.) have a shorter life cycle (65-75 days) when compared with the season length of traditional cultivars (90-100 days). Timing of nitrogen top-dressing fertilization could be different because of this reduction in length of the SEG life cycle. This study aimed at characterizing, by using growth analysis and vegetation index, super early genotypes of dry bean development as affected by timing of nitrogen application. Field experiments were conducted in the 2014 and 2015 growing seasons in central Brazil with a randomized block experimental design with split plots scheme and four replicates. The plots comprised the dry bean genotypes (Colibri ? check cultivar, CNFC 15873, CNFC 15874, and CNFC 15875), and subplots comprised applications of N at different timings: 90 kg of N at sowing, 90 kg N at top-dressing; 45 kg of N at sowing plus 45 kg at top-dressing, with urea as the source of N. We also used a control treatment without N application. The CNFC 15874 super early genotype of dry bean had the higher grain yield (2776 kg ha-1) and differed from the CNFC 15873 genotype (2492 kg ha-1). Nitrogen fertilization allowed higher grain yield (2619 kg ha-1, when applied N at sowing, 2605 kg ha-1, when applied N at sowing and at top-dressing, and 2680 kg ha-1, when applied N at top-dressing) than the control, 2360 kg ha-1 (no N fertilization). The time of N fertilization in super early genotype of dry bean did not affect grain yield.

Evaluation of the productive and vegetative aspects of the cultivar 'Imperial Gala' apple tree with EM-9 interstem in different lengths.

The obtaining of a compact plant, with less vigor and high productivity, equivalent to a conventional plant, constitutes a strong tendency in the current horticulture, aiming at a raising of the fruit production at the same planted area. One of the techniques that have had success nowadays is the interstem use. This study was developed in a commercial orchard of Randon Agro Silvo Pastoril S.A. (RASIP), located in the Rio Grande do Sul state, Brazil. The purpose of this work was to evaluate the vegetative and productive development of apple trees of 'Imperial Gala' with different lengths of EM-9 interstem. The treatments consisted of five interstem lengths: 10, 15, 20, 25, 30 cm. In the seventh year of implantation the following parameters were evaluated: the height of the plant, the diameter of the 'Imperial Gala' 5 cm above the second graft point, the volume of the tree-head (height, width and length), the number of bud per branch, and the number of fruits per lineal centimeter of branch. Through this study it could be concluded that the greater interstem (30 cm) presented better indices with relation of vigor control. However, the number of fruits per lineal centimeter of branch with the interstem of 10 cm offered only significant superiority, when compared with the interstem of 30 cm. Using interstem technique allows to gather the benefits of the rootstock 'Marubakaido' and to control excessive vigour with the interstem EM-9.

Burrknots as food source for larval development of Grapholita molesta (Lepidoptera: Tortricidae) on apple trees.

Grapholita molesta (Busck) is one of the main pests of apple trees, and lives on their shoots and fruits. In southern Brazil, the insect is also found on old branches and structures similar to aerial roots, so-called burrknots. This study evaluated the development and population growth potential of G. molesta fed on burrknots, compared with apple fruit cultivar. Fuji and a corn-based artiÞcial diet. The study was carried out in the laboratory under controlled temperature (25 1C), relative humidity (7010%), and photophase (16 h). The biological parameters of the immature and adult stages were determined, and a fertility life table was constructed. Insects fed on burrknots showed a longer duration and a lower survival for the egg-to-adult period (29.3 d and 22.5%) compared with those that fed on apples (25.1 d and 30.0%) and artiÞcial diet (23.9 d and 54.8%). Insects reared on aerial roots had a lower pupal weight (10.0 mg) compared with those reared on either artiÞcial diet (13.7 mg) or apple cultivar. Fuji (12.4 mg). The fecundity and longevity of males and females did not signiÞcantly differ for the three foods. Based on the fertility life table, insects reared on burrknots had the lowest net reproductive rate (Ro), intrinsic rate of population growth (rm) and finite rate of increase, compared with insects reared on artiÞcial diet and apple fruit. Burrknots support the development of the complete cycle of G. molesta, which allows populations of this pest to increase in orchards.