Crescimento em campo de mudas do clone CO1572 aptas e não aptas para o plantio

Abstract

The production of eucalyptus seedlings, especially through clonal seedlings, has been highlighted for presenting important factors in the formation of plants, ensuring quality and uniformity in plant growth in the field. However, not all seedlings produced have favorable morphological characteristics for planting. Therefore, the objective of the study was to evaluate the influence of the morphological and qualitative characteristics of seedlings in the nursery on the initial performance in the field, aiming to identify quality criteria that best predict the success in the establishment of seedlings in the field. From a single batch of seedlings of clone CO1572, 480 seedlings were selected and divided equally into two treatment groups: "suitable" and "not suitable" for planting in the field, according to the technical selection criteria adopted by the company. Of the suitable and not suitable seedlings, continuous quantitative variables were evaluated in the nursery: height of the aerial part, diameter of the stem and number of pairs of leaves; and qualitative variables such as: presence or absence of active roots, substrate aggregation, rusticity, exposed roots, broken tips or mechanical damage, bifurcation and inclination in the seedlings. The two groups of seedlings were planted in the field with a spacing of 2.5 x 3.6 m, considering 5 blocks of 48 seedlings each. Data collection occurred 28, 57 and 98 days after planting. The variables analyzed in the field were: height of the aerial part, diameter at ground level and mortality rate. It can be concluded that the suitable seedlings actually present better growth results, showing better plant performance in the field, when compared to the unsuitable seedlings. The variables of the CO1572 clone that most positively influenced the growth of the seedlings in the field were the height and diameter in the nursery and rustication, while those that most negatively influenced were inclination and bifurcation. Keywords: Rustification, seedling quality, survival, clonal seedlings.