Development of clonal seedlings of promising Conilon coffee (Coffea canephora) genotypes
Australian Journal of Crop Science
Conilon coffee is a highly heterozygous diploid plant that is also allogamous, producing seeds through cross-fertilisation. Due to their allogamy, plants of seminiferous origin are highly heterogeneous, exhibiting high morphological and genetic diversity. However, propagation through cutting guarantees the maximum homogeneity of fields, particularly in grain maturation, among other desirable characteristics. Currently, the majority of commercial Conilon coffee is planted using seedlings
... g seedlings propagated by cuttings. Studying the juvenile behaviour of different clonal genotypes of the Conilon coffee plant represents an important tool to assist with the establishment of this crop. The objective of this study was to assess the growth, development and genetic diversit y in several promising genotypes of the Conilon coffee plant based on the morphological characteristics of seedlings propagated by cutting. We used seedlings Conilon coffee of 33 genotypes selected by coffee growers, and with great productive potential, and genotype 02 of the Emcapa 8111 variety. Based on morphological characteristics linked to the growth and development of the aboveground and root systems of the genotypes, their phenotypic correlations were estimated, along with the genetic diversity among genotypes, using Tocher's optimisation method and the unweighted peer group method with arithmetic mean. Genotypes A1, P2, Z39, Ouro Negro, Tardio C, Cheique, and Z29 exhibited a higher Dickson quality index (between 0.40 and 0.56). Genetic variability exists among the seedlings of the 34 genotypes of Conilon coffee studied. The most dissimilar genotypes were CHR, 18, and Z39, which remained in isolated groups in all experiments. planting by cutting DQI_Dickson quality index; EMS_etiolation of the main stem; ICO_International Coffee Organization; LA_leaf area; LDM_leaf dry matter; LLR_length of largest root; MAPA_Brazilian Ministry of Agriculture; NIPS_number of internodes on the primary stem; NISS_number of internodes on the secondary stem; NOS_number of orthotropic shoots; NPR_number of primary roots; NPTB_number of plagiotropic branches; PSBD_primary stem base diameter; PSH_primary stem height; RDM_root dry matter; RV_root volume; SDM_stem dry matter; SLM_specific leaf mass; SSBD_secondary stem base diameter; SSH_secondary stem height; TDM_total dry matter; and UPGMA_hierarchical unweighted pair group method with arithmetic mean.