Vegetative growth of 28 genotypes of Coffea canephora at 850 meters of altitude

Abstract

Coffea canephora plants grown at low or elevated temperatures undergo changes in photosynthetic processes, which have a direct impact on vegetative growth. This species shows plants with distinct stress tolerance mechanisms and a great genetic diversity; however, there are no studies concerning the study of altitude on plant growth for these genotypes. The objective of this study was to evaluate the growth rates of orthotropic and plagiotropic branches from 28 Coffea canephora genotypes, ca. 3 years of age, cultivated at 850 m of altitude. The experimental design was a randomized complete block design with four repetitions. Each repetition was compounded by five plants. The period of the experimental evaluation was from 01/23/2013 to 07/07/2013. We selected and identified the orthotropic and plagiotropic branches, which were evaluated bimonthly according to their length (mm), assessing the growth rates. The results were associated with climatic factors that occurred during the experimental period. The genetic material of Coffea canephora evaluated in the study shows genetic diversity to the characteristics growth rate of orthotropic and plagiotropic branches, thus, it is possible to select genotypes with potential for cultivation at 850 m of altitude. In general, genotypes of Coffea canephora exhibited variations in growth rates, mainly in response to changes in temperature, with a sharp and constant drop in growth rates between the period from 05/05/2013 to 05/ 23/2013, when the recorded temperatures were always below 13 °C. Genotypes A1, NV2 and NV1 can be pointed as the ones which showed the best vegetative growth results at 850 meters of altitude.