Abstract
The spatial variability of the total chlorophyll content and carotenoids content, starch and soluble sugars of coffee canopy were mapped throughout the day. Therefore, evaluations were carried out in a ‘Catuaí Vermelho’ coffee plant with 1.7 meters height. A vertical gradient (from the apex to the base of the plant canopy) and a horizontal gradient (plagiotropic branches) were established to analyze different positions of the canopy. Thus, in the vertical direction, four heights were analyzed in the plant: top, upper, middle and lower regions. In the horizontal gradient, the plagiotropic branches were divided into three parts: basal, median and apical. Collection of leaf samples was performed on the east and west sides of the canopy, at 9 a.m., totaling 24 collection points at each time. Higher content of photosynthetic pigments and concentration of sugars were observed in the western face and in the inner parts of the coffee tree. The content of chloroplast pigments and sugars of an individual coffee leaf diverge considerably from other leaves, which requires caution when scaling estimates at the global canopy level. The analysis of some punctual leaves does not serve to discriminate the overall dynamics of a canopy.
Highlights
The coffee tree is native from the African continent, grown in shady environments, but it has been usually cultivated in sunny environments, with high production (POMPELLI et al, 2010)
Chlorophyll and carotenoids content were higher in the western face of the coffee tree (Figure 2)
Total soluble and reducing sugars were more concentrated in the middle region of the western face (Figure 3 B and C), while the amount of starch was higher in fruits located at middle and lower regions of the both sides of the canopy (Figure 3 A)
Summary
The coffee tree is native from the African continent, grown in shady environments, but it has been usually cultivated in sunny environments, with high production (POMPELLI et al, 2010). Different parts of the plant canopy can respond differently to environmental variations, once there are variations in the physical structure of the canopy, the age of the leaves and the distribution and translocation of the photo assimilates among the different parts and heights in the canopy of the plant (RODRÍGUEZ et al, 2011) These changes in canopy position may lead to different responses, such as photosynthetic, anatomical modifications, pigment content and biochemical changes in coffee metabolism (CHAVES et al, 2012). The usual indication for analysis of the coffee canopy is the collection of the 3rd or 4th pair of leaves from the apex of productive branches, from each side of the plant, at the medium height of the plant (GUIMARÃES et al, 1999). There are still differences in literature between authors regarding the number of leaves, branches and fruits to be collected per sampling unit for diagnosis purposes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
