SPATIAL-TEMPORAL PATTERNS OF COFFEE TREE PHYSIOLOGY

The ecophysiological parameters of coffee canopy were mapped throughout the day. Therefore, evaluations were carried out in ‘Catuaí Vermelho’<em> Coffea arabica</em> L., measuring 1.7 meters. 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 was performed on the east and west sides of the canopy, at four times of the day: 6 a.m., 9 a.m., noon, and 3 p.m., totaling 24 collection points at each time. Gas exchange, photosynthetically active radiation and leaf temperature were evaluated in each of the 24 points of the coffee canopy. The gas exchange characteristics of an individual coffee leaf diverge considerably from other leaves, which require caution when scaling estimates of leaf photosynthesis at the global canopy level. The analysis of some punctual leaves does not serve to discriminate the overall dynamics of a canopy.

Download Full-text

SPATIO-TEMPORAL VARIABILITY OF CARBOHYDRATE AND CHLOROPHYLL CONTENT IN THE COFFEE CANOPY

Coffee Science ◽

10.25186/cs.v14i3.1590 ◽

2019 ◽

Vol 14 (3) ◽

pp. 366

Author(s):

Paula Tristão Santini ◽

Lorena Gabriela Almeida ◽

Kamila Rezende Dázio de Souza ◽

João Paulo Rodrigues Alves Delfino Barbosa ◽

José Donizeti Alves

Keyword(s):

Chlorophyll Content ◽

Soluble Sugars ◽

Vertical Direction ◽

Vertical Gradient ◽

Horizontal Gradient ◽

Coffee Plant ◽

Chloroplast Pigments ◽

Spatio Temporal ◽

Inner Parts ◽

Plagiotropic Branches

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.

Download Full-text

Roles of leaf trichomes in heat transfers and gas‐exchange characteristics across environmental gradients

10.22541/au.160794364.42389606/v1 ◽

2020 ◽

Author(s):

Gaku Amada ◽

Yoshiko Kosugi ◽

Kanehiro Kitayama ◽

Yusuke Onoda

Keyword(s):

Gas Exchange ◽

Low Temperature ◽

Environmental Gradients ◽

Gas Diffusion ◽

Leaf Temperature ◽

Heat Diffusion ◽

Diffusion Resistance ◽

Leaf Trichomes ◽

Gas Fluxes ◽

Gas Exchange Characteristics

Dense leaf trichomes can directly decrease gas fluxes through increased gas diffusion resistance and indirectly increase gas fluxes through increased leaf temperature due to increased heat diffusion resistance, which may contribute to adaptation to dry and/or low‐temperature conditions. However, it remains unclear whether the leaf‐trichome resistance increases or decreases the gas‐exchange rates through combined direct and indirect effects. We focused on Metrosideros polymorpha, a dominant tree species inhabiting a large range of environmental gradients in the Hawaiian Islands, whose leaves have an enormous variation in trichome thickness on the lower surface. In five elevational sites, we measured leaf morphological and physiological traits including trichome thickness, gas‐exchange characteristics, and leaf temperature. The trichome thickness was largest in the coldest and driest site and thinnest at the wettest site. Leaf temperature was significantly increased with trichome thickness. With biophysical and physiological models, we show that leaf trichomes can increase the daily photosynthesis through increasing leaf temperature only in the cold alpine area. The daily water‐use efficiency can be lower with increasing leaf trichomes at any elevational sites. Therefore, in terms of diffusion resistance, the leaf trichomes of M. polymorpha can contribute to the adaptation to low‐temperature environments but not to dry environments.

Download Full-text

Relationship Between Evolutionary Adaptation and Gas Exchange Characteristics of Diverse Sorghum Taxa

Australian Journal of Biological Sciences ◽

10.1071/bi9710843 ◽

1971 ◽

Vol 24 (4) ◽

pp. 843 ◽

Cited By ~ 9

Author(s):

RW Downes

Keyword(s):

Gas Exchange ◽

Leaf Temperature ◽

The Other ◽

High Radiation ◽

Gas Exchange Parameters ◽

Low Light ◽

Active Radiation ◽

Gas Exchange Characteristics ◽

Radiation Conditions ◽

Exchange Parameters

Ten species and varieties of Sorghum were conditioned to either full or part sunlight. Gas exchange parameters of attached leaves were determined under a range of levels of photosynthetically active radiation and leaf temperature. S. arundinaceum which originated in the low light environment of equatorial forests was capable of higher rates of photosynthesis and greater stomatal opening if it was conditioned to low rather than high radiation conditions. In this respect it differed from the other species though all have the characteristics of plants with the C4 pathway of photosynthesis. Generally species from high radiation environ. ments were capable of the highest rates of photosynthesis though some exceptions were noted. Genetic implications are briefly discussed.

Download Full-text

Decline of vegetative growth in Coffea arabica L. in relation to leaf temperature, water potential and stomatal conductance

Field Crops Research ◽

10.1016/s0378-4290(97)00045-2 ◽

1997 ◽

Vol 54 (1) ◽

pp. 65-72 ◽

Cited By ~ 38

Author(s):

Raimundo S. Barros ◽

Jay Wallace da S.e Mota ◽

Fábio M. Da Matta ◽

Moacyr Maestri

Keyword(s):

Stomatal Conductance ◽

Water Potential ◽

Vegetative Growth ◽

Coffea Arabica ◽

Leaf Temperature ◽

Coffea Arabica L ◽

Temperature Water

Download Full-text

Selection of coffee progenies for resistance to nematode Meloidogyne paranaensis in infested area

Cropp Breeding and Applied Biotechnology ◽

10.1590/1984-70332014v14n2a17 ◽

2014 ◽

Vol 14 (2) ◽

pp. 94-101 ◽

Cited By ~ 11

Author(s):

Sonia Maria Lima Salgado ◽

Juliana Costa de Rezende ◽

José Airton Rodrigues Nunes

Keyword(s):

Genetic Variability ◽

Coffea Arabica ◽

Mixed Model ◽

High Rate ◽

Germplasm Bank ◽

Genotypic Association ◽

Coffee Plants ◽

Plagiotropic Branches ◽

Mixed Model Methodology ◽

Selection Of

The purpose of this study was to select Coffea arabica progenies for resistance to M. paranaensis in an infested coffee growing area using Henderson's mixed model methodology. Forty-one genotypes were selected at the Coffee Active Germplasm Bank of Minas Gerais, and evaluated in regard to stem diameter, number of plagiotropic branches, reaction to the nematode, and yield per plant. There was genetic variability among the genotypes studied for all the traits evaluated, and among the populations studied for yield and reaction to the nematode, indicating possibilities for obtaining genetic gains through selection in this population. There was high rate of genotypic association between all the traits studied. Coffee plants of Timor Hybrid UFV408-01 population, and F3 progenies derived from crossing Catuaí Vermelho and Amphillo MR 2161 were the most promising in the area infested by M. paranaensis.

Download Full-text