Effect of Soil Moisture Deficit Stress on Biomass Accumulation of Four Coffee (Coffea arabica) Varieties in Zimbabwe

Abstract

A study was conducted to evaluate four common coffee (Coffea arabica) varieties in Zimbabwe for drought tolerance and ability to recover. The plants were subjected to drought stress for 21 and 28 days with evaluation of recovery done 14 days after interruptive irrigation. Coffee varieties were not significantly different in initial fresh and dry biomass before stressing (P>0.05). CR95 had significantly accumulated more (P<0.05)dry root mass (0.8 g) than the rest of the varieties after 21 days of drought stress. SL28 and CR95 had an 8.3% increase in dry biomass while Cat128 did not gain any dry biomass after 21 days of drought stress. CR95 had significantly more (P<0.05) total dry biomass after 21 days and 28 days of drought stress while SL28 was consistently the least in both periods. Cat129 had the highest recovery gains in dry root, dry shoot, and total dry biomass after 21 days and 28 days of drought stress. Initial root biomass was negatively correlated with changes in total fresh and dry biomass of young coffee (r>0.60) after both 21 and 28 days of drought stress, indicating that root biomass may be the most important factor determining drought tolerance in coffee varieties.

Effects of fertilization on the growth, photosynthesis, and biomass accumulation in juvenile plants of three coffee (Coffea arabica L.) cultivars

“…The shoot to root ratio of trees shifted with age, generally from the 4:1 (one-year-old) assumed for tropical trees to 2:1 (Van Noordwijk et al 2002). In the present study, about 75.76−84.43% of the dry matter of the coffee plants come from aboveground, similar to one-year-old arabica coffee (Chemura et al 2014). In addition, it was found that N is the most important factor influencing the growth and photosynthesis of C. arabica plants, followed by K, while P has the least influence on adult plants (Cai et al 2004).…”

Growth Response of Seedlings of Four Robusta Coffee (Coffea canephora Pierre. Ex. A. Froehner) Clones to Drought Stress

“…The results of this research are in line with that of Mohammed et al (2018) which state that drought stress for 28 days (4 weeks) causes a significant difference in the growth of Robusta coffee plants, and this could be seen more clearly in the variable of total dry weight of plants. Similar findings are also found in Arabica coffee seedlings, namely 21 days of drought stress causes significant differences in plant biomass accumulation (Chemura et al, 2014).…”

Humification degree and its relationship with some soil physical characteristics on robusta coffee (Coffea canephora) plantation

“…Stress of soil moisture on Robusta coffee plant decrease plant growth, plant biomass, fruit production, number of intact grains, three group of coffee grains, and increase the amount of the empty beans (DaMatta and Ramalho, 2006;Sumirat, 2008;Chemura et al, 2014). The biological properties of Robusta coffee grown under the shade is one of the characteristics of Robusta coffee that makes the coffee plant takes up the organic material from the litter into the soil and affects to the content of the humic substances in the soil (Baon dan Wibawa, 2005;Souza et al, 2012;deAlcantara-Notaro et al, 2014).…”