Productivity and Oil Content in Relation to Jatropha Fruit Ripening under Tropical Dry-Forest Conditions

Abstract

Jatropha is promoted as a pro-poor bioenergy plant, while basic information about its productivity, age of maximum production, and oil content are missing. This study aims to determine the seed yield (dry weight) for three INIAP elite jatropha accessions, and to evaluate the changes in physical and chemical seed traits at the different fruit ripening stage in a split-plot design. Maximum seed production occurred four years after planting for the accessions CP041 and CP052, while for accession CP054, it occurred after the first year. CP041 was the most productive, with a mean of 316.46 g tree−1 year−1 (±76.50) over the 8-year study period. No significant differences in oil content were found among accessions, fruit ripening stage, and their respective interactions. Seed moisture content decreased drastically as the fruit ripening stage increased, from 40.5% ± 1.0% at fruit ripening stage 1 (greenish-yellow) down to 13.8% ± 0.4% at fruit ripening stage 4 (black-brown). No significant differences in seed weight were found among accessions, but it decreased as maturation progressed. Yellow fruits (stage 2) were the heaviest (62.4 g ± 1.5 g) and the black-brown fruits the lightest (44.3 g ± 1.9 g). The oil content (%) increased with seed weight up to the point of 58.3 g, but then decreased for heavier seeds.

Control of mosaic disease using microbial biostimulants: insights from mathematical modelling

“…Baseline values of parameters are taken from Holt et al [61], Venturino et al [10], and Al Basir and Roy [7]. Regarding carrying capacity of plants, we consider a plantation with a maximum of 50 plants, which, with a recommended spacing of around 3 m × 3 m for cultivating Jatropha [65] would correspond to a plot of 450 m 2 , which is consistent with average-size fields and farm plots used for growing Jatropha [66,67] and cassava [68]. It should be noted that although we have chosen to fix the maximum number of plants, an alternative is to rather treat this carrying capacity as plant density per some pre-defined plot area [1,61], so that one could then consider a large plantation or a field consisting of a multitude of such plots.…”

In situ assessment of Jatropha curcas germplasm under tropical dry forest conditions in Manabí-Ecuador

“…The study was conducted at the Portoviejo Research Station (EEP), which belongs to the National Institute for Agricultural and Cattle Ranching Research (INIAP) (0°6'S, 80°23'W), Lodana Sector, Canton Portoviejo, Province of Manabí, Ecuador. The EEP is located at 47 masl, with a mean annual temperature of 26.3 °C, mean annual precipitation of 809.6 mm, mean relative humidity of 83% and mean number of sunshine hours of 1,159.3 h year -1 (Cañadas-López et al, 2018a;Cañadas-López et al, 2018b). The research area is ecologically classified as a tropical dry forest (Cañadas, 1983).…”

Pruning and fertilization effects on Jatropha yields under smallholder’s conditions in a Tropical Dry Forest from Ecuador

“…A relatively unpredictable annual dry seed production and low seed production over time are the significant drawbacks of the jatropha tree for biofuel production (Rade-Loor et al, 2017;Cañadas-López et al, 2017;Cañadas-López et al, 2018). Thus in 2014, with a precipitation of 824 mm in the rainy season (between January and May), the seed yield in the pruned trees was only 74.86 kg ha -1 ; in 2015, the yield was 849.54 kg ha -1 (rainy season precipitation 806 mm); and in 2016, the yield was 1,074.46 kg ha -1 (rainy season precipitation 745 mm).…”

“…In 2011 the Ecuadorian Government began a project entitled "Renewable Energy for the Galapagos Islands" within the "Jatropha for Galapagos Project" aimed at reducing the use of fossil fuel (diesel oil) to generate electricity on Floreana Island. The province of Manabí was selected for establishing trial jatropha plantations (Cañadas-López et al, 2018).…”