Effects of planting density on vegetative growth and production components of jatropha (Physic nut L)

Abstract

Planting configuration is a management factor that influences production. Despite its importance for the establishment of commercial plantations of jatropha, the best planting configuration is still unknown, since its optimal planting density varies widely according to the climate and soil conditions of each region. This study aimed to determine the best planting configuration for jatropha cultivated in the Agreste region of Paraíba, Brazil. An experiment was set up in a randomized block design with 4 replicates. The mean values of plant height, leaf area, number of fruits per plant, number of seeds per plant, number of fruiting branches per ha, number of fruits per ha, number of bunches per ha and production of seeds per ha were significantly influenced by planting density in dense plantations. The highest seed production per ha was obtained at a density of 2,500 plants ha -1 (narrowest spacing).Keywords: Jatropha curcas L; spacing; production. Abbreviations: S: _Sum of bases; T_Cation exchange capacity; V_Saturation of bases; OM_Organic matter; LA_Leaf area, PH_plant height, SD_stem diameter, NVB/pl_number of vegetative branches per plant, NVB/ha_number of vegetative branches per ha, NFB/pl_number of fruiting branches per plant, NFB/ha_number of fruiting branches per ha, NInf/pl_number of inflorescences per plant, NInf/ha_number of inflorescences per ha, NF/pl_number of fruits per plant, NF/ha_number of fruits per ha, NBunch/pl_number of bunches per plant, NBunch/ha_number of bunches per ha, NS/pl_number of seeds per plant, NS/ha_number of seeds per ha, Prod/pl_production of seeds per plant, Prod/ha_production of seeds per ha, Σ_sum of leaf area, L_midrib length, W_leaf width.

Effect of nitrogen and potassium on plant height and stem diameter of Jatropha curcas L. in Colombian tropical dry forest

“…In this sense, tree growth is supported by the trunk and must be biomechanically balanced (Montagu et al, 2005); in other words, stem diameter is related to the length and distribution of branches and should prevent uprooting or branch split. In J. curcas, stem diameter and number of branches (Laviola et al, 2012) as well as plant height (Laviola et al, 2012;Shabanimofrad et al, 2013;De Lima et al, 2016) were shown to correlate positively with seed yield per plant.…”

“…This increases the number of fruits per plant, facilitates control of pests and weeds, and provides easy harvesting by gaining access to all sectors of the crop canopy. According to de Lima et al (2016), J. curcas tends to increase height at high sowing densities due to interspecific competition, a condition that accelerates plant development and fruit production in this species. The same authors obtain the minimum seed yield per plant at the highest sowing density (2,500 plants ha -1 ).…”

Yield productivity enhancement through reduced plant spacing and pruning tolerance of Jatropha hybrids

“…Although increasing plant density by decreasing plant spacing may increase Jatropha yield per planted area, increased competition between plants may harm growth and yield (Andrianirina et al 2019;Lima et al 2016). The density of the plant population signi cantly impacted the growth and development of Jatropha, affecting both its vegetative and reproductive aspects.…”

“…Previous research has recommended planting Jatropha with fairly wide spacing, such as 3 × 3 m to 4 × 4 m, as suggested by Singh et al (2013) and Huse et al ( 2011). Jatropha breeding has resulted in new genotypes with smaller canopies, which means that many areas of Jatropha cultivation can now use narrower plant spacing of 2 × 2 m or 2 × 1.5 m (Santos et al 2016;Lima et al 2016;Tar et al 2011). Narrow spacing with smaller canopies of Jatropha was achieved from a crossing between J. curcas and J. integerrima, resulting in hybrids (Arunyanark et al 2023a;Muakrong et al 2014b;One et al 2014a).…”

“…Jatropha breeding has developed smaller canopy sizes, making it possible to plant them with narrower spacing, especially genotypes from crossing J. curcas with J. integerrima, which has a much smaller canopy than J. curcas(Santos et al 2016;Lima et al 2016;Tar et al 2011). As a result, inter-speci c hybrids with more compact canopy sizes were selected(Arunyanark et al 2022a;One et al 2014a…”