Effect of Plant Pattern and Density on Yield and Amino Acid Profile of Tepary Bean (Phaseolus acutifolius) in a Semiarid Area
Background: Tepary bean is recognized as a deal crop for cultivation in arid and semi-arid regions. The spatial distribution of plants is an important farming practice. A study was conducted in tepary bean (Phaseolus acutifolius A. Gray) to investigate the effect of planting pattern and plant density on plant yield and amino acid profile.Methods: The experiment was carried out in a split-split plot design with three replications during 2017 and 2018. The main plot comprised planting pattern at two levels, including one-row plantation (PP1) and two-row plantation (PP2) and sub plot comprised plant density at three levels, including high plant density (HPD:50 plant/m2), moderate plant density (MPD:40 plant/m2) and low plant density (LPD: 30 plant/m2). In both years, plants were harvested at the end of pod filling stage at October. Amino acid profiles were determined using a HPLC system. Result: The results showed that in the first year and under PP2, MPD increased the biological yield by 19% and 16% compared to HPD and LPD, respectively. Increased pod yield was observed at MPD compared to HPD and LPD. In the second year under PP1, MPD improved grain yield by 75% and 65% in comparison to HPD and LPD, respectively. Increased protein and amino acid content were observed at MPD and PP2. The greatest amino acid content was Leu followed by Lys, Arg, Phe, Val, Ile, Thr, Tyr, His, Met, Trp and Cys.