Evaluation of Lima Bean Accessions at High Temperatures

Abstract

- Lima bean (Phaseolus lunatus L.) develops at an optimal temperature in the range of 20-30°C, temperatures above 30-35°C compromise the photosynthetic efficiency of the crop. Considering the importance of lima bean cultivation, the objective of this study was to carry out a morphoagronomic and phenological characterization of 46 lima bean accessions tolerant to high temperatures from the core collection of lima bean at the Universidade Federal do Piauí. The experiment was conducted from February to July 2021 in a completely randomized block design with four replications, where the plot consisted of a pot with two plants. Genotype characterization was performed based on 20 morphoagronomic and phenological descriptors of lima bean. Based on Pearson's correlation, the number of emitted and aborted flowers had a greater genetic correlation with the total number of seeds and pods produced. Pod length and width were positively correlated with seed thickness, length, and width. Five groups were formed based on UPGMA grouping. It was observed that the UFPI-922 and UFPI-945 accessions had a higher performance under high-temperature conditions in relation to the number of flowers and pods emitted, as well as lower values for the number of aborted pods. The accessions UFPI-1037, UFPI-876, UFPI-1036, UFPI-1028, UFPI-1052, UFPI-1064, UFPI-1038, and UFPI-1062 are promising for precocity, productivity, emission of flowers and pods formed, and can be used in breeding programs.

Andean Lima Bean Ecology and Its Potential Contribution to Food Security

“…Another study conducted by Machado et al. (2022) report that P. lunatus shows good growth performance under high‐temperature conditions in terms of the number of flowers and pods produced, as well as lower values for the number of aborted pods, demonstrating its ability to adapt to different climatic conditions.…”

“…In addition, the ecological descriptors of this species indicate an altitudinal range of 0 to 2.386 m.a.s.l., an annual temperature range of 13.2 to 29.9 °C, and an annual rainfall range of 400 to 4.250 mm, which shows its ability to adapt to different climatic conditions (Barrera-Sánchez et al 2020). Another study conducted by Machado et al (2022) report that P. lunatus shows good growth performance under high-temperature conditions in terms of the number of flowers and pods produced, as well as lower values for the number of aborted pods, demonstrating its ability to adapt to different climatic conditions.…”

“…Some varieties may have difficulty in germinating if soil temperatures are below 20 °C, and germination is optimal in the range of 21 to 27 °C (Duke 1981). A recent study conducted by Machado et al (2022) in Brazil characterized 46 P. lunatus L. accessions from various countries. The accessions were planted in pots and evaluated for high temperature conditions, morphology, and phenology.…”

“…In general, it does not tolerate high salt concentrations, but some varieties, especially Andean varieties from Peru, do well in saline conditions (FAO 2018). For example, Machado et al (2022) reported that as for soil pH, a range of 5.5 to 7.5 is recommended for cultivation and pH values of 4.3 to 8.3 have been reported in different studies.…”

“…For example, Machado et al. (2022) reported that as for soil pH, a range of 5.5 to 7.5 is recommended for cultivation and pH values of 4.3 to 8.3 have been reported in different studies.…”