germination, local varieties, Ricinus communis, viability
Objective: To analyze the morphometric, weight, viability, and germination evaluation under two temperature and relative humidity conditions, in sixteen local varieties of castor bean (Ricinus communis) from several states of Mexico (E1-E16), as well as two commercial varieties (k75B and k93B).
Design/Methodology/Approach: The following morphometric characteristics were analyzed using a vision system: area, elongation index (EI), and Feret's diameter (FD). Viability and germination tolerance (germination percentage (GP)), germination speed (GS), and emergence speed index (ESI)) were evaluated under two conditions of relative humidity and temperature (T1 - RH 80%/T 20ºC; T2 - RH 30%/T 40ºC), using a completely randomized block experiment design, with four replicates of 75 seeds.
Results: There are morphometric differences (EI, area, and FD) between and within the study varieties. There are significant differences between T1 and T2 regarding the following variables: days of radicle emergence (T1: 44.71 and T2:11.6), germination percentage (T1: 48.37 and T2: 56%), ESI (T1: 34.07+12.72 and T2: 77.02+ 23.78), and GS (T1: 9.93 and T2: 24.60). The results obtained show a positive correlation between the morphometric properties and the germination percentage in T1; however, there was no correlation in T2.
Study Limitations/Implications: There were no limitations to carry out this study.
Findings/Conclusions: The E4 and E15 local varieties obtained a >93% productive potential in T1, while the E3 and E16 local varieties obtained a >78% productive potential in T2. Meanwhile, the k75B commercial variety had a better performance in T1 (89.75%) than in T2 (78.67%).