Morphometric, weight, viability, and germination analysis of castor bean seeds (Ricinus communis) under two temperature and relative humidity conditions

Abstract

Objective: Morphometric evaluation, weight, viability and germination under two conditions of temperature and relative humidity in sixteen local varieties of castor beans (Ricinus communis) from various states of Mexico (E1-E16) including two commercial varieties (k75B and k93B) were analyzed.

Design/methodology/approach: The morphometric characteristics were: area, Elongation Index (IE) and Feret's diameter (DF), by means of a vision system. The viability and germination tolerance (germination percentage (% germination), germination speed (VG) and emergence speed index (IVE)), were evaluated under two conditions of relative humidity and temperature (T1- HR 80%/T20ºC ; T2- HR 30%/T40ºC), under a randomized complete block experiment design with four replicates of 75 seeds.

Results: There are morphometric differences (IE, area and DF) between and within the study varieties. There is a significant difference between T1 and T2 in days of radicle emergence (11.6 in T2 and 44.71 in T1), germination percentage (T1: 48.37 and T2: 56%), IVE (T1:34.07+12.72 and T2: 77.02+ 23.78) and VG (T1: 9.93 and T2: 24.60). The results obtained show that there is a positive correlation between the morphometric properties and the germination percentage under T1; but in T2 no correlation was observed.

The Limitations on study/implications: The study did not imply limitations.

Findings/conclusions: Two local varieties E4 and E15 with productive potential higher than 93% under T1 were found; and under T2 the local varieties E3 and E16 with a productive potential greater than 78%, with respect to the commercial variety k75B showed a better performance under T1 (89.75%) than under T2 (78.67%).