Chia (Salvia hispanica L.) Seed Soaking, Germination, and Fatty Acid Behavior at Different Temperatures

Abstract

The temperature reduces the viability and seed vigor; however, the effect of temperature on imbibition and fatty acid profile has not been studied. Chia (Salvia hispanica L.) seeds have a substantial quantity of oil, making them a potential study model for fatty acid metabolism. Therefore, we explore the effect of temperature (10, 20, and 30 °C) on chia seed imbibition, germination, and fatty acid profile by GC-MS. Imbibition FI occurs within the first hour in all the treatments; while FII and FIIend elapse with an hour of difference at 20 °C and 30 °C. The highest viability and germination rate were observed at 30 °C; while the highest concentrations of all fatty acids, except oleic acid, were observed at 20 °C. Maximum fatty acid concentrations were detected at FI and FIIend; while at 30 °C, different patterns for saturated and unsaturated fatty acids and three linolenic acid isomers were observed. A shorter FII is associated with earlier germination; the increase in concentration in fatty acids after 3 h and a negative correlation between linoleic and linolenic acid observed at 20 °C were related to a higher germination efficiency. At 30 °C, isomer formation is related to homeoviscous cell membrane adaptation.

Quantifying Cardinal Temperatures of Chia (Salvia hispanica L.) Using Non-Linear Regression Models

“…Our observed optimal condition, i.e., the temperature(s) at which the germination percentage is high, and germination occurs the fastest, in this case, 25-35 • C, is almost ten degrees above the reported range [41]; this evidence agrees with our previous results [24] and with those observed by Paiva et al [25,26]. The differences in the germination of chia varieties generated by domestication are mainly associated with different capabilities to germinate and grow under different climatic conditions [27], like those varieties produced to grow during the long days of the northern hemisphere [45,46].…”

“…Upon germination, the progressive depletion of oxygen generates conditions that almost achieve anaerobiosis, and fermentation is triggered as the main source of cellular ATP, supporting the reduction of electron transferring compounds, e.g., NAD and NADP, and inevitably leading to ROS (reactive oxygen species) accumulation [75]. In the case of S. hispanica, we observed that in a temperature range from 10 • C to 20 • C, germination undergoes a lag phase; above that temperature, germination increases exponentially as it approaches the optimal temperature, this evidence suggests that mucilage could have a temperature where its moisture-holding capacity changes, allowing germination to proceed more quickly; this agrees with our previous observations [24].…”

“…Five replicates of 25 seeds were sown randomly on an agar medium (10 g L −1 ) in Petri dishes (5.5 × 1.5 cm). Seeds were incubated at constant temperatures in germination chambers at 10 • C to 45 ± 2 • C (with intervals of 5 • C) with a 12 h photoperiod, the same as Cabrera-Santos et al [24] and Sampayo-Maldonado et al [85]. Seeds were considered germinated when the radicle emerged ≥ 2 mm [86]; after that, seedlings were removed from the Petri dish.…”

“…On this subject, during the year 2018, the chia seed worldwide market was valued at USD 66.5 million; by the year 2024, the market is projected to reach a value of USD 88.1 million [23]. Experimental evidence about S. hispanica is still in progress, especially concerning seed technology, including the role of temperature on germinative behavior [24][25][26]. Therefore, it is necessary to obtain enough knowledge about the factors underlying germination and plant development, following different approaches to support chia agricultural practices.…”

Non‐chlorophyllous and crypto‐chlorophyllous fern spores differ in their mobilisation of fatty acids during priming

“…For the analysis of the methyl esters of fatty acids, we followed the method of Cabrera‐Santos et al ( 2021 ). To identify the fatty acids, a gas chromatograph was used (GC; Agilent Technologies 6850), coupled with a mass spectrometer (MS; Agilent Technologies 5975C VL MSD).…”