Induction of Low Temperature Tolerance in Wheat by Pre-Soaking and Parental Treatment with Melatonin

Abstract

Low temperatures seriously depress germination and seedling establishment in wheat and it is of great significance to explore approaches to improve wheat tolerance to low temperatures. In this study, the effects of seed pre-soaking and parental treatment with melatonin on seed germination and low temperature tolerance during the early growing stage in wheat were studied. The results showed that pre-soaking with melatonin increased the germination rate, improved antioxidant capacity and accelerated starch degradation under low temperature, which alleviated low temperature-induced damage to the chloroplasts in coleoptiles of wheat seedlings. Parental melatonin treatment during grain filling stage significantly decreased the grain weight. Seeds from parental melatonin-treated plants showed higher germination rates and higher antioxidant enzyme activity than the control seeds under low temperature. In addition, parental treatment with melatonin modulated the activities of carbohydrate metabolism enzymes, which contributes to enhanced low temperature tolerance in wheat offspring. It was suggested that both seed pre-soaking and parental treatment with melatonin could be the effective approaches for low temperature tolerance induction in wheat.

Melatonin Application Modifies Antioxidant Defense and Induces Endoreplication in Maize Seeds Exposed to Chilling Stress

“…The MEL-treated fruit had a lower level of lipid peroxidation-better membrane integrity than the untreated ones. Thus, the reduction of ROS, lower lipid peroxidation, and decrease in relative electrolyte leakage (a measure of membrane integrity) under the influence of MEL in many plants exposed to various environmental stresses are well documented [56,[62][63][64]. It is certainly related to the MEL direct antioxidant properties as well as its influence on the antioxidant enzyme activity.…”

Using Exogenous Melatonin, Glutathione, Proline, and Glycine Betaine Treatments to Combat Abiotic Stresses in Crops

“…In Zea mays (Maize), the pretreatment of seeds with 0.4, 0.8, and 1.6 mM of melatonin improved the shoot and root lengths, rates of germination, fresh and dry weights of the seedlings, potassium ion (K + ) contents, antioxidant enzyme activities, and relative water content under high salinity conditions [ 43 ]. In Gossypium hirsutum (Cotton), priming the seed with 25 µM of melatonin enhanced the plant’s ability to scavenge ROS and improved photosynthetic efficiency against salt stress [ 44 ]. Seed priming with 70 µM of melatonin enhanced photosynthetic pigments, indole-3-acetic acid (IAA) contents, and growth parameters in Triticum aestivum (Wheat) to avoid the consequences of salinity stress [ 45 ].…”

Melatonin in Plant Defense against Abiotic Stress

“…Application of melatonin at 5 mol L −1 helps to overcome oxidative damage caused by ROS due to an increase in the plant mineral element status and the transcript abundance of antioxidant-related genes as part of a mechanism to overcome cold stress [137]. Pre-soaking seed treatment and parental treatment with melatonin are effective ways for low temperature tolerance induction in wheat [138]. The rootstock of cucurbit species promotes melatonin accumulation in leaves that promote MeJA accumulation and provide tolerance against cold [53].…”