Effects of Maternal Environment on Seed Germination and Seedling Vigor of Petunia × hybrida under Different Abiotic Stresses.

Chi D Nguyen,Hector Perez,Jianjun Chen,David Clark,Heqiang (Alfred) Huo

doi:10.3390/plants10030581

Abstract

Seed germination and seedling vigor can be affected by environmental cues experienced by the mother plant. However, information about how the maternal environment affects seed quality is scarce in ornamental plants. This study aimed to investigate the effects of two different maternal environments on the seed germination and seedling vigor of Petunia × hybrida under a variety of abiotic stresses. Petunia mother plants were grown in either a greenhouse during the summer months or an indoor controlled-temperature-and-light environment. Collected seeds were subjected to external stressors, including polyethylene glycol (PEG), sodium chloride (NaCl), high temperature, and abscisic acid (ABA), to determine seed germination percentage and seedling vigor. Results indicated that seeds harvested from the mother plants grown in a controlled environment germinated better than seeds harvested from the mother plants grown in the greenhouse when suboptimal germination conditions were applied. Additionally, the seedlings from the controlled maternal environment performed better in both ABA and salinity stress tests than the greenhouse seedlings. Interestingly, the greenhouse seedlings displayed less reactive oxygen species (ROS) damage and lower electrolyte leakage than the controlled environment seedlings under dehydration stress. The difference in germination and seedling vigor of seeds from the two different maternal environments might be due to the epigenetic memory inherited from the mother plants. This study highlighted the strong impact of the maternal environment on seed germination and seedling vigor in Petunia and may assist in high-quality seed production in ornamental plants.

Highlights

Many ornamental and landscaping plants start their life as seeds, and high-quality seeds are essential for successful plant establishment
Petunia seeds harvested from plants grown in the tent were significantly larger (~15% on average) than seeds harvested from the greenhouse plants (Figure 1)
The germinability of seeds from the greenhouse plants dropped to 61%, 17%, and 11% on 1, 1.5, and 2 μM of abscisic acid (ABA)-infused plates, respectively (Figure 2A,C–E)

Summary

Introduction

Many ornamental and landscaping plants start their life as seeds, and high-quality seeds are essential for successful plant establishment. The environmental cues, including light, temperature, soil moisture, and nutrients, the mother plant encounters can cause variations in seed quality even within the same genotype [4,5,6,7,8,9]. The resulting seed quality variation derived from the maternal effect can shape the phenotypic plasticity of the progeny [1,10]. The benefits of growing the mother plant in favorable environments to obtain higher-quality seeds are well documented and practiced in many crop species, including tomatoes and legumes [2,11,12]. Information about the effects of the maternal environment on the seed and seedling vigor of ornamental plants under abiotic stresses remains scarce

Objectives

Methods

Results