Accelerated aging predicts the emergence of rice seedlings in the field

Abstract

Selecting the most appropriate vigor test for rice to predict seedling emergence remains a challenge. This is mainly attributed to the diversity of available tests that evaluate vigor; however, there is a critical need for tests that can show a high correlation with field emergence. Thus, this study aimed to determine which vigor tests are the most efficient in predicting the emergence of rice seedlings, to facilitate correct selection for quality control analyses and pre-sowing for rice seed commercialization. Across two growing seasons, 2016/17 and 2017/18, different seed lots of ‘SCS122 Miura’ rice were subjected to vigor evaluations including germination test, electrical conductivity, cold test, low temperature germination, accelerated aging, root and shoot length, seedling dry weight, emergence speed, and emergence speed index, and greenhouse and field emergence tests. A completely randomized design with four replicates was used for the experiments. All statistical analyses were performed using R software. The germination rate for ‘SCS122 Miura’ seed lots in both growing seasons was greater than 80%. In both growing seasons, unlike the similar results obtained for field emergence, in the laboratory tests, differences were observed between these same seed lots. Electrical conductivity and emergence speed showed a negative correlation with greenhouse and field emergence. The vigor tests for accelerated aging, emergence speed, and dry weight are more efficient in predicting the emergence of rice seedlings. Among the tested methods, accelerated aging (41 °C for 120 h) is one of the most efficient for predicting the emergence of rice seedlings and the best option for laboratory analysis of quality control and pre-sowing owing to its practicality and time required for execution.

Sowing density adjustment by rice seed vigor

“…Similarly, in the 2020/2021 growing season, the high-vigor lots presented an average vigor by AA percentage of 90%, which was significantly higher (p < 0.05) than the vigor by AA obtained for the low-vigor lots (64%) (Table 1). According to the literature, vigor by AA presents a high correlation with seedling emergence in the field and is, therefore, considered one of the most efficient parameters for predicting seedling emergence (Garcia;Coelho, 2021). This is because vigor by AA simulates, in the laboratory, the adverse conditions that the seeds would encounter in the field at the time of emergence.…”

“…This difference in the performance of seedlings between the lots with contrasting vigor was also reported by Abati et al (2018) and Marinho et al (2021), who observed, in separate studies conducted on wheat, that the use of vigorous seeds resulted in a greater number of emerged seedlings compared to the use of non-vigorous seeds. This is because high-vigor seeds have a higher rate of seedling development in the field, even under unfavorable conditions, which results in an adequate initial establishment (Carvalho;Nakagawa, 2012;Garcia;Coelho, 2021).…”