Systematic selection to adaptive doubled haploid rice lines under different environments of submergence screening methods

Abstract

Climate change can trigger submergence stress, which has an impact on decreasing rice yield and causing crop failure. This needs to be overcome with a sustainable approach, such as breeding doubled-haploid (DH) rice varieties that are adaptive to these stresses. However, it requires a systematic screening approach to solve it. Therefore, this study aimed to select DH rice lines that are tolerant and adaptive through systematic submergence screening and their stability; (2) to identify the effectiveness of both submergence screening environments. The study was carried out in three locations: the greenhouse of ICRR-Muara Bogor, the ICRR-Sukamandi Field Experimental Station, and the IPB-Sawah Baru Experimental Station. The first experiment was conducted in ICRR-Muara using a randomized complete block design (RCBD), with genotype as a factor, consisting of 56 doubled-haploid lines, four commercial varieties, and two check varieties (tolerant and sensitive). Seven selected genotypes representing tolerant, moderate, sensitive, and check groups were transferred into pots in Sawah Baru Experimental Station to be evaluated for agronomic and tolerance responses using the RCBD split-plot design. The second experiment was carried out to validate the stability of tolerance traits in doubled-haploid lines. The trial and the process of the second experiment were like the first experiment (clear water). However, the submergence in the second experiment was conducted using muddy water. The experimental results showed that the screening of concrete pools was effective in determining sensitive lines in large populations. Meanwhile, screening in the pond with muddy water was better in identifying the effect of submergence stress on agronomic and yield characteristics. Based on screening, F13, F14, F15, and F19 are adaptive doubled haploid lines under the systematic screening of submergence stress and have been evaluated for their adaptive and tolerance stability. Therefore, they can be recommended for preliminary yield tests.