Generating Useful Genetic Variation in Crops by Induced Mutation, Volume II

Editors

Apichart Vanavichit

Kasetsart University

Antonio Costa De Oliveira

Federal University of Pelotas

Baltazar Antonio

Japan International Research Center for Agricultural Sciences (JIRCAS)

Impact

Manhattan and QQ plots for isoflavone contents in 2020 in the MDP using MLM and mrMLM.

Original Research

18 August 2022

Genome wide association study to detect genetic regions related to isoflavone content in a mutant soybean population derived from radiation breeding

Jung Min Kim

, 8 more and

Soon-Jae Kwon

3,927 views

9 citations

Grain phenotypic analysis and sequence analysis of CRISPR/Cas9-induced knockout yel mutants generated by targeting OsCOP10 and OsDDB1 genes. (A,B) Grain phenotype of Dongjin (WT) seeds and CRISPR mutant seeds generated by targeting OsCOP10 (A) and OsDDB1 (B). Grains showing the yel phenotype were randomly selected from each positive T0 transgenic plant. (C) Sequence comparison of OsCOP10 (LOC_Os07g38940/Os07g0577400) and OsDDB1 (LOC_Os05g51480/Os05g0592400) target regions in the WT and mutants. The first exon of OsCOP10 and second exon of OsDDB1 were targeted to induce mutations. Red dashes and letters indicate deletions and insertions, respectively, in transgenic lines. Black and green letters indicate the target sequence and PAM, respectively. Mutation types are shown to the right of each mutated sequence (-, deletion; +, insertion).

Original Research

25 July 2022

Mutations in OsDET1, OsCOP10, and OsDDB1 confer embryonic lethality and alter flavonoid accumulation in Rice (Oryza sativa L.) seed

Backki Kim

, 7 more and

Hee-Jong Koh

4,726 views

3 citations

Mean values of branches per plant (BPP), pods per plant (PPP), plant yield (PY), nitrate reductase activity (NRA), chlorophyll (CHL), carotenoids (CARO), proteins (PRO), iron (Fe), copper (Cu), zinc (Zn) in 11 M4 high yielding mutant lines and two control plants (n = 30). Measurement unit for NRA (nmol h−1 g−1 FW); CHL (mg g−1 FW); CARO (mg g−1 FW); PRO (%); Fe (mg 100 g−1); Co (mg 100 g−1); Zn (mg 100 g−1) (Source: Data adapted from Raina et al., 2020. http://creativecommons.org/licenses/by/4.0/).

Original Research

14 June 2022

Gamma Rays and Sodium Azide Induced Genetic Variability in High-Yielding and Biofortified Mutant Lines in Cowpea [Vigna unguiculata (L.) Walp.]

Aamir Raina

, 4 more and

Samiullah Khan

3,371 views

35 citations

Original Research

25 May 2022

Induced Genetic Variations in Stomatal Density and Size of Rice Strongly Affects Water Use Efficiency and Responses to Drought Stresses

Mutiara K. Pitaloka

, 11 more and

Apichart Vanavichit

Rice (Oryza sativa L.) is an important food crop relied upon by billions of people worldwide. However, with increasing pressure from climate change and rapid population growth, cultivation is very water-intensive. Therefore, it is critical to produce rice that is high-yielding and genetically more water-use efficient. Here, using the stabilized fast-neutron mutagenized population of Jao Hom Nin (JHN) - a popular purple rice cultivar - we microscopically examined hundreds of flag leaves to identify four stomatal model mutants with either high density (HD) or low density (LD) stomata, and small-sized (SS) or large-sized (LS) stomata. With similar genetic background and uniformity, the stomatal model mutants were used to understand the role of stomatal variants on physiological responses to abiotic stress. Our results show that SS and HD respond better to increasing CO2 concentration and HD has higher stomatal conductance (gs) compared to the other stomatal model mutants, although the effects on gas exchange or overall plant performance were small under greenhouse conditions. In addition, the results of our drought experiments suggest that LD and SS can better adapt to restricted water conditions, and LD showed higher water use efficiency (WUE) and biomass/plant than other stomatal model mutants under long-term restricted water treatment. Finally, our study suggests that reducing stomata density and size may play a promising role for further work on developing a climate-ready rice variety to adapt to drought and heat stress. We propose that low stomata density and small size have high potential as genetic donors for improving WUE in climate-ready rice.

8,357 views

43 citations

Original Research

11 January 2022

Identification of the Q Gene Playing a Role in Spike Morphology Variation in Wheat Mutants and Its Regulatory Network

Jiazi Zhang

, 9 more and

Luxiang Liu

The wheat AP2 family gene Q controls domestication traits, including spike morphology and threshability, which are critical for the widespread cultivation and yield improvement of wheat. Although many studies have investigated the molecular mechanisms of the Q gene, its direct target genes, especially those controlling spike morphology, are not clear, and its regulatory pathways are not well established. In this study, we conducted gene mapping of a wheat speltoid spike mutant and found that a new allele of the Q gene with protein truncation played a role in spike morphology variation in the mutant. Dynamic expression levels of the Q gene throughout the spike development process suggested that the transcript abundances of the mutant were decreased at the W6 and W7 scales compared to those of the WT. We identified several mutation sites on the Q gene and showed that mutations in different domains resulted in distinct phenotypes. In addition, we found that the Q gene produced three transcripts via alternative splicing and that they exhibited differential expression patterns in nodes, internodes, flag leaves, and spikes. Finally, we identified several target genes directly downstream of Q, including TaGRF1-2D and TaMGD-6B, and proposed a possible regulatory network. This study uncovered the target genes of Q, and the results can help to clarify the mechanism of wheat spike morphology and thereby improve wheat grain yield.