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In Extended Data Fig. 1 of this Article, the labels ‘Market class’ and ‘Biological status’ were inadvertently swapped. In the corresponding figure legend, “Track 1: Biological status; Track 2: Market class;” should have been “Track 1: Market class; Track 2: Biological status;”. The original Article has been corrected online.

In Extended Data Fig. 1 of this Article, the labels ‘Market class’ and ‘Biological status’ were inadvertently swapped. In the corresponding figure legend, “Track 1: Biological status; Track 2: Market class;” should have been “Track 1: Market class; Track 2: Biological status;”. The original Article has been corrected online.

To the Editor...

Crop production systems need to expand their outputs sustainably to feed a burgeoning human population. Advances in genome sequencing technologies combined with efficient trait mapping procedures accelerate the availability of beneficial alleles for breeding and research. Enhanced interoperability between different omics and phenotyping platforms, leveraged by evolving machine learning tools, will help provide mechanistic explanations for complex plant traits. Targeted and rapid assembly of beneficial alleles using optimized breeding strategies and precise genome editing techniques could deliver ideal crops for the future. Realizing desired productivity gains in the field is imperative for securing an adequate future food supply for 10 billion people.

Zero hunger and good health could be realized by 2030 through effective conservation, characterization and utilization of germplasm resources1. So far, few chickpea (Cicer arietinum) germplasm accessions have been characterized at the genome sequence level2. Here we present a detailed map of variation in 3,171 cultivated and 195 wild accessions to provide publicly available resources for chickpea genomics research and breeding. We constructed a chickpea pan-genome to describe genomic diversity across cultivated chickpea and its wild progenitor accessions. A divergence tree using genes present in around 80% of individuals in one species allowed us to estimate the divergence of Cicer over the last 21 million years. Our analysis found chromosomal segments and genes that show signatures of selection during domestication, migration and improvement. The chromosomal locations of deleterious mutations responsible for limited genetic diversity and decreased fitness were identified in elite germplasm. We identified superior haplotypes for improvement-related traits in landraces that can be introgressed into elite breeding lines through haplotype-based breeding, and found targets for purging deleterious alleles through genomics-assisted breeding and/or gene editing. Finally, we propose three crop breeding strategies based on genomic prediction to enhance crop productivity for 16 traits while avoiding the erosion of genetic diversity through optimal contribution selection (OCS)-based pre-breeding. The predicted performance for 100-seed weight, an important yield-related trait, increased by up to 23% and 12% with OCS- and haplotype-based genomic approaches, respectively.

To the Editor...

Key message: QTL mapping identified key genomic regions associated with adult-plant resistance to tan spot, which are effective even in the presence of the sensitivity gene Tsn1, thus serving as a new genetic solution to develop disease-resistant wheat cultivars. Abstract: Improving resistance to tan spot (Pyrenophora tritici-repentis; Ptr) in wheat by eliminating race-specific susceptibility genes is a common breeding approach worldwide. The potential to exploit variation in quantitative forms of resistance, such as adult-plant resistance (APR), offers an alternative approach that could lead to broad-spectrum protection. We previously identified wheat landraces in the Vavilov diversity panel that exhibited high levels of APR despite carrying the sensitivity gene Tsn1. In this study, we characterised the genetic control of APR by developing a recombinant inbred line population fixed for Tsn1, but segregating for the APR trait. Linkage mapping using DArTseq markers and disease response phenotypes identified a QTL associated with APR to Ptr race 1 (producing Ptr ToxA- and Ptr ToxC) on chromosome 2B (Qts.313-2B), which was consistently detected in multiple adult-plant experiments. Additional loci were also detected on chromosomes 2A, 3D, 5A, 5D, 6A, 6B and 7A at the seedling stage, and on chromosomes 1A and 5B at the adult stage. We demonstrate that Qts.313-2B can be combined with other adult-plant QTL (i.e. Qts.313-1A and Qts.313-5B) to strengthen resistance levels. The APR QTL reported in this study provide a new genetic solution to tan spot in Australia and could be deployed in wheat cultivars, even in the presence of Tsn1, to decrease production losses and reduce the application of fungicides

Pure line breeding is a resource-intensive activity that takes 10 years or more to develop a new cultivar. In some crops, conducting off-season nurseries has significantly reduced the length of the breeding cycle. This approach could not be exploited in pigeonpea [Cajanus cajan (L.) Millsp.], because traditionally it has been a photoperiod-sensitive crop that requires long periods of darkness to induce flowering. However, the recent success of breeding early maturing photoperiod-insensitive genotypes has opened up the possibility of adopting ‘speed breeding’ techniques to enable rapid generation turnover. This paper outlines a speed breeding approach that integrates the use of immature seed germination for rapid generation advancement and a “single pod descent” method of breeding. To accelerate line development, while conserving genetic variability, the approach permits four generations per year and can fast-track field evaluation of resulting homozygous lines. Therefore, the breeding strategy conserves resources and has potential to deliver new early maturing cultivars within a substantially reduced timeframe of 4–5 years.

New Breeding Technologies? For some, both inside and outside the scientific community, this phrase is synonymous with gene editing—or used exclusively to describe the application of CRISPR/Cas9 to plant improvement. Much as, historically, the term ‘biotech crops’ has been hijacked to only mean crop plants produced using genetic engineering.

New Breeding Technologies? For some, both inside and outside the scientific community, this phrase is synonymous with gene editing—or used exclusively to describe the application of CRISPR/Cas9 to plant improvement. Much as, historically, the term ‘biotech crops’ has been hijacked to only mean crop plants produced using genetic engineering.

Pure line breeding is a resource-intensive activity that takes 10 years or more to develop a new cultivar. In some crops, conducting off-season nurseries has significantly reduced the length of the breeding cycle. This approach could not be exploited in pigeonpea [Cajanus cajan (L.) Millsp.], because traditionally it has been a photoperiod-sensitive crop that requires long periods of darkness to induce flowering. However, the recent success of breeding early maturing photoperiod-insensitive genotypes has opened up the possibility of adopting ‘speed breeding’ techniques to enable rapid generation turnover. This paper outlines a speed breeding approach that integrates the use of immature seed germination for rapid generation advancement and a “single pod descent” method of breeding. To accelerate line development, while conserving genetic variability, the approach permits four generations per year and can fast-track field evaluation of resulting homozygous lines. Therefore, the breeding strategy conserves resources and has potential to deliver new early maturing cultivars within a substantially reduced timeframe of 4–5 years.