Plant breeding can be made more efficient by having fewer, better crosses

J. R. Witcombe, S. Gyawali, Madhu Subedi, D. S. Virk, Krishna D. Joshi

Research output: Contribution to journalArticlepeer-review

26 Citations (SciVal)
121 Downloads (Pure)


Crop yields have to increase to provide food security for the world’s growing population. To achieve these yield increases there will have to be a significant contribution from genetic gains made by conventional plant
breeding. However, the breeding process is not efficient because crosses made between parental combinations that fail to produce useful varieties consume over 99% of the resources.

We tested in a rice-breeding programme if its efficiency could be improved by using many fewer, but more judiciously chosen crosses than usual. In a 15-year programme in Nepal, with varietal testing also in India and
Bangladesh, we made only six crosses that were stringently chosen on complementary parental performance. We evaluated their success by the adoption and official release of the varieties they produced. We then modelled
optimum cross number using assumptions based on our experimental results.
Four of the six crosses succeeded. This was a fifty-fold improvement over breeding programmes that employ many crosses where only about one, or fewer, crosses in 200 succeed. Based on these results, we modelled the optimum number of crosses by assuming there would be a decline in the reliability of the breeder’s prediction of the value of each cross as more crosses were made (because there is progressively less information on the traits of the parents). Fewer-cross programmes were more likely to succeed and did so using fewer resources. Making more crosses reduced the overall probability of success of the breeding programme.

The efficiency of national and international breeding programmes would be increased by making fewer crosses among more carefully chosen parents. This would increase the number of higher yielding varieties that are
delivered to farmers and hence help to improve food security.
Original languageEnglish
Article number22
Number of pages12
JournalBMC Plant Biology
Publication statusPublished - Feb 2013


Dive into the research topics of 'Plant breeding can be made more efficient by having fewer, better crosses'. Together they form a unique fingerprint.

Cite this