Researchers from the University of Milan developed protocols for genetic
transformation of African
varieties to enable the use of CRISPR-Cas9.
African Oryza glaberrima and Oryza sativa are known to be valuable sources
of favorable Traits because of their adaptation to the continent's extreme
environmental conditions. These varieties exhibit superior resistance to
endemic pests and tolerance to drought and nutrient deficiencies compared to
Asian rice varieties. However, "domestication traits" including seed
shattering, lodging, and seed yield are not well established in these
African landraces. Thus, the use of these African varieties for high
production agriculture is limited by unpredictable yield and grain quality.
To address this concern, the researchers developed protocols for the
improvement of the African rice landraces using CRISPR-Cas9.
As proof of concept, they used African landrace Kabre to target the
"domestication loci" and enhance its agronomic potential. Genetic
transformation with CRISPR-Cas9-based vectors led to single and simultaneous
several gene knockouts. Plants with reduced height to decrease lodging were
generated by disrupting the HTD1 gene. The researchers detected three loci
that control seed size and/or yield then targeted them using a multiplex
CRISPR-Cas9 construct. This led to mutants with significantly enhanced seed