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Global cropland expansion has been recognized as a key driver of food security. However, cropland expansion induced alterations in biophysical properties of the Earth's surface and greenhouse gas emissions may potentially impact the Earth's climate system. These changes could, in turn, affect cropland productivity and the potential distribution of croplands, although the underlying mechanisms remain relatively underexplored. In this study, a global climate model was employed to quantify the impact of global cropland expansion on cropping potential, utilizing observed and derived cropland expansion data. Our findings reveal that since 10000 BC, a 28% increase in cropland expansion has led to a 1.2% enhancement in global cropping potential, owing to more favorable precipitation and temperature conditions. This suggests that global cropland expansion yields dual benefits to crop production. However, in regions with low growth rates of cropping potential, cropland expansion proves to be an inefficient method for augmenting local crop potential yield. As croplands continue to expand worldwide, the capacity to support populations in different regions is altered, thereby reducing cropping potential inequality among nations. [ABSTRACT FROM AUTHOR]

Cabbage has significant heterosis and most commercial cultivars are hybrids. To explore genetic basis of cabbage heterosis and promote cabbage heterosis utilization, we constructed two populations by crossing 100 DH lines derived from a cabbage hybrid 01-20 ×96-100 with two female parents. Hybrids exhibited different extents of heterosis, the mean value of economic yield was 2.6 times bigger than parents. We identified 66 and 73 QTLs associated with mid-parent heterosis and transgressive heterosis of twelve yield-related traits, respectively. Some QTLs could be detected under the two-year experiment existed in two populations with different testers, showing relatively high phenotypic contribution rate (15.8%-20.0%). Heterosis QTLs exhibited clustered distribution in several cabbage chromosome regions. Two dominant genetic regions, mk300-316 and mk258-268, originated from the elite parent 01-20, exhibited significant genetic effects for yield-related heterosis, which were first identified. Three elite DH lines (D22, D46, D83) harboring these two dominant regions were selected as having strong heterosis in cabbage production. Candidate gene analysis revealed that some genes participating in biosynthetic processes of carbohydrates and some responses to auxin might affect cabbage yield heterosis. QTL identification and genetic dissection of yield-related traits provide new insights into the genetic effects of cabbage heterosis. [ABSTRACT FROM AUTHOR]