Exploring natural diversity for biological nitrogen fixation in maize and its progenitors is a promising approach to reducing our dependence on synthetic fertilizer and enhancing the sustainability of our cropping systems. We have shown previously that maize accessions from the Sierra Mixe can support a nitrogen-fixing community in the mucilage produced by their abundant aerial roots and obtain a significant fraction of their nitrogen from the air through these associations. In this study, we demonstrate that mucilage production depends on root cap and border cells sensing water, as observed in underground roots.
View Article and Find Full Text PDFThe genetic factors underlying changes in ear morphology, and particularly the inheritance of kernel row number (KRN), have been broadly investigated in diverse mapping populations in maize (Zea mays L.). In this study, we mapped a region on the long arm of chromosome 1 containing a QTL for KRN.
View Article and Find Full Text PDFMitochondria are organelles that have their own DNA; serve as the powerhouses of eukaryotic cells; play important roles in stress responses, programmed cell death, and ageing; and in the vast majority of eukaryotes, are maternally transmitted. Strict maternal transmission of mitochondria makes it difficult to select for better-performing mitochondria, or against deleterious mutations in the mitochondrial DNA. Cucumber is a useful plant for organellar genetics because its mitochondria are paternally transmitted and it possesses one of the largest mitochondrial genomes among all eukaryotes.
View Article and Find Full Text PDFThe population genetics of Triatoma dimidiata (Latreille, 1811) from five different provinces in Guatemala, including three sylvan and three domestic populations, was investigated by random amplification of polymorphic DNA-polymerase chain reaction. There is a high degree of genetic variation in all of the T. dimidiata populations as evidenced by high levels of average expected heterozygosity and polymorphism.
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