Patent ID: 7951990

Claim:
A method for producing a hybrid Brassica plant line, comprising the steps of: a) assaying a collection of Brassica inbred plant lines of interest by i) culturing a population of explants of each of said Brassica inbred plant lines of said collection on a medium comprising sucrose or on callus inducing medium comprising sucrose and plant hormones for a period of 0 to 10 days; ii) measuring the electron flow in the mitochondrial electron transport chain in said population of explants, relative to the electron flow in the mitochondrial electron transport chain in a population of explants from a reference plant line of the same species; b) assaying said collection of inbred lines of interest by i) culturing a population of explants of each of said inbred Brassica plant lines of said collection on a medium comprising sucrose or on callus inducing medium comprising sucrose and plant hormones; ii) incubating a first part of each of the populations of said cultured explants in a buffer solution; iii) incubating a second part of each of the populations of said cultured explants in said buffer solution, further comprising a salicylic acid derivative capable of generating oxidative stress in plant cells incubated in a solution of said salicylic acid derivative; iv) measuring the electron flow in the mitochondrial electron transport chain in each of said first and second parts of said populations; c) selecting one inbred plant line which has a higher relative amount of electron flow in the mitochondrial electron transport chain when compared to other inbred lines from said collection as determined in step (a) and which has a negative difference between the measured electron flow in the mitochondrial electron transport chain between said second and said first part as measured in step (b); d) crossing said selected inbred plant line with a second inbred plant line; e) collecting seed from said crossed selected inbred plant line.