  Irradiation breeding is an important technique in the effort to solve food
shortages and improve the quality of agricultural products. In this study, a
field test was implemented on the M3 generation of two mutant pea plants gained
from previous neutron radiation of pea seeds. The relationship between
agronomic characteristics and yields of the mutants was investigated. Moreover,
differences in physiological and biochemical properties and seed nutrients were
analyzed. The results demonstrated that the plant height, effective pods per
plant, and yield per plant of mutant Leaf-M1 were 45.0%, 43.2%, and 50.9%
higher than those of the control group. Further analysis attributed the
increase in yield per plant to the increased branching number. The yield per
plant of mutant Leaf-M2 was 7.8% higher than that of the control group, which
could be related with the increased chlorophyll content in the leaves. There
was a significant difference between the two mutants in the increase of yield
per plant owing to morphological variation between the two mutants. There were
significant differences in SOD activity and MDA content between the two mutants
and the control, indicating that the physiological regulation of the two
mutants also changed. In addition, the iron element content of seeds of the two
mutants were about 10.9% lower than in the seeds of the control group, a
significant difference. These findings indicate that the mutants Leaf-M1 and
Leaf-M2 have breeding value and material value for molecular biological
studies.
