Studies on Selection and Biological Characters of Tomato Indeterminate Growth Habit Mutant Derived from Space Treatment / 航天医学与医学工程

ABSTRACT

Objective To select excellent tomato mutants by space treatment and to cultivate directively new varieties for production application.Method Growth dynamics and change of agricultural characters of the mutant of indeterminate growth habit was observed.And the enzymogram and activity of two kinds of main isoenzyme were analyzed.Result An indeterminate growth habit mutant(M1) which derived from a determinate growth habit cultivar(10-3-2) was obtained from the 1st generation after space treatment(SP_1).Being an inherited character,the indeterminate growth habit of the mutant can be expressed from generation to generation.The plant height of M1 was 145 cm,42.0 cm higher than that of the background one(increased by 29.6%),when the background plant height was determined.The main stem diameter of the mutant was 1.22 cm,0.34 cm thicker than that of background parent.However,there were no visible difference in the fruit size and fruit set percentage between them.The biological characters of M1 and its progenies were studied,and the results showed that the indeterminate growth have no side effects on the agronomic characters and fruit quality,and the mutant had a potentiality of higher yield if the condition is suitable.The activity of two enzymes,SOD and POD,was assayed and there were no obvious difference of SOD activities and enzymograms between the mutant and its background parent,but POD activity was much lower in mutant than that in its background parent.Conclusion After observation through 3 generations,it is found that indetermination growth habit is inheritable and stable.