Effects Of Zinc On The Germination And Growth Of Different Genotype Maize Seedlings

This study was based on the selection of20maize hybrids suitable in the vast areas of Heilongjiang inrecent years. Through the water culture experiments made separately with zinc efficiency reflected in variousgenotype maize, the two hybrids sensitive to the zinc differently were screened and identified to researchfurther, including Tiannong Jiu (zinc deficiency insensitive) and Xinyu9(zinc deficiency sensitive). Exploredthe effects of zinc on seed germination and seeding stage of different genotypes maize. Key findings were asfollowed:Significant differences existed in zinc nutrition of the different genotypes maize, and the optimum zincconcentration of maize seedling is0.1~1.0μmol·L-1, the low-level zinc (0~0.01μmol·L-1) and high-level zinc(10~100μmol·L-1) would repress maize growth. The native zinc content from maize of different genotypesvaried greatly, since the zinc absorbing ability of maize was different. The maize plants have the ability tochoose the transport, when dealing with excessive amounts of zinc do harm to the seedlings, the zinc absorbedby the roots transport to the ground in proportion, then retard the harm to the aboveground for the excessivezinc ions.According to the zinc efficiency of different genotype maize seedlings, using the cluster analysis to dividethe20varieties of maize into three groups, they are zinc deficiency sensitive type, zinc deficiency insensitivetype and medium sensitive respectively. According to the performance of different genotype maize in the test,select Tiannong Jiu (zinc deficiency insensitive) and Xinyu9(zinc deficiency sensitive) as the material for thefurther mechanism research.The different genotype maize seeds treated with appropriate concentration of zinc, the germination andgrowth all get promote. The zinc concentration of50~100μmol·L-1processing soaked with the seed have themost significant effects. While the high-level zinc concentration is toxic to the maize seedlings and inhibit theirgrowth. The effects of zinc on the α-amylase activity of maize seed will be restrained, with the increasing ofzinc concentration the inhibition enhanced gradually. With the increasing of zinc concent in the treatment, theZn content of different genotype maize germs and radicles increased significant. With the increasing of zincconcent in the treatment, the growth changes of Xinyu9(zinc deficiency sensitive) are more significant thanTiannong Jiu (zinc deficiency insensitive).The different concentrations of zinc treatment have significant physiological characters impact on maizeseedlings. When the zinc concent of treatment is between0.1and1.0μmol·L-1, the accumulation of photosynthetic product and nitrogen metabolism are increased in different genotype maize seedlings, theprotective enzyme activity of leaf is also increased, and promote the growth of maize seedlings. Low-level zinc(0~0.01μmol·L-1) and high-level zinc (10~100μmol·L-1) both have inhibitory effects on the accumulation ofphotosynthetic product of maize seedlings and nitrogen metabolism. As the increasing of zinc concentration inthe treatment, the change of the indicators in Xinyu9(zinc deficiency sensitive) is more significant thanTiannong Jiu (zinc deficiency insensitive), Xinyu9is more sensitive to zinc.