The Effects Of CO₂ Laser Irradiation On The Growth And Physiology Of Soybean And Corn

Using corn (Zea mays L.) and soybean (Glycine max Merr) as the experimental material in this paper, we use CO2 laser to radiate on the soybean and corn wet seeds and then observe the effects of seedlings development in the experiments. The findings are:(1) After the CO2 laser with different power density (16mw/mm2, 18mw/mm2, 20mw/mm2) radiates on the soybean seeds, compared with control, the treatment of 18mw/mm2 is the best one among three treatments. After the soybean was radiated with five different length of time (45s, 60s, 75s, 90s, 105s), the treatment of 75s is the best one among five treatments.(2) After different power density CO2 laser radiated on the soybeans, all treatments show that soybean morphological indexes such as germination capability, plant high, plant diameter, 100 seeds weight were increased. After different time of radiation on the soybeans, morphological indexes also were improved. The best was 75s.(3) After different power density CO2 laser radiated on the soybeans, compared with the control, the indexes such as soluble protein content, soluble saccharine content, amino acid content and amylase activity increased. The treatment of 18mw/mm2 is the best. After different time of radiation on the soybeans, above of indexes were also improved. We found that 75s was the best one among five treatments. When the time limit was longer or shorter than it, these indexes would come down. Especially when the radiation time was too long (105s), CO2 laser radiation would have negative effects on soybean.(4) After different power density CO2 laser radiated on the soybeans, chlorophyll content rose. At the same time, the photosynthetic rate (Pn) ascent and stomatal conductance descent of soybean have also promoted the water use efficiency (WUE). The treatment of 18mw/mm2 is the best. After different time of radiation on the soybeans, photosynthesis ability was improved, too. The treatment of 75s is the best one.(5) We chose 3 different time limits (30s, 60s, 90s). After different time of radiation (the treatment of 18mw/mm2) on wet corn seeds, compared with control, the treatment of 60s is the best one among three treatments.(6) The corn morphological indexes such as germination capability, plant high, plant diameter, 100 seeds weight were increased under different time CO2 laser treatment. With the development of corn seedlings, the increase extent grew bigger. The treatment of 60s is the best.(7) After different time of radiation on the corn seeds, the indexes such as soluble protein content, soluble saccharine content and amino acid content increased; Amylase and protease activities rose. The effects of the 30s' treatment is small, others' treatment effects are bigger than the control.(8) Under the treatment of different time radiation on the corn seeds, antioxidative enzymes SOD, POD and CAT activities rose; Vc content increased. These indexes increased the capable of scavenge of superoxide radical mechanism which made plants be able to grow normally.(9) After different time of radiation on the corn seeds, chlorophyll content rose. The photosynthetic rate (Pn) ascent and stomatal conductance descent made the water use efficiency higher.The conclusions of this paper are the primary results, which have some application values in product.