Application of Computer Vision Technique to Maize Variety Identification

Variety identification is important for maize breeding, processing and trade. The computer vision technique has been widely applied to maize variety identification. In this paper, computer vision technique has been summarized from the following technical aspects including image acquisition, image processing, characteristic parameter extraction, pattern recognition and programming softwares. In addition, the existing problems during the application of this technique to maize variety identification have also been analyzed and its development tendency is forecasted.

Drought Resistance of Eight Maize Varieties at Seedling Stage in Yunnan Province

Using eight maize varieties （Tiannuo 888, Yunnuo 6, Yunrui 999, Yunrui 6, Yunrui 47, Yunrui 88, Yunyou 105, Yuntianyun 2） as the research ma- terials, this paper aimed to figure out the possible influence caused by repeated drought treatment. A pot experiment was conducted to investigate the changes in 13 phenotypic characters and physiological and biochemical indexes （plant height, fresh mass, root shoot ratio, POD activity, SOD activity） related to drought resist- ante, under two levels of water supply （repeated drought treatment and CK） at seedling stage of maize varieties, and evaluated drought resistanee comprehensively by standard deviation coefficient allocation weighed method. The results showed that the survival rate, leaf area, plant height, shoot fresh mass, root fresh mass, shoot dry mass and root dry mass of seedling maize decreased at varying degrees after repeated drought stress. However, the MDA molality, root shoot ratio, Pro content and soluble protein content increased under repeated drought stress. There were significant difference in morphological, physiological and biochemical inde- xes among different maize varieties. The drought resistances of different maize varieties successively were Yunrui 47 〉 Yuntianyu 2 〉 Yunyou 105 〉 Yunnuo 6 〉 Tianuo 888 〉 Yunrui 6 〉 Yunrui 999 〉 Yunrui 88. These results provide references for maize drought-resistant breeding and maize production.

Screening Test of Maize Varieties in Mountainous Arid Areas

Drought and water shortage are the biggest limiting factors of dry farming,and variety plays an important role in an increase in the yield of dryland maize.Screening high-yield maize varieties is helpful to the continuous increase and stable yield of dryland grain.In this experiment,the growth period,characters and yield of 12 maize varieties were analyzed.The results show that the yield of Ganyu series was low,while the yield of Lianda 169 was the highest(8 080.93 kg/ha),which was 31.40% higher than Jinsui 4.The yield of Dunyu 16 was6 621.06 kg/ha,7.64% higher than Jinsui 4.The two varieties had good comprehensive characters,so they could be popularized and planted in dry farming areas of Lanzhou City.