Study On The Relationship Between Lodging Resistance And Plant Characters Of Different Tartary Buckwheat

Lodging is one of the limiting factors of Tartary Buckwheat high production and high quality. It is significant to define related indexes of lodging and to screen high lodging resistance cultivars for implement technology of lodging resistance cultivation. Twenty cultivars of Tartary Buckwheat widely planted was studied as materials. Related lodging indexes were systematically researched in two ecology spots of Bijie, Guizhou(G-BJ) and Jintang, Sichuan(S-JT). Including plant agronomic traits, stem strength, physiological and biochemical properties. An analysis of the differences in cultivars lodging resistance. Defined the related indexes of Tartary Buckwheat lodging. The main results were as follows:1.The difference in Tartary Buckwheat agronomic characteristicsIt showed that significant differences in plant height, height of gravity center of cultivars. Also, there are inconsistent representation trends of these indexs in S-JT and G-BJ. In S-JT, it showed that highly performed cultivars were Blackfeng No.1, Tongliao Buckwheat, Dianning No.1 and Jinku No.2. The height was more than 80.00 cm and the height of gravity center was over 32.00 cm. While, showing relatively low cultivars were Chuanqiao No.1, Westqiao No.1. In G-BJ, it showed that highly performed cultivars were Chuanqiao No.1, Daan Ben, Yunqiao No.2, Jiujiang Buckwheat. Miqiao No.1 was the lowest one. In both eco-spots, Daan Ben had significantly more node numbers of main stem than Jinku No.6.There were also significant differences in stem basal internode length and diameter. The performance high cultivars in basal internode length were almost the same as in plant height. It was non-identical with the basal internode diameter in two ecology spots. In S-JT, had high cultivars in each basal internode diameter were Blackfeng No.1, Miqiao No.1, Westqiao No.1. Meanwhile, the second internode diameter of Phoenix Buckwheat was the lowest one(4.37mm). Other internode of Jiujiang Buckwheat showed the lowest diameter in S-JT. In G-BJ, the basal internode diameter of Haizi Ge was significantly higher than other cultivars. Chuanqiao No.1 showed low, which average diameter was 3.89 mm.2.The differences in Tartary Buckwheat stem material propertiesRoot dry weight, stem dry weight, leaf dry weight, basal internode dry weight were studied to represent the stem material properties. Selected cultivars had significant differences in these indexes. Haizi Ge buckwheat grown in both of eco-spots performed highly in dry weight of root and stem. While, the basal internode dry weight performance trends were inconsistent of each eco-spot. The Chuanqiao No.1 and Jinqiao No.6 basal internode dry weight performed well in S-JT. While, Miqiao No.1 performed badly in the same place. Chuanqiao No.1 and Eji Buckwheat had low performance of the basal internode dry weight in G-BJ. While, Chuanqiao No.1 was lower than the others in G-BJ.3.The differences in Tartary Buckwheat mechanical characteristicsMechanical strength and puncture strength of basal stem internode were studied to represent stem mechanical characteristics. There were significant differences in the mechanical strength and puncture strength of basal stem internode. Mechanical strength of Miqiao No.1, Yunqiao No.2 etc and puncture strength of Qianku No.5 had high performance in S-JT, while mechianical strength of Haizi Ge, puncture strength of Jinku No.6 and other had low performance. Both basal stem mechanical and puncture strength of Chuanqiao No.1 showed lower in G-BJ.4.The differences in Tartary Buckwheat physiological charateristicsThere were obvious differences in stem lignin, cellulose content. The stem lignin content of Yunqiao No.2 was high in both ecological spots. It was respectively 20.28% in S-JT and 21% in G-BJ. Low lignin content cultivars were Daan Ben buckwheat, Eji Buckwheat grown in S-JT and Chuanqiao No.1, Jiujiang Buckwheat grown in G-BJ. There were significant differences in the content of stem cellulose. The tendency of different cultivars cellulose contents was the same as the tendency of cultivars lignin contents in two eco-spots.Differences also existed in content of stalk soluble sugar, nitrogen, potassium and other mineral elements. In both eco-spots, stem soluble sugar content of Phoenix Buckwheat was significantly higher than other cultivars. Cultivars with high content of nitrogen,calcium, silicon were respectively Miqiao No.1, Liuku No.3, Daan Ben buckwheat. The tendency of different cultivars stem potassium content was incosistency. In S-JT, Jinku No.6, Yunnan Buckwheat showed highly in potassium content. Their contents were both higher than Qianku No.5’s. In G-BJ, Chuanqiao No.2 had the highest stem potassium content(0.80%), While Chuanqiao No.1 obviously lower than other cultivars(0.52%).5.Differences in Tartary Buckwheat lodging percentageYunqiao No.2 had the lowest lodging percentage in both eco-spots. There was 12.6% in S-JT and 24.36% in G-BJ. In addition, in both eco-spots,Phoenix Buckwheat also had low lodging percentage.Blackfeng No.1, Jinku No.2, Eji Buckwheat had high lodging percentage. Westqiao No.3, Chuanqiao No.2, Liuku No.3 and Yunnan Buckwheat had medium lodging percentage.6.The relationship between lodging Resistance and plant charactersIn S-JT, it was significantly positive correlation between lodging percentage and the second internode length, the correlation coefficient was 0.455. While, the cotyledon internode puncture strength and its dry weight, the first and second internode mechanical strength, content of stem lignin, cellulose were negative correlated with lodging percentage. Correlated results of G-BJ were roughly the same. In this study, the key indexes to evaluate the lodging resistance of Tartary Buckwheat were determined preliminarily. There were the content of stem lignin, cellulose, stem mechanical strength of the first and second internode, dry weight and puncture strength of the cotyledon internode.