Study on the Index of Cassava Seed Stem Vigor

Purpose Seed stem quality is the main restriction for cassava yield. There will be provided theoretical reference for the cassava seed stem treatment through research on simple, rapid and accurate index for the seed stem vigor.

Method Two cassava varieties of SC8 and NZ199 were selected for test. To obtain different vigor seed stems, the samples were collected on the 150, 180, 210, 240, 270 and 300 days after planting. The seed stem germination test was carried out under normal and drought stress conditions to obtain germination indexes, and determinate physiology and biochemistry indexes before germination. The comprehensive vigor scores were investigated by the principal component analysis, then the correlation analysis was carried out between the physiological and biochemical indexes and the comprehensive vigor scores.

Result The comprehensive vigor scores of 6 samples were different. The comprehensive vigor scores were significantly negatively correlated with MDA content also water content (P<0.05), and extremely significant positive correlation with starch content (P<0.01), significant positive correlation with soluble protein content and free proline content in the seed stem of SC8 (P<0.05). The comprehensive vigor scores was extremely significant negative correlation with the MDA content (P<0.01), without significant but higher correlation with the CAT activity, starch content, free proline content and water content in the seed stem of NZ199 (P>0.05).

Conclusion We recommended the MDA content as the evaluation index of cassava seed stem vigor.