Information on Doctoral Thesis of Fellows Le Thi Thanh That

Research title: “Research on Selecting drought-tolerant hybrid maize varieties and identifying farming techniques to  new hybrid maize varieties in Binh Phuoc Province”.

- Specialty: Crop Science

- Code: 62 62 01 10

- PhD. Candidate: Luu Thi Thanh That

- Course duration: 2012 - 2016

- Scientific supervisors:

            1. Dr. Le Quy Kha

            2. Dr. Phan Thi Van

- Training institution:  Thai Nguyen University of Agriculture and Forestry
THE NEW FINDINGS OF DISSERTATION

         Drought tolerance research is conducted on 11 varieties and hybrid maize combinations with 2 control varieties (VN8960 - e / c 1; CP888 - e / c 2) in Dong Phu district and Dong Xoai town, Binh Phuoc province. According to the results of the study, LCH9 variety has been selected  as the best for drought tolerance (Sn = 3292.5; CSH = 0.86 in Dong Xoai and 0.62 in Dong Phu). Crop yield declines due to drought conditions (16.96% in Dong Xoai and 25.33% in Dong Phu).

- The comparison results of 11 varieties and hybrid combinations with 2 control varieties (VN8960 - e / c 1; CP888 - e / c 2) in Summer-Autumn and Autumn-Winter crops in Dong Phu and Dong Xoai showed : Yield of LCH9 variety and hybrid combinations of AG89-TB15 reached from 66.44 to 67.81 quintals/ha and 64.76 to 67.10 quintals/ha. It was higher than 2 control varieties, and the other varieties and hybrid combinations in Summer-Autumn crops in both study sites. In Autumn-Winter crop,  the actual yield of LCH9 and AG89-TB15 was higher than that of the 2 control varieties in Dong Phu. It was similar as the control variety 1 (VN8960) and significantly higher compared to the control variety 2 (CP888) in Dong Xoai.

- In the 5 experimental sites: Dong Xoai, Dong Phu Loc Ninh, Bu Dop, Chon Thanh, LCH9 variety had more stable yield than other varieties and hybrid combinations left (bi = 1,075; S2D = - 3.846).

- The results of the effects of plant spacing and nitrogen doses on the growth and yield of LCH9 variety showed that plant spacing of 60 x 20 cm on the 10 tons of manure + 90 kg P₂O₅ + 90 kg K₂O and nitrogen doseof 200 kg N/ha, LCH9 reached the highest yield and profits.

- Demonstration model was built in Dong Phu district and Dong Xoai Town in 2 crops: Summer-Autumn and Autumn-Winter.  LCH9 variety had a good growth and development, yield reached from 77.19 to 81.4 quintals/ha, profits rate reached from 40.74 to 43.81%, it was higher than CP888 variety commonly used  at Binh Phuoc in the 2 crops in 2 study sites.

PRACTICAL APPLICABILITY AND THE NEEDS FOR FURTHER STUDIES:

            * Practical applicability:

- The results of the study have selected LCH9 variety and AG89-TB15 hybrid combinations, which can be drought-tolerant withhigh and stable yield that can be used for maize production in Binh Phuoc province.

- Identifyingplant spacing and suitable N levels for LCH9 variety in Binh Phuoc in order to reach the best yield and production efficiency.

- The findings of the study was an important argument for the study of the growth, development, drought tolerance, plant spacing and N levels to maize.

- The findings of the study was a significant reference for teaching and learning of maize

   * Opening issues for further studies:

   - It is recommended that other studies should focus on phosphorus and potassium levels and crop seasons to improve the process of farming techniques for LCH9 in Binh Phuoc.