Acta Agriculturae Zhejiangensis ›› 2020, Vol. 32 ›› Issue (12): 2111-2118.DOI: 10.3969/j.issn.1004-1524.2020.12.01

• Crop Science • Previous Articles     Next Articles

Effects of reduced chemical nitrogen and organic manure substitution on potato root morphology and yield

HAN Tiqian1(), LIU Zhen2,3, LIU Yuhui2, ZHANG Xiaojing4, WANG Li1,2,*(), ZHANG Junlian2,3,*()   

  1. 1. College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
    2. Gansu Provincial Key Laboratory of Aridland Crop Science/Gansu Key Laboratory of Crop Genetic and Germplasm Enhancement, Gansu Agricultural University, Lanzhou 730070, China
    3. College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China
    4. Dingxi Academy of Agricultural Sciences, Dingxi 743000, China
  • Received:2020-04-14 Online:2020-12-25 Published:2020-12-25
  • Contact: WANG Li,ZHANG Junlian

Abstract:

Field experiments were conducted to study the effects of reduced chemical nitrogen and organic manure substitution on root growth in different developmental stages and yield of potato in the semi-arid area under film drip irrigation, in order to provide an efficient nitrogen management method in the cultivation of potato. Potato cultivar Qingshu9 was used in the test. The conventional N rate of 225 kg·hm-2 was used as the control (CK), 70% chemical nitrogen fertilizer (RN) and 50% chemical nitrogen fertilizer (LN) were set up for reduced chemical nitrogen application treatments, and 80% chemical nitrogen fertilizer+20% organic nitrogen manure (LO) and 60% chemical nitrogen fertilizer+40% organic nitrogen manure (HO) were set up for organic manure substitution application treatments. The results showed that compared with CK, the number of tuber per plant, medium tuber rate and small tuber rate did not change significantly under RN treatment, however, the large tuber rate was decreased by 0.32 percent points and the yield were decreased by 10.93%. The number of tuber per plant were increased by 11.77%, the large tuber rate and medium tuber rate were increased by 0.43 and 6.47 percent points under HO treatment, respectively, and the yield was increased by 19.01%. The potato root under HO treatment had longer root length, larger projected root area, root volume, more tips and forks during the tuber initiation stage, and more tips during the tuber bulking stage compared with CK. The yield was significantly (P<0.01) positively related to the root length during the seedling, tuber bulking and starch formation stage, and the root surface area, the root volume, the number of tips and the number of forks during the tuber bulking stage. Therefore, 90 kg·hm-2 organic nitrogen and 81 kg·hm-2 chemical nitrogen as base fertilizers, and 54 kg·hm-2 chemical nitrogen as topdressing in the tuber formation stage could improve the root growth effectively, promote the formation of effective tuber during the early growth stage, increase the number of tuber per plant and the expansion of tubers, and thus produce a higher yield of potato.

Key words: potato, reduced nitrogen, organic manure substitution, root characteristics, yield

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