Effects of Nitrogen and Phosphorus Fertilization on Photosynthetic Properties of Leaves and Agronomic Characters of Alfalfa over Three Consecutive Years

Jiantao Zhao, Rongzheng Huang, Kaixin Yang, Chunhui Ma and Qianbing Zhang ()
Additional contact information
Jiantao Zhao: College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
Rongzheng Huang: College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
Kaixin Yang: College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
Chunhui Ma: College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
Qianbing Zhang: College of Animal Science and Technology, Shihezi University, Shihezi 832003, China

Agriculture, 2022, vol. 12, issue 8, 1-15

Abstract: The present study aimed to investigate the nitrogen (N) and phosphorus (P) fertilization of continuous addition effects plant biomass, the physiological properties of leaves and the antioxi-dant enzyme activities of alfalfa ( Medicago sativa L) in the northern Xinjiang region; including the no fertilization (CK), nitrogen fertilization (N, 120 kg·ha −1 ), phosphorus fertilization (with low amount of N) (P, 100 kg·ha −1 P and 23.5 kg·ha −1 N) and combined nitrogen and phosphorus fertilization (NP, 120 kg·ha −1 N and 100 kg·ha −1 P) on the K well supplied soil. After three consecutive years of the supply of N and P fertilization, samples were taken at the first flowering of alfalfa (four clippings in the total year) to determine its pigment concentration, stomatal aperture, antioxidant enzyme activity and hay yield. The results showed that NP fertilization promoted growth with a higher number of branches and hay yield of alfalfa, while N or P fertilization alone had a positive effect on the growth of alfalfa. However, P fertilization significantly increased the carotenoid (Car) content at the early flowering stage of alfalfa leaves (during four clippings) ( p < 0.05), In addition, NP ferti-lization enhanced stomatal aperture, increased the antioxidant enzyme activity and decreased the oxidized substance at the early flowering stage of alfalfa leaves. The results showed that a N and P balance rather than an absolute amount of either enhanced the growth of alfalfa, and N or P fertili-zation affects physiological traits differently. We propose that NP fertilization increases the nutri-tional characteristics and physiological characteristics, enhancing the adaptive capacity of alfalfa and making it better adapted to external environmental changes.

Keywords: alfalfa; fertilization; photosynthetic pigment; stomatal aperture; antioxidant enzyme activity (search for similar items in EconPapers)
JEL-codes: Q1 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 (search for similar items in EconPapers)
Date: 2022
References: View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.mdpi.com/2077-0472/12/8/1187/pdf (application/pdf)
https://www.mdpi.com/2077-0472/12/8/1187/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jagris:v:12:y:2022:i:8:p:1187-:d:884072

Access Statistics for this article

Agriculture is currently edited by Ms. Leda Xuan

More articles in Agriculture from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().