Influence of Nitrogen and Phosphorus Fertilization on Quality and Germination Potential of Smooth Bromegrass Seed

Abstract

A field experiment was conducted to evaluate the effects of two nitrogen levels (N: 0,100 kg ha-1) and four phosphorus levels (P: 0, 60, 90, 120 kg P2O5 ha-1) on smooth bromegrass (Bromus inermis Leyss.) seed quality by measuring germination, mean germination time (MGT), protein and phosphorus contents, acid phosphoesterase (APT) and antioxidant enzymes activities, hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents and electrical conductivity. Nitrogen application improved seed protein content and reduced P content at different P application levels, while there was a contradicted effect for P application on increasing seed P content and decreasing protein content. Mean germination time of seeds harvested from 100 kg N ha-1 treatment was significantly (P<0.05) prolonged, indicating that N application could delay seed germination rate. Phosphorus deficiency or excessive P application level would also delay the initiation of germination. Seed-aging assays showed that N application could decrease relative loss of germination (RLG) through improving CAT and APT activities and reducing the content of H2O2 and MDA at the lower P application. From the findings of the present study, optimum application ratio of N and P improved germinability and longevity of smooth bromegrass seed.

Direct effects of nitrogen addition on seed germination of eight semi‐arid grassland species

“…The sensitivity of different species germination to nitrogen addition is various (Davis, 2007). Previous studies found that the N application could delay the seed germination rate of Bromus inermis (Zhu, Wang, Yan, Mao, & Mao, 2018). Therefore, the seed germination responses to N treatments were species-specific, mainly positive or unimodal (Ochoa-Hueso & Manrique, 2010).…”

Geographical patterns and environmental influencing factors of variations in Asterothamnus centraliasiaticus seed traits on Qinghai-Tibetan plateau

“…These nutrient variations further influence seed morphological traits, represented by seed mass (Wu et al, 2018). Zhang et al (2016) concluded that differences in the content of AN in the soil significantly affected the composition of amino acids in the seed (Mon et al, 2016), further promoting the overall content of soluble proteins (CSP) in the seed (Zhu et al, 2018). Additionally, high levels of nitrogen lead to a decrease in the content of crude fat (CCF) in the seed and an opposite trend in CSP and CCF (Urbaniak et al, 2008;Solis et al, 2013).…”