Effects on table beet of pre-plant organic and Na-amended inorganic fertilizers

Abstract

Table beet ( Beta vulgaris L.) seed was planted into field plots treated with either (1) a pre-plant inorganic fertilizer amended with several rates of sodium (Na), (2) a pre-plant application of fish bone meal from a salt fish processing plant or (3) a pre-plant application of liquid fish silage from a fresh fish processing plant. The fish bone meal and liquid fish silage did not receive supplemental Na. The Na-amended fertilizer treatments were first applied to a loamy sand (2–3% organic matter) soil type, and beet root total yields and flavour were not significantly affected by Na additions up to 196 kg ha −1 (500 kg NaCl ha −1) with soil Na ranging from 180 to 270 kg ha −1. In a second season in which Na-amended fertilizer treatments were compared with fish bone meal and liquid fish silage, there were no significant differences in the flavour of beet roots grown in a sandy loam (4–6% organic matter) soil type. Beet leaf and root Na increased, calcium (Ca) and magnesium (Mg) decreased as Na level increased in the pre-plant fertilizer. Leaf potassium (K) decreased with increasing Na in the applied fertilizer. Beet leaf and root Na and soil Ca, Na and phosphorus (P) were higher, and leaf P, K and Ca were lower from plots treated with fish bone meal compared with liquid fish silage. Yield was not affected by Na additions up to 392 kg ha −1 (1000 kg NaCl ha −1) in the pre-plant fertilizer with soil Na ranging from 130 to 140 kg ha −1. Total yield and mean beet root weight across all grades were significantly higher, and the percentage by weight of roots in the small cull size (< 3.8 cm) was significantly lower from plants receiving fish bone meal compared with those receiving liquid fish silage. Results indicate no yield advantage by including Na in the pre-plant fertilizer. These two fish waste products appear to be suitable alternatives to a commercial fertilizer on this sandy loam soil type. The 7–8% Na content of the fish bone meal did not affect beet root yield or flavour when compared with the no Na fertilizer treatment.