Effects of different fertilization practices on the growth, yield and dry matter content of carrot

Abstract

Abstract. The effects of different fertilization practices on the carrot root and shoot dry weights, yield, dry matter contents and root/shoot ratio were studied in field experiments. Unirrigated and irrigated placement and broadcast fertilization, fertirrigations without basic fertilization, fertirrigations with basic fertilization, and PK placement with N fertirrigations were compared. In addition, split application was compared to single application of nutrients. The soil nutrient levels were studied by soil analysis. The carrot root and shoot samples were collected three times during the growing period. Cv. Nantes Duke Notabene 370 was grown.The carrot shoots reached their maximum weight already by three months, whereas roots grew slowly during the first two months but grew considerably during both the third and fourth month. The root and shoot dry weights were positively correlated at all sampling dates in both years (r a o.77***), The big photosynthetizing apparatus caused the production of high root yield. The placement fertilization of granular NPK fertilizer increased the yield as compared to broadcast of granular NPK fertilizer (p = 0.009**). The yield was also increased by the placement of P and K as compared to treatments without placement fertilization of P and K (p = 0.03*). There was no difference in yields between single application and split application. Irrigation decreased the yield in 1985 (p = 0.03*). In 1986 the yield was significantly higher than in 1985 (p = 0.000***).At harvest the fertilization did not affect the dry matter content of carrot roots when compared with unfertilized treatments. The difference in dry matter content was greater between years (p = 0.000***) than between fertilization practices (p = 0.05*). The treatment PK placement with N fertirrigations yielded carrots with a higher dry matter content than did the NPK fertirrigation treatments. Besides the fertilization experiment samples from two organically cultivated fields were collected to obtain data concerning organicallycultivated carrots and soils.

Effects of different fertilization practices on the N03-N, N, P, K, Ca, Mg, ash and dietary fibre contents of carrot

“…1), a result probably caused by weather conditions. In August, September and October the mean day temperature and the number of sunshine hours were higher in 1985 than in 1986 (Evers 1988). This is in agreement with the literature.…”

“…Organically cultivated carrot roots had a higher P content than those of the fertilizer experiment ( Table 2). The P concentration in organically cultivated soils was remarkably higher than in the fertilization experiment (Evers 1988). In the literature, the P content of carrot leaves has been reported to be 0.19-0.27 % DM on mineral soils (Bishop et al 1973) and 0.17-0.21°7o DM (Nilsson 1979). In the study of Nilsson (1979), organic fertilizer in-creased the P content of leaves as compared to mineral fertilizer.…”

“…Carrot cv. Nantes Duke Notabene 370 Sv was grown as reported elsewhere (Evers 1988 (1985). Total N was determined according to the Kjeldahl method (Anon.…”

“…At location 1, the N-amount of the compost fertilization was 113 kg/ha watersoluble N and 450 kg/ha total N. At location 2, the N amount of the compost fertilization was 47 kg/ha water-soluble N and 424 kg/ha total N (Evers 1988). The NQ 3 -N values are higher than those reported by Nilsson (1979).…”

The myth of organic agriculture

“…Also, Eghball et al (1997) found 20% to 40% loss of total N and 46% to 62% loss of total C during composting of beef cattle feedlot manure, as well as significant losses of K and Na (> 6.5% of total K and Na) in runoff from composting winrows during rainfall. Consequently, minerals from manure breakdown have not been observed to produce crops with superior qualities as organic farmers assert (Hansen 1980;Evers 1988;Conklin & Thompson 1993). Contrary to this, insufficient supply of these nutrients will lead to malnutrition of the crops, resulting in low yields and poor quality of the produce.…”