Organic fertilization leads to increased peach root production and lifespan

Abstract

We evaluated the effects of mineral and organic fertilizers on peach root dynamics in the growing season from 2003 to 2006 in a nectarine (Prunus persica L.) orchard, planted in 2001 and located in the Po valley, northeastern Italy. Very few studies have conducted long-term investigations of root dynamics of fruit crops. Our main objective was to determine whether organic fertilizers affect root dynamics differently than mineral fertilizers. The experiment was a completely randomized block design with four replicates of three treatments: unfertilized, mineral fertilized and composted with municipal waste. Mineral fertilizers included P (100 kg ha(-1) year(-1)) and K (200 kg ha(-1) year(-1)) applied only at planting and N (70-130 kg ha(-1) year(-1)) split into two applications, one at 40 days after full bloom (60%) and the other in September (40%) each year. The compost fertilization represented a yearly rate of 10 metric tons (t) dry weight ha(-1), which approximates (in kg ha(-1) year(-1)) 240 N, 100 P and 200 K, split similarly to that described for the mineral fertilization of N. Both root growth and survival were evaluated at 20-day intervals during the growing season by the minirhizotron technique. Compost increased the production of new roots compared with the other treatments (P < 0.01). Roots were mainly produced at a depth of 41-80 cm and from March to May and in late summer. An analysis of covariance indicated no significant effect of soil nitrate on root production (P = 0.47). The root lifespan was longer in compost-treated trees than in mineral-fertilized or unfertilized trees (P < 0.01) and it was strongly affected by time of birth; roots born later in the summer lived longer than those born in the spring. Across years and treatments, the average root lifespan was positively correlated with soil nitrate (r = 0.60; P < 0.001). Variation in root lifespan with method of fertilization could be accounted for by variation in soil nitrate concentration as indicated by no effect of fertilizer treatment on root lifespan when soil nitrate was included as a covariate. These results reveal how shifting from mineral to organic fertilizers may shift both soil properties and nutrient availability, leading to changes in both root production and lifespan.

Integrated Soil Fertility Management: Impact of &lt;i&gt;Mucuna&lt;/i&gt; and &lt;i&gt;Tithonia&lt;/i&gt; Biomass on Tomato (&lt;i&gt;Lycopersicon esculentum&lt;/i&gt; L.) Performance in Smallholder Farming Systems

“…This is consistent with greater root production and lifespan induced by compost and mulching as compared to mineral fertilizer [40]. In addition, mineral fertilizer induces high nitrate ( 3 NO − ) pulses, which could easily be leached as a result of its high mobility in the soil, coupled with the heavy rainfall condition of the study area.…”

<b>Nutritional status, yield and composition of peach fruit subjected to the application of organic compost

“…Consequently, the yield per plant and per hectare in 2008 and 2009 increased quadratically (Table 4). This result potentially occurred because the added compost was mineralized by microorganisms and the nutrients within the compost were released (Baldi, Toselli, Eissenstat, & Marangoni, 2010b;Ramos et al, 2011), which would increase the TOC content, mineral N, available P, and the exchangeable K, Ca, and Mg contents in the soil quadratically (unpublished data) as the addition of compost increased at 72 L compost per plant -1 . Some studies showed that the application of organic compost in the soil improved the soil physical attributes by increasing the soil porosity and reducing the soil density (Erhart, Feichtinger, & Hartl, 2007;Melo et al, 2012).…”

Impact of biochar amendment on the growth, physiology and fruit of a young commercial apple orchard

“…C treatment compared to the control treatment observed in the first year may suggest otherwise. Nonetheless, the effect of compost on growth and crop yield in fruit trees has been shown to vary from neutral to positive effects, depending on the nature, and rate of compost application (Baldi et al 2010;van Schoor et al 2012). The positive effect of biochar treatment on growth responses was not evident until year 3 suggesting that the full effects of biochar treatment on perennial fruit tree responses may not be realised by short timescale studies.…”