Nitrogen Fertigation Concentration and Timing of Application Affect Nitrogen Nutrition, Yield, Firmness, and Color of Apples Grown at High Density

Abstract

<jats:p>A randomized complete block, split-plot experiment with six replicates was established and maintained for the first six fruiting seasons (1999 to 2004) in a high-density apple [<jats:italic>Malus sylvestris</jats:italic> (L.) Mill var. <jats:italic>domestica</jats:italic> (Borkh.) Mansf.] orchard on M.9 rootstock planted in Apr. 1998. This report assesses responses to six main-plot fertigation treatments, each containing three tree subplots of five different cultivars (Ambrosia, Cameo, Fuji, Gala, and Silken). Fertigation treatments were a factorial combination of two nitrogen (N) rates and three N application timings. N was applied at low (28 mg N/L) or high (168 mg N/L) concentrations daily at 0 to 4, 4 to 8, or 8 to 12 weeks after full bloom (wafb). Under greater N inputs, all cultivars had increased midsummer leaf and harvested fruit N concentrations, decreased fruit firmness, and in heavy crop years, decreased percent red color. Annual yield of all cultivars was significantly increased by N rate in a single year, but their cumulative yields were not different between treatments as a result of rate or timing. Altering the timing of N application within 12 wafb only affected leaf and fruit tissue N concentration. Leaf N was higher after 4 weeks of fertigation any time, although concentrations declined over the growing season, reaching minimum values around harvest. Fruit N was increased by fertigation 4 to 12 wafb. Yield, fruit firmness, and color were unaffected by fertigation timing. Critical fruit quality issues for ‘Gala’ and ‘Silken’ were small fruit size, for Ambrosia low fruit numbers, and for ‘Cameo’ soft fruit. ‘Fuji’, which achieved high yield and leaf N concentration and firm fruit, had poor red color regardless of N treatments.</jats:p>

Minimal nitrogen and water use in horticulture: Effects on quality and content of selected nutrients

“…Several studies have consistently reported the negative effects high N applications had on reducing red color or increasing the green background of apples (Marcelle, 1995;Neilsen et al, 2009;Tahir, Johansson, & Olsson, 2008) due to a decrease in both chlorophyll degradation and anthocyanin synthesis in the skin (Wang & Cheng, 2009). High N also reduced storage performance in apple (Fallahi, Fallahi, & Seyedbagheri, 2006) and kiwi fruits (Vizzotto, Lain, & Costa, 1999).…”

“…Leaching of N and phosphorous (P) due to excessive applications in agriculture are widely considered the main cause of eutrophication in fresh and salt water supplies throughout the world (Burt et al, 2009b;Erhart, Feichtinger, & Hart, 2007). Several practices have recently been implemented to try to reduce ground water pollution by N, such as split applications (Drake, Raese, & Smith, 2002), target timing (Tagliavini & Marangoni, 2002;Wade, Holzapfel, Degaris, Williams, & Keller, 2004), integrated production (Ganeshamurthy et al, 2004;Peck et al, 2006), fertigation (Neilsen, Neilsen, & Herbert, 2009;Raina, Thakur, Shashi, & Spehia, 2005), best management practices (Alva, Paramasivam, Fares, Obreza, & Schumann, 2006;, foliar applications (Dong, Neilsen, Neilsen, & Fuchigami, 2005;Reay, Fletcher, & Thomas 1998), and varying the type of N sources (El-Boray, Mostafa, Iraqi, & Mohamed, 2006;Erhart et al, 2007;Racskó et al, 2008;Rosen & Allan, 2007). While not all of the above mentioned practices reduced the total amount of N applied; all were effective in limiting pollution by increasing plant N use efficiency.…”

“…High N also reduced storage performance in apple (Fallahi, Fallahi, & Seyedbagheri, 2006) and kiwi fruits (Vizzotto, Lain, & Costa, 1999). Susceptibility to a range of physiological disorders increased with high N fruit content, such as apple watercore (Fallahi, Fallahi, Retamales, Valdés, & Tabatabaei, 2006;Marcelle, 1995); apple fruit softening (Marcelle, 1995;Neilsen et al, 2009;Sams, 1999); melon fruit softening (Cabello, Castellanos, Romojaro, Martínez-Madrid, & Ribas, 2009) and decreased apple acidity (Raese, Drake, & Curry, 2007). In addition, high N increased susceptibility to cactus pear fungal diseases (Ochoa, Leguizamón, & Uhart, 2006), and reduced pear tree cold tolerance (Raese, 1997) while Quaggio, Mattos, Cantarella, Almeida, and Cardoso (2002) reported a decrease in essential oil content of lemon fruits.…”

Efficient Irrigation for Optimum Fruit Quality and Yield in Apples

“…Methods of irrigation affect water consumption, which is a critical issue in many parts of the world including the Pacific Northwest region of the United States. Irrigation methods and injection of nutrients, particularly nitrogen, through water (fertigation) also play major roles in apple fruit quality and production (Fallahi et al, 2001a;Neilsen et al, 2009).…”

The Effect of Deficit Irrigation and Crop Load on Leaf and Fruit Nutrition of Fertigated ‘Ambrosia’/‘M.9’ Apple

“…N was fertigated daily as calcium nitrate (15.5N-0P-0K) for 6 weeks after bloom to provide 75 g N/tree. Subsequent research indicated that the N application rates were in excess of requirements for high-density apple, which can be as low as 25 g N/tree (Neilsen et al, 2009). P was fertigated for 1 d immediately after full bloom and before the start of regular N applications as ammonium polyphosphate (10N-15P-0K), which supplied 20 g P/tree and 13.3 g N/tree.…”