Controlled-release sources of N and K were compared with soluble sources on young `Valencia' orange trees (Citrus sinensis [L.] Osb.). The effects of these fertilizers on leaf mineral concentration, soil chemical analysis, and tree growth were evaluated for 3 years. Soluble fertilizers were generally more readily available but had shorter residual effects on leaves and soil than controlled-release fertilizers. In the top 30 cm of soil, the plots treated with controlled-release N had 23% more total N than those treated with soluble N sources, while the plots fertilized with controlled-release K contained 56% more extractable K than those that received soluble K. Different effects on leaf and soil N between the two controlled-release N sources, sulfur-coated urea (SCU) and methylene urea (MU), were also found. With the use of controlled-release fertilizers, application frequency was reduced from a total of 15 to six applications with no adverse effects on tree growth, leaf mineral composition, or soil fertility during the first 3 years. Combining soluble and controlled-release fertilizers in a plant nutrition program offers an economical and effective strategy for citrus growers.
Mongi Zekri and Robert C.J. Koo
Alireza Talaie*, Alireza Esmaili Falak and Mohammad Ali Asgari
The main aim of this study was to investigate the effects of two apple rootstocks (M9 and Seedling) on the growth, total yield, fruit quality and mineral composition in leaves and fruits of two Iranian cultivars Golab Kohanz and Shafiabadi. The 10-year-old experimented trees were on stage of commercial cropping. The experiment was conducted in a randomized complete-block design in split plot tests with two factors and four replications.The effects of rootstocks on trunk diameter, current seasonal shoot length, primary fruit set percentage, total yield/ha and individual fruit weight were significant (P < 0.01) in first year, but not significant on total yield and individual fruit weight in the second year. The effect of cultivar was only significant at current seasonal shoot length in the first year and total yield and individual fruit weight in both years. Fruit characters were also affected by rootstock, so fruit on M9 rootstock had more flesh firmness, most PH, TSS, and dry matter, but the effect of cultivars was not significant on fruit quality characters in both years. Cultivar Shafiabadi on M9 rootstock produced the highest yield/ha in all treatment combinations. The results of mineral analysis relieved the effects of rootstock on N and Zn concentration in leaves. Golab Kohanz/M9 rootstock showed the highest K content in leaves while the highest Zn amount was Golab Kohanz/Seedling rootstock. Other nutrient contents were affected neither by rootstocks nor cultivars. In fruit, rootstock effect on Mg and P concentration was significant; and the highest K content was found in fruit of Golab Kohanz/M9 and the highest Mg and Ca amount was also recorded in Golab Kohamz/Seedling rootstock.
Catherine M. Grieve, Christy T. Carter* and James A. Poss
Saline wastewaters may provide a valuable water source for the irrigation of selected floriculture crops as demand for quality water increases. A completely randomized design with 3 replications was used to test the effects of salinity on productivity and mineral accumulation on each of two Limonium species grown in greenhouse sand tanks. Three-week-old seedlings (n = 15) of Limonium perezii `Blue Seas' and L. sinuatum `American Beauty' were exposed to 7 salinity treatments (2.5 (control), 7, 11, 15, 20, 25, and 30 dS·m-1) prepared to simulate saline drainage waters of the San Joaquin Valley (SJV) in California. After 10 weeks, vegetative material from five plants from each tank was harvested to assess mineral composition (total-S, total-P, Ca2+, Mg2+, Na+, K+, and Cl-), for each variety. Ion selectivity coefficients were calculated by dividing the ratio of specific ions in the plant by those found in the medium. Stem length and weight, and flower stem numbers were determined at harvest. Salt tolerance thresholds based on stem length for L. perezii and L. sinuatum were 2.5 and 7.0 dS·m-1, respectively. Maximum growth of both species declined as salinity increased, but both species were able to complete their life cycles at 30 dS m-1. L. sinuatum had higher leaf concentrations of Na+, K+, Mg2+, Cl-, and total-P than L. perezii. K+ was preferentially accumulated with regard to Na+ by both species, but was significantly higher in L. sinuatum. Limonium perezii and L. sinuatum can be rated as sensitive and moderately salt tolerant plants, respectively.
Bhaskar R. Bondada
Drift hazards and the effects of 2,4-dichlorophenoxy acetic acid (2,4-D) spray drift on woody perennials have been commonly observed since its discovery in the 1940s; however, 2,4-D-induced phytotoxicity, morphogenesis, and structural and compositional anomalies of their vegetative and reproductive structures are not well understood. Healthy and 2,4-D-injured shoots of grapevine (Vitis vinifera L.) from a commercial vineyard experiencing persistent drift were compared. The morphoanatomy of healthy and 2,4-D-injured leaves and berries were examined using light and scanning electron microscopy (SEM). Along with the microscopic examinations, stomatal conductance (g S), leaf growth characteristics, and mineral composition were also determined. The morphoanatomy of healthy leaves resembled that of a typical angiospermic leaf. By contrast, shoots exposed to 2,4-D phytotoxicity displayed epinastic behavior and developed grotesquely malformed leaves that were thick, fan-shaped, enated, and interveinally puckered as a result of fasciation of veins. The cellular architecture, including the vascular bundles, was altered as a result of the formation of parenchymatous replacement tissues. The g S, leaf index, leaf area, and petiole dimensions were significantly reduced in the 2,4-D-injured leaves. 2,4-D-injured leaves; however, accumulated high levels of nitrogen, potassium, and iron compared with healthy leaves. The clusters (fertilized inflorescences) of the injured shoots developed epinastic curvature and predominantly bore live green ovaries (seedless unripened pseudofruit) instead of true berries (fertilized fully ripened fleshy fruit). These abnormalities are expected to severely perturb the vital functions of photosynthesis and transpiration as evidenced by low g S and poor fruit set leading to senescence and localized necrosis ultimately causing death of current-season shoots.
the objectives are to: (1) Investigate changes in physicochemical constituents and mineral composition of cocoa pulp during fermentation; (2) Investigate changes in physicochemical constituents and flavor precursors of cocoa bean pulp during
Ida Di Mola, Youssef Rouphael, Giuseppe Colla, Massimo Fagnano, Roberta Paradiso and Mauro Mori
, G.L. Witter, M.H. Godori, R.S. Barros, G.T. Bortolotto, O.G. 2005 Growth and yield of lettuce plants under salinity Hort. Bras. 23 931 934 Borgognone, D. Rouphael, Y. Cardarelli, M. Lucini, L. Colla, G. 2016 Changes in biomass, mineral composition
Philip J. White, John E. Bradshaw, M. Finlay, B. Dale, Gavin Ramsay, John P. Hammond and Martin R. Broadley
improve yields on infertile soils ( White and Broadley, 2005a ). MINERAL COMPOSITION OF POTATOES Potatoes are an excellent source of carbohydrates, vitamins, and minerals. A single medium-sized potato weighing 200 g fresh weight (FW) can provide ≈26% of
Menahem Edelstein, Roni Cohen, Meital Elkabetz, Shimon Pivonia, Ami Maduel, Tom Sadeh-Yarok and M. Ben-Hur
, rootstocks with higher efficiency of Mn, Zn, and Mg uptake should be sought. Literature Cited Borgognone, D. Colla, G. Rouphael, Y. Cardarelli, M. Rea, E. Schwarz, D. 2013 Effect of nitrogen form and nutrient solution pH on growth and mineral composition of
Alfonso José Lag-Brotons, José Martín Soriano-Disla, Ignacio Gómez and José Navarro-Pedreño
growth reduction, no visual symptoms of nutritional deficiencies were observed. Table 4. Cardoon morphological parameters at the end of the experiment (mean values ± sd , n = 3). The mineral composition of cynara tissues and the effects of saline
Cristian Silvestri, Gianmarco Sabbatini, Federico Marangelli, Eddo Rugini and Valerio Cristofori
involved in hyperhydricity has been observed ( Liu et al., 2017 ). Four weeks of growth in MS, DKW, QL, and WPM showed the significant influence of media mineral composition ( Fig. 2 ) on the studied parameters ( Table 2 ). On MS and DKW media, maximum