The irrigation and fertilization regime of different varieties of Grevillea in Israel are based on existing knowledge for growing various varieties of the Proteaceae family for production of cut flowering branches. However, growers face problems in cultivating Grevillea “Spiderman,” such as leaf chlorosis, prolonged growth until flowering, and reduced quality of cut flowering branches. The present study aimed to examine whether these problems stem from deficiency or excess of Fe, Mn, Zn, P, and Mg, focusing on the effect of these nutrients on growth, flowering, and appearance of visual leaf symptoms and on yield, quality, and vase life longevity of cut flowering branches. The nutrient treatments significantly affected plant development and flowering. Increasing the Fe concentration from 1 to 2 or 3 mg l–1 resulted in improved leaf color, from slightly yellow to dark green. The combination of 2 mg l–1 Fe + 1.8 mg l–1 Mn resulted in early flowering, highest yield, and development of long lateral branches. Low levels of P caused in the first year of treatment leaf chlorosis, which was intensified during the third year, resulting in severe yellowing of the flowering branches. Leaf necrosis and tip burn appeared in treatments with high concentrations of Zn, Mn, and Mg. Deficiency of Fe and Mn and high concentration of P and Mg led to the development of a large number of branches without flowers. The optimal fertilization treatment that yielded the highest quality of flowering branches after harvest was 2 mg l–1 Fe. Branches of this treatment had green foliage at harvest and the longest vase life (10 days) following the recommended postharvest treatment and air transport simulation. Based on the findings of the present research, it can be concluded that the problems in the cultivation of G. “Spiderman,” such as leaf chlorosis, delayed flowering, and reduced quality of flowering branches, result from improper fertilization.
Sci. Plant Anal. 1979 10 83 88
Price C.A. Clark H.E. Funkouser H.E. Functions of micronutrients in plants Micronutrients in agriculture. Soil Sci. Soc. of America, Madison, Wisconson Mortvedt J.J. Giordano P.M. Lindsay W.L. 1972 731 742
Rebeille F. Bligny B. Donee R. Is the cytosolic Pi
information on nutrition and healthier food options may be pivotal in preventing obesity. Supportive environments and communities are fundamental in shaping people’s choices and the aggressive and direct marketing of energy-dense, micronutrient-poor foods is definitely not helpful. Even though there is some
). Micronutrients that are especially targeted for bio-fortification in various crops include vitamin A, iron and zinc. Recently, biofortified cassava cultivars with significantly raised levels of pro-vitamin A carotenoids (pVACs) and low hydrogen cyanide content have been developed by conventional plant breeding
Batch cultures of cyanobacteiium Anacystis nidulans were analyzed continuously for changes in growth and cell composition in relation to boron supply. The lack of boron in the medium had no effect on the growth of this cyanobacterium and on the contents of the organic fractions: chlorophyll, protein and nucleic acids. In addition the growth of Anacystis nidulans in a boron-free medium was neither stimulated nor inhibited by the addition of boron in amounts up to 1.0 mg · 1−1. The uptake of nitrate was similarly unaffected. In view of these results, it is concluded that boron is a non-essential micronutrient for Anacystis nidulans.
Proper disposal and recycling of different industrial waste materials have long been recognized as a prime environmental concern. The present study evaluated the effects of soil amendment of fly ash, a major industrial waste material, on soil properties, plant growth, productivity and metabolites production of safflower (Carthamus tinctorius L.). The soil was amended with varied concentrations of fly ash (0%, 5%, 10%, 25%, 50%, 75% per pot) prior to sowing under field conditions in the herbal garden of Jamia Hamdard. Sampling was conducted at different growth stages, i.e. pre-flowering, flowering and post-flowering. Our results demonstrate that fly ash concentrations up to 25% improved the physicochemical properties of the soil as compared to non-treated control resulting in increased availability to the plant of macro and micronutrients and thereby stimulating plant growth and productivity. Contents of photosynthetic pigments, sugars, protein, and nitrate reductase (NR) activity increased under 25% fly ash amendment. The highest beneficial effect was found during the flowering stage > pre-flowering > post-flowering stages. Further increase in fly ash concentration reduced the stimulated effects on the plants, exhibiting a minimum under 75% fly ash application. Thus, it was concluded that incorporation of 25% fly ash to the cultivation soil not only improves the physicochemical properties of the soil, but also contributes to better growth, yield and metabolism of safflower.
Chloride is an essential micronutrient as a cofactor in the oxidation of water in photosynthesis and as an activator of enzymes. It is readily taken up by plants. Chloride also serves in the plant as a charge balance during cation transport, and contributes to cell hydration and turgor maintenance. In the soil, chloride balances the positive charge of the soluble cations Na, Ca, Mg, and potassium. Treated effluent water, which is increasingly used for agricultural irrigation, contains higher chloride levels then the potable water from which it is derived. High concentrations of chloride in the irrigation water or the soil are toxic to plants and may affect plant function and reduce productivity. Despite the voluminous literature on saline soils, it is difficult to answer the question: how long can water containing high chloride levels safely be used for agricultural purposes under given conditions before damage to soil and plants is observed. The answer to this question must take into consideration soil clay content and clay type, irrigation methods, evaporation conditions, and plant type and composition. The chloride anion is very stable and will not leave the soil system unless it is leached by an excess of good quality irrigation water, or removed from the soil by exported vegetative plant parts. Continuous long-term utilization of recycled water for irrigation may therefore increase the chloride content of the soil, and without proper leaching it will deteriorate soil fertility, and under extreme conditions may render the soil unproductive.
Eucalyptus silver dollar (Eucalyptus cinerea) is cultivated under intensive agronomic practices for production of cut foliage branches for the floriculture industry. A range of damage symptoms, suspected to be related to unoptimized mineral nutrition, routinely occur in the leaves at the production plantations and reduce yield quality. No information is available about the nutritional requirements of Eucalyptus silver dollar, or of any other Eucalyptus species under intense cultivation for cut foliage branches production. In this study we evaluated the hypotheses that: (1) leaf damage symptoms in the Eucalyptus silver dollar plantations might be related to the nutritional status of the leaves; and (2) they are affected by environmental and growing conditions, and will therefore differ between seasons and location of the plantations. To test these hypotheses we studied the seasonal and location variations in the ionomics of damaged and healthy leaves, physiological parameters, and postharvest attributes of cut foliage branches during vase life in four plantations of Eucalyptus silver dollar in Israel. The observed leaf symptoms were also characterized anatomically. The range of concentrations for individual macronutrients in the leaves was (in g kg–1): N (18–40); P (1.2–3.0); K (5.5–17.0); Ca (3.5–14.0); Mg (1.1–2.8); S (1.3–2.6). The concentrations range for micronutrients was (in mg kg–1): B (10–100); Fe (30–170); Zn (14–27); Mn (38–190); Cu (3.5–5.9). None of the identified leaf symptoms correlated with a consistent increase or decrease of the content of a specific mineral nutrient or heavy metal compared to the healthy leaves, suggesting that they were not caused by mineral deficiency or toxicity. The leaf ionomics was affected by season and varied between locations. The main damage symptoms observed in the four examined plantations during the four harvests were red and purple spots, and oil stains. Postharvest experiments showed that the quality of branches was reduced during 7–15 days of vase life following transport simulation to the local market. The degree of reduced quality during vase life was also dependent on the location of the plantation and the season of harvest. The oil stains appeared in the two most southern locations during summer, suggesting that this symptom might be derived from the summer conditions such as the high temperatures and high light intensities occurring in the southern part of Israel.
., Brown, P.H. 1997. Absorption of boron by plant roots. Plant and Soil 193: 49-58.
Krauskopf, K.B. 1972. Geochemistry of micronutrients. In: Mortvedt, J., Giordano, M., Lindsay W.L., eds. Micronu-trients in agriculture. Soil Science Society of America, Madison, Wisconsin, pp. 7-36.
Nambiar E.K.S. The effects of water content of the topsoil on micronutrient availability and uptake in a siliceous sandy soil. Plant Soil 1977 46 175 183
Richards J.H. Caldwell M.M. Hydraulic lift: Substantial nocturnal water transport between soil layers by Artemisia tridentata roots. Oecologia 1987