Emerald Harvest Micro
Give your crops what they need when they need it most, with Emerald harvest Micro. The nutrient formula supplies plants with precise nutrient formulations that deliver the right amounts of Nitrogen, Phosphorous, and Potassium throughout the crop life cycles.In addition to regulating the amounts of N, P, and K so that your high-yield plants flourish Micro provides a delicious mix of trace elements as well as many chelated micronutrients.
Calcium Nitrate, Ammonium Nitrate, Potassium Nitrate, Urea, Cobalt Nitrate, Iron EDTA, Sodium Borate. Sodium Molybdate, Copper EDTA, Manganese EDTA, and Zinc EDTA
Calcium is an integral part of plant cell wall and gives strength to binding and linking molecules together. Calcium participates in metabolic activities within the cells and mediates intracellular communications. In the absence of a balanced source of Calcium, metabolism in plants cell either slows down or stops altogether. Calcium Nitrate is the ideal inorganic N fertilizer source and used when Calcium and Nitrogen are required to be supplied at the same time.
- Retains Magnesium and Phosphorous in plants
- Increases quality of crops
- Calcium deficiency leads to stress
- Improves function of antioxidants.
- Protects plant cell from biochemical stress
- Nitrate is reduced to Ammonium (Nitrogen source) and essential for Ammino acid, protein, DNA, RNA, ATP and hormones
A common Nitrogen source as it contains both Nitrogen and Ammonium. It is less concentrated than urea but is more stable without loss of Nitrogen in the atmosphere.
- Ammonium is said to increases the vegetative growth in plants
- Augment Calcium, Potassium and Phosphorous uptake
- Effects the chemical composition of the whole plant
- Influence enzyme activity
An exclusive source of Potassium and Nitrogen for optimal plant nutrition. The salt is absorbed efficiently and is free of chloride. The optimum level of potassium improves quality and overall yield, and Nitrates enhances formation of organic acid.
- Mediates opening of flowers
- Increased leaf area duration
- An optimum level leads to increase in the concentration of sugar, glutamic acid, aspartic acid and alanine.
- Improves the taste and aroma of fruits.
- Resistance towards stress
- Increases chlorophyll concentration
- Improves tolerance towards drought and frost
- Plays a crucial role in development of flowers
It is a Nitrogen release fertilizer and has a highest Nitrogen content of most of the nitrogenous fertilizer available in the market.
- An important source of Nitrogen
- Retards aging in plants
- Increases tolerance to freezing
Cobalt is an essential component of quite a few enzymes and co-enzymes. It forms complexes on interaction with other elements.
- Essential for plant growth
- Enhances stem elongation
- Increases plant height
- Increases number of branches and leaves
- Retardation of senescence of leaves
Micronutrients are essential in all stages of plant development. However, they are not absorbed directly and are transported in a chelated form. EDTA is a chelating agent, and Chelation is a process wherein the nutrient moiety is bound to an organic molecule like amino acid or proteins so that it is quickly absorbed by plants and last longer in the medium. EDTA enhances budding and flowering and draws excess mineral nutrient out of solution. It also boosts phytoextraction of heavy metals.
- Without Iron plants cannot produce chlorophyll, no oxygen, and no green appearance.
- Mediate enzymatic activity
- Copper is essential for growth during seedling stage and prevents malformed head.
- Imperative in flower bud initiation.
- Vital role in photosynthesis
- Essential for carbohydrate and protein metabolism
- Adds color and flavor
- Acts and co-factor in activating enzymes for biosynthesis of aromatic amino acid.
- Promotes stem elongation
- Mediates apical development
- Prevents stunted leaf growth.
- Improves fruit quality
- Zinc mediates pollen function and fertilization
- Zinc deficiency decreases thickness of leaves
- Zinc deficiency reduces leaf chlorophyll concentrations
- Plants have stunted growth in absence of Zinc
- Boron is essential for plant growth
- Borin deficiency leads to reduced fruit quality
- Boron application improves calcium mobility
- Develops pollen energy
Helps retain phosphorus and Mg in the plant- The effects of temporary calcium deficiency on the growth and mineral nutrition of whole tomato (Lycopersicon esculentum All. cv. Rondello) plants were investigated at the 22–23 leaf stage. Three deficiency period durations (5, 8, and ten days or ‐Ca5, ‐Ca8, and ‐Ca10, respectively) were tested during the two series of hydroponic experiments in a greenhouse. At the end of the calcium deficiency period, the plants were supplied again with a standard nutrient solution. In the plants subjected to a 5‐day calcium deficiency, stem growth, and new leaf formation was slowed 10–12 days after the onset of the treatment. The effect was rapidly attenuated, and no visual symptom was observed after that. The stem growth slowdown induced by treatments ‐Ca8 and ‐Ca10 8–10 days after the onset of calcium deficiency was followed by the rapid appearance of visual symptoms and by the death of the apical meristem. Thus, beyond five days, even though the plant was supplied again with calcium, the appearance of visual symptoms shortly preceded the total necrosis of the apical meristem of the stem. Two major phenomena were characterized by the analysis of plant uptake and contents. The calcium deficiency showed the occurrence of an active calcium‐magnesium antagonism mainly localized in the leaves, which suggests the influence of calcium on magnesium translocation to the above‐ground parts. Besides, in the absence of calcium in the nutrient solution, phosphorus uptake was decreased as shown by the reduced root content. The phenomenon might be related to the occurrence of precipitated dicalcium phosphate at the root surface. The precipitate was likely to constitute a calcium reserve which was rapidly depleted by the plant after a 5‐day deficiency:
- Morarda, A. Pujosa, A. Bernadaca & G. Bertonia, 1996. Effect of temporary calcium deficiency on tomato growth and mineral nutrition. Journal of Plant Nutrition, Volume 19, Issue 1, pages 115-127
Increases crunchiness of lettuce (quality of crop)
While nitrogen (N) form affects growth and yield of many vegetables crops, previous studies suggested that N-form may affect lettuce (Lactuca sativa L.) quality more than growth and yield. The objectives of this research were to evaluate the effect of the N-source used as injection material on the field performance and sensory attributes of three lettuce types. Three lettuce types (Romaine, butterhead and looseleaf) were grown with plasticulture and side dressed with weekly injections of calcium nitrate, potassium nitrate, or ammonium nitrate, each at a rate of 7 kg N ha−1 week−1. All lettuce type reached marketable size 49 days after transplanting. N-source effect on marketable yield and the head number were not significant (P>0.05). After harvest, lettuce samples were prepared for sensory evaluation. Panelist found that crunchiness of calcium nitrate-fed plants (4.8 cm) was significantly (P=0.05) higher than that of plants receiving potassium nitrate (4.4 cm) or ammonium nitrate (4.2 cm). These results suggest that while growers may use ammonium nitrate because of its cost, they should consider using calcium nitrate to enhance lettuce crunchiness:
Eric Simonne, Amy Simonne & Larry Wells, 2001. Nitrogen source affects crunchiness, but not lettuce yield. Journal of Plant Nutrition, Volume 24, Issue 4-5, pages 743-751
Calcium deficiency causes bitter pit in apples
Calcium concentrations in apples were found to be correlated with bitter pit susceptibility, a low calcium level being synonymous with giant pit susceptibility. The standard of calcium in the fruit three weeks before harvest was as reliable a guide for predicting pit as the concentration in the fruit at harvest. However, between districts and varieties, and in different seasons, there were marked differences of calcium above which fruit was unlikely to develop pit. Although calcium concentration was most closely correlated with pit, potassium and, to a less extent, magnesium concentration were also positively associated with the disorder. The ratio of K/Ca was very highly correlated with pit:
R.B.H. Wills, K.J. Scott, P.B. Lyford & P.E. Smale, 1976. Prediction of bitter pit with calcium content of apple fruit. New Zealand Journal of Agricultural Research, Volume 19, Issue 4, pages 513-519.
Calcium deficiency leads to stresses
While growing in the field, plants may encounter several different forms of abiotic stress simultaneously, rather than a single stress. In this study, we investigated the effects of calcium (Ca) deficiency on cadmium (Cd) toxicity in rice seedlings. Calcium deficiency alone decreased the length, fresh and dry weight, and the Ca concentration in shoots and roots. Also, the content of glutathione (GSH), the ratio of GSH/oxidized glutathione, and the activity of catalase were lower in Ca-deficient leaves compared to control leaves. Exogenous Cd caused a decrease in the contents of chlorophyll and protein and induced oxidative stress. Based on these stress indicators, we found that Ca deficiency enhanced Cd toxicity in rice seedlings. Under exogenous Cd application, internal Cd concentrations were higher in Ca-deficient shoots and roots than in the respective controls. Moreover, we observed that Ca deficiency decreased heat-shock (HS) induced expression of HS protein genes Oshsp17.3, Oshsp17.7, and Oshsp18.0 in leaves thereby weakening the protection system and increasing Cd stress. In conclusion, Ca deficiency enhances Cd toxicity, and Ca may be required for HS response in rice seedlings:
Shih-Chueh Cho, Yun-Yang Chao, Ching Huei Kao, 2012. Calcium deficiency increases Cd toxicity and Ca is required for heat-shock induced Cd tolerance in rice seedlings. Journal of Plant Physiology, Volume 169, Issue 9, Pages 892–898.
As the symptoms of calcium deficiency develop in plants, there is often a stage in which the tissues are water-soaked and one involving cell breakdown with the loss of turgor (as in internal analysis of apples). Eventually, the tissue may become desiccated yielding a dry, more or less extensive area of necrosis. Two mechanisms are proposed. There is evidence that calcium deficiency renders membranes permeable which would account for a loss of turgor and permit cell fluids to invade intercellular spaces. An alternative situation may develop in soft, succulent fruits, the cells of which burst under hypotonic conditions in vitro. It is suggested that exogenous water may enter a fruit from the atmosphere or (in Apple) through the phloem. Such exogenous water in the intercellular spaces of the fruit may cause cells to swell, so cracking the fruit or it may result in a bursting of the cells. A plea is made for further light microscope studies of the development of symptoms of calcium deficiency:
- W. Simon,1978. The symptoms of calcium deficiency in plants. New Phytologist, Volume 80, Issue 1, pages 1–15
Increases growth, increased P, K and Ca uptake
A glasshouse experiment was carried out to study the effect of ammonium supply [0 and 1.5 mmol L‐1 in the nutrient solution, whereas total nitrogen (N) concentration, was 9.5 mmol L‐1] on nutrient uptake, leaves, and xylem sap composition and growth of bean plants in sand culture. Ammonium supply caused higher nitrogen, phosphorus (P), potassium (K), and calcium (Ca) uptake. However, K, Ca, and magnesium (Mg) concentrations in the plants (in xylem sap and leaves) were lower when ammonium was supplied. Plants vegetative growth was higher with ammonium supply than without it, especially after four weeks of cultivation:
- J. Sarro, J. M. Sánchez & J. M. Peñalosa, 1998. Influence of ammonium uptake on bean nutrition. Journal of Plant Nutrition, Volume 21, Issue 9, pages 1913-1920
Increases yield, dry matter
Soybean (Glycine max (L.) MERR. CV. ‘Amsoy’) plants were grown for 40 days in nutrient solution at various concentrations of ammonium. Maximum yield of dry matter was obtained at a concentration of 715 μM. Further increase in the concentration of ammonium resulted in a reduction in growth due to ammonium toxicity which affected both root and shoot development. The pattern of nitrogen accumulation in tops was consistent with the multiphasic uptake of ammonium and can be represented by 2 phases in the range 1.78 X 10-5-3.57 x X 10-3 M of ammonium:
- A. Joseph, Tang Van Hai and J. Lambert, 1976. Effect of ammonium concentration on growth and nitrogen accumulation by soybean grown in nutrient solution. BIOLOGIA PLANTARUM, Volume 18, 339-343
The growth and chemical composition of Ricinus communis cultivated hydroponically on 12 mol m – 3 NO3-N were compared with plants raised on a range of NH4+-N concentrations. At NH4+-N concentrations between 0.5 and 4.0 mol m-3, fresh- and dry weight yields of 62-d-old plants were not significantly different from those of the NO3-N controls. Growth was reduced at 0.2 mol m-3 NH4+-N and was associated with increased root. Shoot and C: organic N ratios, suggesting that the plants were N-limited. At 8.0 mol m-3 NH4+-N, growth was significantly restricted, and the plants exhibited symptoms of severe NH4+ toxicity’. Plants growing on NH4+-N showed marked acidification of the rooting medium, this effect being greatest on media supporting the highest growth rates. Shoot carboxylate content per unit dry weight was lower at most NH4+-N concentrations than in the NO3-N controls, although it increased at the lowest NH4+-N levels. Root carboxylate content was comparable to the two N sources, but also increased substantially at the lowest NH4+-N levels. N source had little effect on inorganic-cation content at the whole-plant level while NO3- and carboxylate were replaced by Clmultimap as the dominant anion in the NH4+-N plants. This was reflected in the ionic composition of the xylem and leaf-cell saps, the latter containing about 100 mol m-3 Cl- in plants on 8.0 mol m-3 NH4+. Xylem-sap organic-N concentration increased more than threefold with NH4+-N (with glutamine being the dominant compound irrespective of N source) while in leaf-cell sap it increased more than 12-fold on NH4+-N media (with arginine becoming the dominant species). In the phloem, N source had little or no effect on inorganic-cation, sucrose or organic-N concentrations or sap pH, but sap from NH4+-N plants contained high levels of Cl- and serine. Collectively, the results suggested that the toxic effects of high NH4+ concentrations were not the result of medium acidification, reduced inorganic cation or carboxylate levels, or restricted carbohydrate availability, as is commonly supposed. Rather, NH4+ toxicity in R. communis is probably the result of changes in protein N turnover and impairment of the photorespiratory N cycle:
Allen, S., and Smith, J A. C. 1986. Ammonium Nutrition in Ricinus communis : Its Effect on Plant Growth and the Chemical Composition of the Whole Plant, Xylem, and Phloem Saps. Journal of Experimental Botany, Volume: 37, Issue: 11, Pages: 1599-1610
The effects of ammonium on the activity of sucrose synthase (SS) in the roots of pea (Pisum sativum L.) plants were studied. On the medium containing 14.2 mM (NH4)2SO4, SS activity increased by 20–200% for 10–20 days of plant growth as compared to the roots of plants growing without nitrogen. Illuminance affected the degree of effects. Under natural illumination, ammonium changed SS activity not only in sunny days (up to 25 klx) but also in cloudy days (3–6 klx) but to a lower degree. Under stable low light (2.5 klx), ammonium did not affect SS activity. In the in vitro experiments, at (NH4)2SO4 concentrations from 0 to 1 mM, SS activity was suppressed (up to 10%), whereas 1–37.5 mM (NH4)2SO4, it was increased (up to 50%):
- Nikitin, R. Bruskova, T. Andreeva, S. Izmailovm,2010. Effect of ammonia on sucrose synthase in pea roots. Russian Journal of Plant Physiology, Vol. 57, No. 1. pp. 69-73
This work was carried out to study the effect of two nitrogen levels, 250 and 500 g of actual nitrogen per avocado tree per year. The nitrogen sources were calcium nitrate (as soil application) and urea (as foliage form).
Nitrogen fertilization gave a highly significant increase in tree yield (kg/tree) in most treatments. Moreover, urea sprays seemed to be more effective on the yield than calcium nitrate added to the soil at the same nitrogen level. The 500 g nitrogen level of both sources gave a higher yield increase than 250 g nitrogen. Nitrogen fertilization gave a slight increase in mean avocado fruit weight and size, while urea sprays seemed to be more efficient in increasing the average fruit weight and size. A small decrease in flesh oil content occurred as a result of nitrogen fertilization:
A.B.Abou Aziz, I. Desouki, M.M. El-Tanahy, 1975. Effect of nitrogen fertilization on yield and fruit oil content of avocado trees. Scientia Horticulturae, Volume 3, Issue 1, Pages 89–94
Critical during flower development, especially during flower opening
Rose (Rosa hybrida L.) plants grown for cut-flower production in greenhouses produce flowers in flushes year-round. The aim of the current study was to measure uptake rates of nitrogen and potassium by roses. Rose plants var. ‘Kardinal’ were grown in the greenhouse in aero-hydroponics nutrient solution with 3 mM nitrate (NO3)-N and 1 mM potassium (K)…..There was a cyclic rhythm of both the nutrients’ influx rates over time, with a decline in uptake after shoot harvest, and an increase during flower development, with maximal values towards flower opening.
M Silberbusha, b, J.H Lietha, 2004. Nitrate and potassium uptake by greenhouse roses (Rosa hybrida) along successive flower-cut cycles: a model and its calibration. Scientia Horticulturae, Volume 101, Issues 1–2, Pages 127–141.
Increase in yields, dry weight
Two factorial fertilizer trials involving four levels of nitrogen and four levels of potassium were carried out on sweet potato to gain a better understanding of the way in which fertilizer influences growth and yield. Under conditions of continuous cropping, nitrogen (N) had a greater influence on growth and yield than did potassium (K). N fertilization up to a rate of 225 kg N ha−1 increased tuber yield, mean tuber weight, total plant dry weight, dry weight of all plant components, leaf area index, leaf area duration, number of leaves per plant, mean leaf area per leaf, crop growth rate; and, for some periods, leaf area ratio (LAR) and relative growth rate. N reduced number of tubers per plant early in the crop. K fertilization up to a rate of 375 kg K ha−1increased tuber yield, number of tubers per plant, mean tuber weight, total plant dry weight, mean leaf area per leaf and harvest index. It reduced the percentage dry weight of tubers and LAR in Trial 2.
It is suggested that N influenced yield by increasing leaf area duration which in turn increased mean tuber weight and hence tuber yield. K influenced tuber yield via an increase in the proportion of dry matter diverted to the tubers and a rise in tuber number per plant. The effect of K occurred by 7 weeks after planting and it is suggested that K fertilizer be applied early in the crop life:
R.Michael Bourke, 1985. Influence of nitrogen and potassium fertilizer on growth of sweet potato (Ipomoea batatas) in Papua New Guinea. Field Crops Research, Volume 12, Pages 363–375.
Increase in quality of produce
Effects of potassium levels on fruit quality were evaluated on ‘Tiantian No. 1’ muskmelon (Cucumis melo, cv. reticulatus Naud.) in soilless medium culture under a greenhouse. Three potassium levels, K120(insufficient), K240 (suitable), and K360 (excessive) in nutrient solution, which represent 120, 240, and 360 mg l−1 of potassium (K), respectively, were applied. At potassium level of 240 mg l−1, the concentrations of total sugar, total soluble solids, glutamic acid, aspartic acid, alanine, and volatile acetate components (n-amyl acetate, 2-butoxyethyl acetate) significantly increased in fruit flesh, which should improve the taste and aroma of muskmelon. However, no significant difference in fruit appearance or size was recorded among the treatments. Favorable quality of muskmelon in soilless medium culture were achieved when potassium level was adjusted to near 240 mg l−1 in nutrient solution:
Duo Lin1, Danfeng Huang, Shiping Wang, 2004. Effects of potassium levels on fruit quality of muskmelon in soilless medium culture. Scientia Horticulturae, Volume 102, Issue 1, Pages 53–60.
Increases chlorophyll, photosynthesis, protects against oxidative stress
Houttuynia cordata Thunb. is an edible herb with a variety of pharmacological activities, but only limited information is available about its response towards potassium supplementation. Sterile plantlets were cultured in media with different potassium levels, and parameters related to growth, foliar potassium, water and chlorophyll contents, photosynthesis, transpiration, H2O2 contents and antioxidative enzyme activities were determined after a month. Results showed that 1.28 mM potassium was the optimum for H. cordata as highest values of dry weight, shoot height, root length and number were obtained at this concentration. The optimum potassium concentration resulted in the maximum net photosynthetic rate which could be associated with the highest chlorophyll content rather than limited stomatal conductance. The supply of surplus potassium resulted in higher content of foliar potassium, but negatively correlated with the biomass. Both potassium starvation (0 mM) and high potassium (>1.28 mM) could lead to water loss through high transpiration rate and low water absorption, respectively, and resulted in H2O2 accumulation and increased activities of catalase and peroxidase, which suggested induction of oxidative stress. Moreover, H. cordatashowed the minimum of H2O2 content and the maximum of superoxide dismutase activity on 1.28 mM potassium, implying its role in inducing tolerance against oxidative stress:
- Wen Xua, 1, Yu Ting Zoua, 1, Amjad M. Husainib, Jian Wei Zenga, Lin Liang Guana, Qian Liua, Wei Wua, 2011. Optimization of potassium for proper growth and physiological response of Houttuynia cordata Thunb. Environmental and Experimental Botany, Volume 71, Issue 2, Pages 292–297.
Increased seed yield
A 2-year field study was conducted to determine the effect of N fertilization on various aspects of linseed growth, including phenological stages, seed yield and yield components, the contribution of yield components to seed yield, biomass growth rate, and nitrogen uptake rate. Three different cultivars were used (Creola, Livia, and Lirina) and three rates of N fertilization were applied (0, 40 and 80 kg ha−1). N fertilization was found to increase seed yield by an average of 37% above the control rate over the 2-year study period. Application of N affected yield components, especially the seed weight per plant, the number of capsules per plant, the number of capsules m−2, and the number of seeds per plant, which were increased by an average of 54, 62, 45, and 56% respectively compared with the control. Phenological stages (time to reach flowering, seed maturity, and seed filling period) were also affected by N fertilization and the seed filling period was increased by 10% compared with the control. Plant height was also increased with N application, and cultivar height differences were also apparent. Biomass growth rate, economic growth rate, and seed growth rate were all increased with N application, but much higher increases were found in the N uptake rate, economic N rate, and seed N uptake rate. Seed yield was correlated with the yield components, seed filling period, biomass growth rate (BGR), economic growth rate (EGR), seed growth rate (SGR), and nitrogen uptake rate (NUR). Also, NUR was negatively correlated with the economic N uptake rate (ENUR) and seed N uptake rate (SNUR). In conclusion, the present study indicates that N fertilization promotes the growth of linseed, affecting the development and increasing the BGR, EGR, SGR, and also NUR, ENUR, and SNUR. These are important physiological determinants of seed yield that can be used as additional selection criteria for yield improvements:
Christos A. Dordas, 2010. Variation of physiological determinants of yield in linseed in response to nitrogen fertilization. Industrial Crops and Products, Volume 31, Issue 3, Pages 455–465.
Increased yield and quality of fruit
A fixed field experiment was designed to study the effects of nitrogen (N) and potassium (K) fertilizers applied to optimize the yield and quality of typical vegetable crops. Application of N and K fertilizers significantly increased the yields of kidney bean. The largest yields were obtained in the first and second years after application of 1 500 kg N and 300 kg K2O ha−1. Maximum yields occurred when standard rates of N and K (750 kg N and 300 kg K2O ha−1) were applied. Application of K fertilizer was often associated with increased sugar concentrations:
Zhao-Hui LIU, Li-Hua JIANG, Xiao-Lin LI, R. HÄRDTER, Wen-Jun ZHANG, Yu-Lan ZHANG, Dong-Feng ZHENG, 2008. Effect of N and K Fertilizers on Yield and Quality of Greenhouse Vegetable Crops. Pedosphere, Volume 18, Issue 4, Pages 496–502.
Cobalt is found to be essential for the proper growth of nodulated plants of Casuarina cunninghamiana and Myrica galein a nitrogen-free rooting medium. If cobalt is not supplied, the plants develop symptoms of nitrogen deficiency; under the conditions of the experiments such symptoms became pronounced during the second season of growth of these perennial plants. No cobalt requirement could be detected in non-nodulated plants of Alnus and Myrica supplied with nitrate or ammonium-nitrogen, and this suggests that in nodulated plants the need for cobalt is confined to the nodules. Vitamin B12 analogs are shown to be present in the nodules in relatively large amounts when cobalt is supplied, their formation being attributed to the endophytes, which may, therefore, require cobalt for their growth. The significant reduction in fixation of atmospheric nitrogen in cobalt-deficient nodules may be due to a retarded growth of the endophyte, though this is not the only possibility. The cobalt relation of these non-legumes appears to be fundamentally similar to that of legumes:
Cobalt has also been demonstrated to be an essential element required by certain blue-green algae. However, while it has been shown that cobalt will materially increase the elongation of stem segments in the presence of sugars, there is no conclusive proof that the element is essential to the growth of higher plants. the evidence summarized here shows that a minute amount of cobalt supplied in the nutrient solution to rubber plants grown in sand significantly improved growth. It indicates that cobalt has a beneficial effect on the growth of a higher plant; but this, in itself, does not prove it to be an indispensable nutrient element:
- W. Bolle-jones & v. R. Mallikarjuneswara . A beneficial effect of Cobalt on the Growth of the Rubber Plant (Hevea brasiliensis).
Marston, H. R., and Lee, H. J., 1952.Nature, Volume 170, No 791 Anderson, G. P., and
Andrews, E. D., 1952. Nature, Volume 170, No 807.
Holm-Hansen, O., Gerloff, G. C., and Skoog, 1954. F. Physiol. Plant, Volume 7, No 665
Miller, C. O., 1954. Plant Physiol., Volume 29, No 79.
Thimann, K. V., Amer. 1956. J. Bot., Volume 43, No 241.
Galston, A. W., and Siegel, S. M. , 1954. Science, Volume 120, No 1070.
Treatment of pigeon pea seed with cobalt nitrate (500 tug kg‐1 seed) increased plant height, number of branches, leaves, total dry matter, and yield. The chlorophyll content, crop growth rate, relative growth rate, and net assimilation rate also increased significantly. Peanut seed treatment with cobalt nitrate (500 mg kg‐1 seed) followed by two foliar sprays before and after flowering (500 mg L‐1 water) increased plant height, leaf number, and total dry matter. Pod yield, shelling percentage, test weight, and harvest index increased significantly. In both crops nodule number and leghaemoglobin content also increased. Seed inoculation with Rhizobium alone was not sufficient to reach maximum yield in both crops grown on the soil tested. Cobalt apparently improves nitrogen fixation by rhizobium, resulting in higher yield:
- Shiv Raj, 1987. Cobalt nutrition of pigeon pea and peanut in relation to growth and yield. Journal of Plant Nutrition, Volume 10, Issue 9-16, pages 2137-2145.
Pre-sowing treatment of buckwheat seed in solutions containing 0-04-0-08%, cobalt nitrate for 24 h, in addition to a basal dressing of 30 kg each of N, P2O5 and K2O/ha, increased chlorophyll content and photosynthesis in plants, and resulted in yields of 11.3-12.3 hkg grain/ha (12.1-23.1% increase), compared with 9-9 hkg on plots given the basal dressing only; the highest increases were given by 0.04% cobalt nitrate.-M.S.M:
ELAGIN, I. N., 1970. The effect of cobalt on the buckwheat chlorophyll content, photosynthesis intensity and yield. Doklady Vsesoyuznoi Akademii sel’sko-khozyaistvennykh Nauk im V. I. Lenina No. 7 pp. 22-3
Two experiments were carried out included a pot preliminary greenhouse experiment to choose the most effective levels of cobalt on broccoli growth and yield and a field experiment to evaluate the vegetative growth, heads quantity and quality as well as nutrients content of broccoli (Brassica oleracea var.italica) as affected by using different levels of cobalt concentrations. The obtained results showed that the addition of 6 ppm cobalt had a significant positive effect on broccoli growth, head yield and quality. Higher concentrations exerted hazards effect. The content of Mn, Zn and Cu in heads increased with the increase in cobalt application. On the other hand, the opposite trend was observed with Fe. Cobalt rate at 6 ppm increased the concentrations of N, P and K, but further increasing in cobalt concentrations addition decreased N, P and K in broccoli heads:
Nadia Gad and M.R. Abd El-Moez. Broccoli growth, yield quantity and quality as affected by cobalt nutrition. Plant Nutrition Dept.,
Two legumes, lentil, and chickpea, were cultivated in nutrient solutions: Fe lacking or containing 30 μM Fe. After 12 days of Fe starvation, lentil showed a severe yellowing of young leaves, a large decrease in chlorophyll concentration, and a significant decline in plant biomass. Chickpea showed a better response than did lentil, primarily due to a stronger acidification capacity. Also, no chlorosis symptoms were observed in chickpea until the end of treatment. There was no significant difference in potassium uptake between the two species, but an enrichment of the young leaves at the expense of the old ones was noted in chickpea, and to a lesser extent, in lentil, when they were exposed to Fe deficiency. Moreover, this constraint led to a significant decrease of iron content in the two legumes. However, chickpea displayed higher accumulation levels of HCl-extractible iron in young and old leaves than did lentil. This protection of young leaves against K+ and Fe2+ impoverishment confers to these organs the capacity to preserve their chlorophyll status and their photosynthetic integrity. Furthermore, the better performance of chickpea under conditions of low Fe availability could be partially related to its iron seed reserves, higher than those of lentil:
Henda Mahmoudia, Riadh Ksouri, Mohamed Gharsalli, Mokhtar Lachaâl,2005. Differences in responses to iron deficiency between two legumes: lentil (Lens culinaris) and chickpea (Cicer arietinum). Journal of Plant Physiology, Volume 162, Issue 11, Pages 1237–1245.
Papaya (Carica papaya L.) cultivar ‘Honeydew’ was grown in pure sand with complete nutrition and at deficient levels of iron (0.014 or 0.056 mg l−1), zinc (0.0065 or 0.013 mg l−1) or boron (0.0033 or 0.033 mg l−1). The symptoms of deficiencies of iron and boron appeared in young leaves, and those of zinc in middle leaves. The depression in growth was maximum in iron deficiency and least in zinc deficiency. The affected leaves from plants which were acutely deficient in iron, zinc or boron contained as little as 85 μg iron, 13 μg zinc, and 6.7 μg boron g−1 dry matter, respectively, whereas comparable leaves from typical plants contained 140 μg iron, 22.4 μg zinc and 17.3 μg boron g−1 dry matter, respectively:
B.D. Nautiyal, C.P. Sharma, S.C. Agarwala,1986. Iron, zinc and boron deficiency in papaya. Scientia Horticulturae, Volume 29, Issues 1–2, Pages 115–123.
The effects of Fe deficiency (whether direct or bicarbonate-induced) on plant morphology, growth parameters, photosynthesis-related pigment contents, gas exchange, and water relations were addressed in two contrasting chickpea varieties (INRAT88 and Chetoui, respectively tolerant and sensitive to Fe deficiency). A marked decrease in the whole plant Fe content was observed in the Fe deprived plants of both varieties, especially the bicarbonate-treated ones, which showed a slower growth development and water deficit stress symptoms (increased leaf tissue osmolality associated with decreased shoot height, increased leaf mass to area ratio, and decreased moisture content). Both Fe shortage and bicarbonate addition resulted in both varieties in the decline of the photosynthetic pigment contents, contributing to lower photosynthetic efficiency (φc) and lower net photosynthesis (A). Fe deficiency reduced the water use efficiency and physiological availability of water too. However, INRAT88 was more tolerant to Fe deficiency than Chetoui, by maintaining a higher growth rate associated with lower respiration rate (RD), higher chlorophyll a and b concentrations, higher A, lower transpiration rate (E) and a higher water use efficiency (A/E). The present data suggest that the efficient utilization of Fe for the synthesis of chlorophyll together with the active control of electron-transport chains at chloroplasts (high A) and mitochondrial (small RD) may account for the greater tolerance of INRAT88 to direct Fe deficiency. Further investigations on oxidative stress and ROS generation, or about photorespiration would be helpful for a better understanding of their interaction with Fe deficiency in this grain legume:
Henda Mahmoudi, Hans-Werner Koyro, Ahmed Debez, Chedly Abdelly, 2009. Comparison of two chickpea varieties regarding their responses to direct and induced Fe deficiency. Environmental and Experimental Botany, Volume 66, Issue 3, Pages 349–356.
Reduction of iron (Fe3+ → Fe2+) at the root of Glycine max. (L.) Merrill var. Hawkeye soybean was studied to identify areas of reduction in the root. Sites of iron reduction were indicated by the formation of a Prussian or Turnbull’s blue precipitate. This blue precipitate formed whenever the iron in either FeEDDHA or potassium ferricyanide was reduced by the plant. Where FeEDDHA and potassium ferricyanide were supplied together in the nutrient solution, a blue precipitate appeared in epidermal areas. This precipitate appeared in the endodermal areas of the root when FeEDDHA was supplied to the plant 20 hours before placing them in a ferricyanide solution. Reduction was most pronounced between the regions of root elongation and root maturation at both the epidermis and the endodermis. Reducing capacity was greatest in the young lateral diarch roots indicating that these roots contribute significantly to the ability of the plant to take up iron. A reductant which exuded from the roots of an iron deficient plant was capable of reducing approximately 360 µg of inorganic iron. The ability of some plants to reduce iron may partially explain why they can obtain iron from synthetic chelates and can utilize iron in calcareous soils more efficiently than other plants:
- E. Ambler, J. C. Brown and H. G. Gauch, Sites of Iron Reduction in Soybean Plants. Agronomy Journal, Vol. 63 No. 1, p. 95-97.
Severely iron-deficient peanuts (Arachis hypogaaea L.) grown on calcareous soils in central Thailand failed to nodulate until given foliar iron applications. Glasshouse experiments were conducted on two cultivars (Tainan 9 and Robut 33–1) to identify which stage of the nodule symbiosis was most sensitive to iron-deficiency.
Iron-deficiency did not limit growth of soil or rhizosphere populations of peanut liradyrhizobium. Similar numbers of root nodule initials formed in the roots of both control and iron-sprayed plants, showing that iron-deficiency did not directly affect root infection and nodule initiation. Plants sprayed with iron produced greater numbers of excisable nodules and carried a greater nodule mass than untreated plants. Five days after iron application, nodules on sprayed plants of CV. Tainan 9 contained 200–fold higher bacteroid numbers per unit weight and 14–fold higher concentrations of leghaemoglobain. The onset of nitrogenase activity was also delayed by iron deficiency in both cultivars. Tainan 9 appeared more sensitive to iron-deficiency than Robut 33-1 in terms of nodule mass produced, but both cultivars showed the same effect of iron-deficiency on nitrogenase activity per plant.
It is concluded that the failure of the infecting rhizobia to obtain adequate amounts of iron from the plant results in arrested nodule development and a failure of nitrogen fixation:
- W. O’HARA, M. J. DILWORTH, N. BOONKERD, P. PARKPIAN,1988. Iron-deficiency specifically limits nodule development in peanut inoculated with Bradyrhizobium sp. New Phytologist, Volume 108, Issue 1, pages 51–57.
Field and greenhouse experiments were conducted on a Charlottetown fine sandy loam soil containing 0.28 ppm hot‐water‐soluble (hws) B. Broccoli, Brussels sprouts, and cauliflower grown without added B showed B deficiency symptoms in the form of yellowing of leaves and in the case of cauliflower purplish colored inward curled leaf edges were also noted under greenhouse conditions. Under field conditions, however, only broccoli showed symptoms of B deficiency in the form of browning of lower leaf edges. Application of B increased plant growth about 3‐fold under greenhouse conditions while in the field experiment B increased the yield of broccoli and cauliflower by about 20%. The decreased yields of broccoli, Brussels sprouts and cauliflower with B deficiency leaf disorders under greenhouse conditions were associated with plant tissue B concentrations of 2.4, 6.6 and 4.2 ppm, respectively, in the three crops. Under field conditions, B deficiency symptoms in broccoli, and reduced yields in broccoli and cauliflower were associated with 7.8 to 9.1 ppm B in the leaf tissue. Liming the soil from pH 6.0 to 6.6 increased the yield of cauliflower but had no effect on broccoli and Brussels sprouts yields or the concentration of B in broccoli and cauliflower tissue:
Umesh C. Gupta & J. A. Cutcliffe,1975. Boron deficiency in cole crops under field and greenhouse conditions. Communications in Soil Science and Plant Analysis, Volume 6, Issue 2, pages 181-188.
Two experiments were conducted in which asparagus (Asparagus officinalis L.) was grown in sand culture with boron (B) levels varied by applying 11 rates of B in nutrient solution (0–6.4 mg l−1) in one experiment and 4 rates (0.8–12 mg l−1) in a second experiment. Maximum plant growth occurred when the B concentration in solution was 1.6 mg l−1. Shoot growth increased rapidly as the B concentration in the shoots rose to 50 μg g−1 DM. Maximum shoot growth occurred in the range 120–300 μg g−1 DM with a comparatively little decline in growth up to 400 μg g−1 DM. Root growth dropped when B concentrations in the root rose above 40 μg g−1DM. The increased levels of B had no effect on the total plant concentration of nitrogen, phosphorus, copper and molybdenum but the concentrations of potassium, sulfur, calcium, magnesium, sodium, manganese and zinc increased. The effect on iron concentration was variable and inconclusive. Sulfur, potassium, sodium and zinc concentrations increased in the roots and except for a decline in potassium levels they all remained constant in the shoots. Calcium, magnesium and manganese concentrations rose in both the shoot and roots. This work confirms the high B requirement of asparagus:
J.A. Douglas, J.M. Follett, R.A. Littler, 1989. Boron requirement of asparagus seedlings grown in sand culture. Scientia Horticulturae, Volume 38, Issues 1–2, Pages 33–42.
Poor fruit quality due to boron deficiency was first reported over 40 years ago from Finland and New Zealand. Since then boron deficiency in apples has been recognized in many other countries including Australia, Austria, Canada, Greece, France, Italy, Japan, Korea, Norway, South Africa, Switzerland and the USA. Apart from shoot dieback, the symptoms most commonly reported are internal and external cork formation in the fruit and the development of small, deformed and cracked fruit; a mild expression of any of these symptoms can markedly reduce fruit quality. Apart from isolated claims, there has previously been no clear indication that boron deficiency occurs on apples in the UK; this is strange given the occurrence of boron deficiency in many other countries where apples are grown. It was one of the objects of this study to determine whether boron applications to apples in the UK could be beneficial.
Although current research indicates that bitter pit is primarily due to a shortage of calcium in the fruit, past research has implicated not only calcium but also boron. In fact, early work has indicated that bitter pit, which was and probably still can be, confused with external cork, could be cured by boron. Faust and Shear (1968) in their excellent review of corking disorders noted as many papers reporting beneficial effects of boron on bitter pit as those in which boron was not related to the disease.
Faust and Shear (1968) and Woodbridge, Wieneke and Fuhr (1973) have suggested that boron applications can improve the mobility of calcium in the apple tree. Their work indicated that when a tree is marginally deficient in boron, but reasonably well supplied with calcium, boron can have a beneficial effect by promoting calcium movement to the fruit: on the other hand, when boron is in good supply, no beneficial effect can be expected. One objective of this work on the boron nutrition of apples was to study the effect on the bitter pit of sprays of boron (as Solubor, a sodium borate with the approximate composition Na2B8O134H2O) and calcium (as calcium nitrate) applied either singly or combined to fruiting trees of the variety Egremont Russet. However, in the first year of this trial, a marked reduction was also recorded in the incidence of fruit cracking:
- M. Shorrocks, D. D Nicholson, The influence of boron deficiency on fruit quality. International society for horticultural science.
Soil applications of boron (B) had little effect on yield of carrots (Daucus carota L.) and beets (Beta vulgaris L.) in a field study. However, in a greenhouse study B significantly increased the yield of carrots. Boron deficiency impaired the quality of both crops. Boron deficient beets had brown tops, and roots were rough, scaby, and off color. There was a depression on the sides of most of the beetroots and cut sections of affected roots were darker and necrotic compared to bright purplish red roots grown with sufficient B. In carrots; B deficiency resulted in yellow tops, and the roots were both rough and small with a distinct white core in the middle. Leaf tissue B concentrations of 32–40 μg/g in beets and 22–28 μg/g in carrots were related to B deficiency. Tissue B levels as high as 121 μg/g in beets and 149 μg/g in carrots were not associated with any B toxicity. Applications of B had no effect on tissue Ca and Mg concentration in the two crops:
Umesh C. Gupta & J. A. Cutcliffe,1985. Boron nutrition of carrots and table beets are grown in a boron deficient soil. Communications in Soil Science and Plant Analysis, Volume 16, Issue 5, pages 509-516.
Rice plants were grown in sand cultures with a nutrient solution including boron at 0, 1, 2.5 and 5 ppm concentrations.
In general, the supply of boron improved the pollen vitality of rice flowers. It was stimulating up to 2.5 ppm concentration in the nutrient solution, beyond which (i.e., at 5 ppm) inhibitory effects appeared. The availability of boron also increased the yield of rice grains in the same order.
Stimulating effects of boron may be linked with greater availability of sugars, increased enzymatic activity, and respiration which favored the better growth of pollen. Inhibitory effects of stronger concentration of boron (5 ppm) may be related to physiological depression and injury to protoplasm itself:
- K. Garg, A. N. Sharma and G. R. S. S. Kona, 1979. Effect of boron on the pollen vitality and yield of rice plants (Oryza sativa L. var. Jaya). PLANT AND SOIL, Volume 52, 591-594.
Boron deficiency symptoms in snap beans (Phaseolus vulgaris L.) showed as a general yellowing of tops with slow flowering and pod formation while toxicity caused reduced growth and burned dark brown older leaves, especially on the edges. In radish (Raphanus sativus L.)f B deficiency resulted in roots which were brown upon cutting and had thick periderm. Even at 4 ppm applied B, no apparent B toxicity was noted in radish. The plant tissue B levels of less than 9 to 12 ppm were associated with B deficiency in radish and beans; and greater than 125 ppm with B toxicity in beans. In tomatoes (Lycopersicon esculentum, Mill) B deficiency resulted in reduced growth while B toxicity at 4 ppm applied B caused poor and slow germination. Boron deficiency and toxicity in tomatoes were related to < 12 and > 172 ppm B, respectively, in tissue. No B deficiency was noted in corn (Zea mays L.) and timothy (Phleum pratense L.). The B toxicity in these two crops appeared as marginal burning and dark brown tips of older leaves and was related to greater than 98 and 176 ppm tissue B in corn and timothy, respectively:
Umesh C. Gupta, 1983. Boron deficiency and toxicity symptoms for several crops as related to tissue boron levels. Journal of Plant Nutrition, Volume 6, Issue 5, pages 387-395.
To induct manganese-deficiency effects in tomato (Lycopersicon esculentum) var. Pusa Ruby, plants were grown in the pure sand at two deficient i.e. 0.0011 and 0.055 mg/liter and one adequate, 0.55 mg/liter levels of manganese. Manganese deficiency at 0.0011 mg Mn/liter reduced the fruit yield more than the biomass. At low manganese levels, the concentration of Mn, chlorophyll, starch, Hill activity and acid phosphatase were decreased, whereas the concentration of sugars, activity of peroxidase, catalase and ribonuclease were increased significantly in tomato leaves. The visible effects of low manganese deficiency were pronounced on middle leaves under acute deficiency condition i.e. at 0.0011 mg Mn/liter. A significant decrease in the concentration of ascorbic acid, soluble proteins, starch, sugars and high phenols reflect poor quality of tomato fruits under manganese deficiency:
Dube B.K., Chatterjee C., 1999. Effect of manganese deficiency on fruit quality in tomato. Indian Journal of Horticulture, Volume: 56, Issue: 3, pp 242 -246.
Manganese deficiency as indicated by visual symptoms and small tissue manganese concentrations was associated with substantial reductions in the number and total weight of fruit per vine in a commercial kiwifruit orchard. The mean weight per fruit and the percentage of the fruit of exportable size were not affected. Fruit from deficient manganese vines had a slightly higher mean total solids content after 121 days storage at 0.5° to 1°C than fruit from healthy vines, but the disorder did not reduce fruit firmness.
Variations in the severity of leaf symptoms, leaf and fruit manganese concentration, and fruit yield were associated with variation in the pH of the surface soil within the range 6.8 to 7.3. Maximum yields of fruit were associated with pH values <6.9, and manganese concentrations >3.5 μg g–1 dry matter in the fruit and >33 μg g–1 dry matter in youngest fully expanded leaves on aerial canes. DTPA extraction of air‐dried samples of surface soil did not provide a useful guide to plant‐available manganese:
- J. Asher, G. S. Smith, C. J. Clark & N. S. Brown, 1984. Manganese deficiency of kiwifruit (Actinidia chinensis Planch.). Journal of Plant Nutrition, Volume 7, Issue 10, pages 1497-1509.
Manganese deficiency symptoms are more often observed in crops at early stages of growth since Mn2+ can be easily mobilized from the surface soil. The objectives of this study were to evaluate some of the traditional rotation crops grown in Hungary for tolerance to low external Mn2+ levels and to determine the critical tissue concentration for Mn2+ deficiency during early stages of growth. Indicator plants of sunflower (Helianthus annuus L.) were grown with NPKCaMg-fertilization induced of 0.0425–0.0700 g kg−1; of tobacco (Nicotiana tabacum L.) 0.0237–0.0337 g kg−1; of triticale (x Triticosecale W.) 0.0103–0.0327 g NH4-acetate + EDTA extractable soil Mn2+ kg−1; and were grown for 73, 50, and 191 days. The minimum Mn2+ concentration required in soil nutrient contents was 0.0425 g kg−1 for sunflower, 0.0243 g kg−1 for tobacco, and 0.0103 g kg−1 for triticale. Sunflower, tobacco and triticale achieved optimum growth from 0.048 to 0.065 g Mn2+ kg−1, from 0.0249 to 0.0321 g Mn2+ kg−1, and from 0.0287 to 0.0296 g Mn2+ kg−1, respectively. Critical ABP’s dry weight Mn2+ concentration at early stages of growth was 0.0536 g kg−1 in sunflower, 0.458 g kg−1 in tobacco, and 0.1938 g kg−1 in triticale. Our results demonstrate that the tolerance to low external Mn2+ (triticale <0.0302 g kg−1; sunflower <0.0562 g kg−1; tobacco <0.0693 g kg−1) and the critical tissue Mn2+ levels for deficiency varied significantly among crop species tested:
Márton László, 2008. Manganese requirement of sunflower (Helianthus annuus L.), tobacco (Nicotiana tabacum L.) and triticale (x Triticosecale W.) at an early stage of growth. European Journal of Agronomy, Volume 28, Issue 4, Pages 586–596.
The effects severe, moderate or slight manganese (Mn) deficiency on tillering and development of Galleon barley were examined in the field and growth-cabinet experiments. Manganese deficiency is delayed maturity in both areas and growth-cabinet experiments. In the field, Mn-deficient plants were still tillering when the plants in plots receiving Mn fertilizer had ceased tillering, and their stems were elongating. In growth-cabinet experiments, plants with moderate or severe Mn deficiency did not reach the stem elongation stage of development and continued to tiller until they died.
The pattern of tillering was altered by Mn deficiency. Moderate deficiency decreased the rate of tiller emergence without affecting the speed of leaf emergence on the main culm. Therefore, at early tillering, deficient plants had fewer tillers. Manganese deficiency extended the period of tillering, and after control plants ceased tillering and their stems began elongating, deficient plants continued to tiller, eventually reaching the number of tillers of the control plants. Moderate and severe Mn deficiency prevented stem elongation and reproduction and plants continued to tiller. Finally, average Mn-deficient plants had produced significantly more tillers than control plants or slightly deficient plants. Severe Mn deficiency resulted in the death of plants before any increased tiller production.
Manganese status affected apical development. When moderately Mn-deficient plants had one tiller, the main stem apex was at the double-ridge stage, compared with four tillers on the control plants which were at the late double-ridge or triple-mound stage. When the number of tillers of the Mn-deficient plants had increased to that of the control plants, the apex of the main stem was dead (shriveled and dry) in the deficient plants, while that of the controls was at the dawn primordium stage.
There was no difference in grain yield of slightly Mn-deficient and control plants, even though early tillering had been depressed and shoot biomass at maturity was lower in the former. Although moderately Mn-deficient plants produced greater number of tillers than control plants, these tillers did not produce any heads:
Nancy E. Longnecker1, Robin D. Graham, Gavan Card, 1991. Effects of manganese deficiency on the pattern of tillering and development of barley (Hordeum vulgare c.v. Galleon. Field Crops Research, Volume 28, Issues 1–2, Pages 85–102.
Manganese toxicity in callus and seedlings of five cultivars of burley tobacco (Nicotiana tabacum L.) was examined to assess the feasibility of using in vitro approaches for improving Mn tolerance. Foliar chlorosis and necrotic spotting, indicative of Mn toxicity, were observed in seedlings grown in sand and exposed to elevated Mn concentrations. Manganese-induced growth reductions were apparent in all cultivars; however, Ky 15 and Ky 17 were significantly more sensitive than Ky 14. In the callus tissue, increasing the media Mn concentration resulted in tissue discoloration and reduced growth. Differences among cultivars were evident with Ky 15 and Burley 21 callus appearing to be more sensitive than Ky 10, Ky 14 and Ky 17. The Mn content in callus and seedlings increased to the same extent in all cultivars. There was an agreement between the callus and seedling growth responses to Mn stress only for some of the cultivars. The results suggest that Mn tolerance in tobacco is a manifestation of both cellular and whole plant characteristic:
J.F. Petolino1, G.B. Collins,1985. Manganese Toxicity in Tobacco (Nicotiana tabacum L.) Callus and Seedlings. Journal of Plant Physiology, Volume 118, Issue 2, Pages 139–144.
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