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91.
《Communications in Soil Science and Plant Analysis》2012,43(4):411-425
Abstract Sulfur, zinc, iron, copper, manganese, and boron application did not affect the seed yield or oil percentage of sunflower (Hilianthus annuus L.) on both dryland and irrigated soils in North Dakota in 1981. Field averages indicated significant Zn, Mn, and B uptake by sunflower at the 12‐leaf stage as a result of fertilization with these elements. Increased Zn uptake was also observed in the uppermost mature leaf at anthesis from zinc fertilization. Although sunflower yield from boron fertilization was not significantly different from the check, a trend was observed in which boron fertilization seemed to decrease sunflower yield. Sunflower yields from the boron treatment were the lowest out of seven treatments in three out of four fields. Also, sunflower yield from the boron treatment was significantly lower than both iron and sulfur treatments when all fields were combined. 相似文献
92.
The effect of source and sink manipulation on accumulation of micronutrients (Fe, Zn, Mn, Cu) and protein in wheat grains was studied in a field experiment and ear culture. The source and sink manipulation was obtained by reducing assimilate source (through defoliation and spike shading) or sink (through 50% spikelets removal) after anthesis in the field and by changing sucrose or NH4NO3 levels of the culture media in ear culture. In the field experiment, reducing source and sink generally increased Fe, Zn, Mn, Cu, and protein concentrations except defoliation which decreased Mn concentration. Grain yield as well as micronutrient and protein contents in grains were all reduced by reducing source and sink sizes, suggesting that the accumulation of micronutrients and protein in grains was restricted by source supply and sink capacity. In ear culture, the supply of 20 to 80 g L–1 sucrose increased grain weight and yield, but decreased grain Fe, Zn, Mn, Cu, and protein concentrations. The supply of 0.57 to 2.28 g L–1 NH4NO3 increased grain yield and the concentrations and contents of micronutrients and protein. All these results show that micronutrient and protein accumulation in grains can be affected by the source–sink relationship of carbohydrate and nitrogen. Adequate N supply can simultaneously increase grain yield and the accumulation of Fe, Zn, Mn, Cu, and protein. 相似文献
93.
94.
Aegilops kotschyi and Aegilops tauschii as sources for higher levels of grain Iron and Zinc 总被引:1,自引:0,他引:1
Micronutrient malnutrition affects a very large proportion of the world's population. For combating micronutrient malnutrition, biofortification through genetic manipulation has been proposed as an alternative to traditional fortification for increasing the bioavailable nutrient content of food crops. Wheat, being a staple food for a large section of the world's population, is targeted for increasing the Fe and Zn content in the grains. The cultivated germplasm of wheat does not have sufficient variability for grain Fe and Zn content but the wild species of wheat do show wider variation for grain micronutrient density. The analysis of Aegilops kotschyi and A. tauschii for Fe and Zn content in the grains using an atomic absorption spectrophotometer (AAS) indicated that the S and D genome species accumulate significantly higher iron and zinc in the grains than the cultivated wheats. One of the CIMMYT synthetics also had significantly higher Fe and Zn in the grains as compared with the cultivated wheats. Aegilops kotschyi as a promising source for Fe and Zn, is reported for the first time. A systematic programme to identify and utilize the additional sources for high Fe and Zn has been initiated. 相似文献
95.
Are synthetic hexaploids a means of increasing grain element concentrations in wheat? 总被引:5,自引:0,他引:5
Element concentration in wheat grains is an important objective of plant breeding programs. For this purpose, synthetic hexaploid
lines (Triticum durum ×Aegilops tauschii) have been identified as potential sources of high element concentration in grains. However, it is not known if these lines
reach higher element concentrations in grains as the consequence of a dilution effect due to lower grain yield. In addition,
most of the studies carried out with these lines did not evaluate above-ground element uptake. The objective of this study
was to improve understanding of grain element concentrations as a function of grain yield, element uptake and biomass and
element partitioning to grains in synthetic and conventional cultivars of wheat. One experiment with two standard sowing dates
was carried out under field conditions. Biomass, grain yield, and macronutrient(Ca, Mg, K, P and S) and micronutrient (Cu,Fe,
Mn and Zn) concentrations in grains and vegetative tissues were measured in two cultivars and one synthetic (chosen from ten
lines). The synthetic showed higher element concentration in grains, e.g. between 25 and 30% for Fe, Mn and Zn across sowing
dates, than cultivars while grain yield was similar or lower, depending on the sowing date. On the contrary, the synthetic
showed lower concentration of Cain grains. This line showed also higher uptake of Fe, Mn, K and P than cultivars. The superior
grain element concentration of the synthetic line was not only due to a dilution effect but also to a higher uptake efficiency.
Therefore, synthetics would bea valuable source of germplasm for increasing element grain concentration, at least in this
case for Fe, Mn, K and P.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
96.
Jared Barnes Brian Whipker Ingram McCall Jonathan Frantz 《Journal of plant nutrition》2016,39(13):1950-1957
‘Bouquet Purple’ pinks (Dianthus sp.) were grown in silica-sand culture to induce and photograph symptoms of nutritional disorders. Plants received a complete modified Hoagland's all-nitrate (NO3) solution. Nutrient-deficient treatments were induced with a complete nutrient formula minus one of the nutrients, and a boron (B)-toxicity treatment was induced by increasing B 10-fold in the complete nutrient formula. Plants were monitored daily to document sequential series of symptoms as they developed. Typical symptomology of nutrient disorders and corresponding tissue concentrations were determined. All treatments exhibited deficiency symptomology. Disorders for nitrogen (N), iron (Fe), calcium (Ca), and sulfur (S) were the first to manifest in pinks. Unique symptomology was observed for plants grown under potassium- (K), B-, copper- (Cu), and molybdenum- (Mo) deficient conditions, which supported the need for a species-specific approach when characterizing nutrient disorders of floriculture crops. 相似文献
97.
Abhishek Kumar Asit Das Singray Saleeb Kullu Sharad Moreshwar Durge Anil Kumar Sharma 《Journal of animal physiology and animal nutrition》2021,105(2):406-417
This experiment was conducted to study nutrient and mineral utilization in greater one-horned rhinoceros fed season-specific diets. Nine adult greater one-horned rhinoceros (774–2407 kg BW) of Sanjay Gandhi Biological Park, Patna, Bihar, India, were used in this experiment. Three digestion trials of 60-d duration were conducted per animal, out of which 55 days was adaptation period and 5 days was collection period. The amount of concentrate was kept constant during all the trials. Green fodder sources were sugarcane, berseem (Trifolium alexndrinum) and chari (Sorghum bicolor) during trials I, II and III respectively. Green fodders were offered 20% in excess of previous day's intake in the afternoon. Apparent digestibility of dry matter and crude fibre was higher (p < .01) in group II as compared to other groups. Apparent digestibility of crude protein was lowest (p < .01) in group I, followed by group III, and the highest value was observed in group II. Apparent digestibility of Ca and P was lower in greater one-horned rhinoceros fed sugarcane and sorghum as green fodder source. In spite of this, sugarcane and sorghum-based diets were able to meet the requirement of Ca, P, Fe and Mn. Berseem supplied Ca in excess of requirement. All the diets were deficient in Zn. Hence, a suitable supplement of Zn should be added to the conventional zoo diet of greater one-horned rhinoceros. 相似文献
98.
99.
ABSTRACT Greenhouse experiments were conducted to assess the effects of salinization of soil on emergence, seedling growth, and mineral accumulation of Prosopis cineraria (Linn.) Druce (Mimosaceae). A mixture of chlorides and sulfates of sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg) was added to the soil and salinity was maintained at 5.1, 7.2, 9.3, 11.5, and 13.3 dS m?1. A negative relationship between seedling emergence and salt concentration was obtained. Seedlings did not emerge when soil salinity exceeded 11.5 dS m?1. Results suggested that this tree species is salt tolerant at seed germination and seedling stages. Elongation of stem and root was retarded by increasing salt stress. Young roots and stem were most tolerant to salt stress, followed by old roots and leaves. Leaf tissue exhibited maximum reduction in dry-mass production in response to increasing salt stress. However, production of young roots and death of old roots were found to be continuous and plants apparently use this process as an avoidance mechanism to remove excess ions and delay onset of ion accumulation in this tissue. Plants accumulated Na in roots and were able to regulate transfer of Na ions to leaves. Stem tissues were a barrier for translocation of Na from root to leaf. Moreover, K decreased in root tissues with increased salinization. Nitrogen (N) content significantly (P < 0.01) decreased in all tissues (leaf, stem, and root) in response to low water treatment and salinization of soil. Phosphorus (P) content significantly (P < 0.01) decreased while Ca increased in leaves as soil salinity increased. Changes in elements-accumulation patterns and the possible mechanisms for avoidance of Na toxicity in tissues and organism level are discussed. 相似文献
100.
L. Custódio P. J. Correia M. A. Martins-Loução A. Romano 《Journal of plant nutrition》2013,36(5):739-753
The mineral concentration of flowers and the seasonal fluctuation of macro- [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] and micronutrients [iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu)] in leaves of male, female, and hermaphroditic carob trees (Ceratonia siliqua L.) were studied. The nutrient dynamics were linked not only to phenological events, but also to the gender of the trees. The females were able to allocate more nutrients to leaves than male trees, even though male flowers were richer in particular elements such as N and Zn. The hermaphrodites supported the development of both inflorescences and fruits with a lower seasonal variation and a lower leaf nutrient concentration, as compared to the other genders, which may indicate a more efficient use of resources. Flowers had, in general, a higher concentration of N, P, and K, and a lower Mn concentration than in leaves. Flowers of the females had a lower nutrient concentration compared to males or hermaphrodites. 相似文献