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841.
氮锌配施对不同冬小麦品种产量及锌营养的影响   总被引:13,自引:2,他引:11  
为比较石灰性土壤氮锌配施对不同小麦品种生长及锌营养的影响,选10种本地主要种植小麦品种,进行连续两年的田间试验,测定小麦产量及锌含量。结果表明,在石灰性土壤上单施锌肥和氮锌配施对小麦产量、籽粒锌含量的影响因品种而异。单施锌肥及氮锌配施处理可显著增加土壤有效锌含量,但单施锌肥处理仅增加"西杂1号"、"武农148"、"郑麦9023"籽粒锌含量;氮锌配施增加除"小偃22"外其余9种供试小麦品种籽粒锌含量,增幅为7.3%~54.7%。单施锌肥对小麦锌累积量增加的效果不明显;氮锌配施可显著增加小麦地上部锌累积量,两季分别增加6.5%、29.8%。单施氮肥可显著增加小麦锌吸收,但其主要累积在小麦茎叶部。在石灰性土壤上,单施锌肥虽显著增加了土壤有效锌含量,但对小麦产量及籽粒Zn含量增加有限,氮锌肥配施可取得较好效果。  相似文献   
842.
Widespread Zn deficiency for rice crop has been reported from different parts of the world, including India. To correct such deficiency, Zn is often applied to the soil as fertilizer. Its concentration in soil solution and its availability to crops is controlled by sorption?–?desorption reactions at the surfaces of soil colloidal materials. The objective of this study was to compare the availability and relative effectiveness of Zn from Zn-EDTA and ZnSO4 sources by applying different Zn levels to a calcareous soil in field experiments through soil application. The uses of Zn-EDTA also increase the yield of rice dry matter yield and grain yield. Regarding maintenance of Zn in soil, it has been observed that the amount of Zn content was recorded higher with the split application of Zn-EDTA as compared to ZnSO4 with the simultaneous 26.1% increase in the yield of rice.  相似文献   
843.
Abstract

Foliar fertilization with micronutrients and amino acids (AAs) has been used to increase the grain yield and quality of different crops. The aim of the present study was to evaluate the effects of Zn and AAs foliar application on physiological parameters, nutritional status, yield components and grain yield of wheat-soybean intercropping under a no-till management. We used a randomized block experimental design consisting of eight treatments and four replicates. The treatments were five Zn rates (0, 1, 2, 4 and 8?kg ha?1) and 2?L ha?1 of AAs and three additional treatments: a control (without the Zn or AA application), 2?kg ha?1 Zn and 2?kg ha?1 Zn + 1?L AA. The treatments were applied by spraying during the final elongation stage and at the beginning of pre-earing for the wheat and in growth stage V6 for the soybean for two crop years in a Typic Oxisol (860?g kg?1 clay). Zinc foliar fertilization increased the wheat grain Zn concentrations. The Zn rates and AA foliar fertilization in soil with did not affect the physiological parameters, nutrient status or yield components. The AA application at the different concentrations tested changed the soybean grain yield and the leaf N concentration. The results suggest that Zn and amino acids application increases the grains Zn concentration in the wheat, being an important strategy to agronomic biofortification.  相似文献   
844.
Zinc deficiency was induced in two sorghum hybrids and their parent cultivars by growing them in complete nutrient medium for 30 days and then transferring to minus zinc medium at pH 6.4. The onset of Zn chlorosis and recovery as well as the change in the pH of the nutrient medium under Zn‐stress conditions were recorded. It was found that chlorotic symptoms due to Zn deficiency appeared after 2 days of stress and persisted for a long period in the cultivars, 36‐A and 168, while the hybrid CSH‐7 (36‐A X 168) recovered from chlorosis after 12 days. The hybrid CSH‐8 (36‐A X PD‐3) was chlorotic after 2 days, but recovered after 15 days.

A significant hybrid vigor was observed for Zn‐stress tolerance in the hybrid CSH‐7 and CSH‐8.  相似文献   

845.
Zinc absorption and transport patterns were examined in sorghum and maize hybrids and their parent cultivars with a view to observe, if any, and relate the differences amongst them meaningfully to traits like hybrid vigor. Short term uptake by excised roots or intact seedlings, from different concentrations of ZnCl2 or ZnEDDHA and also, time course from 50 μM ZnCl2, were measured. The results showed significant differences in the Zn absorption patterns by excised roots of sorghum cultivars. The rate of Zn transport to shoot in CSH‐8 was found to be higher than in others. The amount of Zn transported from ZnEDDHA was also more than that from ZnCl2 in all sorghum cultivars. Furthermore, significant hybrid vigor was observed in Zn transport from ZnEDDHA for the two hybrids CSH‐7 and CSH‐8. The resemblance of absorption and transport patterns of Zn in CSH‐8 to those of 36‐A strongly suggests that the trait is inherited from the female parent.

No heterosis was observed in the absorption and transport of Zn in maize hybrids. However, a linear and an exponential isotherms for Zn transport in Ganga‐5 and Ganga‐2 hybrids indicates some hybrid vigor.  相似文献   

846.
Two experiments were undertaken to determine the effect of mycorrhizal inoculation and soil solution phosphorus (P) concentration on the growth of pejibaye (Bactris gasipaes, Palmae) seedling progenies from two Amazonian populations in a Hawaiian Oxisol. Mycorrhizal colonization and effectiveness were insignificant, perhaps because of residual fumigant toxicity and apparent water stress. Soil solution P concentration had highly significant effects on seedling leaf number, leaf area, plant biomass, anthracnose damage to leaves, and growth and physiological parameters in both experiments. Genotype effects were significant in the experiment involving progenies from two different populations, but not in the experiment involving two progenies from the same population. Native soil solution P concentration in this Oxisol was insufficient for acceptable pejibaye growth, while 0.2 mg/L soil P gave very good growth.  相似文献   
847.
Improving uptake, translocation, and utilization of foliar applied Fe and Zn is essential for increasing biomass and grain yield under deficient conditions. We compared the effect of foliar applied lipid-based Pheroid Fe- or Zn- nanoformulation, chelate and sulfate forms on biomass, nutrient uptake and mobilization in maize grown under Fe and Zn deficiency scenarios in hydroponic systems and field trials. Foliar spray of Fe-Pheroid nanoformulation resulted in complete re-greening. Partial and no re-greening of mature and young leaves, respectively, were observed under FeSO4 and Fe-HEDTA treatments. Foliar spray of Zn-Pheroid nanoformulation increased the Zn concentration of young leaves. In field trials, foliar spray of Fe- or Zn- chelate did not improve leaf Fe and Zn concentration or grain yield. Fe- and Zn-Pheroid nanoformulation improved the mobility of Fe and Zn within the plant. Field trials indicated that non-lipid-based formulation was not effective in amelioration of Fe- and Zn deficiency.  相似文献   
848.
ABSTRACT

A greenhouse experiment with four bread wheat [Triticum aestivum L.] genotypes, ‘Rushan,’ ‘Kavir,’ ‘Cross,’ and ‘Falat,’ and a durum wheat [Triticum durum L.] genotype, ‘Dur-3,’ at two zinc (Zn) rates (0 and 15 mg Zn kg?1 dry soil) and four salinity levels (0, 60, 120, and 180 mM NaCl) was conducted. After 45 d of growth, the shoots were harvested, and Zn, iron (Fe), potassium (K), sodium (Na), and cadmium (Cd) concentrations were determined. In the absence of added Zn, visual Zn deficiency symptoms were observed to be more severe in ‘Dur-3’ and ‘Kavir’ than in other genotypes. The effect of Zn deficiency on shoot dry matter was similar to its effect on visual deficiency symptoms, such that shoot growth was most depressed in ‘Kavir’ and ‘Dur-3.’ At the 180 mM treatment, Zn fertilization had no effect on shoot dry matter of genotypes. Genotypes with high Zn efficiency had greater shoot Zn content than genotypes with low Zn efficiency. In the absence of added Zn, the Dur-3, and ‘Cross’ genotypes had the highest and lowest Cd concentrations, respectively. Application of Zn had a positive effect on salt tolerance of plants.  相似文献   
849.
The interactions of zinc (Zn) and cadmium (Cd) in uptake and translocation are common but not consistent. We hypothesized that Cd2+ and Zn2+ activity in the apoplasmic solution bathing root-cells could affect Zn accumulation in plants dependent on the wheat genotype. This hypothesis was tested using seedlings of two bread wheat genotypes (Triticum aestivum L. cvs. Rushan and Cross) and one durum wheat genotype (Triticum durum L. cv. Arya) with different Zn efficiencies grown in chelate-buffered nutrient solutions with three Zn2+ (10?11.11, 10?9.11, and 10?8.81?µM) and two Cd2+ (10?11.21 and 10?10.2?µM) activity levels. Increasing Zn2+ activity in the nutrient solution significantly increased Zn concentration in root and shoots of all three wheat genotypes, although the magnitude of this increase was dependent on the genotype. Cadmium decreased Zn concentration in roots of “Cross” while it had no significant effect on root Zn concentration in “Rushan.” At Zn2+?=?10?11.11?µM, Cd decreased shoot Zn concentration in “Arya” whereas it increased shoot Zn concentration at Zn2+?=?10?8.81?µM. Cadmium increased shoot Zn concentration of “Rushan” and “Cross” at Zn2+?=?10?8.81?µM but it had no significant effect on shoot Zn concentration of these genotypes at Zn2+?=?10?11.11?µM. The zinc-inefficient genotype “Arya” accumulated significantly more Cd in its root in comparison with “Cross” and “Rushan.” Cadmium concentration in roots of “Arya” was decreased significantly with increasing Zn activity. The effect of Zn on accumulation of Cd in roots of “Cross” and “Rushan” was dependent on the dose provided, and therefore, both synergistic (at Zn2+?=?10?9.11?µM) and antagonistic (at Zn2+?=?10?8.81?µM) interactive effects were found in these genotypes. Zinc supply increased the Zn concentration of xylem sap in “Cross” and “Rushan” whereas Zn content in xylem sap of “Arya” was decreased at Zn2+?=?10?9.11?µM and thereafter increased at Zn2+?=?10?8.81?µM. Cadmium treatment reduced Zn concentration in xylem sap of “Arya,” while it tended to increase Zn content in xylem sap of “Cross.” At Zn-deficient conditions, greater retention of Zn in root cell walls of Zn-inefficient “Arya” resulted in lower root-to-shoot transport of Zn in this genotype. Results revealed that the effect of Cd on the root-to-shoot translocation of Zn via the xylem is dependent on wheat genotype and Zn activity in the nutrient solution.  相似文献   
850.
Micronutrient malnutrition, especially zinc (Zn) and iron (Fe) deficiency in diets, has aroused worldwide attention. Biofortification of food crops has been considered as a promising approach for alleviating this deficiency. Quantitative trait locus (QTL) analysis was performed to dissect the genetic mechanism of Zn and Fe content in maize grains using a total of 218 F2:3 families derived from a cross between inbred lines 178 and P53. Meta-analysis was used to integrate genetic maps and detect Meta-QTL (MQTL) across several independent QTL researches for traits related to Zn or Fe content. Five significant QTLs and 10 MQTLs were detected. Two informative genomic regions, bins 2.07 and 2.08, showed a great importance for Zn and Fe content QTLs. The correlation between Zn and Fe level in maize grains was proposed by MQTLs as 8 of the 10 involved both traits. The results of this study suggest that QTL mapping and meta-analysis is an effective approach to understand the genetic basis of Zn and Fe accumulation in maize grains.  相似文献   
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