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1.
A significant reduction in the growth parameters viz., plant height, number of tillers, number of productive tillers, leaves, leaf area, 1000 grain weight and grain yield were observed in the mottle streak virus infected finger millet plants compared to healthy finger millet plants. The germination and vigour of seedlings from the seeds of infected plants were reduced. Physiological changes in finger millet as a result of virus infection were investigated. The chlorophyll pigments ‘a’ and ‘b’ as well as total chlorophyll were reduced due to mottle streak infection. The virus infection led to increased total sugar, starch, soluble protein and phenol contents. The mineral metabolism of infected plants showed a reduction in nitrogen, phosphorus, potassium, magnesium, calcium and iron.  相似文献   

2.
Summary Decreases in the concentrations of nitrogen, phosphorus, potassium, calcium and magnesium, in the shoots of wheat seedlings soon after the start of waterlogging were mainly attributed to an inhibition of ion uptake and transport by roots in the oxygen deficient soil. There was a small net accumulation of nitrogen, phosphorus and potassium by the aerial tissues, principally the tillers rather than the main shoot. By contrast, calcium and magnesium accumulated in both tillers and main shoot. With waterlogging, nitrogen, phosphorus and potassium were translocated from the older leaves to the younger growing leaves, and in the case of nitrogen this was associated with the onset of premature senescence. Calcium and magnesium were not translocated from the older leaves, the younger leaves acquiring these cations from the waterlogged soil. The promotion of leaf senescence by waterlogging was counteracted by applications of nitrate or ammonium to the soil surface, or by spraying the shoots with solutions of urea, but the beneficial effects on shoot growth were small.The role of mineral nutrition in relation to waterlogging damage to young cereal plants is discussed.  相似文献   

3.
本研究通过分析开花期灌水对小麦产量、植株养分分配和土壤养分分布的影响及其与根系特性的关系,为小麦充分利用水肥资源提供理论支撑。以抗旱高产品种‘洛麦28'和高光效品种‘百农207'为材料,采用2 m深土柱栽培方法,设置开花期灌水(T1)和开花期不灌水(T2)两个水分处理,测定了不同组织器官、不同土层土壤氮、磷、钾含量及根系分布特性等指标。结果表明: 小麦收获期土壤中铵态氮、速效磷和速效钾主要分布在0~80 cm土层中,硝态氮主要分布在80 cm以下土层中,开花期灌水促进小麦吸收0~60 cm土层的铵态氮、速效磷、速效钾和80 cm以下土层的硝态氮,减少了硝态氮向深层土壤的淋溶;小麦根系主要集中在0~60 cm土层中,随土壤深度的增加而减少。成熟期干物质积累量、全氮和全磷主要分配在小麦籽粒中,而全钾主要分配在茎秆中;开花期灌水显著增加了小麦百粒重,提高了小麦产量;根系形态指标与土壤硝态氮在0~40 cm土层中呈显著负相关,与土壤铵态氮在80~100 cm土层中呈极显著正相关,与土壤速效磷在0~100 cm土层中呈显著正相关。开花期灌水促进了根系在小麦生育末期对土壤养分的充分吸收,延长了养分从营养器官向生殖器官的转运功能期,使营养器官中的养分充分地转运到籽粒中去,增加小麦粒重,进而提高产量。  相似文献   

4.
Summary This paper describes a factorial experiment which was designed to elucidate the effect of total iron supply and rate of iron supply on the yield of tomato plants. Information was also obtained on the effect of iron supply and leaf age on the concentration of a number of nutrient elements in the leaf tissue.Increasing the total iron supply increases the yield, and the iron concentration in the leaves, while the manganese, phosphorus, sodium, calcium and magnesium decrease in concentration. The young leaves have a lower concentration of iron, manganese, potassium, sodium, calcium and magnesium than the older leaves, while the reverse is true of nitrogen and phosphorus. A slow rate of iron supply decreases the yield and sodium concentration in the leaves but increases the manganese and phosphorus concentrations.Interaction between total iron supply and leaf position affects the manganese, potassium, calcium and magnesium concentrations in the leaves, while the interaction between total-iron level and rate of iron supply affects the phosphorus and calcium concentration in the leaves.  相似文献   

5.
Summary The effect of gamma isomer of benzene hexachloride and Telodrin both in absence and presence of ammonium and nitrate nitrogen carriers on shoot and root growth and carboydrate and nitrogen constituents of sugarcane was studied. The pesticides induced shoot emergence and development of tillers and roots. Shoot growth, nitrogen intake and insoluble nitrogen content invariably increased by pesticide application while soluble carbohydrate and soluble nitrogen content of the shoot decreased. Pesticides also increased the water-soluble nitrate content of the soil.The effect of pesticides was not confined to ammonical source of nitrogen rather the pesticides proved equally effective under nitrate source of nitrogen and also in absence of additional nitrogen. Beneficial effect of pesticides on growth and development of sugarcane appears largely on account of more efficient utilisation of soil and fertilizer nitrogen. The results raise an interesting possibility of using these pesticides as growth stimulators to increase the efficiency of sugarcane plants growing under sub-optimal conditions of nitrogen  相似文献   

6.
氮磷肥配施对苦荞根系生理生态及产量的影响   总被引:2,自引:0,他引:2  
以苦荞品种‘迪庆’为材料,在盆栽试验条件下,研究了氮(纯氮用量分别为0g/kg、0.1g/kg、0.2g/kg)、磷(P2O5用量分别为0.1g/kg和0.2g/kg)配施对苦荞根系生长、生理指标及其产量的影响,旨在为黄土高原苦荞高产优质栽培提供理论依据。结果表明:(1)在相同施磷量条件下,苦荞幼苗的株高、茎粗、茎叶干重、主根长、根表面积、根系体积、根系直径、根系干重以及壮苗指数等均随施氮量的增加而呈先升后降的趋势,但根冠比随施氮量的增加而呈先降后升的趋势;叶片叶绿素含量以及根系活力、酸性磷酸酶(Apase)活性、可溶性蛋白含量和植株氮积累量随施氮量的增加呈抛物线变化趋势,根系硝酸还原酶(NR)活性和植株氮含量随施氮量的增加而增加;而根系可溶性糖含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、丙二醛(MDA)含量和游离脯氨酸含量等指标均随施氮量的增加而呈先降后升的趋势,0.1g/kg施氮处理各指标均显著低于其他处理;成熟期单株粒重、百粒重随施氮量的增加呈先升后降的趋势,0.1g/kg施氮处理各指标均显著高于其他处理。(2)在相同施氮量条件下,随着施磷量的增加,苦荞根系酸性磷酸酶(Apase)活性、SOD活性、POD活性、MDA含量、可溶性糖含量、可溶性蛋白以及游离脯氨酸含量等指标均降低,其余各指标则呈增加趋势。(3)无论施磷量条件如何,0.1g/kg的施氮处理下苦荞产量最高,与其他施氮处理相比,在低磷和高磷处理下的增产幅度分别为7.04%~37.40%和14.73%~68.26%;在施氮量一定的情况下,高磷处理比低磷处理增产15.96%~42.00%。(4)在该试验条件下,适当的氮磷肥配施表现出了明显的正加和效应,但过量施肥也有可能导致增产幅度下降,中氮高磷(施纯N量0.1g/kg,施P2O5量0.2g/kg)配施效果最优。  相似文献   

7.
Summary An application of sulphur (upto 90 ppm) alone or in combination with phosphorus and nitrogen, increased the content of total nitrogen, protein nitrogen and total soluble nitrogen but decreased amide, amino, ammoniacal and nitrate nitrogen and with further increase in dose, all the nitrogen fractions decreased. Higher doses of nitrogen in combination with sulphur increased the content of amide nitrogen and nitrate nitrogen in leaves only at 15 and 30 days stages. Higher doses of phosphorus in combination with sulphur and nitrogen decreased the content of all nitrogen fractions in leaves. All the nitrogen fractions decreased in age except the amide and ammoniacal nitrogen which increased upto 30 days and then started decreasing.  相似文献   

8.
江西省茶园土壤肥力特征及其影响因子   总被引:4,自引:0,他引:4  
为探明江西省典型茶园土壤养分状况和肥力特征,选取江西省21个地区372个典型茶园,分析茶园土壤养分的差异性、空间性、相关性及与地形、土壤类型、海拔和建园时间的关联性。结果表明: 江西省茶园土壤pH、有机质、碱解氮、速效磷、速效钾、全氮、全磷和全钾分别达到优质高效高产茶园土壤营养指标的53.9%、60.1%、56.1%、22.9%、38.5%、43.7%、11.1%和95.5%,其中速效磷为强变异;有效铜、锌、铁、锰和硼达到土壤微量元素含量分级一级标准的占比分别为76.3%、74.2%、96.8%、73.1%和0.0%。江西茶园土壤养分以赣中地区最高,其次是赣东北和赣西北地区,赣南地区最低。除全钾外,土壤pH与有机质、碱解氮、速效磷、速效钾、全氮和全磷均呈显著正相关。不同地形土壤养分以平地最高,高山次之,山地和丘陵最低;不同土壤类型土壤养分以水稻土、砂壤和山地黄棕壤较高,其次是黄壤、红黄壤和紫色土,红壤最低;土壤pH、有机质和全钾随海拔上升而递增,而速效磷随海拔上升而递减;土壤有机质、碱解氮、全氮、速效磷和全磷随建园时间的增加而递增,而土壤pH随建园时间的增加而递减。综上,江西省茶园土壤肥力总体水平良好,有机质、全钾、有效铜、锌、铁和锰均较丰富,但土壤偏酸,速效磷和全磷偏低,有效硼严重缺乏。赣中应提高土壤pH和钾肥,赣东北增加钾和氮肥,赣西北增加有机质和磷肥,赣南应增加氮磷钾肥并配施有机肥;高山茶园补充速效磷和钾肥,山地茶园提高氮和磷肥;红黄壤茶园提高土壤pH和全钾,红壤茶园应提高氮磷钾肥并配施有机肥,黄壤和山地黄棕壤茶园需要增施磷肥,紫色土茶园需提高土壤有机质;茶园需要逐年增加白云石粉、生理碱性肥料和有机肥等,防治茶园土壤酸化。  相似文献   

9.
Summary Buckwheat was grown in media in which the supply of nitrate and potassium was varied. The relation between nitrate assimilation and the carboxylate content of the plant was examined.In full supply of nitrate total carboxylate came from and was equivalent to the assimilated nitrate. Only when this nutrient was depleted, bicarbonate was absorbed and assimilated as the alternative source which caused carboxylate to accumulate in excess of the deficient level of organic nitrogen.Shortage of potassium had no effect on the level of carboxylate because increased uptake of calcium and magnesium replaced the missing potassium.  相似文献   

10.
幼龄枇杷园套种科杂1号大豆的效应   总被引:2,自引:0,他引:2  
幼龄枇杷园套种科杂1号,显著提高土壤肥力,土壤速效P由清耕对照的痕迹增至18.27 mg/kg,全P和速效K分别增加260.0%和183.6%,有机质、全N、全K和速效N的增幅在40%左右;研究还表明,套种提高了枇杷树体营养和促进丰产树冠的形成,叶片N、P、K、Ca、Mg含量均比对照区增加9%以上,冠幅和枝梢数分别增加27.3%和57.7%,枝梢抽穗率提高86.8%,同时,套种对改善果实品质也有一定作用。  相似文献   

11.
蚓粪和益生菌互作对土壤性状及番茄产量和品质的影响   总被引:1,自引:1,他引:0  
本试验研究了两株益生细菌(巨大芽孢杆菌BM和解淀粉芽孢杆菌BA)与化肥和蚓粪配施对土壤性状、番茄产量和品质的影响.结果表明:与化肥相比,在等养分条件下蚓粪能够提高番茄产量、果实可溶性糖和蛋白质含量,并提高土壤pH和速效磷含量.与单施蚓粪相比,益生菌与蚓粪配施不仅能提高番茄产量、果实可溶性糖、蛋白质、维生素C含量和糖酸比,降低有机酸和硝态氮含量,而且增加了土壤pH和硝态氮含量,降低了土壤电导率;益生菌与化肥配施的效果不如益生菌与蚓粪配施.BA和BM与化肥或蚓粪配施时,番茄品质无显著差异,但BA配施蚓粪处理的番茄产量显著高于BM配施蚓粪处理;BM与化肥配施处理显著提高了土壤速效磷含量,而BA与蚓粪配施处理则显著提高了土壤速效钾含量.本研究表明,益生菌和蚓粪可替代化肥用于番茄生产和土壤肥力改良.  相似文献   

12.
The uptake of nitrogen and its distribution between shoots and between organs within shoots in wheat (Triticum aestivum) was studied from the start of stem elongation to 28 days after anthesis in a glasshouse experiment with eight nitrogen levels between 0·1 and 12·8 mequiv./litre. There was no net uptake of nitrogen in plants supplied with 0·8 mequiv./litre or less; with more nitrogen the absorption increased linearly. Twenty to 44% of the total plant nitrogen was absorbed after anthesis, this fraction increasing with nutrient supply. The nitrogen allotted to the main shoot decreased until the onset of anthesis and increased thereafter at the expense of the tillers, except with 12·8 mequiv./litre, where nitrogen percentage in the main shoot decreased also after anthesis. Raising nitrogen supply increased the proportion of plant nitrogen recovered in the tillers. Nitrogen accumulated in the ear after emergence and by the 28th day after anthesis it contained between 52% and 73% of the total plant nitrogen. The ear of the main shoot had a higher proportion of shoot nitrogen than that of the tillers. The fraction of ear nitrogen supplied by retranslocation decreased from almost 100% with 0·8 mequiv. N/litre or less to nil with 12·8 mequiv./litre. Increasing nitrogen application decreased the fraction of total nitrogen allocated to the ear.  相似文献   

13.
Two cultivars of spring wheat (Triticum aestivum L.) were grown to maturity in hydroponic cultures. Nitrogen accumulation was controlled by daily growth-limiting additions of nitrate together with all other nutrients in excess. Six different curves of N accumulation were used, with the same relative changes from day to day, but with different amplitudes. These curves were obtained by using the same mathematic formula of the N accumulation curves but varying the value of initial N content. The total amount of nitrogen added varied from 20 mg plant(-1) to 65 mg plant(-1). Plant bioproductivity showed a linear response to accumulated N. The number of grains per plant increased linearly with increased N availability whereas grain weights were essentially unaffected. Grain N concentrations and N content varied slightly, with highest values generally at the lower N availability levels. The quantitatively most important response to increased N availability was an increased number of earbearing tillers per plant. This varied from 0.1 tiller plant(-1) at maturity when given 20 mg N plant(-1), up to about 2 tillers plant(-1) when given 65 mg N plant(-1). Not all tillers that were initiated developed ears. The reduction of tillers seems to be one important mechanism in adapting plant productivity to N availability. Other individual characters influenced by N availability were straw height and the number of spikelets per spike. The two cultivars behaved in a qualitatively similar manner over the range of N availability even though they quantitatively differed in grain size, N concentrations and yield.  相似文献   

14.
为了改善坡地苹果园的土壤环境,遏制水土流失和土壤养分流失,探寻聚丙烯酰胺适宜的干撒施用量,2010—2012年在陕北丘陵沟壑区的坡地苹果园,以不施聚丙烯酰胺为对照,分别撒施0.6、0.8、1.0、1.2、1.4和1.6 g·m-2的聚丙烯酰胺,监测果园地表产流、土壤流失、养分流失和苹果植株生长状况.结果表明: 坡地果园的径流量和5—7月的产流次数均随聚丙烯酰胺撒施量的增加呈“V”型变化,其中撒施量为1.0 g·m-2时最低,但果园侵蚀泥沙量则随聚丙烯酰胺撒施量的增加而降低.地表径流和侵蚀泥沙中的铵态氮、速效磷和速效钾的浓度均随聚丙烯酰胺撒施量的增加而降低;聚丙烯酰胺可显著降低地表径流中的硝态氮含量,对侵蚀泥沙中的硝态氮含量则无显著影响;侵蚀泥沙中的有机质、全氮、全磷和全钾含量均随聚丙烯酰胺撒施量的增加而降低.聚丙烯酰胺提高了苹果单果质量及产量,但对苹果植株生长及果实风味品质无显著影响.聚丙烯酰胺在坡地苹果园中的适宜撒施量应为1.0 g·m-2.  相似文献   

15.
The influence of irrigation on yield response of tea to NPK fertilizers and the importance of the nitrogen source for yield response to nitrogen were investigated in two locations of northern Iran. There was a large difference between locations in green leaf yield due to differences in rate of precipitation. In both locations, irrigation at the rate of 420 mm during the 6-month growing period was more effective in increasing both yield and yield response to nitrogen, phosphorus and potassium than the most favourable rate of fertilizer. With a total water supply of up to 770 mm, tea showed a moderate response to nitrogen and phosphorus but no or low response to potassium, while with 1100 mm of water a considerably high response to each nutrient and their combinations was observed. Ammonium sulphate produced 15–20% more yield than corresponding urea treatment. Addition of sulphur together with urea reduced the differences. This work was supported by the Scientific Research Council of the University of Teheran, Teheran, Iran  相似文献   

16.
采用二次通用旋转组合设计 ,在辽西半干旱区褐土上进行了长期田间试验 ,研究不同的灌水、施氮、施磷和施秸秆水平对土壤钾含量的影响。结果表明 ,土壤全钾含量随着氮、磷和秸秆施用量的增加而增加 ,随着灌水量的增加而降低 ,其中 ,施磷对土壤全钾含量的增加效果最明显 ,其次是施秸秆量。土壤速效钾含量随着灌水和氮、磷施用量的增加而降低 ,随着秸秆施用量的增加而增加 ,其中 ,施秸秆对土壤的速效钾含量影响最明显 ,其次是施用磷肥的影响。另外 ,施肥和灌水在提高土壤全钾含量的同时可能使速效钾含量降低 ,两者的变化表现为一定的负相关。  相似文献   

17.
Absorption of nitrogen, phosphorus and potassium by S48 timothy plants ran parallel to dry-weight increase, at an increasing rate until the autumn, almost completely ceasing in the winter, and increasing again in the spring.
Flowering tillers accumulated nutrients until ear emergence, after which the content per tiller of all nutrients decreased until death of the tillers during the winter.
Non-flowering tillers continued to accumulate nutrients steadily throughout the whole period of the experiment.
These observations are discussed in relation to the perennial habit of the plant.  相似文献   

18.
Summary The influence of nitrogen, phosphorus, and potassium on the reduction processes in the rhizosphere of rice grown in solution culture and of rice under lowland conditions was studied. In solution culture the redox potential in the complete nutrient solution was highest, indicating that fully nourished roots have the highest oxidizing power. When the supply of only one element was interrupted, the lack of potassium in the nutrient solution caused the greatest decline in redox potential. Redox potential was further decreased when, besides nitrogen, either phosphorus or potassium was discontinued. Simultaneous deficiencies of nitrogen and potassium lowered redox potential even more severely than did deficiency of all three elements. A long-term nitrogen fertilizer trial under lowland conditions, however, revealed that an abundant supply of nitrogen can decrease redox potential. Redox potential was higher in the soil near plants than in the soil away from plants. In solution culture, at low Eh levels, the increase in iron reducing power of the solution was correlated with the decrease in redox potential. The total number of bacteria and iron reducing bacteria increased almost parallel to the decrease in redox potential and increase in iron reducing power. These relationships show that the nutritional status of the rice plant essentially influences bacterial activity and, thus, oxidation-reduction conditions around the roots. Since sufficient potassium nutrition seems important in maintaining the oxidising power of rice roots, root growth in a potassium deficient soil with K application was compared with root growth without K application. Without potassium the fine lateral roots far from the root base showed black coloration due to ferrous sulfide, indicating a loss of oxidising power. With increasing potassium supply, this phenomenon disappeared and the iron content of the rice plants decreased. re]19751208  相似文献   

19.
Ammonium nitrate solution applied to the leaves of sugar-beetincreased plant dry weight and uptake of nitrogen by the roots.Uptake of phosphorus by the roots of swedes, but not sugar-beet,grown with high phosphorus supply to the roots, was decreasedby applying sodium phosphate solution to the leaves; uptakefrom a lower phosphorus supply to the roots was unaffected.Phosphorus applied to the leaves had no effect on dry weight.Potassium uptake by the roots of sugar-beet plants grown withhigh potassium supply to the roots was unaffected by paintingthe leaves with a potassium chloride solution, that of plantswith an intermediate potassium supply was increased, and plantsgrown with a low supply to the roots absorbed almost all theavailable potassium so painting could not much increase uptakeby the roots. Application of potassium to the leaves increaseddry weight of plants with low or medium potassium supply tothe roots and did not affect that of plants with a high potassiumsupply. The top: root ratio for phosphorus content in mg. per plantwas greater for phosphorus absorbed via leaves than for phosphorusabsorbed via roots. Increasing the phosphorus supply to theroots increased this ratio for phosphorus absorbed either vialeaves or roots. Potassium absorbed by leaves was slightly more efficient inincreasing dry weight than potassium absorbed at the same timeby the root. A similar comparison was not possible for nitrogenor phosphorus. The results of these and previous experiments indicate thatall the nitrogen and potassium and over 80 per cent. of thephosphorus applied to leaves was absorbed. The small amountof phosphorus remaining unabsorbed on the surface of the leafwas unaffected by phosphorus supply to the root.  相似文献   

20.
The aim of this work is to show and give a plausible explanation to gender-dependent differences in correlations between the content of selected elements in rainwater and the frequency of hospitalization by reason of arterial hypertension, chronic obstructive pulmonary disease (COPD), and psoriasis in the area of Opolskie Voivodeship, Poland, during the period 2000-2002. The elements analyzed were sodium, potassium, calcium, magnesium, manganese, iron, total phosphorus, total nitrogen, ammonium nitrogen, zinc, copper, lead, cadmium, nickel, chromium, chloride, nitrate, and sulfate. Hospitalization due to arterial hypertension was more frequent in women, whereas those for COPD and psoriasis were more frequent in men. In the case of women hospitalized for arterial hypertension, the correlations were low, except for zinc (r = 0.47) and for cadmium (r = 0.43). In men hospitalized for COPD, all of the correlation coefficients were higher than 0.4, except for phosphorus. The coefficients for nickel, ammonia nitrogen, and total nitrogen ranged from 0.5 to 0.6 and the remaining elements from 0.6 to 0.7. In women, the correlation was limited to five elements where the coefficient was r > 0.4 for chloride, calcium, nitrate, phosphorus, and chromium. In cases of hospitalization for psoriasis, the correlation in men was between 0.4 and 0.5 for chloride, phosphorus, copper, lead, and total nitrogen and greater than 5 for sulfate, potassium, calcium, iron, manganese, nitrate, and ammonium nitrogen. The correlation in women was between 0.48 and 0.5 for ammonium nitrogen and phosphorus.  相似文献   

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