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1.
Abstract

Microbial metabolism in reduction process of waterlogged paddy soils has been studied by Takai, Koyama, and Kamura (1, 2, 3, 4, 5, 6), Koyama (7, 8, 9, 10, 11, 12), and others. The results indicated that microbial metabolism in waterlogged soils takes place according to the following steps: (1) In the early stage of the incubation period, dissolved O2, is consumed and the redox potential drops rapidly. (2) NO2? and NO2? are reduced to N2. (3) Mn4+ is reduced to Mn2+. (4) Fe3+ is reduced to Fe2+. (5) SO4 2? is reduced to S2?. (6) H2 and CH4 are produced. Takai and Chiang (13) reported that NH4+ and PO4 3+ in waterlogged paddy soils increase with the incubation period. Chiang and Takai (14) indicated that carbohydrates in the soil solutions almost remain constant throughout the incubation period, however, organic acids change similarly to those reported previously (5, 6).  相似文献   

2.
There have been several papers dealing with the difference in chemical composition between callus tissue and normal parent tissue. WEINSTEIN, TULECKE, NICKELL, and LAURENCOT (1–3) revealed, in a series of papers, that the contents of amino acids, sugars, and nucleic acids often differed strikingly between callus and normal tissue of Agave toumeyana Trel. (1), Ginkgo biloba, L. (2), and PAUL's scarlet rose (3). STEWARD, THOMPSON, and POLLARD (4) also reported that the content of some amino acids of rapidly growing and randomly proliferating tissue is outstandingly different from that of normal tissue.  相似文献   

3.
It has been well known that the glutamic acid decarboxylase occured1 and γ-aminobutylic acid was contained2 in the higher plant. In the tobacco plant, the property of this enzyme was investigated in detail by Tomita 3, and Noguchi 4 showed. the comparatively higher concentration of γ-aminobutylic acid in tobacco leaves.  相似文献   

4.
Phosphorus in soils is found to be present in organic combinations, inorganic form or in adsorted form on clay complex. Different forms of soil phosphorus have different solubilities and consequent availability in soils. A knowledge about the content and types of soil phosphorus enables one to understand the organic behaviour and predict the response of added phosphatic material to crops (Parker 1953). The form in which phosphorus is present in soil is directly related to pH and CaCO3 in the soil as well as the intensity of the development of the soil. Williams (1950) has found that in calcareous soils of South Australja most of the phosphorus was in combination with calcium, whereas in acid soils it forms compounds with alumina and iron. Hibbard (1931) concluded that in alkaline and calcareous soils, phosphorus exists mostly in the form of hydroxyapatite, chloroapatite, and the like. Kanwar and Grewal (1959) studied fractionation of phosphorus in Punjab soils and reported that differences in the nature and amounts of the phosphorus present in acid and alkaline soils of the State explain the causes of different phosphatic fertilizer responses to the crops. A similar report has been given by Goel and Agarwal (1959) who studied the fractionation of phosphorus in Kanpur soils and concluded that the mature soils are rich in iron and aluminium bound phosphorus and respond better to phosphatic fertilizer than the immature soils rich in Ca2+ and Mg2+ bound phosphorus. Chai Moo Cnoo and Caldwell (1959) reported that Fe3+ and Al3+ bound phosphorus was abundant in acid soils while Ca2+ and Mg2+ bound phosphorus content in alkaline soils, and organic phosphorus agreed, in general, with the content of organic matter, with some deviations.  相似文献   

5.
Most reports of the studies on solubilisatioh of phosphate in liquid culture and soil suggested that organic acids produced by microorganisms are responsible for promoting the dissolution of phosphate. Sperber (11, 12), Louw and Webley (7) and Duff, Webley and Scott (2) studied the production of acids by cultures of some phosphate dissolving fungi. actinomycetes and bacteria and observed that among the acids produced in liquid medium, hydroxy carboxylic acids such as lactic and 2-ketogluconic acids were responsible for solubilisation of phosphates. In the present studies, apart from the culture of Bacillus megaterium var. phosphaticum isolated from phosphobacterin which had been obtained from USSR. Indian strains of Bacillus megaterium, Bacillus circulans and Escherichia freundii isolated and identified by Sundara Rao and Sinha (13) were used. These studies were undertaken to find out different types of nonvolatile acids produced in Pikovskaya's (9) liquid medium.  相似文献   

6.
Nodule growth of a hypernodulating soybean (Glycine max (L.) Merr.) mutant line NOD1-3 was compared to that of its wild-type parent cv. Williams from 14 to 18 days after planting (DAP) in the absence of nitrate treatment (hereafter referred to as “0 mM treatment”) or with 5 mM nitrate treatment. The growth rate determined by increase in the diameter of the nodules was relatively lower in the mutant NOD1-3 than that of the parent Williams under nitrogen-free conditions (0 mM nitrate). The inhibition of nodule growth by 5 mM nitrate started at 1 d after the onset of the nitrate treatment in Williams, while the inhibition did not occur before the application of the nitrate treatment for 2 d in NOD1-3. The nodule growth was completely inhibited after 2 d in Williams and after 3 d in NOD1-3 during the 5 mM nitrate treatment period. After 4 d of 5 mM nitrate treatment, the nodule dry weight decreased by 22% in NOD1-3 and by 58% in Williams, respectively. The treatment with 5 mM nitrate decreased the acetylene reduction activity (ARA) in NOD1-3 by 60% per plant and by 50% per nodule g DW and these parameters were less sensitive to the treatment than those in Williams in which the inhibition rate was 90% per plant and 80% per nodule g DW. These results indicate that NOD1-3 is partially nitrate-tolerant in terms of individual nodule growth as well as total nodule dry weight and Nz fixation activity. A whole shoot of Williams and NOD1-3 plants was exposed to 14CO2 for 120 min followed by 0 or 5 mM nitrate treatment for 2 d, and the partitioning of the photoassimilates among the organs was analyzed. Under 0 mM nitrate treatment, the percentages of the distribution of 14C radioactivity between the nodules and roots were 63 and 37% in Williams and 89 and 11% in NOD1-3. Under the 5 mM nitrate conditions, the percentages of the distribution of 14C between the nodules and roots changed to 14 and 86% in Williams and 39 and 61% in NOD1-3, respectively. These results indicated that the hypernodulating mutant NOD1-3 supplied a larger amount of photoassimilates to the nodules than to the roots under nitrogen-free conditions, and that the nitrate depression of photoassimilate transport to the nodules was less sensitive than that of the parent line.  相似文献   

7.
A greenhouse experiment was conducted at Land Resources Research Institute, NARC, Islamabad to examine the impact of humic substances (HSs) coating on potassium fertilizers use efficiency. Tomato variety “Rio Grande” was used. The treatments applied were T1= Control (N, P at 250 and100?mg kg?1 respectively), T2?=?N, P?+?K at 200?mg kg?1 as SOP, T3?=?N, P?+?K at 200?mg kg?1 as NPK blend, T4?=?N, P?+?K at 200?mg kg?1 HSs coated SOP) and T5?=?N, P?+?K at 200?mg kg?1 HSs coated NPK blend. Results indicated a positive impact of sole and HSs coated products on agronomic traits, nutrient concentration, fruit quality traits, flower number, fruit umber, fruit weight, chlorophyll contents, fresh and dry biomass, tissue water contents, diameter and fruit mineral composition. The response of afore said traits to applied treatment varied.  相似文献   

8.
The soils of Rajasthan vary from desert sand to heavy clay with all intermediate stages like sandy loam, loam and clay loam. The last two textural groups are more prevalant on the eastern, northeastern and southeastern part of the Aravallies which run almost in the middle of the State from southeast to northeast. The latter groups of soils have more potential from the point of agricultural development in the State. These soils are widely termed as alluvial soils which is a general term to indicate the nontaxonomic group of soils that have parent material of alluvial origin, Riecken 17, Kelloog 8 has referred to the soils developed from the alluvium as classified under variety of world soil groups. In our country many of the alluvial soils have not yet been studied from the soil genesis point of view as a measure to classify the soils under taxonomic groups. Ray Chawdhary and Mukerji 15, concluded that the alluvial soil groups of our country are ill defined and the classification of these soils need more study. Basu 3 was able to distinguish the genetic characteristics of the soils of Deccan. Agrawal and Mukherji 1) established that distinct genetic soil types have come into expression under Gangetic alluvium. Agarwal 2 has concluded about the three types of soils in the toposequence with precipitated calcium throughout, zone of calcium accumulation in the bottom of the profile and soils free of calcium, and suggests that the soils of Gangetic plain be called as derived from alluvium. A process of reclassifying the alluvial soil series into taxonomic groups is a common trend in the United States since the last two decades.  相似文献   

9.
Blast disease is one of the biggest diseases of rice plant in Japan. For example, in 1953, the total area of damage by blast disease was about 160 × 104 hectare and the decreased yield of rice Was about 67.5 × 104 ton in Japan. There have been many studies on blast disease for a long time. Tanaka and Katsuki (7)studied the relation between environmental conditions and blast disease. They always used adult healthy rice plants as plant materials and have not analysed the plants damaged by blast fungus directly. They suggested the presence of growth-promoting factors of blast funngus especially in susceptible rice varieties. Tamari and Kaji (5, 6) suggested that the blast fungus produced some effective toxic substances which might cause the disease. Suzuki, Doi and Toyoda (4) continued to study the mechanism of rice blast resistance and they have proposed 3 phases of resistance. They are (a) resistance and environtmental factors, (b) resistance and host camponents and (c) relation of host variety to fungus race.  相似文献   

10.
Abstract

Studies on nutrient interactions in aromatic rice are needed for proper understanding of impact of imbalanced use of nutrients in the era of multi and micro-nutrient deficiencies. A pot experiment was conducted during the rainy/wet season (June–October) of 2013 at New Delhi, to study the interaction effects of two levels each of nitrogen (N) (0 and 120?kg?ha?1), phosphorus (P; 0 and 25.8?kg?ha?1), and zinc (Zn; 0 and 5?kg?ha?1) in two aromatic rice (Oryza sativa L.) varieties, viz. Pusa Rice Hybrid 10 and Pusa Basmati 1121. Application of N, P, and Zn resulted in increase of dry matter (0.91, 0.32, and 0.24?g plant?1, respectively) 60?days after sowing (DAS) and grain yield of rice (3.68, 1.67, and 1.17?g plant?1). The increase in yield of rice owing to N application was relatively higher by 0.98, 0.22, and 1.05?g plant?1, respectively, when either P or Zn or both were applied with N than alone application of N, indicating synergetic effect of P and Zn application with N. The higher concentration and uptake of K in grain (0.25% vs 0.10%) and straw (1.32% vs 0.94%) were observed in the treatment received N than no N, though K was applied uniformly in all the treatments. It indicates positive interaction of N and K. The higher uptake of P in grain and straw was observed when P was applied with N and Zn (3.34 and 2.15?mg plant?1), or with N (3.26 and 2.11?mg plant?1) signifying positive effect of N on P uptake in rice.  相似文献   

11.
It is well known that methyl mercaptan is porduced by the microbiological decomposition of methionine1),2),3). According to Kondo 4) and Onitake 1)not only hydrogen sulfide, but also methyl mercaptan were produced from cystine by E. coli and Proteus vulgaris in the medium containing one of glucose, lactose, sucrose, glycerin or histidine. Moreover, Onitake 1) found that methyl mercaptan was produced by the action of E. coli in the medium containing hydrogen sulfide and a trace of ethyl alcohol, and that evolution of methyl mercaptan began only 5 minutes after the start of experiment in the medium containing methionine, but it began after 12hrs in the medium containing 1-cystine and glucose. According to Birkinshaw, Findlay and Webb5) methyl mercaptan was found in the medium containing glucose, sulfate and other mineral salts, inoculated by Schizophyllum commune. In the same cultural condition as given above, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide were detected by Challenger and Chartons 5) from the data presented above, in addition to microbiological formation of methyl mercaptan from methionine, the possibility cannot be excluded of methyl mercaptan formation by microbes from cystine, sulfate or hydrogen sulfide in the medium containing one of organic compounds such as sugars, glycerin, histidine and ethyl alcohol, etc.  相似文献   

12.
Because of its significant role in the enzymatic and physiological activities of the plant body, manganese has received the attention of several workers. Though manganese may be present in appreciably large quantities, its availability to plants is controlled by various soil properties, the dominant ones among them being pH, calcium carbonate, clay and organic matter present in the soil (BISWAS, (1), (2), LEEPER, (6)).  相似文献   

13.
In a previous communication from this laboratory it has been indicated that mint plants respond typically to different environmental conditions (day length and temperature) by marked alterations in growth, and synthesis of essential oil (SINGH and SINGH, 1968a (1)). Similar work on M. piperita L. carried out by several workers clearly shows that the mineral nutrition and metabolism of this plant are equally affected by environmental changes (CRANE and STEWARD, 1962 (2) ; RABSON, 1965 (3) ; STEWARD et al. 1959 (4)), and the metabolic consequences which flow from deficiencies of nutrient elements are greatly influenced by these factors, e. g., lack of phosphorus under short days is accompanied by greater accumulation of amides than under long days and, therefore, causes decrease in other soluble constituents, viz. amino acids (CRANE and STEWARD, 1962).  相似文献   

14.
The vitamin B(6) compounds pyridoxine (PN), pyridoxamine (PM), pyridoxal (PL), and pyridoxamine 5'-phosphate (PMP) inhibited the diphenolase activity of mushroom tyrosinase. PM showed the highest inhibition; the control activity was inhibited by 38% at 1.5 mM. Each PL, PN, and PMP showed about 30% inhibition at the same concentration. Lineweaver-Burk plots showed that PM and PN were mixed-type inhibitors with K(I) values of 4.3 and 5.2 mM, respectively. Because PM and PN cannot form a Schiff base with a primary amino group of the enzyme, their inhibition is not attributable to the formation of the Schiff base. Alternatively, their quenching function of reactive oxygen species (ROS) was postulated to be responsible for the inhibition. Thus, the inhibitory effect of ROS was examined. The representative singlet oxygen quenchers l-histidine, sodium azide, Trolox, and anthracene-9,10-dipropionic acid (AAP) inhibited the activity. The specific scavenger of superoxide, proxyl fluorescamine, also inhibited the activity. The scavengers of hydroxyl radical, d-mannitol and dimethyl sulfoxide, showed no inhibition. The fluorescence of AAP was decayed during the diphenolase reaction, and PM inhibited the decay. AAP was also a mixed-type inhibitor. The results showed that the vitamin B(6) compounds inhibited the diphenolase activity by quenching ROS (probably singlet oxygen) generated during some reaction step of the diphenolase reaction.  相似文献   

15.
The addition of exogenous proline (10 mm) to Na100-saline culture medium, modified LS medium (Linsmaier and Skoog 1965: Physiol. Plant., 18, 100–127) with 100 mm NaCl promoted the growth of tobacco (Nicotiana tabacum L., cv. Bright Yellow-2) suspension cells unadapted to salt stress without maintaining a high ratio of K+ to Na+ ions under salinity conditions. The addition of exogenous glutamic acid or alanine were not comparable to that of exogenous proline. The proline contents of the NaCl-unadapted cells became much higher when the cells were grown in Na100-saline culture medium with 10 mm proline than when the cells were cultured without proline. The accumulation of K+, Na+, counter ions was sufficient to compensate for the increase of the water potential of the cells caused by salinity. These results suggest that exogenous proline does not act as a nitrogen store and that proline may act as a protectant for enzymes and membranes against salt inactivation rather than as a compatible solute in tobacco suspension cells.  相似文献   

16.
Inorganic pyrophosphatase activity in three soils decreased when exchangeable and soluble metals were removed by leaching with in NH4OAc (pH 8). The effect of added metal ions at various concentrations in the leached soils showed that, at certain concentrations, Ba2+, Ca2+, Co2+, Mg2+, Mn2+, Ni2+ and Zn2+ promoted, K+ and Na+ had no effect, and Fc2+ and Cu2+ decreased pyrophosphatase activity. At high concentrations (>50 mM). Co2+, Mn2+, Ni2+ and Zn2+ inhibited pyrophosphatase activity in two soils. The concentration of metal ion needed for optimum activity of pyrophosphatase varied among the soils. The efficiency of the metal ions at optimum concentrations (average percentage increase for three soils in parentheses) in promoting pyrophosphatase was Ca2+ (47) > Mg2+ (42) > Ba2+ = Co2+ (29) > Ni2+ (27) > Zn2+ (20) > Mn2+(16). Pyrophosphatase activity in two leached soils adjusted to 50, 75, 100 or 150 mM PPi and Ca2+ or Mg2+ concentrations from 0 to 250 mM was at an optimum when the metal ion: PPi ratio was 1:1. Soil pyrophosphatase in the presence of 200 mM CaCl2 or MgCl2 was protected against inactivation by heat (90 C for up to 30 min).  相似文献   

17.
Soil humus plays a significant role in the cation exchange of a soil. YOSHIDA (1) showed that, as a general rule, divalent ions such as calcium and magnesium were adsorbed more strongly onto humus than monovalent ions such as ammonium and potassium in an ion-exchange reaction. He did not, however, describe the behavior of heavy metal ions. BREMNER et al. (2) first suggested that soil organic matter forms complexes with polyvalent cations. HIMES and BARBER (3) found that soil organic matter reacts with divalent metal ions in a manner similar to the chelation reaction. Reviews of the soil organic matter-metal complex have been written by BREMNER et al. (2) and KAWAGUCHI, MATSUO and KYUMA (4).  相似文献   

18.
Attempts have long been made to study the effect of mineral nutrition on the metabolic substances in excised roots from a numcer of plant species, but very little attention has teen given to an approach to the problem by using the bleeding sap from crop plants. Recently, however, an increasing number of reports about the occurrence of organic substances in bleeding sap from crop plants has completely revised an old view that xylem sap was essentially a rather dilute aqueous solution of inorganic salts. Evidence has already been obtained which suggests a significant role for the root system as a centre of metabolism and an upward transport of metabolites from the root via the xylem to the leaf. Although analyses of the nitrogenous compounds present in bleeding sap from herbaceous plants have shown glutamine and asparagine to be the most important constituents, in some species of plants nitrate nitrogen may be a predominant nitrogenous compound. Besides ami des and nitrate, the presence of amino acids in bleeding sap has ceen shown by Kulayeva, Silina, and Kursanov 1) for pumpkins, Wieringa and Bakhuis 21 for Lupins, and DIE3) for cucumbers and tomatoes.  相似文献   

19.
Kursanov et al. conducted a series of studies on the CO2 uptake by roots and translocation and uilization in plant, using carbon-l4 labelled CO2. Kursanov, Kuzin and Mamul1) first studied the uptake of CO2 by the roots of intact bean seedlings and found that after 18-hours exposure in the light, most of the radioactive carbon was translocated upwards. Later on, in a more detailed paper2) these Russian workers estimated that under their experimental conditions, the amount of CO2 absorbed by roots is as much as 25 per cent of that taken up from the atmosphere by leaves. They also reported that soluble carbonates supplied as a fertilizer increased the yield of bean, barley, potato and sugar beet by 15 to 18 per cene). In addition Grinfeld 4) stated that 30–50 kg of CO2 per hectare, dressed as ammonium carbonate, increased the yield of sugar beet by 7 to 16 per cent.  相似文献   

20.
Abstract

The presence of 4-MeGln in the tulip plant was discovered by ZACHARIUS et al. (1954), and it was found that this amide generally occurred in the leaves of almost all the species of genus Tulipa (FOWDEN and STEWARD 1957a). The 4-MeGln compound has been detected in every part of the tulip plant, i.e., bulb scales, roots, basal plate, young shoots, leaves, stern, and flower (FOWDEN and STEWARD 1957a, b; OHYAMA 1986; OHYAMA et al. 1985, 1988a, b; ZACHARIUS et al. 1954, 1957). Especially 4-MeGln was found to be a major soluble N constituent in the leaves and stem of tulip of the flowering stage (OHYAMA et al. 1985; OHYAMA 1986).  相似文献   

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