Effect of Split Nitrogen Application on Growth and Yield of Wheat (T. aestivum L.) Genotypes with Different N-Assimilation Potential     

M. Z. Abdin    K. C. Bansal  Y. P. Abrol 《Journal of Agronomy and Crop Science》1996,176(2):83-90

A field experiment was conducted with different nitrogen regimes to assess the growth and yield performance of wheat genotypes which differ in nitrate assimilation potential. Genotypic differences in biomass accumulation were observed at different growth stages. The nitrogen treatment had little effect on biomass accumulation at early stages of growth, while at later stages of growth there was enhanced biomass accumulation when N was applied in more than two splits. On an average, genotypes with high nitrate reductase activity (the 'HNR' genotypes) accumulated 14.2 % more biomass than the genotypes with low nitrate reductase activity ('LNR' genotypes) when an extra dose (40 kg N ha⁻¹) of nitrogen was given at the time of anthesis. The application of nitrogen in more than two splits increased grain yield of both 'HNR' and 'LNR' genotypes mainly by increasing grain weight per ear. The application of an extra dose of nitrogen (40 kg N ha⁻¹) at the time of anthesis increased grain yield of 'HNR' genotypes by 38.5 % as compared to 'LNR' genotypes.  相似文献   

Agroforestry techniques for the rehabilitation of degraded salt-affected lands in India     

G. Singh  N. T. Singh  I. P. Abrol 《Land Degradation \u0026amp; Development》1994,5(3):223-242

The development of appropriate technologies for the judicious use of India's 8.11 million ha of salt-affected lands would give increased food, fodder and fuelwood production. A sizeable portion of the salt-affected lands of the Indo-Gangetic plain have been reclaimed through chemical amendments and are being commercially used for arable farming. However, large areas of salt-affected common lands, village and government lands and waste lands near cities, along railway tracks and roads do not have any productive use. Owing to their sparse vegetative cover such lands are vulnerable to further degradation and can be a source of runoff causing floods, especially where cows congregate. Research at the Central Soil Salinity Research Institute, Karnal has generated agroforestry techniques which could enable the economic exploitation of such marginal lands. This paper deals with various aspects of these techniques, which have been applied to over 50 000 ha by 1994. Based on eight to ten years of growth and biomass figures, the most salt-tolerant woody species identified were: Prosopis juliflora, Acacia nilotica, Casuarina equisetifolia, Tamarix articulata, Leptochloa fusca (a palatable forage grass which was found to be a promising primary colonizer of salt lands). Agronomic practices for the successful establishment of trees such as planting methods, amendment use, irrigation, spacing and lopping schedules are discussed. A Prosopis juliflora-leptochloa fusca silvipastoral model was found to be excellent for fuelwood and forage production and for the amelioration of high pH soils. This system, when followed for little more than four years, reclaims alkali soils to such an extent that normal agriculture crops such as Trifolium alexandrinum and T. resupinatum can be grown successfully. A ridge-trench system of tree planting was found to be helpful in alkali soils, the in situ rainwater conservation it led to assisting biomass production. Eucalyptus tereticornis, Populus deltoides and Tectona grandis based agroforestry were promising for reclaimed salt-affected lands. The short- and long-term effects of various tree plantations on the physicochemical properties of the soil and on soil-water relations are also discussed. Agroforestry options for the development of salt-affected lands found in various agroclimatic zones of India are explored.  相似文献   

Studies on pesticides based on coumarin. III. Synthesis and antifungal activity of substituted 4-methyl-coumarins and related compounds     

Rajvir Singh  Mrs V. Abrol  Bharat B. Gupta  Om P. Malik 《Pest management science》1988,23(2):103-107

A series of substituted 4-methylcoumarins was synthesised and the members tested for their toxicity towards mycelial growth of seven phytopathogenic fungi in culture. Rhizoctonia solani, Alternaria alternata and Fusarium solani exhibited maximum sensitivity to these compounds whereas Pythium aphanidermatum, Colletotrichum falcatum, Drechslera oryzae and Macrophomina phaseolina were relatively less sensitive. 6-Ethyl-3-n- propyl-7-hydroxy4-methylcoumarin ( I ) was relatively toxic towards all fungi except C. falcatum, P. aphanidermatum and M. phaseolina. The 6-n-butyl ( III ) and 6-(1, 1, 3, 3-tetramethylbutyl) ( VI ) derivatives were highly toxic to R. solani with EC₅₀, values of lμg ml^?1.  相似文献   

Evaluation of coastal sandy soils and their saline ground waters for afforestation: A case study from India     

H. S. Gill  I. P. Abrol 《New Forests》1990,4(1):37-53

A study was conducted in coastal Andhra Pradesh to evaluate current practices and suitability of coastal sandy soils for raising tree plantations. Poor soil moisture retention characteristics of these soils make irrigation an essential, but costly silvicultural practice for obtaining desirable establishment and growth. Saline ground water is the only available source of irrigation. Its use seems safe and successful in such soils. The farmers have adopted a specialized manual splashing technique (Doruvu) of seepage pits for irrigating tree plantations in their establishment phase. This technique was observed to be well suited to the sandy soils. Casuarina equisetifolia and Eucalyptus tereticornis were the two most popular species being afforested. E. camaldulensis is also in an introduction phase. Comparison of growth performance and biomass accumulation by C. equisetifolia and E. tereticornis plantations at different growth stages showed the former to be significantly better than the latter. Build up of the soil organic carbon was also found to be markedly more in comparable C. equisetifolia plantations than those of E. tereticornis. Similarly, the blanketing influence of C. equisetifolia plantations was observed to modify soil temperature extremes considerably more than in the case of E. tereticornis. The findings, indicated a vast scope for utilization of coastal sandy soils for afforestation with the successful use of saline ground waters.  相似文献   

Estimating nocturnal ecosystem respiration from the vertical turbulent flux and change in storage of CO₂     

Eva van Gorsel  Nicolas Delpierre  Ray Leuning  Andy Black  J. William Munger  Steven Wofsy  Marc Aubinet  Christian Feigenwinter  Jason Beringer  Damien Bonal  Baozhang Chen  Jiquan Chen  Robert Clement  Kenneth J. Davis  Ankur R. Desai  Danilo Dragoni  Sophia Etzold  Thomas Grünwald  Lianhong Gu  Bernhard Heinesch  Lucy R. Hutyra  Wilma W.P. Jans  Werner Kutsch  B.E. Law  Monique Y. Leclerc  Ivan Mammarella  Leonardo Montagnani  Asko Noormets  Corinna Rebmann  Sonia Wharton 《Agricultural and Forest Meteorology》2009,149(11):1919

Micrometeorological measurements of nighttime ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u_*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u_*-threshold filtering technique. Tellus 59B, 397–403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (F_C) and change in storage (F_S) of CO₂ in the few hours after sundown. The sum of F_C and F_S reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration R_Rmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of F_c + F_s extrapolated to zero light, R_LRC, and (3) with a detailed process-based forest ecosystem model, R_cast. At most sites respiration rates estimated using the u_*-filter, R_ust, were smaller than R_Rmax and R_LRC. Agreement of our approach with independent measurements indicates that R_Rmax provides an excellent estimate of nighttime ecosystem respiration.  相似文献   

Agroforestry on alkali soil: effect of planting methods and amendments on initial growth,biomass accumulation and chemical composition of mesquite (Prosopis juliflora (SW) DC) with inter-space planted with and without Karnal grass (Diplachne fusca Linn. P. Beauv.)     

Gurbachan Singh  I. P. Abrol  S. S. Cheema 《Agroforestry Systems》1988,7(2):135-160

Growth responses of mesquite (Prosopis juliflora (SW) DC.) during establishment stage to planting methods and amendments were studied in a highly alkali soil (Aquic Natrustalf, ESP 94), at the experimental farm of the Central Soil Salinity Research Institute, Karnal in July, 1984. Six combinations of planting methods and amendments with and without Karnal grass (Diplachne fusca Linn. P Beauv) in the inter-row space were compared in a four times replicated field experiment in randomised block design. The mean plant height (MPH), diameter at stump height (DSH), diameter at breast height (DBH), lopped biomass 16 months past planting and total biomass attained in 2 years period were significantly less when inter-row space was planted with Karnal grass. The MPH (cm), DSH and DBH (mm) attained in 2 years period were 319, 43.4 and 15.1 in with grass as compared to 405, 53.4 and 20.3 in without grass treatments. Similarly, the total biomass attained in 2 years was about 3 times more where inter-row space was not planted with grass. Growth was better when mesquite was planted by auger hole and pit methods than in trench plantation, when the original soil was treated with gypsum at 3 kg plant^–1 and then refilled. However, using trenches of dimensions 30 × 30 cm and filled with a mixture of original soil, 3 kg gypsum and 8 kg farm yard manure plant^–1 appeared to be promising method for establishing mesquite plantations on highly deteriorated alkali soils. The effect of amendments on growth decreased in the order gypsum + FYM, gypsum + rice husk, gypsum, control. In two years period, 37 percent mesquite died in the trenches in which the original soil was left unchanged. Effect of treatments on nutrient concentrations and total accumulations in different segments of mesquite is discussed. Karnal grass gave 25.3 t ha^–1 green forage yield in 8 cuts without amendment in a growth period of 26 months proving its great potential as a folder crop for the adverse sites. The inorganic chemical composition of the shoots, including trace elements Fe, Mn, Zn and Cu, is such as to make this species a highly promising plant for the exploitation of alkali soils. Growing Karnal grass with mesquite for a period of about 2 years reduced soil pH and EC significantly and improved organic carbon and available N contents. The grass improved water infiltration rates and moisture storage in the lower layers of the profile.  相似文献   

Agroforestry on alkali soils: Effect on some management practices on initial growth,biomass accumulation and chemical composition of selected tree species     

S. S. Grewal  I. P. Abrol 《Agroforestry Systems》1986,4(3):221-232

This field study started in July 1982 on a typical alkali soil (Aquic Natrustalf, ESP 99.7) examined the growth responses to some management practices in a unified system planned to establish agroforestry. The planting of 3 salt tolerant tree species with two methods: on flat natural surface (FSPB) without rainwater conservation and on ridges (0.6 m high, 1.5 m at top and 2.5 m at base) having parallel trenches of the same section to store 300 mm of monsoon rainwater; constituted the main plot treatments. The tree planting with and without forage grassDiplachne fusca linn. in the inter-row space and planting in shallow (15 × 60 cm) and deep (15 × 180 cm to cross hard pan) augerholes filled with amendment treated soil (2 kg gypsum, 8 kg FYM, 50 g N, 10 g zinc sulphate and original soil) formed the sub and sub-plot treatments replicated 4 times in a split-split plot design.The mean plant height ofEucalyptus tereticornis smith;Acacia nilotica L; andParkinsonia aculeata L. in 2 years period was 273 and 328, 240 and 240 and 211 and 199 cm respectively with and without rainwater conservation. The corresponding height of the 3 tree species was 314 and 287, 250 and 231 and 207 and 203 cm with and without grass in the inter-row space. Similarly the plant height was 247 and 354, 182 and 298, 172 and 238 in shallow and deep augerholes respectively. The tree height and basal diameter differences with and without rainwater conservation and grass growth remained non-significant but deep augerhole planting was markedly superior to the shallow augerhole planting. The 2 year biomass accumulation also followed the same trend. The grass competed with trees for moisture during hot dry summer months and increased plant mortality particularly in the shallow augerholes and more so on ridges. The plant roots, essentially, remained confined to the amended soil of the augerholes in FSPB but proliferated in the loose soil of ridges or grass and submergence ameliorated surface soil of trenches.Acacia nilotica accumulated low sodium and had the lowest Na:Ca and Na:K ratio. It was found more promising than eucalyptus and parkinsonia as it experienced low mortality and had better chemical constitution to tolerate adverse alkali soil environment. The rainwater conservation system needed further evaluation before drawing final conclusions.  相似文献   

Dehydration of Seeds in Intact Tomato Fruits     

McIlrath WJ  Abrol YP  Heiligman F 《Science (New York, N.Y.)》1963,142(3600):1681-1682

Although the moisture content of the placenta and pericarp of tomato fruits older than 15 days never dropped below about 94 percent, the seeds dehydrated to approximately 50 percent moisture as these organs developed and matured. There was a loss in the total amount, as well as the percentage, of water per seed. Part of this dehydration was mediated by the seeds themselves and part appeared to be due to other portions of the fruit.  相似文献   

Impact of tillage and mulch management on economics,energy requirement and crop performance in maize–wheat rotation in rainfed subhumid inceptisols,India     

Peeyush Sharma  Vikas Abrol  R.K. Sharma 《European Journal of Agronomy》2011,34(1):46-51

Different tillage systems (conventional, minimum, raised bed and no tillage) and four mulch levels (control, polythene, straw and soil) were compared in maize (Zea mays) and wheat (Triticum aestivum) production for three years on an experimental field (sandy loam) located at Dry Land Research Sub Station, Dhiansar, Jammu. Each treatment was replicated four times in split plot design. The aim of the research was to determine the influence of tillage and mulch practices on economics, energy requirement, soil physical properties and performance of maize and wheat. Tillage methods significantly affected the soil physical properties as change in soil moisture contents and infiltration rate of soil was recorded. The soil moisture contents in minimum tillage (MT) were maximum (12.4%, 16.6%) in surface soil as compared to conventional tillage (CT) in maize and wheat crops, respectively. Comparing to the CT infiltration rate was (1.16times, 1.21times and 1.11times) higher in minimum tillage (MT), no tillage (NT) and raised bed (RB), respectively in kharif season. Similar results were also found in rabi season. The greatest maize yield of 1865 kg ha^?1 was achieved with CT system while not significantly lower yield was achieved with MT system (1837 kg ha^?1). However, wheat yield was recorded higher in MT as compare to the CT system. Comparing to the energy requirement of different operations, MT required 34.3% less, NT 31.1% less and RB 46.0% less than the CT system. MT system saved 2.5 times energy in tillage operation compared to the CT system. The economic analysis also revealed that the maximum benefits could be obtained from MT (EUR 202.4 ha^?1) followed by RB (EUR 164.2 ha^?1) and NT (EUR 158.3 ha^?1) and lowest in CT (EUR 149.5 ha^?1). Benefit-cost ratio was highest in MT (0.71) and lowest in CT (0.44). Results revealed that mulch significantly affected the soil physical properties and growth of maize. The maximum soil moisture content, infiltration rate and grain yield of maize and wheat recorded higher in mulching practices over no mulch treatment. Polythene mulch and straw mulch were almost equally valuable in maize and wheat sequence. Tillage (minimum) and mulch (polythene and straw) have pronounced effect on soil physical properties (improved infiltration rate and conserve soil water), energy requirement, economics and growth of maize and wheat.  相似文献   

Carbon dioxide assimilation in urea‐treated wheat leaves     

K. C. Lakkineni  A. Sivasankar  P. A. Kumar  T. V. R. Nair  Y. P. Abrol 《Journal of plant nutrition》2013,36(10):2213-2217

Application of 10 mM urea to the flag leaf of wheat plants enhanced in vivo urease activity several fold. Photosynthetic rate was also increased considerably. There were significant differences in the leaf internal carbon dioxide (CO₂) concentrations between the urea‐treated and untreated leaves. The finding that carbon (¹⁴C) was detected in the ethanol extract of the leaves fed with ¹⁴C‐urea suggests that CO₂ released from urea is re‐fixed by the leaves.  相似文献