Row spacing impacts the critical period for weed control in cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis>)     

Nihat Tursun  Avishek Datta  Selvi Budak  Zekeriya Kantarci  Stevan Z. Knezevic 《Phytoparasitica》2016,44(1):139-149

The knowledge on the critical crop-weed competition period is important for designing an efficient weed management program. Field studies were conducted in 2012 and 2013 at the Agricultural Research Institute, Kahramanmaras, Turkey to determine the effects of three row spacing (50, 70 and 90 cm) on the critical period for weed control (CPWC) in cotton. A four parameter logistic equation was fit to data relating relative crop yield to both increasing duration of weed interference and length of weed-free period. The relative yield of cotton was influenced by the duration of weed-infested or weed-free period, regardless of row spacing. In cotton grown at 50 cm row spacing, the CPWC ranged from 117–526 growing degree days (GDD) (V2–V11 growth stages) in 2012 and 124–508 GDD (V2–V10) in 2013 based on the 5% acceptable yield loss level. At 70 cm row spacing, the CPWC ranged from 98–661 GDD in 2012 (V2–V13) and 144–616 GDD (V2–V12) in 2013. At 90 cm row spacing, the CPWC ranged from 80–771 GDD in 2012 (V1–V14) and 83–755 GDD (V1–V14) in 2013. In order to obtain a 95% weed-free yield, the weed management should start at 16 days after crop emergence (DAE) and continued until 52 DAE (V2–V11) for crops grown in 50 cm row spacing, 15 and 60 DAE (V2–V13) for 70 cm row spacing and 11 and 67 DAE (V1–V14) for crops grown in 90 cm row spacing. This suggests that cotton grown in narrow row spacing (50 cm) had greater competiveness against weeds compared with wider row spacing (70 and 90 cm). Cotton growers can benefit from these results by improving cost of weed control through better timing of weed management.  相似文献   

Fusarium crown rot under continuous cropping of susceptible and partially resistant wheat in microcosms at elevated CO2     

M. Khudhair  P. Melloy  D. J. Lorenz  F. Obanor  E. Aitken  S. Datta  J. Luck  G. Fitzgerald  S. Chakraborty 《Plant pathology》2014,63(5):1033-1043

This study examines the CO₂‐mediated influence of plant resistance on crown rot dynamics under continuous cropping of partially resistant wheat line 249 and the susceptible cultivar Tamaroi. Disease incidence, severity, deoxynivalenol and Fusarium biomass were assessed after each cycle in microcosms established at ambient and 700 mg kg^?1 CO₂ using soil and stubble of these wheat lines from a field experiment with free to air CO₂ enrichment. Monoconidial isolates from wheat stubble were collected initially, and after five cropping cycles, to compare the frequency and aggressiveness of Fusarium species in the two populations. Aggressiveness was measured using a high‐throughput seedling bioassay. At elevated CO₂, the higher initial incidence in Tamaroi increased with cropping cycles, but incidence in 249 remained unchanged. Incidence at ambient CO₂ did not change for either line. Elevated CO₂ induced partial resistance in Tamaroi, but not in 249. Increased Fusarium biomass in wheat tissue at elevated CO₂ matched raised deoxynivalenol of the stem base in both lines. After five cycles of continuous wheat cropping, aggressiveness increased in pathogenic F. culmorum and F. pseudograminearum by 110%, but decreased in weakly pathogenic F. equiseti and F. oxysporum by 50%. CO₂ and host resistance interactively influenced species frequency, and the highly aggressive F. pseudograminearum became dominant on Tamaroi irrespective of CO₂ concentration, while its frequency declined on 249. This study shows that induced resistance at elevated CO₂ will not reduce crown rot severity, or impede the selection and enrichment of Fusarium populations with increased aggressiveness.  相似文献   

Identification of Stable Reference Genes for Gene Expression Studies Using Quantitative Real Time PCR in Buffalo Oocytes and Embryos     

Poonam Yadav  Arpana Verma  Dheer Singh  Sachinandan De  Tirtha Kumar Datta 《Reproduction in domestic animals》2012,47(6):e88-e91

The present study was aimed to validate expression stability of 6 housekeeping genes (viz. YWHAZ, SDHA, GAPDH, RPS15, RPS18 and RN18S1) in the oocytes and embryos of different stages in buffalo. A modified Trizol protocol was optimized for RNA isolation from as few as five oocytes. The expression level of selected genes was studied by an optimized real time PCR using DCT method and their stability of expression was evaluated by Microsoft Excel based visual application, geNORM. The analysis revealed that the RPS15 and GAPDH were the most stable genes across different samples. Also, the geometric mean of three genes (i.e. RPS15, RPS18 and GAPDH) were found suitable for normalization of real time PCR data from buffalo oocytes/embryos. The information would help in more accurate interpretation of gene expression data from oocytes/embryos towards understanding the molecular events in these cells during development.  相似文献   

Solubility Relationships of Iron and Evaluation of its Fertility Status in Degraded Soils     

Babu Lal Meena  Raj Kumar Rattan  Siba Prasad Datta 《Communications in Soil Science and Plant Analysis》2017,48(9):1059-1067

This study was conducted to determine the solubility of iron (Fe) and identify the solid phases responsible for controlling its solubility in these soils by using Baker soil test (BST) computer program. The results indicated that the ferric ion (Fe³⁺) activity in all the soils, except the acidic ones, nearly approached the theoretical solubility line of known minerals, namely soil-Fe, amorphous-Fe, maghemite, and lepidocrocite. Solubility of Fe in acid soils of Ranchi (soil 3) and Cooch-Behar (soil 6) did not match the theoretical solubility lines of any of the known minerals. The acidic soils of Ranchi and Cooch-Behar were sufficient for Fe with respect to both quantity and intensity factor based on BST rating, while alkaline (soil 1) and calcareous (soil 5) were sufficient in reserve Fe; deficiency of iron still could be suspected because of high pH. These findings elucidate the role of solid phase controlling iron solubility in soil solution of degraded soils.  相似文献   

Nanoclay polymer composites loaded with urea and nitrification inhibitors for controlling nitrification in soil     

Kirti Saurabh  Samar Chandra Datta  Ahammed Shabeer Thekkumpurath  Rajesh Kumar 《Archives of Agronomy and Soil Science》2019,65(4):478-491

Nanoclay polymer composites (NCPCs) were synthesized with partially neutralized acrylic acid and bentonites and loaded with urea and nitrification inhibitors (NIs) to act as a slow release carrier of nitrogen (N). The resulting product was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The XRD of NCPCs revealed that the bentonite layers were completely exfoliated and dispersed in the composite after the polymerization. The water absorbency of pure polymer (Acrylic acid + Acrylamide) was 197.53 g g^?1 and 137.75 g g^?1 by nanocomposite (8% nanobentonite) in distilled water. The nitrification inhibition ability of these NCPCs was evaluated by incubation study for 60 days in laboratory at 28°C and 50% water-holding capacity. The Schiff base -NCPCs were most effective at inhibiting nitrification (30–87%) compared to dicyandiamide and Neem oil. A column study was performed to know the movement of NH₄-N and NO₃-N at three different depths. Result showed that the Schiff base -NCPC decreased nitrate movement by 78.5% at the depth of 5 cm in soil column. The slow release of nitrogen and good water retention capacity confirmed that these NCPCs can be viably exploited for application in agriculture.  相似文献   

Inheritance of temperature-sensitive leaf rust resistance and adult plant stripe rust resistance in common wheat cultivar PBW343     

Dibendu Datta  S. K. Nayar  M. Prashar  S. C. Bhardwaj 《Euphytica》2009,166(2):277-282

Genetic analysis of common wheat cultivar PBW343 confirmed temperature-sensitive leaf rust resistance and adult plant stripe rust resistance. At low temperatures, PBW343 was resistant to P. triticina (Ptr) pathotype (pt.) 121R63-1, and at high temperature it was resistant to Ptr pt. 121R127. The low temperature resistance to pt. 121R63-1 was attributed to interaction between dominant and recessive genes. The dominant gene involved in low-temperature resistance to pt. 121R63-1 also conferred resistance to pt. 45R35. The high-temperature resistance to Ptr pt. 121R127 was governed by a different single partially dominant gene. Agra Local (a commonly used susceptible check) and IWP94 (a leaf rust differential used in India) are also resistant to pt. 121R127 at high temperatures. An allelism test indicated that PBW343 and IWP94 possessed a common gene for high temperature resistance to this pathotype. The adult plant stripe rust resistance against P. striiformis (Pst) was possibly conferred by one gene in addition to Yr27.  相似文献   

Bt籼稻对褐飞虱取食、产卵行为的影响   总被引：4，自引：2，他引：4       下载免费PDF全文

陈茂  叶恭银  胡萃  Datta S. K. 《植物保护学报》2003,30(4):365-370

比较了褐飞虱在2个Bt籼稻纯合品系，即TT9-3、TT9-4，及亲本对照IR72上的取食和产卵行为。结果表明，在选择性条件下，褐飞虱于稻株上的着虫比率在Bt籼稻与对照间无显著差异，而稻株中部和整个叶鞘的取食刺探痕数、产卵选择比率和产卵量则均以Bt籼稻显著为低。在非选择性条件下，稻株叶鞘上的取食刺探痕数在Bt籼稻与对照间无显著差异，而排泄的蜜露量则多以Bt籼稻尤其是TTP9-4显著为少。可见，供试的2个Bt籼稻品系不利于褐飞虱的取食或产卵，表现有抗褐飞虱的能力。  相似文献   

Influence of puberty and egg formation upon concentration of glycogen and total solids in the ovary and fallopian tube in WLH birds.     

M R Prabhakar  I C Datta 《The Indian veterinary journal》1976,53(6):423-425

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Development of a Competitive Quantitative PCR Strategy for Evaluating the Expression Stability of 18s rRNA during In Vitro Maturation of Buffalo (Bubalus bubalis) Follicular Oocytes     

APS Aswal  TK Datta  S Raghav  S De  P Yadav  SL Goswami 《Reproduction in domestic animals》2007,42(2):195-201

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Growth characteristics of multipurpose tree species, crop productivity and soil properties in agroforestry systems under subtropical humid climate in India     

M. Datta  N. P. Singh 《林业研究》2007,18(4):261-270

Multipurpose tree species （MPTs） were studied in an agroforestry arboretum under subtropical humid climate in Northeast India. Out of 12 MPTs planted under agroforestry systems, Acacia auriculiformis in spacing of 2 m × 2 m （2500 stems·hm^-2） could have the potentiality to meet the timber/fuelwood requirement due to its high wood production of 635 m^3·hm^-2 with mean annual increment （MAI） of 2.54×10^-2 m^3.treel.a^-1 in a short rotation period of 10 years. Thus, A. auriculiformis is a short rotation forest tree species suitable to grow in subtropical humid climate. On the other hand, at 16 years of age, Eucalyptus hybrid and Michelia champaca in spacing of 3 m × 3 m （1111 stems.hm^2） produced appreciably high timber volume of 315 m^3.hm^-2 and 165 m^3.hm^-2 with MAI of 1.77×10^-2 m^3.tree^-1·a^-1 and 0.92×10.2 m^3.tree^-1.a^-1, respectively. At 16 years of age, Gmelina arborea produced a timber volume of 147 m^3.hm^-2 with MAI of 1.47×10^-2 m^3.tree^-1.a^-1 followed by Samania saman （140 m^3.hm^-2）, Albizziaprocera （113 m^3·hm^-2） and Tectona grandis （79 m3.hm^-2） with MAI of 1.40, 1.13 and 0.78 × 10^-2 m^3 .tree^-1a^-1, respectively in 4 m × 4 m spacing （625 stems.hm^-2）. Gliricidia maculata and Leucaena leucocephala could be used as live fences around the farm boundary to supply their N-rich leaves for mulch as well as manure to crops. In agroforestry arboretum, direct seeded upland rice （Oryza sativa - variety, AR-11）, groundnut （Arachis hypogaea - variety, JL-24） and sesamum （Sesamum indicum - variety, B-67） were grown during the initial period upto 8 years of tree establishment. Under other MPTs, there was a reduction in crop productivity as compared to open space. After 8 years of tree establishment, horti-silvi and silvi-pastoral systems were developed and pineapple （Ananas comosus - variety Queen）, turmeric （Curcuma longa -variety RCT -1） and cowpea （Vigna sinensis - variety Pusa Barsati） as forage crop were raised. The productivity of p  相似文献