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121.
Potential of Steinernema carpocapsae(Weiser) as a biological control agent against potato tuber moth,Phthorimaea operculella(Zeller)(Lepidoptera: Gelechiidae)
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The entomopathogenic nematode, Steinernema carpocapsae, was evaluated for control of the potato tuber moth, Phthorimaea operculella, under laboratory conditions. We evaluated different concentrations of S. carpocapsae for control of 2 nd, 3 rd, and 4 th instar P. operculella. The median lethal concentration(LC50) of S. carpocapsae infective juveniles(IJs) to 2 nd, 3 rd and 4 th instar larvae of P. operculella was 200, 363, 181 IJs mL–1, respectively. With the extension of treatment time, the cumulative mortality increased for 2 nd, 3 rd, and 4 th instar larvae and pupae of P. operculella. Fourth instars were the most susceptible for all observation periods. Therefore, our results suggest that S. carpocapsae could be an effective biological control agent for P. operculella. 相似文献
122.
C L Chrisman S R Platt A M Chandra A deLahunta G D Shelton 《Journal of the American Animal Hospital Association》1999,35(3):232-235
Generalized reduction of nociception and conscious and unconscious proprioception were found in an approximately eight-year-old, male, Maltese mixed-breed dog presented for difficulty prehending food and experiencing ataxia of three months duration. Results of needle electromyogram, motor nerve conduction velocity, and cerebrospinal fluid analysis were normal. A diagnosis of sensory polyneuropathy was suspected. No underlying cause could be determined. Neurological signs progressed to quadriparesis over the following four months despite treatment attempts with prednisone and procarbazine. Necropsy confirmed a sensory polyganglioradiculoneuritis, but no inciting cause could be established. 相似文献
123.
W. Erskine S. Chandra M. Chaudhry I.A. Malik A. Sarker B. Sharma M. Tufail M.C. Tyagi 《Euphytica》1998,101(2):207-211
This paper introduces the concept of a bottleneck in lentil (Lens culinaris Medikus) in South Asia and then reviews its rupture.
South Asia is the largest lentil growing region in the world and where indigenous lentils show a marked lack of variability.
This results from its introduction from Afghanistan around 2000 B.C. and it limits breeding progress. Three approaches to
widening the genetic base in the region have been tried, namely plant introduction, hybridization and mutation breeding. Introductions
from West Asia flower as indigenous material matures. The asynchrony in flowering has isolated the local pilosae ecotype reproductively.
However, the introduction of ILL 4605, an early, large-seeded line, has resulted in its release as ‘Manserha 89’ for wetter
areas of Pakistan and its widespread use as a parent in breeding programs in the region. Hybridization between pilosae and
exotic germplasm, primarily at International Center for Agricultural Research in the Dry Areas (ICARDA) followed by selection
in the sub-continent has resulted in cultivars with improved disease resistance and yield in Bangladesh and Pakistan. Mutation
breeding has given new morphological markers and several promising lines. These examples illustrate not only the widening
of the genetic base of the lentil in South Asia, but also the evolution of a breeding program of an international center and
national programs targeted toward specific adaptation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
124.
Ajay Kumar Yadav Sagar Chandra Mandal Arun Bhai Patel Pradip Kumar Maurya 《Aquaculture Research》2019,50(11):3343-3349
An experiment was designed to evaluate the requirement of dietary protein for Reba carp, Cirrhinus reba fingerlings using semi‐purified diet. Five isocaloric diets were prepared containing 20%, 25%, 30%, 35% and 40% level of protein using casein, gelatin as a major protein source. The experiment was conducted for 105 days in triplicates to evaluate the growth, survival, feed utilization, carcass composition of C. reba. Mean weight gain was highest (p < .05) in T3. Specific growth rate was highest in T3 and lowest in T1. Similarly, significantly (p < .05) highest net fish yield were recorded in T3. No significant difference was recorded in survivability. Feed conversion ratio, protein efficiency ratio, feed conversion efficiency and protein conversion efficiency were significantly (p < .05) higher for T3 compared with other treatments. Highest carcass protein and lipid values were recorded in T3. So, conclusion can be drawn that 30% crude protein is optimum for overall performance. Furthermore, broken‐line analysis for specific growth rate, final biomass and net fish yield indicated that dietary protein level of 28.148 to 28.253% is optimum for the best growth performance of fingerling C. reba. 相似文献
125.
126.
Development of durable resistance to soybean rust (SBR) is challenging due to the pathogenic diversity of Phakopsora pachyrhizi populations. The objective of this research was to investigate and confirm the genomic locations of Rpp genes in the Ugandan line UG-5 that confer resistance to different SBR pathotypes. Bulked segregant analysis revealed two genomic regions associated with resistance in a cross with rust-susceptible 'Williams 82'. Composite interval mapping in the F2 and F2:3 populations had a LOD score of 48.7 in a region 0.38 cM away from the estimated location of the Rpp1 locus on chromosome (Chr.) 18. An approximately 23-Kbp interval spanning the Rpp1 locus was flanked by SNP markers ss715632313 and ss715632318. Another interval was identified at the Rpp3 locus on Chr. 6 between markers Satt100 and ss715594488 (2.4 cM) in the F2 population and between Satt100 and ss715594874 (4.3 cM) in the F2:3 population, with a maximum LOD score of 25.6. UG-5 was thus confirmed to have SBR resistance genes at the Rpp1 and Rpp3 loci that can be pyramided into other elite cultivars. 相似文献
127.
Govind Pratap Rao Amar Bahadur Sukhen Chandra Das Hemavati Ranebennur Surabhi Mitra Manish Kumar Shailender Kumar 《Forest Pathology》2020,50(1)
Leaf yellowing symptoms were observed on Acacia mangium in the Sipahijala district of Tripura, India, during June 2017. Symptomatic and asymptomatic leaf samples (three of each) were collected from roadside trees of A. mangium for DNA extraction using the CTAB method. Amplicons of ~1.25 kb and ~480 bp were detected in all the symptomatic samples using the phytoplasma‐specific universal 16S rRNA and secA gene primers. Pair wise sequence analysis of 16S rRNA gene sequences, virtual RFLP and phylogenetic analysis revealed that the phytoplasma strain associated with A. mangium belonged to phytoplasma subgroup 16SrII‐C. This is the first report of an association between the 16SrII‐C subgroup and A. mangium leaf yellowing. 相似文献
128.
Olive barb, Puntius sarana (Hamilton) is a potential candidate species for introduction into the grow-out carp polyculture system 总被引:1,自引:1,他引:0
Joykrushna Jena Pratap Chandra Das Samarjit Kar Tarun KumarSingh 《Aquaculture (Amsterdam, Netherlands)》2008,280(1-4):154-157
The compatibility of olive barb, Puntius sarana (Hamilton) with major carps was studied in grow-out carp polyculture system for one year in a set of nine earthen ponds of 0.08 ha each. Three different species combinations evaluated were Control: catla (Catla catla Ham.), silver carp (Hypophthalmichthys molitrix Valenciennes), rohu (Labeo rohita Hamilton) and mrigal (Cirrhinus mrigala Hamilton) at 0.5:0.5:1:1; T1: catla, silver carp, rohu and olive barb at 0.5:0.5:1:1 and T2: catla, silver carp, mrigal and olive barb at 0.5:0.5:1:1 at combined density of 7500 fingerlings/ha. While survival levels of the carps did not differ significantly in treatments (P > 0.05), silver carp recorded highest survival levels (94–96%) followed by olive barb (87–90%), mrigal (72–74%), rohu (72–73%) and catla (67–69%). The specific growth rate (SGR) and average harvested body weight (ABW) of catla and silver carp did not differ significantly among the treatments revealing their competition with mrigal or olive barb to be minimum. In absence of rohu in T2, both mrigal and olive barb showed higher SGR and ABW revealing minimal competition between these two species, while their lower performance in presence of rohu in Control and T1 indicated inter-specific competition with the latter. Such olive barb–rohu inter-specific competition, however, failed to yield significant effect on growth of rohu as revealed from its non-significant SGR difference in presence and absence of olive barb. The lower FCR (2.54 ± 0.06) and higher treatment biomass production (3418.4 ± 95.0 kg ha− 1 year− 1) in T1 with rohu–olive barb combination compared to T2 with mrigal–olive barb (2.84 ± 0.11; 3155.1 ± 104.7 kg ha− 1 year− 1) indicated feasibility and advantage of culturing rohu with olive barb rather than mrigal in carp polyculture. Further, similar biomass production in Control and T1 also indicated feasibility of replacing mrigal with olive barb in the grow-out carp polyculture system. 相似文献
129.
Three varieties of Pea ( Pimm sativum L.) viz. EC33866 (early), P-116 (medium) and T-163 (late), differing in their flowering and maturity times, were taken for this study. The early variety recorded lower dry matter, CO2 exchange rate and lower yield. The harvest index (HI) was the highest (44 %) in this variety. Though medium and late varieties did not differ significantly in dry matter accumulation and pod yield, they differed in their HI. The HI in the medium variety is 42 % but in the late variety it is only 36%.
The late variety maintained high leaf area, leaf dry weight, high shoot/root, shoot/nodule and root/nodule ratios, increased nodule dry weight and maximum glycolate oxidase activity. But acetylene reduction activity was low, and the harvest index was lowest. On the other hand, in the early variety the dry matter accumulation was lowest but HI was highest. The major reasons for high HI in this variety were translocation of photosynthates to reproductive organs and lower photorespiration as indicated by low glycolate oxidase activity. 相似文献
The late variety maintained high leaf area, leaf dry weight, high shoot/root, shoot/nodule and root/nodule ratios, increased nodule dry weight and maximum glycolate oxidase activity. But acetylene reduction activity was low, and the harvest index was lowest. On the other hand, in the early variety the dry matter accumulation was lowest but HI was highest. The major reasons for high HI in this variety were translocation of photosynthates to reproductive organs and lower photorespiration as indicated by low glycolate oxidase activity. 相似文献
130.
B.R. Singh PhD N. Babu MVSc J. Jyoti MVSc H. Shankar PhD T.V. Vijo BVSc AH R.K. Agrawal PhD M. Chandra PhD D. Kumar MVSc A. Teewari MVSc 《Journal of Equine Veterinary Science》2007,27(6):266-276
We examined 872 equids (445 maintained by low-income individuals and 427 maintained on nine designated equine farms) and, using previously described methods for bacteria, isolated Salmonella from fecal samples of 59 (6.77%) animals. Of the 646 horses, 183 donkeys, and 43 mules that had feces cultured for Salmonella, 42 (6.5%), 7 (3.8%), and 10 (23.3%), respectively, were excreting Salmonella strains in feces. Six horse mares were excreting Salmonella enterica of two different serovars simultaneously. A total of 65 Salmonella enterica isolates belonged to 13 serovars, namely S. paratyphi B var Java (14), S. I. 4, 5, 12, 27: r, i: 1, 5 (11), S. Drogana (8), S. Newport (7), S. Saintpaul (5), S. Lagos (4), S. Typhimurium (5), S. Kottbus (3), S. Bovismorbificans (3), S. Dumfries (2), S. Tshiongwe (1) S. Weltevreden (monophasic) (1), and S. enterica ssp salamae (1). With Salmonella-specific polymerase chain reaction (PCR) using hisJ gene primers, 107 (12.3) fecal samples yielded a specific amplicon of 496 bp. On using PCR, prevalence of Salmonella in donkeys, horses, and mules was 4.9%, 10.8%, and 65.1%, respectively. With both methods of Salmonella detection in feces, prevalence was significantly higher in female than in male donkeys and horses. Salmonella shedding in feces was significantly higher in equids maintained by low-income people than those at designated equine farms. Almost all Salmonella isolates (63 of 65) had multiple-drug-resistance (MDR, resistance to three or more drugs). Salmonella isolates were commonly resistant to sulfamethoxazole (90.8%), tetracycline (70.8%), doxycycline (67.7%), furazolidone (66.2%), and colistin (55.4%). A few isolates had resistance to trimethoprim (3.1%), ciprofloxacin (3.1%), ceftriaxone (3.1%), ceftazidime (3.1%), cefoperazone (3.1%), chloramphenicol (4.6%), cefotaxime (6.2%), gentamicin (9.2%), ampicillin + cloxacillin (9.2%), cotrimoxazole (13.8%), kanamycin (13.8%), amoxicillin + clavulanic acid (16.9%), imipenem (16.9%), ampicillin (18.5%), amikacin (23.1%), neomycin (27.7%), nalidixic acid (33.8%), and streptomycin (36.9%). With the exception of 13 Salmonella isolates of S. Drogana (4), S. Newport (4), S. I. 4, 5, 12, 27: r, i: 1, 5 (4) and S. Kottbus (1) serovars, all had one or more than one plasmid. Molecular weight of plasmids ranged between 3 kDa and >87 kDa. One heavy plasmid (≥87 kda) was present in all the 52 plasmid-positive strains. Presence of plasmid could not be correlated with MDR in Salmonella isolates from equids. 相似文献