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1.
Butter  N. S.  Singh  Gurmeet  Dhawan  A. K. 《Phytoparasitica》2003,31(2):200-203
An insect growth regulator (IGR), lufenuron (Match 5EC), was tested for its toxicity toHelicoverpa armigera on cotton. Potency of the IGR against the larval stage of the pest was demonstrated with respect to larval instars; the LC90 values of 1st, 2nd, 3rd, 4th and 5th instar larvae were 5.63, 7.89, 8.03, 11.39 and 14.76 mg a.i.l −1, respectively. However, different larval instars did not differ significantly with respect to LC50 and LC10. IGR-treated larvae had swollen heads and were significantly smaller (1.5–2.3 mm) than the untreated control (2.9 mm). Larval weight was significantly reduced from 190 mg in the control to 50–70 mg in the lufenuron treatment. IGR treatment in the larval stage significantly affected both pupal length and pupal weight. Pupal duration of the test insect was significantly extended by IGR treatment. Pupal deformities, including an inability to shed the last larval skin and formation of larval-pupal intermediates, occurred following treatment. A significant reduction in adult emergence was recorded. In addition, abnormalities in the form of development of cavities in the forewings of adult were evident. A significant decline in fecundity was noted in the studies. http://www.phytoparasitica.org posting Feb. 3, 2003.  相似文献   
2.
The yield and chemical composition of the seed oil of Celastrus paniculatus were determined by solvent extraction and gas chromatography-mass spectrometry. The yield of crude fatty oil was found to be 45.5% in the mature seeds on dry weight basis. Fourteen compounds, constituting 97.57% of the oil, were identified. The oil was rich in unsaturated fatty acids (70.11%) followed by saturated fatty acids (25.2%). Oleic acid (54.42%), palmitic acid (20.0%), linoleic acid (15.51%), and stearic acid (4.18%) were the main fatty acids in the oil together with four other minor fatty acids. The current study identifies the novel compounds not previously reported in C. paniculatus oil, including 1,4-benzenediol (0.46%), cinnamic acid (0.15%), 2,6-di-tert-butyl-p-benzoquinone (0.03%), butylated hydroxytoluene (0.4%), and eudalene (0.16).  相似文献   
3.
In vegetable brassicas, cytoplasmic male sterility (CMS) system is the most preferred mechanism for hybrid seed production and Ogura cybrid cytoplasm is the only source used widely. Effects of the alien cybrid cytoplasm on important quality traits need to be understood for their effective use in breeding programme. In analysing 38 Ogura cybrid cytoplasm‐based cauliflower CMS lines, it was revealed that introgression of Ogura cytoplasm resulted in significant alteration in important quality traits. Cupric reducing antioxidant activity and ferric reducing ability of plasma values were increased up to 5–10 times in different genotypes. Among 38 analysed CMS lines, concentration of plant pigments such as anthocyanin, total chlorophylls and ascorbic acid was reduced in 21, 17 and 32 genotypes, respectively. However, the concentration of total carotenoids and β‐carotene was elevated in most of the CMS lines and total carotenoid was increased up to 20 times in the CMS line, Ogu13‐85‐2A. The results indicate the role of nuclear–cytoplasmic interaction and mitochondrial genome in determining concentration of different quality traits.  相似文献   
4.
Various factors affecting in vitro regeneration like different carbon sources, different gelling agents, and growth additives were assessed comprehensively for callus induction and plant regeneration for five Indian wheat cultivars using mature embryos as the explants for the first time. The tissue culture responses of cultivars WH-1105, HD-2967, and PBW-343 have not been reported earlier. Besides, the effect of different concentrations of the cytokinin, zeatin has also been optimized. Using the optimized factors, the efficiency of five different varieties, i.e., HD 2967, C 306, RAJ 3765, WH 1105, and PBW 343 was evaluated for regeneration. Modified MS basal medium containing dicamba reduced precocious germination of the embryo and induced embryogenic callus more efficiently. Removal of embryogenic calli from non-regenerable structures during early callus phase improved plant regeneration. These calli on zeatin (1.0 mgl-1) and dicamba (0.1 mgl-1) containing medium showed the highest regeneration frequency (98%) with a maximum of 8-9 shoots per calli. Maltose had the maximum callusing and regeneration percentage than other carbon sources. Various gelling agents did not have any significant difference on the regeneration. Of all the varieties, C-306 and HD-2967 were found to be more regenerative and can be used in transformation experiments.  相似文献   
5.

Neonatal calf mortality is a major concern to livestock sector worldwide. Neonatal calf diarrhoea (NCD), an acute severe condition causes morbidity and mortality in calves. Amongst various pathogens involved in NCD, E. coli is considered as one of the major causes. The study was targeted to characterize E. coli isolates from neonatal calves for diarrhoeagenic Escherichia coli (DEC) types (pathotyping), antimicrobial resistance (AMR) profiling and to correlate with epidemiological parameters. From neonates, a total of 113 faecal samples were collected, out of that 308, lactose fermenting colonies were confirmed as E. coli. Pathotypable isolates (12.3%) were represented by STEC (6.1%), EPEC (2.9%), ETEC (1.9%), EAEC (0.9%) and EHEC (0.3%). Occurrence of STEC was more in non-diarrhoeic calves, whereas ETEC was observed more in diarrhoeic calves. EPEC occurrence was observed in both diarrhoeic and non-diarrhoeic calves. Fishers extract test showed no significant association for occurrence of DEC types to type of dairies, health status, species, breed, age and sex of neonatal calves. Two hundred and eighty isolates were tested for antimicrobial susceptibility. The isolates showed maximum resistance towards ampicillin (55.4%) followed by tetracycline (54.3%), while minimum resistance was observed towards meropenem (2.5%). Multidrug resistant E. coli isolates were found to be 139 (49.6%), and Extended-spectrum beta-lactamase (ESBL) producers were 120 (42.9%). DEC pathotypes like STEC, ETEC, EHEC and EAEC that are also multidrug resistant present in neonatal calves have zoonotic potential and hence are of public health significance.

  相似文献   
6.
Genetic Resources and Crop Evolution - The wild Malus germplasm is considered as a gene reservoir for various biotic and abiotic stresses tolerance/resistance genes, including important novel...  相似文献   
7.
To find effective alternatives to reduce the application of conventional urea (CU), a conventional biofertilizer (CB) preparation (charcoal mixed Azotobacter chroococcum and Bacillus subtilis) and the same biofertilizers entrapped in an organic matrix consisting of cow dung, rice bran, dried powder of neem leaves, and clay soil in 1:1:1:1 ratio and 25% (w/w) saresh (plant gum of Acacia sp.), named as super granules of biofertilizers (SGBF) were applied to cultivate wheat (Triticum aestivum L. cv. ‘WH-711’) in experimental plots. The results revealed that the efficacy of commercially available charcoal mixed biofertilizers could not prove as effective alternative to CU, whereas the same dose of biofertilizers entrapped in the organic matrix, SGBF, resulted in a significant increase in growth and productivity of wheat. It appears that SGBF prepared and applied in this study is an effective organic alternative to the urea for wheat cultivation in semi-arid subtropical agro-ecosystems.  相似文献   
8.
Field experiments were conducted to evaluate the effects of eco-friendly organic matrix entrapped urea (OMEU) on growth, productivity, and yield of rice (Oryza sativa L. cv. Basmati) and soil enrichment in the paddy field at Rohtak (Haryana) located near Delhi. The OMEU prepared in granular form contained cow dung, rice bran (grain cover of Oryza sativa), powder of neem leaves (Azadirachta indica), and clay soil (diameter of particles < 0.02 mm) in 1:1:1:1 ratios and saresh (plant gum of Acacia sp.) as binder along with half of the recommended dose of commercially available soluble urea (free urea; FU). Single basal application of OMEU showed an increase in plant growth in terms of fresh and dry weights, root length, root, leaf and tiller numbers, soluble protein, total N and ammonium in leaves, productivity in terms of grain and straw yield, and nutritional and microbial activities of field soil over free form of urea and no fertilizer application. Nutritional status of rice grains was also improved over the free urea and no fertilizer controls. Our data indicate that OMEU, which is low cost and based on bio-degradable, non-toxic, and locally available agro-waste, can be attempted to replace the conventional use of soluble urea in rice.  相似文献   
9.
Introgression lines (ILs) of groundnut with enhanced resistance to rust and late leaf spot (LLS) recorded increased pod and haulm yield in multilocation testing. Marker‐assisted backcrossing (MABC) approach was used to introgress a genomic region containing a major QTL that explains >80% of phenotypic variance (PV) for rust resistance and 67.98% PV for LLS resistance. ILs in the genetic background of TAG 24, ICGV 91114 and JL 24 were evaluated for two seasons to select 20 best ILs based on resistance, productivity parameters and maturity duration. Multilocation evaluation of the selected ILs was conducted in three locations including disease hot spots. Background genotype, environment and genotype × environment interactions are important for expression of resistance governed by the QTL region. Six best ILs namely ICGV 13192, ICGV 13193, ICGV 13200, ICGV 13206, ICGV 13228 and ICGV 13229 were selected with 39–79% higher mean pod yield and 25–89% higher mean haulm yield over their respective recurrent parents. Pod yield increase was contributed by increase in seed mass and number of pods per plant.  相似文献   
10.
Downy mildew (DM) caused by Peronospora arborescens is the most destructive disease of opium poppy which assumes considerable importance in India and other poppy growing countries. The present study was aimed at identification and evaluation of stable resistance sources of DM in opium poppy. Furthermore, genetic variability and inheritance pattern of DM resistance has also been studied which can help in making strategy for crop improvement. Evaluation of 35 selected germplasm accessions of opium poppy under glasshouse and field conditions during the three consecutive years (2004–2005 to 2006–2007) resulted in identification of two genotypes (I-14 and Pps-1) as highly resistant and stable sources for DM resistance. Genetic studies of DM resistance revealed polygenic control with the dominance of susceptibility over resistance. Significant reciprocal differences were found largely due to maternal transmission of DM resistance indicating the involvement of cytoplasmic genes in addition to nuclear control. Analysis of genetic variability and selection parameters indicated predominance of additive effects for DM resistance and other yield contributing traits. Multivariate analysis resulted in classification of 35 selected accessions into 11 different clusters revealing very high level of diversity among the genotypes. Cluster analysis suggested that hybridization program involving genotypes from cluster V (which included highly resistant genotypes Pps-1 and I-14) and cluster IX (which included highly susceptible Jawahar-16 having good economically important traits like seed yield) could be expected to give best recombinants for improvement in terms of DM resistance and high seed and straw yield in opium poppy. Analysis of selection parameters like heritability and genetic advance also suggested that simple selection methods will be effective in stabilizing resistance traits following hybridization with high yielding genotypes.  相似文献   
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