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71.
The degradation of total oil and grease (TOG) in crude oil-contaminated soil in the presence of Cyperus brevifolius (Rottb.) Hassk was investigated in a net house study. C. brevifolius plants were transplanted in to spiked soil containing 8% (w/w) crude oil. The capability of plant for enhancing the biodegradation process was tested in pots containing fertilized and unfertilized soil over a 360-day period. Analysis of the degradation of hydrocarbon contaminants, plant growth, and biomass was conducted at 60-day interval. In the presence of contaminants, plant biomass and height were significantly reduced. The specific root surface area was reduced under the effects of crude oil. Concerning TOG content in soil, C. brevifolius could decrease up to 86.2% in TA (crude oil-contaminated soil with fertilizer) and 61.2% in TC (crude oil-contaminated soil without fertilizer). In the unvegetated pots, the reduction of TOG was 13.7% in TB (crude oil-contaminated soil with fertilizer) and 12.5% in TD (crude oil-contaminated soil without fertilizer). However, biodegradation was significantly more in vegetated pots than in unvegetated pots (p?=?0.05). The addition of fertilizer had positive effect on TOG degradation in the presence of C. brevifolius compared to the unfertilized treatments. Thus, there was evidence of C. brevifolius enhancing the biodegradation of crude oil in soil under the conditions of this experiment.  相似文献   
72.
Summary Genetic analysis of cytoplasmic male sterility systems in sorghum was undertaken by evaluating a set of 25 A×B crosses and another set of 171 A×R crosses. Male steriles included diverse sources reported from U.S.A. and India. Fertility restoration in crosses was assessed by studying pollen sterility under microscope and seed setting under selfed earheads. Male fertility restorers are identified for diverse cytoplasms. Accordingly the diverse cytoplasms are grouped and listed in the increasing order of their sterility as A1 & CK 60A A2 A4 M31-2A & M35-1A (A4 tentative) A3 & VZM2A G1A (A5 tentative) and consequently fertility restoration also becomes difficult in the same order for utilization in the breeding programmes. Among the non-milo cytoplasms, A2 among exotics and maldandi (M31-2A and M35-1A) among Indian sources, can be utilised for practical exploitation in breeding programmes.  相似文献   
73.
74.
Limited biochemical information is available on soybean accessions that have seed protein content greater than 45% of the seed dry weight. SDS-PAGE analysis of seed proteins from nine soybean accessions revealed significantly higher amount of seed storage proteins in these accessions when compared with that of soybean cultivar Williams 82. High-resolution two-dimensional gel electrophoretic analysis of seed proteins revealed significant differences among several seed storage protein components in these accessions. A total of 51 protein spots were identified using peptide mass fingerprinting (MALDI-TOF MS). The contribution of these proteins to the overall protein content of the accessions was quantified using Delta2D image analysis software. Results showed that among the majority of the nine accessions, the largest difference in higher protein quantity was within the seed 11S storage globulins. The high protein trait from PI407788A was successfully transferred to an experimental line, LG99-469, demonstrating that this trait was transferable and robust.  相似文献   
75.
Wnt signaling has recently emerged as a key factor in controlling stem cell expansion. In contrast, we show here that Wnt/beta-catenin signal activation in emigrating neural crest stem cells (NCSCs) has little effect on the population size and instead regulates fate decisions. Sustained beta-catenin activity in neural crest cells promotes the formation of sensory neural cells in vivo at the expense of virtually all other neural crest derivatives. Moreover, Wnt1 is able to instruct early NCSCs (eNCSCs) to adopt a sensory neuronal fate in a beta-catenin-dependent manner. Thus, the role of Wnt/beta-catenin in stem cells is cell-type dependent.  相似文献   
76.
Hari Om  S. Kumar  S. D. Dhiman 《Crop Protection》2004,23(12):1157-1168
Phalaris minor Retz. (Littleseed canarygrass) is a pernicious weed, which infests several crops during the winter season, particularly the wheat crops in rice–wheat sequence. Considering the limitations of cultural and chemical methods of weed control, the understanding of its biology with respect to different environmental, edaphic and management factors may offer a useful key to strengthen weed management strategies. This review considers various aspects on dormancy, viability and agro-ecology with emphasis on management practices in host and succeeding crops. Due attention has been given to the approaches required to manage the resistant biotypes under present conditions and hence to avoid further escalation of the epidemic. The various studies indicate that P. minor utilizes beneficially the prevailing environmental and management conditions of both the wheat and succeeding rice crop in rice–wheat system for its survival and growth. Its seed is highly sensitive to variable moisture and temperature regimes for germination and exhibits tolerance to anoxia during anaerobic respiration in rice. Tillage options, residue management, spatial–temporal considerations and other factors influence the seed dynamics, pattern and depth of emergence and growth of P. minor. A comprehensive and conceptual understanding of these aspects may provide useful guidelines in formulating cautious and opportunistic weed management strategies.  相似文献   
77.
Summary

Chilli plants cv. Pusa Jwala were inoculated in the nursery beds with three mycorrhizal fungi, Gigaspora calospora, G. margarita and Glomus fasciculatum and transplanted to plots supplied with 0, 25 and 50% of a recommended P level (65 kg ha?1). Uninoculated plants were also transplanted at 0 (Control) and 100% of.the recommended P level. Plant growth, height, shoot dry weight, uptake of P, root colonization and yield of green chillies were measured. Chilli responded well to inoculation and P. G. margarita best improved growth and yield. Inoculation plus 25 and 50% P were equally better than the control and equal to uninoculated plants at 100% P. As much as 50–75% P can be dispensed with by inoculation with mycorrhizal fungi and this represents a considerable economic saving in cost.  相似文献   
78.
The effect of various flavonoids, lectins and phenyl β-d-glucoside on larval survival, weights and the activities of digestive (total serine protease and trypsin) and detoxifying [esterase and glutathione-S-transferase] enzymes of Helicoverpa armigera larvae at 5 and 10 days after treatment (DAT) was studied through diet incorporation assay. Flavonoids (quercetin, cinnamic acid, caffeic acid, chlorogenic acid, catechin, trihydroxyflavone, gentisic acid, ferulic acid, protocatechuic acid and umbelliferone) were incorporated in artificial diet at 100, 500 and 1000 ppm, lectins: groundnut leaf lectin (GLL), concavalin (ConA) and phenyl β-d-glucoside at 2.5 and 5 μg mL?1. Flavonoids such as chlorogenic acid, caffeic acid and protocatechuic acid at 1,000 ppm were more toxic to H. armigera larvae at 10 DAT than quercetin, catechin, cinnamic acid, trihydroxyflavone, gentisic acid, ferulic acid and umbelliferone. Larval growth and development were significantly reduced in H. armigera larvae fed on a diet with GLL and ConA at 5 μg mL?1 compared to the larvae fed at 2.5 and 1.25 μg mL?1 concentrations. The enzyme activities of the larvae were significantly reduced in flavonoid-treated diets. The flavonoids such as chlorogenic acid, caffeic acid, gentisic acid, trihydroxyflavone, catechin and protocatechuic acid, and lectins, GLL and ConA can be utilized in insect control programs.  相似文献   
79.
利用核心种质发挥及评价花生抗黄曲霉资源   总被引:1,自引:0,他引:1  
黄曲霉菌极大地限制全世界的花生生产和产业发展,且生产上抗性品种较少,我国花生育种和生产中的抗性资源缺乏,迫切需要发掘抗黄曲霉菌种质。本研究以中国花生核心种质561份和ICRISAT微核心种质155份,鉴定了黄曲霉侵染和产毒抗性,发掘出抗黄曲霉侵染和产毒种质各8份,包括具优良农艺性状的抗黄曲霉产毒种质51002-6。鉴定结果表明,ICRISAT花生微核心种质中抗黄曲霉侵染和产毒种质的频率高于中国花生核心种质;普通型花生资源中抗黄曲霉侵染种质的频率较高,龙生型资源中抗黄曲霉产毒种质的频率较高。根据SSR分析,鉴定出与生产上推广应用的优良品种中花5号、中花6号、中花12和远杂9102遗传距离较远的抗黄曲霉产毒种质ICG12625和抗侵染种质ICG4750,拓宽了我国花生品种改良的遗传基础。根据抗病基因产物的NBS类型保守域设计简并引物对抗黄曲霉种质的DNA进行PCR扩增、克隆、测序和分析,获得了1条RGA片段。  相似文献   
80.
BACKGROUND: Biopesticides based on Beauveria bassiana (Bals.) Vuillemin hold great promise for the management of a wide range of insect pests. The conidia in the biopesticide formulation require an adjuvant to protect them from photoinactivation by sunlight. The suitability of Tinopal, an optical brightener used as sunscreen for baculovirus formulations, for use with B. bassiana was assessed. The aim was to study the effect of Tinopal on the growth and photoprotection of B. bassiana, and its effect on the susceptibility of insects to B. bassiana. RESULTS: Tinopal was found to have no adverse effect on the growth of B. bassiana. It was found to confer total protection (approximately 95% conidial germination at 10 g Tinopal L(-1)) from sunlight up to 3 h of exposure, and a better survival rate than controls even up to 4 h. Helicoverpa armigera Hübner larvae fed on diet with 5 g kg(-1) Tinopal were found to have reduced growth. The duration of the larval stage increased by 3-4 days in 1 and 5 g kg(-1) Tinopal treatments. Among the moths that emerged from larvae fed on diet with 5 g kg(-1) Tinopal, a significantly high number were malformed compared with controls. The larvae that were fed diet with Tinopal showed quicker and higher mortality and required a lower effective lethal dose (LC(50)) than the controls. Tinopal was found to have a synergistic effect with B. bassiana in causing insect mortality. CONCLUSIONS: Tinopal was found to be a suitable adjuvant for B. bassiana-based biopesticide formulations. It conferred tolerance to sunlight and caused stress in the insect, leading to a synergistic effect with B. bassiana.  相似文献   
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