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241.
The present study revealed the role of earthworm in converting tannery sludge into a valuable product. Tannery sludge was toxic to earthworm, therefore it was mixed with cattle dung in different proportions viz. 0:100 (T0), 10:90 (T10), 25:75 (T25), 50:50 (T50) and 75:25 (T75) on dry weight basis. The minimum mortality and highest population buildup of worms was in T0 mixture. Nitrogen, sodium, phosphorus and pH increased from initial in the range of 7.3-66.6%, 16.90-70.58%, 8.57-44.8% and 2.8-13.65%, respectively. On the other hand potassium, organic carbon and electrical conductivity decreased in the range of 4.34-28.5%, 7.54-22.35% and 32.35-53.12%, respectively. C:N ratio decreased from 20.53% to 47.36% in the final products. Transition metals increased significantly from the initial value and within the permissible limit. The result indicated that vermicomposting with Eisenia fetida is better for changing this sludge into nutrient rich manure in a short period of time. 相似文献
242.
The present study determines the prevalence, economic impact of virulent footrot in central Kashmir, India, along with isolation and molecular characterization of Dichelobacter nodosus (D. nodosus) where so far no such work has been carried out. Over all 12.54% prevalence of footrot was recorded in central Kashmir with highest (15.84%) in district Srinagar, and least (10.89%) in district Budgam, while it was 13.28% in district Ganderbal. Overall economic impact of footrot was estimated to the tune of Rs 15.82 million annually to the sheep farming in central Kashmir. Out of 370 samples collected from footrot lesions of naturally infected sheep, 200 (54.05%) detected D. nodosus positive by polymerase chain reaction (PCR). Out of these, 132 (66.00%) samples carried serogroup B of D. nodosus, five (2.50%) serogroup E, one (0.50%) serogroup I, while, 53 (26.50%) had mixed infection of serogroups B and E, four (2.00%) of serogroups B and I, two (1.00%) of serogroups B and G and the remaining three (1.50%) samples harboured the mixed infection of serogroups B, E and I. Serogroup G was detected for the first time in India. Over all serogroup B was most frequent (97.0%) followed by E (30.5%), while serogoups I (4.0%) and G (1.0%) were least prevalent. A total of 265 D.nodosus strains were isolated out of which 194 (73.20%) were typed as serogroup B, 61 (23.01%) as serogroup E, eight (3.01%) as serogroup I and remaining two (0.75%) belonged to serogroup G. Out of 265 D. nodosus isolates, 164 (61.88%) possessed intA (integrase) gene, thus were considered as virulent strains. Serogroup wise intA gene was found in 121(62.37%) isolates of serogroup B, 36 (59.01%) of E, two (100%) of G and five (62.50%) of I. Out of 20 randomly selected isolates subjected to gelatin gel test, 16 isolates with intA gene produced thermostable protease while four isolates without intA gene revealed the production of thermolabile protease. This indicated a good co-relation between presence of intA gene and gelatin gel test in determination of the D. nodosus virulence. Thus the present investigation suggests the incorporation of serogroups B and E, based on their predominant prevalence, in the formulation of an effective bivalent vaccine to combat footrot in central Kashmir. 相似文献
243.
Athar Ali Ganie Mohmad Farooq Azam Abdul Hamid Wani 《Archives Of Phytopathology And Plant Protection》2013,46(13):1582-1585
A new coelomycetous fungus Exosporodiella phoenixesa gen. et spec, nov., has been described and illustrated from the leaves of Phoenix from India. 相似文献
244.
Solid waste management is a worldwide problem and it is becoming more and more complicated day by day due to rise in population, industrialization and changes in our life style. Transformation of industrial sludges into vermicompost is of double interest: on the one hand, a waste is converted into value added product, and, on the other, it controls a pollutant that is a consequence of increasing industrialization. Garden waste, kitchen waste and cow dung were subjected to recycle through vermicomposting by using the epigeic earthworm Eisenia fetida under field conditions. The pH, moisture content, total organic carbon, humus, nitrogen, phosphorous and potassium in vermicompost was analysed. It was found that moisture content, total organic carbon, humus, nitrogen, phosphorous and potassium was high in cow dung, followed by kitchen waste and garden waste. This study clearly indicates that vermicomposting of garden waste, kitchen waste and cow dung can not only produce a value added produce (vermicomposting) but at the same time reduce the quantity of waste. 相似文献
245.
以同域分布于新疆南部的早春开花植物短穗柽柳(Tamarix laxa Willd)和紫杆柽柳(T.androssowii Litw)为材料,对它们的开花式样、花部特征、花报酬特点、传粉特性及交配方式进行比较研究。结果表明,2种植物居群和个体水平的花期及单花寿命间存在显著差异;紫杆柽柳的居群花期比短穗柽柳短,而短穗柽柳个体花期和单花寿命比紫杆柽柳长。2种柽柳的花瓣、雌雄蕊长度、花粉胚珠数及花粉/胚珠比值(P/O)间也存在显著差异。二者的花瓣、雌雄蕊均能分泌香味,访花频率与花蜜量均存在正相关。主要传粉者在短穗柽柳上的访花频率和沉积花粉效率高于紫杆柽柳,且存在显著差异。2种植物通过自花和异花授粉均可结实,属于混合交配系统;二者的自交不亲和指数及花粉限制程度间存在显著差异;紫杆柽柳的自交亲和性高于短穗柽柳,而短穗柽柳的花粉限制指数高于紫杆柽柳。因此,2种柽柳的开花式样、花部特征及花报酬的差异,是它们在传粉者受限的早春环境中为吸引更多的访花昆虫、提高雌性繁殖率所形成的繁殖对策。 相似文献
246.
Gowher A. Wani Manzoor A. Shah Zafar A. Reshi Mudasir A. Dar 《Acta Physiologiae Plantarum》2018,40(3):58
Invasive species pose a major threat to native biodiversity and ecosystem integrity in many ecologically sensitive parts of the globe. Many research efforts have so far been made mainly with a focus on morphology, physiology and reproductive biology of invasive species to explain what determines the patterns of invasion. Recently, polyploidy has been reported to significantly influence plant invasiveness. Notwithstanding the profound management and conservation implications, determining the genetic basis of plant invasiveness is a challenging task for ecologists. Variation in ploidy levels of species promises to yield some useful insights in this direction and we, therefore, aimed to test the relation between polyploidy and species invasiveness. We documented chromosome number and ploidy level of 118 alien aquatic plant species including 50 alien non-invasive and 70 alien invasive species, belonging to 64 genera and 39 families distributed across various aquatic habitats of the Kashmir Himalaya at different stages of invasion. Results yielded 47 (39.83%) diploid species, 53 (44.91%) polyploids and the remaining 18 (15.25%) species were reported to have mixed ploidy, i.e., both diploids and polyploids. The invasive plant species exhibited about 40% of intraspecific ploidy polymorphism in contrast to about 28% found in non-invasive plant species. Alien invasive species (at stage IVa, IVb and V senso Colautti and MacIsaac 2004) were found to have more polyploidy (60%) than non-invasive species (at stage II and III) having only 45.23% polyploidy. Our results depict a clear pattern that non-invasive species are disproportionately more diploids with lower ploidy ratios, while invasive plant species on the contrary exhibit higher chromosome counts, thereby being predominantly polyploids. Invasion stage III with 17 diploid species represents by far the highest relative proportion of diploid species, while invasion stage V having 16 polyploid species is highest in terms of polyploid species. Regression analysis based on the stage of invasion and the ploidy status revealed that the relative proportion of polyploids on progressing stage of invasion increases significantly (p < 0.01). These results indicate that polyploidy may be one of the potential determinants of plant invasion. The implications of these results in timely prediction and better management of invasive species are discussed. 相似文献
247.
Species‐specific germination responses to fire‐associated heat of elephant‐dispersed seeds in Nimule National Park,South Sudan
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Fire‐related heat and endozoochory by elephants have independently been found to be important for savanna plant seed germination, yet there is little information on how heat affects germination of elephant‐dispersed seeds. We measured the germination behavior (time to germination and proportion of seeds germinating) of 11 species of seeds extracted from African savanna elephant dung and subjected them to various intensities of heat as a proxy for fire exposure. The effects of heat were inconsistent and varied significantly by species, with some species having increased time to germination in response to heat and others having reduced time to germination. More studies are needed to expand the number of seed species examined and tease apart the interaction between elephant‐mediated endozoochory and fire. 相似文献
248.
Tanvi V. Wani Silvia Bua Pravin S. Khude Abdul H. Chowdhary 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):962-971
A series of novel sulphonamide derivatives was obtained from sulphanilamide which was N4-alkylated with ethyl bromoacetate followed by reaction with hydrazine hydrate. The hydrazide obtained was further reacted with various aromatic aldehydes. The novel sulphonamides were characterised by infrared, mass spectrometry, 1H- and 13C-NMR and purity was determined by high-performance liquid chromatography (HPLC). Human (h) carbonic anhydrase (CA, EC 4.2.1.1) isoforms hCA I and II and Mycobacterium tuberculosis β-CA encoded by the gene Rv3273 (mtCA 3) inhibition activity was investigated with the synthesised compounds which showed promising inhibition. The KIs were in the range of 54.6?nM–1.8?µM against hCA I, in the range of 32.1?nM–5.5?µM against hCA II and of 127?nM–2.12?µM against mtCA 3. 相似文献
249.
Gulzar Khan Mariana O. Godoy Fernando F. Franco Manolo F. Perez Nigel P. Taylor Daniela C. Zappi 《分类学与生物多样性》2018,16(2):188-199
In allopatric systems, where gene flow is highly constrained, the distinction between intraspecific differentiation and speciation is a challenging task. Pilosocereus jauruensis is a columnar cactus restricted to patchy dry habitats of Pantanal, Cerrado, and Chaco biomes in south-western Brazil and neighbouring countries. This species was recently reinstated after having been synonymized with P. machriisi, now including P. paraguayensis, P. saudadensis, and P. densivillosus as its synonyms. These taxa have been placed within the informal Aurisetus group. The present study aimed to investigate the genetic structure of P. jauruensis in order to identify possible distinct evolutionary lineages, and to support further refinement of the taxonomy of this species. For this purpose, 10 microsatellite loci were genotyped for 156 individuals of P. jauruensis. To provide a proxy for the expected interspecific differentiation level within this allopatric system, two populations (49 individuals) of P. vilaboensis (a species closely related to P. jauruensis) were also included. Additionally, two cpDNA markers (trnSGCU-trnGUCC and trnT-trnL) for a subsample of 44 individuals of both species were sequenced. The results obtained showed that even though P. jauruensis populations are relatively small and isolated, they still maintain a high level of genetic diversity (e.g., HE = 0.557 to 0.725; HO = 0.253 to 0.409). The study suggests the existence of two distinct taxa/evolutionary lineages through their entire distribution. Two populations found in the same geographic region of the now synonymized P. densivillosus showed significant genetic divergence when compared with other populations of P. jauruensis. In contrast, our results did not support an evolutionary independence hypothesis for populations that occur in the same geographic region of the synonymous P. saudadensis. 相似文献
250.
Apple (Malus × domestica) is the third important fruit in terms of production and consumption worldwide. Apple scab caused by Venturia inaequalis is the most devastating disease of apple. In the apple-growing regions, many fungicides are sprayed to control the disease leading to increase in the production cost. Development of scab-resistant cultivars is the long-lasting solution to control the disease. In apples, more than 20 major scab resistance genes have been identified in various cultivars and few wild relatives. Of all these genes, Rvi6 derived from Malus floribunda has been most extensively used in different breeding programs. Gene for gene interactions of these resistance genes with the avirulence genes from V. inaequalis have been understood in many cases. QTL-based polygenic resistance has also been characterized in apple. Nucleotide Binding Site Leucine-Rich Repeats (NBS-LRR) have been identified from the apple genome and many of them have been characterized from the scab resistance region. Molecular markers associated with most of the major scab resistance genes have been identified and their position has been mapped on different linkage groups. Marker-assisted selection (MAS) can be helpful in speeding up and accurately identifying the scab-resistant parents and progeny. Pyramiding of several major resistance genes can be undertaken for more durable resistance against apple scab. The present paper reviews the Malus-Venturia pathosystem, current status of knowledge about scab resistance genes, and their application in breeding against apple scab. 相似文献