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1.
A field experiment was conducted to study the effect of planting material and plant density on stevia (Stevia rebaudiana Bertoni) under western Himalayan conditions during 2011 and 2012. The experiment conducted in a split plot design consisted of two types of planting material (rooted slips and fresh seedlings) in the main plot and five inter- and intra-row spacing in subplots with three replications. Yield attributes and dry leaf biomass yield of stevia were not affected by the type of planting material; however, plant density significantly influenced the yield attributes and leaf and stem dry biomass. Although the wider spacing (60 × 45 cm) gave more leaves, higher leaf area index, higher leaf dry mass per plant as compared to closer spacing, it resulted in lower values of these attributes per unit area. Plants spaced in 30 × 30 cm accumulated 41.2% and 42.8% more total biomass than 60 × 45 cm. Steviol glycoside content did not change due to different planting materials and plant densities; however, closer plant spacing (30 × 30 cm) recorded 114.8% and 70.0% higher steviol glycoside accumulation compared to wider row spacing (60 × 45 cm) in 2011 and 2012, respectively. 相似文献
2.
Fruits of Pyracantha crenulata were collected from two locations varying by approximately 550 m in elevation from south aspect for assessing seed maturation
indicators. The mean seed size (length×diameter) across the collection dates varied between 1.61 ± 0.7 and 4.93 ± 0.06 mm2 across both the locations. The seed moisture content negatively correlated with germination. The change in fruit colour from
dark green to light orange, the range of fruit moisture content (30.43% ± 0.06 to 36.10% ± 0.25) and the seed moisture content
between 68.8% ± 0.68 and 71.6 ± 0.62 coincided with maximum germination and appear to be major indicators of seed maturation
in Pyracantha crenulata. 相似文献
3.
Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants
Background
Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganoderma sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed.Results
Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO3 (1.0), and MgSO4 (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained.Conclusions
The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods. 相似文献4.
Swati Walia 《Communications in Soil Science and Plant Analysis》2017,48(1):83-91
Leaf area (LA) is an important parameter related to plant growth and physiology. An allometric model was developed to estimate the LA of endangered medicinal plant Valeriana jatamansi using linear measurements such as leaf length (L) and width (W). LA and other leaf dimensions were measured using a laser leaf area meter. Leaves from seven accessions of valeriana were collected from the experimental site during 2015. Different regression models were developed between LA and other leaf components, viz. L, W, etc. The linear model having LW as an independent variable (y = 0.487 + 0.644 LW) provided the best estimation [coefficients of determination (R2) = 0.974, root mean square error (RMSE) = 2.222, coefficient of variation (CV) = 4.529]. Validation of the selected model showed a higher correlation between the actual leaf area (ALA) and the predicted leaf area (PLA) [R2 = 0.956, RMSE = 2.310, CV = 5.319, predicted residual error sum of squares (PRESS) = 1067.352]. 相似文献
5.
Diacetyl (DA), a natural butter flavorant, is a causative agent for the lung disease obliterative bronchiolitis. Mutagenic properties of 1,2-dicarbonyls have previously been empirically linked to their possible interaction with DNA nucleobases. This study for the first time identifies chemically the adduct of DA with 2-deoxyguanosine. Selective reactivity of DA with 5'-TTTGTTTTT-3' over 5'-TTTTTTTTT-3' indicated its propensity to modify specifically the guanosine residue. Treatment of plasmid DNA, pBR322, with DA induced changes in electrophoretic mobility that are typical of ternary structure disruption. Such DNA nucleobase interaction of DA translated into increased apoptosis in DA-treated SH-SY5Y cells in a dose-dependent manner (IC(50) = 0.114 ± 0.0421 mM). The traditional carbonyl scavengers metformin, 2-thiobarbituric acid, and d-penicillamine protected cells from DA toxicity in proportion to their rates of reaction with DA, with d-penicillamine causing a maximal increase in the IC(50) to 5.23 ± 0.0992 mM when co-incubated with DA. 相似文献
6.
The interactive effects of moisture and organic amendments (farmyard manure (FYM), crop residue (CR) and green manure (GM) (Sesbania aculeata) on gaseous carbon (C) emission, soil labile C fractions, enzymatic activities and microbial diversity in tropical, flooded rice soil were investigated. The amendments were applied on equal C basis in two moisture regimes, that is, aerobic and submergence conditions. The CO2 production was significantly higher by 22% in aerobic than in submergence condition; on the contrary, the CH4 production was 27% higher under submergence condition. The labile C fractions were significantly higher in GM by 26% under aerobic and 30% under submergence conditions, respectively, than control (without any kind of fertilizer or amendments). Eubacterial diversity identified by PCR-DGGE method (polymerase chain reaction coupled with denaturant gradient gel electrophoresis) was higher under GM followed by FYM, CR, and control and it is pronounced in submerged condition. GM favored the labile C accumulation and biological activities under both submergence and aerobic conditions, which makes it most active for soil–plant interactions compared to other organic amendments. Considering environmental sustainability, the use of GM is the better adoptable option, which could enhance labile C pools, microbial diversities in soil and keep soil biologically more active. 相似文献
7.
Biodiversity persistence in non-woody tropical farmlands is poorly explored, and multi-species assessments with robust landscape-scale
designs are sparse. Modeled species occupancy in agricultural mosaics is affected by multiple factors including survey methods
(convenience-based versus systematic), landscape-scale agriculture-related variables, and extent of remnant habitat. Changes
in seasonal crops can additionally alter landscape and habitat conditions thereby influencing species occupancy. We investigated
how these factors affect modeled occupancy of 56 resident bird species using a landscape-scale multi-season occupancy framework
across 24 intensively cultivated and human-dominated districts in Uttar Pradesh state, north India. Convenience-based roadside
observations provided considerable differences in occupancy estimates and associations with remnant habitat and intensity
of cultivation relative to systematic transect counts, and appeared to bias results to roadside conditions. Modeled occupancy
of only open-area species improved with increasing intensity of cultivation, while remnant habitat improved modeled occupancy
of scrubland, wetland and woodland species. Strong seasonal differences in occupancy were apparent for most species across
all habitat guilds. Further habitat loss will be most detrimental to resident scrubland, wetland and woodland species. Uttar
Pradesh’s agricultural landscape has a high conservation value, but will require a landscape-level approach to maintain the
observed high species richness. Obtaining ecological information from unexplored landscapes using robust landscape-scale surveys
offers substantial advantages to understand factors affecting species occupancy, and is necessary for efficient conservation
planning. 相似文献
8.
Genetic diversity of oilseed Brassica napus inbred lines based on sequence-related amplified polymorphism and its relation to hybrid performance 总被引:38,自引:0,他引:38
Significant heterosis for seed yield in oilseed rape has created interest in the development of hybrid cultivars. The DNA‐based marker protocol, sequence‐related amplified polymorphism (SRAP) was used to determine genetic diversity among oilseed rape maintainer and restorer lines. This measure was used in an attempt to establish an association between genetic distance and heterosis in hybrids for various agronomic traits. A total of 118 polymorphic loci were generated by 18 SRAP primer combinations. Based on the polymorphism generated by the markers, calculated similarity index values ranged from 0.46 to 0.97. Cluster analysis grouped 10 maintainer and 12 restorer lines into three groups, with the exception of two maintainer lines, PM5 and PM9, which fell outside these groups. The grouping of the lines was largely in agreement with the available pedigree data on their origin and agronomic performance. Analysis of variance among inbred lines and their resulting F1 hybrids over two locations revealed significant differences for plant height, days to maturity and seed yield, but not for oil content. Substantial mid‐parent heterosis was observed only for seed yield, and ranged from 26% to 169%. All hybrids surpassed their respective inbred lines for this trait, except for a single cross combination of related lines. In general, crosses of lines located in different clusters yielded more than those from the same clusters. Regression analysis revealed a statistically significant relationship between the genetic distance of the parents and seed yield in their hybrid, and their derived mid‐parent and high‐parent heterosis. The correlation coefficient between genetic distance and yield (0.64) indicated a moderately strong relationship, so it is possible that some of the SRAP markers might be linked to quantitative trait loci for seed yield. 相似文献
9.
Pramod Marru Vaibhav Latane C. Puja K. Vikas Pushpendra Kumar Swati Neogi 《Fibers and Polymers》2014,15(9):1935-1940
Accelerated ageing test methodology is valid and widely accepted procedure for estimating the lifetime of isotropic homogeneous polymeric materials. However for non-isotropic and heterogeneous polymeric compounds such as glass reinforced epoxy (GRE) pipes, accelerated ageing test methodology has not been much investigated. Various standards such as ASTM D 3681, ASTM D 5365 are being used to estimate the lifetime of GRE pipes using regression analysis which is time consuming, and requires large number of test specimens and fixtures specific to pipe dimensions. Accelerated ageing test methodology can be a viable method for estimating the lifetime. The research on accelerated test methodology as a vital tool to determine the lifetime of GRE pipes has been limited. The major concern for using accelerated ageing test methodology is primarily due to the degradation kinetics of the anisotropic composite materials which may not be governed by the Arrhenius principle. The present study on the estimation of lifetime of GRE pipes in extreme acidic and alkaline medium reveals that degradation of the composite pipe follows the Arrhenius principle and the degradation mechanism can be described by first order reaction kinetics. The degradation rate, the temperature dependence of the degradation rate and lifetime of the glass reinforced epoxy pipes in extreme acidic and alkaline medium as found in the current study are presented here, along with the morphological study of aged and un-aged GRE pipes. 相似文献
10.
The innate immune system of fish is considered first line of defense against a broad spectrum of pathogens. Being a component of innate immunity and lying at the interface between fish and the aqueous environment, skin mucus plays a frontier role in protecting fish from infections. In the present study, skin mucus of Cirrhinus mrigala, Labeo rohita, Catla catla, Rita rita and Channa punctata, inhabiting different ecological niches, was analyzed to characterize potential innate immune factors such as lysozyme, proteases, phosphatases, esterase and sialic acid. The enzyme activities were high in bottom dweller species, C. punctata and C. mrigala, and low in clean water inhabiting species, L. rohita and C. catla. An inverse relationship was observed between the level of enzyme activity and the sialic acid content in these fish species. In R. rita, however, the levels of all factors were found to be low. Zymographic analysis with labeled Micrococcus lysodeikticus revealed three isoforms of lysozyme in C. punctata and two in each species, C. mrigala, L. rohita and C. catla. In R. rita, lysozyme could not be detected. Gelatin zymography revealed that serine and metalloproteases were the major mucus proteases in all fish species investigated. In addition, trypsin-like protease and Ca(++)-specific serine proteases were observed in skin mucus. Increased knowledge of these parameters could be useful in understanding the role of skin mucus in the innate immune system of fish species inhabiting different ecological niches. 相似文献