The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat metho...The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat method during April 2002 to November 2002. Totally 100 plots of 3 m X 3 m in size represents a total of 64 regenerating tree species from natural forest with an average seedlings of 24767/hm2, while only 40 regenerating tree species were recorded from enrichment plan-tations with an average seedlings of 18633/hm2. Maximum regeneration in natural forest was found with Castanopsis spp. (2200 seedlings/hm2) followed by Glochidion lanceolarium (2183 /hm2) whereas, in enrichment plantations maximum regen-eration was found with Dipterocarpus gracilis (2117/hm2) followed by Anogeissus acuminata (2000/hm2). For natural forest, highest relative density was found for Castanopsis spp (8.88%), relative frequency for Glochidion lanceolarium (7.36%), rela-tive abundance for Syzygium spp. (3.79%) and Importance Value Index were recorded with Glochidion lanceolarium (18.24%). The corresponding values for enrichment plantations were highest with Dipterocarpus gracilis (11.36%), Glochidion lanceo-larium (9.71%), Dipterocarpus gracilis (5.92%), Glochidion lanceolarium (23.32%) respectively. Stem per hectare of some common trees with their seedlings and saplings in both the natural stands and enrichment plantations showed that only Dip-terocarpus gracilis successfully recruited in both sites but recruitment was higher in natural forest. Like many other primary rain forests, the Baraitoli forest typically has both substantial seedlings and soil seed bank from which regeneration may occur. The naturally regenerated seedlings are quite dense but it could not reach the pole stage due to human interference.展开更多
In recent years, the world has faced rising global temperatures, accumulative pollution, and energy crises, stimulating scientists worldwide to strive for eco-friendly and cost-effective solutions. Biochar has materia...In recent years, the world has faced rising global temperatures, accumulative pollution, and energy crises, stimulating scientists worldwide to strive for eco-friendly and cost-effective solutions. Biochar has materialized as a favorable tool for environmental remediation, indicating efficacy as an efficient sorbent substance for both inorganic and organic pollutants in environmental field. These unique properties exclude improved surface functionality, porous morphology, large specific surface area (SSA), cation exchange capacity (CEC), robust adsorption capabilities, environmental stability, and embedded micronutrients. Biochar exhibited potential characteristics for environmental oversight, greenhouse gas (GHG) emission reduction, and soil fertility improvement. This review explores the impact of fundamental factors such as retention time, pyrolysis temperature, gas flow rate, and reactor design on biochar yield and properties. Collected data revealed the various applications of biochar, ranging from waste management and construction materials to the adsorptive removal of hydrocarbon lubricants from aqueous media, contaminant immobilization, and carbon sequestration. It has played mostly a significant share in climate change mitigation and an important role in soil amendments. Biochar improves soil improvement by increasing water retention (10%–30%), carbon sequestration, soil surface functionality, and providing high surface area with chemical stability. The assessment also reports the prospects and contests associated with biochar application uses in various agriculture cropping ecosystems. Inclusive, this review highlights the multifaceted characteristics of biochar as an adjustable on top of a sustainable solution addressing greenhouse gas emission, carbon sequestration, and environmental stresses. However, further research is needed to understand its long-term impacts and optimal applications fully.展开更多
The practice of conservation tillage or straw return to the farmland influences the grain yield and quality of rice(Oryza sativa).The key volatile compound responsible for the fragrance of fragrant rice is 2-acetyl-1-...The practice of conservation tillage or straw return to the farmland influences the grain yield and quality of rice(Oryza sativa).The key volatile compound responsible for the fragrance of fragrant rice is 2-acetyl-1-pyrroline(2-AP),which is significantly affected by field management measures.The purpose of this study was to investigate the impact of tillage management and straw return on the grain yield and biosynthesis of 2-AP in fragrant rice.This study was conducted over two years in 2016 and 2017 and used two fragrant rice cultivars(Meixiangzhan 2 and Xiangyaxiangzhan)as materials.The experimental design consisted of different tillage management and straw return treatments,which included three tillage management regimes:rotary tillage(T0),minimum tillage(T1),and no tillage(T2);and two straw return treatments:without straw return(S0)and straw return(S1).The straw used for the experiment was sourced from the residue of the corresponding fragrant rice cultivar harvested in the early season.Tillage management and straw return substantially affected the grain yields,grain quality,and 2-AP contents of both fragrant rice cultivars.Compared with the T0S0 treatment,tillage management and straw return resulted in 2-AP content improvements in 2016(12.41–116.85%)and 2017(34.85–103.89%)on average.Higher 2-AP contents were also detected in both fragrant rice cultivars in the T2S1 and T1S1 treatments.A structural equation model(SEM)demonstrated that the activities of enzymes related to fragrance metabolism in the leaves and grain jointly regulated the biosynthesis of precursors of fragrance metabolism in the grain,which further promoted the accumulation of 2-AP.In addition,a principal component analysis indicated that the T1S1 treatment was positively correlated with both 2-AP and grain yield.The SEM demonstrated that the enzymes related to nitrogen metabolism,parameters related to photosynthesis,and yield components contributed to the grain yield.The T1S1 treatment resulted in the highest average grain yield of 760.75 g m^(-2),which could be attributed to increases in various attributes,such as the leaf area index,SPAD value,nitrogen metabolism,panicle number m^(-2),and grain number per panicle.In summary,the minimum tillage and straw return(T1S1)treatment is more effective at simultaneously improving both the grain yield and 2-AP content in fragrant rice.展开更多
We studied the genetic polymorphism among 29 clones of shisham （Dalbergia sissoo Roxb） belonging to different geographic regions using random amplified polymorphic DNA （RAPD） markers. Out of 30 primers used, only ...We studied the genetic polymorphism among 29 clones of shisham （Dalbergia sissoo Roxb） belonging to different geographic regions using random amplified polymorphic DNA （RAPD） markers. Out of 30 primers used, only 20 primers generated polymorphism in amplified product. In total 232 bands were amplified with 20 primers, of which 192 （82%） were polymorphic with an average of 9.6 bands/primer. The resolving power （Rp） ranged from 2.14 （Primer 5） to 11.93 （Primer 4）. Primer 4 and Primer 3 possessed high Rp value. Polymorphism information content （PIC） ranged from 0.15 （Primer 5） to 0.37 （Primer 4）. Primer 4 amplified total 18 bands in 29 genotypes with PIC value of 0.37 hence; this set of primer was most informative. The similarity coefficient analysis revealed two clusters. The first cluster comprised of only 10 clones and the second major cluster comprised of 19 clones. The genetic similarity among 29 clones ranged from 25.86% （clone 10 and 235） to 100% （clone 19 and 59）, suggesting a wide genetic base in shisham clones.展开更多
Objective: Bergenia ciliata(Haw.) Sternb. is used in the Indian traditional system of medicine to treat various ailments including rheumatism and to heal wounds. The objective of the present study was to perform a pre...Objective: Bergenia ciliata(Haw.) Sternb. is used in the Indian traditional system of medicine to treat various ailments including rheumatism and to heal wounds. The objective of the present study was to perform a preclinical characterization of the B. ciliata-based botanical extract IIIM-160.Methods: ⅢM-160 was chemically standardized and analyzed for heavy metal content, aflatoxins,pesticides and microbial load. The in vitro and in vivo efficacies were determined in suitable models of inflammation, arthritis and nociception. An acute oral toxicity study was performed in Swiss albino mice.A suitable oral formulation was developed and characterized.Results: Bergenin was found to be the major component(9.1% w/w) of ⅢM-160. The botanical lead displayed inhibition of lipopolysaccharide-induced production of proinflammatory cytokines in THP-1 cells, with selectivity toward interleukin-6(IL-6) and had an excellent safety-window. It showed anti-inflammatory, anti-arthritic and antinociceptive activity in animal models and was not toxic at oral doses up to 2 g/kg in Swiss-albino mice. The gastroretentive, sustained-release capsule formulation showed sustained-release of the bergenin over the period of 24 h, resulting in improved plasma-exposure of bergenin in Sprague–Dawley rats.Conclusion: The dual-activity of IL-6 inhibition and antinociception marks the suitability of ⅢM-160 for treating rheumatoid arthritis. This study will serve as the benchmark for further research on this botanical formulation.展开更多
At the seedling stage, a small amount of N is required to boost growth of leguminous plants. A pot experiment was conducted to observe the effect of N fertilizer on various growth parameters and nodulation behavior of...At the seedling stage, a small amount of N is required to boost growth of leguminous plants. A pot experiment was conducted to observe the effect of N fertilizer on various growth parameters and nodulation behavior of Pongamia pinnata under nursery conditions. After the estab- lishment of seedlings, four nitrogen treatments, 0, 40, 80 and 100 kg-ha^-1 N were applied in two equal splits. Monthly observations were taken for the morphological parameters viz. plant height, collar diameter, leaf number, root length, root shoot ratio, nodule number and weight per plant. Maximum plant height was recorded after application of N at 40 kg.ha^-1. Seasonally, the difference in collar diameter in rainy season was signifi- cantly higher than in winter or summer. However, more leaves were produced per plant at N-40 and N-100 treatments in winter and rainy seasons. Higher root length was recorded in rainy season than in winter or summer. Root biomass was higher than for stems or leaves. Seasonal effects of N-80 and N-40 treatments on leaf dry weight were significantly higher than for N-100 or N-0. Stem dry weight was higher at N-40 than at other treatments in winter and summer seasons. Root：shoot ratio was higher throughout winter to early summer. Nodule biomass was 2-3 times higher in rainy season compared to winter or summer. Maximum nodule number and biomass per plant were highest at N-40, followed by N-0, N-80 and N-100 treatments. New nodule formation started from June to the end of September. Maximum biomass per plant was recorded at N-40, followed by N-80, N-100 and N-0. Nitrogen treatment effect and seasonal behaviour interaction were not significant. Significantly higher numbers of nodules per plant were recorded in rainy season followed by summer and winter for all treatments. Higher nitrogen doses suppressed growth while lower doses promoted growth in Pongamia pinnata. Therefore, the lower nitrogen dose i.e., N-40 Kg.ha^-1 applied in two equal splits was suitable at the initial nursery stage for the increase in nodula- tion and biomass production.展开更多
The performance and variability patterns in the wood element’s dimensions, specific gravity and growth parameters namely ramet height and GBH were evaluated in 16 clones of parents, F1 and F2 hybrids of Populus delto...The performance and variability patterns in the wood element’s dimensions, specific gravity and growth parameters namely ramet height and GBH were evaluated in 16 clones of parents, F1 and F2 hybrids of Populus deltoides Bartr. ex Marsh. Ramet radial variations were nonsignificant, while inter-clonal variations due to interaction of clone/replication were significant for all the wood traits except vessel element length. Inter-clonal variations were significant only for fiber length and fiber wall thickness. Fiber length and specific gravity were significantly higher in female, while wall thickness and vessel element length were higher in male clones. Female parents （G48 and S7C8） showed higher fiber length and specific gravity than of the male parent （G3）, while vessel diameter and wall thickness were higher in male par- ent （G3）. There is not much difference in fiber length and vessel element’s dimensions among the parents, F1 and F2 generation hybrid clones. Specific gravity did not showed any trend for parents, F1 and F2 generations. Generally female clones showed higher growth rate. Broad sense heritability for wood traits ranged from 0.143 （fiber length） to 0.505 （fiber wall thickness）, while for growth traits it was 0.374 （GBH） and 0.418 （height）. Genetic gain for all the wood and growth traits was positive for most of the wood traits. The highly divergent male clone （78） and female clones （S7C8, G48, W/A 49） in number of combinations could be used for developing new hybrids of desired wood traits to develop new clones.展开更多
To assess the effects of straw return coupled with deep nitrogen(N)fertilization on grain yield and N use efficiency(NUE)in mechanical pot-seedling transplanting(MPST)rice,the seedlings of two rice cultivars,i.e.,Yuxi...To assess the effects of straw return coupled with deep nitrogen(N)fertilization on grain yield and N use efficiency(NUE)in mechanical pot-seedling transplanting(MPST)rice,the seedlings of two rice cultivars,i.e.,Yuxiangyouzhan and Wufengyou 615 transplanted by MPST were applied with N fertilizer at 150 kg/hm2 and straw return at 6 t/hm2 in early seasons of 2019 and 2020.The experiment comprised of following treatments:CK(no fertilizer and no straw return),MDS(deep N fertilization and straw return),MBS(broadcasting fertilizer and straw return),MD(deep N fertilization without straw return),MB(broadcasting fertilizer without straw return).Results depicted that the MDS treatment significantly increased the rice yield by 41.69%-72.22%due to total above-ground biomass,leaf area index and photosynthesis increased by 54.70%-55.80%,38.52%-52.17%and 17.89%-28.40%,respectively,compared to the MB treatment.In addition,the MDS treatment enhanced the total N accumulation by 37.74%-43.69%,N recovery efficiency by 141.45%-164.65%,N agronomic efficiency by 121.76%-134.19%,nitrate reductase by 46.46%-60.86%and glutamine synthetase by 23.56%-31.02%,compared to the MB treatment.The average grain yield and NUE in both years for Yuxiangyouzhan were higher in the MDS treatment than in the MD treatment.Hence,deep N fertilization combined with straw return can be an innovative technique with improved grain yield and NUE in MPST in South China.展开更多
Berberis petiolaris Wall. ex G. Don, an unexplored medicinal plant belonging to the family Berberidaceae, is a large deciduous shrub found in Western Himalaya between 1800-3000 m. Chemical profiling of fruit, leaf, ro...Berberis petiolaris Wall. ex G. Don, an unexplored medicinal plant belonging to the family Berberidaceae, is a large deciduous shrub found in Western Himalaya between 1800-3000 m. Chemical profiling of fruit, leaf, root and stem was done by direct analysis in real time mass spectrometry followed by multivariate analysis for discrimination among the plant parts. The bioactive compounds, including magnofiorine, berberine, jatrorrhizine, thalifendine/berberrubine, demethyleneberberine, reticuline, 8-oxoberberine, N-methyltetrahydroberberine, tetrahydropalmatine, tetrahydroberberine and palmatine, were identified by their exact mass measurement and the corresponding molecular formula of each compound. A comparative study of distribution pattern for all these bioactive alkaloids showed qualitative and quantitative variations in different parts of B. petiolaris. Principal component analysis clearly dis- criminated each part of B. petiolaris plant.展开更多
Evaluation of thirty one core collections of Ocimum sanctum L. synonyms O. tenuiflorum L. collected from different ecological regions representing contrasting environment of India was carried out. All the collections ...Evaluation of thirty one core collections of Ocimum sanctum L. synonyms O. tenuiflorum L. collected from different ecological regions representing contrasting environment of India was carried out. All the collections were grown under sub-tropical region of Jammu, India. Study revealed wide range of variability in quantitive and qualitative attributes of oil. Essential oil content ranged between 0.16% ± 0.01% - 0.55% ± 0.08% showing the presence of fifteen constituents. Methyl eugenol (1.54% - 93.16%) and Eugenol (0.06% - 70.41%), were the major constituent. The other major constituent of the oil was β-Caryophyllene (4.60% - 33.77%) which was detected in almost all the collections. Borneol, Copane, α Caryophyllene were other constituents detected in almost all the accessions. α selinene was detected in traces in only three accessions (OS-01, OS-03, OS-50) and β-selinene was detected in four accessions (OS-01, OS-03, OS-50, OS-72. Accession OS-70 collected from Patna, showed distinct chemical profile having β-Elemene (32.81%), β-Cary- ophyllene (16.37%), Germacrene-D (18.05%), β-Ocimene (17.69%) and Copane (5.738%). Being distinct in oil profiling, Patna collection was designated as distinct chemotype. Collections OS-50 from Gwalior from Central India and OS-59 from Rajkot Western India have been identified as methyl eugenol (93.16%) and eugenol (70.41%) rich geno- types. The data collected provided useful information with respect to composition of essential oil among core collection evaluated representing various agro-climatic zones.展开更多
Plant growth hormone BAP (benzyl amino purine), KIN (kinetin), NAA (1-naphthalene acetic acid) and IBA (indole-3 butyric acid) effect was studied on in vitro multiplication of shoots and rooting of Drepanostachyum fal...Plant growth hormone BAP (benzyl amino purine), KIN (kinetin), NAA (1-naphthalene acetic acid) and IBA (indole-3 butyric acid) effect was studied on in vitro multiplication of shoots and rooting of Drepanostachyum falcatum. In vitro micropropagation of himalayan weeping bamboo is explained by in vitro shoot induction and proliferation. Excised explant with axillary bud is surface sterilized with 0.1% HgCl<sub>2</sub> for 10 - 12 minutes, cleaned with 90% ethanol and inoculated on liquid Murashige and Skoog (MS) culture medium supplemented with different concentrations of BAP/ KIN. Effect of BAP/KIN on shoot induction is with different rate and number of shoots produced by explants with axillary bud cultured on MS media supplemented with 0.0 mg/L BAP/KIN - 5.5 mg/L BAP/KIN. Shoot multiplication with highest rate is achieved on MS medium supplemented with 3.5 mg/L BAP after 4<sup>th</sup> sub-culturing. The most effective with highest rate and number of root induction combination is 6.5 mg/L IBA after 5 weeks. The roots produced by 6.5 mg/L IBA is best compared with other combination of auxin NAA (1-naphthalene acetic acid).展开更多
Deep placement of nitrogen fertilizer is a key strategy for improving nitrogen use efficiency. A two-year field experiment was conducted during the early rice growing seasons(March–July) of 2016 and 2017.The experime...Deep placement of nitrogen fertilizer is a key strategy for improving nitrogen use efficiency. A two-year field experiment was conducted during the early rice growing seasons(March–July) of 2016 and 2017.The experimental treatments comprised two rice cultivars: Wufengyou 615(WFY 615) and Yuxiangyouzhan(YXYZ), and three N treatments: mechanical deep placement of all fertilizers as basal dose at 10 cm soil depth(one-time deep-placement fertilization, namely OTDP fertilization);manual surface broadcast(the common farmer practice) of 40% N fertilizer at one day before sowing(basal fertilizer)followed by broadcast application of 30% each at tillering and panicle initiation stages;and no fertilizer application at any growth stage as a control. One-time deep-placement fertilization increased grain yield of both rice cultivars by 11.8%–19.6%, total nitrogen accumulation by 10.3%–13.1%, nitrogen grain production efficiency by 29.7%–31.5%, nitrogen harvest index by 27.8%–30.0%, nitrogen agronomic efficiency by 71.3%–77.2%, and nitrogen recovery efficiency by 42.4%–56.7% for both rice cultivars, compared with the multiple-broadcast treatment. One-time deep-placement fertilization reduced CH4-induced global warming potential(GWP) by 20.7%–25.3%, N2O-induced GWP by 7.2%–12.3%, and total GWP by 14.7%–22.9% for both rice cultivars relative to the multiple-broadcast treatment. The activities of glutamine synthetase and nitrate reductase were increased at both panicle-initiation and heading stages in both rice cultivars following one-time deep-placement fertilization treatment. Larger leaf area index at heading stage and more favorable root morphological traits expressed as larger total root length, mean root diameter, and total root volume per hill were also observed. One-time deep-placement fertilization could be an effective strategy for increasing grain yield and nitrogen use efficiency and lowering greenhouse-gas emissions under mechanical direct-seeded cropping systems.展开更多
To understand the effect of climate change on constitutive antioxidant and biochemical metabolites in Western Himalayas, five medicinal herbs were selected and grown at two altitudes in Jammu(305 m) and Srinagar(1730 ...To understand the effect of climate change on constitutive antioxidant and biochemical metabolites in Western Himalayas, five medicinal herbs were selected and grown at two altitudes in Jammu(305 m) and Srinagar(1730 m) with subtropical and temperate climates, respectively.Significant variations were observed in phenols and flavonoids in Hypericum perforatum L., Matricaria chamomilla L., Thymus vulgaris L., Cynara cardunculus L. and Echinacea purpurea L. growing at two locations. High altitude temperate site show variable(up to 13 fold) increase in their content.Proteins(1.3- 1.8 times), sugars(2.8- 4.1 times) and free amino acid(1.04- 1.22 times) were also higher at Srinagar(1730 m). Within these plants, H.perforatum and M. chamomilla have shown higher accumulation of phenols, xanthophylls and proline even at subtropical environment in Jammu(305 m)suggesting potential for increasing their geographical area. The results demonstrate that changing environmental conditions significantly affect the bioactive constituents, which accumulate as a defence strategy by these temperate plants. Their medicinal significance during climate change scenario has also been discussed.展开更多
Chrysopogon serrulatus(false beard-grass)is a dominant component of vegetation in the foothills of the Himalayas.To study whole plant morphology,individuals of C.serrulatus were collected from three plots at each of s...Chrysopogon serrulatus(false beard-grass)is a dominant component of vegetation in the foothills of the Himalayas.To study whole plant morphology,individuals of C.serrulatus were collected from three plots at each of six locations spanning from 400 to 1,400 m.The population colonizing the highest elevation modifications in different plant organs.Roots showed increased metaxylem number and area.In the stem,especially outside of the vascular tissue,there was intensive sclerification indicative of increased xeromorphy as a survival strategy.At the highest elevation,leaves were wider;aerenchyma formation and increased sclerification were noted in the leaf sheath;and a greater proportion of storage parenchyma was observed in the leaf blade,all indicators of succulence.In contrast,leaves at lower elevations had xeric morphological features such as increased epidermal thickness,sclerification and more developed metaxylem area.In conclusion,shifting of morphological features in below-and above-ground plant parts of C.serrulatus were linked to shifts in environmental factors along this elevation gradient,thus enabling the successful distribution of this species along this elevation gradient.展开更多
Rhizobia were isolated from Albizia lebbek （L） Benth. seed- lings collected from six different places, tested against the nodulation test and inoculated into 45 day old Albizia lebbek seedlings in sterile soil mixtu...Rhizobia were isolated from Albizia lebbek （L） Benth. seed- lings collected from six different places, tested against the nodulation test and inoculated into 45 day old Albizia lebbek seedlings in sterile soil mixture under glass house conditions. After a period of two and three months, the plant samples were taken to study the influence of inoculation treatments on nitrogen fixation, assimilation, biomass production and nitrogen content in different plant parts. The seedlings inoculated with isolates III（1） and III（2） of Lalpani had the maximum nodular biomass,展开更多
We studied radial and inter-progeny variations in the dimen- sions of the wood elements and specific gravity of 21 half sib progenies of Populus deltoides Bartr. ex Marsh. The female parents of half sib progenies were...We studied radial and inter-progeny variations in the dimen- sions of the wood elements and specific gravity of 21 half sib progenies of Populus deltoides Bartr. ex Marsh. The female parents of half sib progenies were G48 and $7C13 clones. Variance ratio （F） test indicated that inter-progeny variations in the dimensions of wood elements and specific gravity were significant for all wood traits while variations were significant for radial location for specific gravity only. Hierarchical clus- ter analysis was done by Squared Euclidean Distance for all of 21 proge- nies considering six wood traits. 21 progenies were grouped into 4 clus- ters. Cluster 1 was the largest cluster with 11 progenies, whereas cluster 3 had only one progeny. Selected progenies in clusters 3 （progeny 155, male） and 4 （progeny 108, 196, both female） were highly divergent from the other progenies so they were used in combinations as parents of hybrids to develop new clones with desired characters. Progeny 155 showed higher growth, fiber dimensions, and specific gravity, thus, should be used for the development of new clones.展开更多
The study of genetic variability is a prerequisite for any tree improvement program. Screening of clones showing the effect of dominance in growth and tree form is essential to identify productive clones, matched to s...The study of genetic variability is a prerequisite for any tree improvement program. Screening of clones showing the effect of dominance in growth and tree form is essential to identify productive clones, matched to sites. Our study performed in a clonal seed orchard at Lacchiwala of India, represented by 31 clones of Dalbergia sissoo （Shisham） Roxb. from diverse locations revealed significant variability at the 0.1% level of significance in various morphological traits. At the age of 13 years, clone 196 （Gonda） revealed maximum height of 20.2 m and a girth at breast height of 74.2 cm. The five identified clones viz. 196, 198, 192, 123 and 235 were well adapted to the climatic conditions of this zone, hence survived well and showed good performance compared to other clones. Heritability estimates of 87%, 83% and 80% for height, crown width and crown length respectively coupled with high genetic gains indicated strong genetic control of these variables. A correlation matrix of various growth attributes revealed positive correlation among these attributes. On the basis of the entire set of growth variables, the clones were grouped into two major clusters with three subgroups.展开更多
Tea estates in Bangladesh are currently experiencing frequent waterlogging stress due to heavy rainfall or flooding under changing climate scenarios.The development of waterlogging-tolerant tea cultivars is,therefore,...Tea estates in Bangladesh are currently experiencing frequent waterlogging stress due to heavy rainfall or flooding under changing climate scenarios.The development of waterlogging-tolerant tea cultivars is,therefore,crucial for sustainable tea production with increased yield in waterlogging-affected areas.In this study,a total of two hundred tea genotypes were screened for waterlogging tolerance based on yield and quality potentials.Tea genotypes were raised at the nursery and evaluated with 13 traits at the seedling and mature stages.Descriptive and multivariate analysis of the recorded data of measured traits were performed for clustering the studied genotypes in relation to their yield and quality potential.The 200 tea genotypes were categorized into six clusters and the measured traits were classified into two groups.Cluster-5 comprised 46 closely related tea genotypes whereas other clusters-Cluster-1,2,3,4,and 6 contained 39,20,24,29,and 42 genotypes,respectively.PCA-biplot showed that the first two principal components(PC 1 and PC 2)cumulatively described 56.9%of total variations.From the genetic diversity analysis,the characteristics like green leaf yield(GLY),plucking points(PP),spreading of bush frame(SBF),plucking interval(PI),dormancy period(DR),black tea quality score(QSB),fermentation rate(SF)and number of pubescence(NP)exhibited high to moderate heritability,indicating to consider these traits as selection criteria for tea breeding program.The trait GLY showed a strong positive correlation with PP,and SBF and a negative association with PI and DR.The key quality trait,QSB had a positive correlation with SF and NP.Based on these studied descriptors,a total of 11 tea genotypes were selected,found potential for waterlogging tolerance,and can be considered for varietal improvement programs.展开更多
Forest vegetation of a protected area （Binsar Wildlife Sanctuary） in Kumaun region （west Himalaya） was analysed for structure, composition and representativeness across three different altitudinal belts, lower （1...Forest vegetation of a protected area （Binsar Wildlife Sanctuary） in Kumaun region （west Himalaya） was analysed for structure, composition and representativeness across three different altitudinal belts, lower （1,6oo-1,8oo m a.s.1.）, middle （1,900-2,100 m a.s.1.） and upper （2,200-2,400 m a.s.1.） during 2oo9-2011 using standard phytosociological methods. Four aspects （east, west, north and south） in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper （18 species）, and lowest at lower altitudinal belt （15 species）. The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts （p〈0.05） while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons （p〉0.05）. The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes vis-a-vis role of ＇New＇ and ＇Not regenerating＇ species need priority attention while initiating conservation activities in the sanctuary. This study calls for exploring other less explored Wildlife Sanctuaries in the Himalaya and across the world, to achieve overall biodiversity status in these protected areas and thus to justify their role in conserving biodiversity in the region.展开更多
Stripe rust, caused by Puccinia striiformis f. sp. tritici （Pst） is an important disease of wheat （Triticum aestivum） in Nepal, which is a part of the Himalayas stretching over the North of Nepal, India, Pakistan,...Stripe rust, caused by Puccinia striiformis f. sp. tritici （Pst） is an important disease of wheat （Triticum aestivum） in Nepal, which is a part of the Himalayas stretching over the North of Nepal, India, Pakistan, Bhutan and beyond. Wheat production plays a crucial role in food security of the marginal hill farmers of Nepal. Frequent epidemics of the rust have caused huge loss in farmer＇s field. Periodic monitoring during 1980-2008 showed that changes in virulence occurred during this period. The objective of this study was to evaluate Pst resistance and its effective genes in wheat genotypes. For this, trap nurseries, wheat stripe rust differentials, commercial cultivars and advanced breeding lines were tested under artificial epiphytotic and natural hot spots conditions during 2005 to 2010. Four genes （Yr5, Yr10, Yr15 and YrSp） consistently showed resistance to the prevailing races. The gene Yr9 and Yr27 in combinations with Yrl8 were found effective. Other lines with combination of minor genes were also found effective. The genotypes Amadina, Kukuna, Tukuru, Kakatsi and Buck Buck widely used in breeding program were resistant. The cultivation of varieties WK1204, Gautam, Gaura and Dhaulagiri have ensured genetic diversity for the rust resistance and slowed down frequent occurrence of epidemics. The findings of these studies could help in developing effective varietal resistance program in the sub-continent.展开更多
文摘The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat method during April 2002 to November 2002. Totally 100 plots of 3 m X 3 m in size represents a total of 64 regenerating tree species from natural forest with an average seedlings of 24767/hm2, while only 40 regenerating tree species were recorded from enrichment plan-tations with an average seedlings of 18633/hm2. Maximum regeneration in natural forest was found with Castanopsis spp. (2200 seedlings/hm2) followed by Glochidion lanceolarium (2183 /hm2) whereas, in enrichment plantations maximum regen-eration was found with Dipterocarpus gracilis (2117/hm2) followed by Anogeissus acuminata (2000/hm2). For natural forest, highest relative density was found for Castanopsis spp (8.88%), relative frequency for Glochidion lanceolarium (7.36%), rela-tive abundance for Syzygium spp. (3.79%) and Importance Value Index were recorded with Glochidion lanceolarium (18.24%). The corresponding values for enrichment plantations were highest with Dipterocarpus gracilis (11.36%), Glochidion lanceo-larium (9.71%), Dipterocarpus gracilis (5.92%), Glochidion lanceolarium (23.32%) respectively. Stem per hectare of some common trees with their seedlings and saplings in both the natural stands and enrichment plantations showed that only Dip-terocarpus gracilis successfully recruited in both sites but recruitment was higher in natural forest. Like many other primary rain forests, the Baraitoli forest typically has both substantial seedlings and soil seed bank from which regeneration may occur. The naturally regenerated seedlings are quite dense but it could not reach the pole stage due to human interference.
基金Deanship of Scientific Research(DSR)at King Faisal University,Saudi Arabia,under project number KFU241939.
文摘In recent years, the world has faced rising global temperatures, accumulative pollution, and energy crises, stimulating scientists worldwide to strive for eco-friendly and cost-effective solutions. Biochar has materialized as a favorable tool for environmental remediation, indicating efficacy as an efficient sorbent substance for both inorganic and organic pollutants in environmental field. These unique properties exclude improved surface functionality, porous morphology, large specific surface area (SSA), cation exchange capacity (CEC), robust adsorption capabilities, environmental stability, and embedded micronutrients. Biochar exhibited potential characteristics for environmental oversight, greenhouse gas (GHG) emission reduction, and soil fertility improvement. This review explores the impact of fundamental factors such as retention time, pyrolysis temperature, gas flow rate, and reactor design on biochar yield and properties. Collected data revealed the various applications of biochar, ranging from waste management and construction materials to the adsorptive removal of hydrocarbon lubricants from aqueous media, contaminant immobilization, and carbon sequestration. It has played mostly a significant share in climate change mitigation and an important role in soil amendments. Biochar improves soil improvement by increasing water retention (10%–30%), carbon sequestration, soil surface functionality, and providing high surface area with chemical stability. The assessment also reports the prospects and contests associated with biochar application uses in various agriculture cropping ecosystems. Inclusive, this review highlights the multifaceted characteristics of biochar as an adjustable on top of a sustainable solution addressing greenhouse gas emission, carbon sequestration, and environmental stresses. However, further research is needed to understand its long-term impacts and optimal applications fully.
基金funding provided by the National Natural Science Foundation of China(31971843 and 31271646)the Guangxi Natural Science Foundation,China(2021GXNSFBA196084)。
文摘The practice of conservation tillage or straw return to the farmland influences the grain yield and quality of rice(Oryza sativa).The key volatile compound responsible for the fragrance of fragrant rice is 2-acetyl-1-pyrroline(2-AP),which is significantly affected by field management measures.The purpose of this study was to investigate the impact of tillage management and straw return on the grain yield and biosynthesis of 2-AP in fragrant rice.This study was conducted over two years in 2016 and 2017 and used two fragrant rice cultivars(Meixiangzhan 2 and Xiangyaxiangzhan)as materials.The experimental design consisted of different tillage management and straw return treatments,which included three tillage management regimes:rotary tillage(T0),minimum tillage(T1),and no tillage(T2);and two straw return treatments:without straw return(S0)and straw return(S1).The straw used for the experiment was sourced from the residue of the corresponding fragrant rice cultivar harvested in the early season.Tillage management and straw return substantially affected the grain yields,grain quality,and 2-AP contents of both fragrant rice cultivars.Compared with the T0S0 treatment,tillage management and straw return resulted in 2-AP content improvements in 2016(12.41–116.85%)and 2017(34.85–103.89%)on average.Higher 2-AP contents were also detected in both fragrant rice cultivars in the T2S1 and T1S1 treatments.A structural equation model(SEM)demonstrated that the activities of enzymes related to fragrance metabolism in the leaves and grain jointly regulated the biosynthesis of precursors of fragrance metabolism in the grain,which further promoted the accumulation of 2-AP.In addition,a principal component analysis indicated that the T1S1 treatment was positively correlated with both 2-AP and grain yield.The SEM demonstrated that the enzymes related to nitrogen metabolism,parameters related to photosynthesis,and yield components contributed to the grain yield.The T1S1 treatment resulted in the highest average grain yield of 760.75 g m^(-2),which could be attributed to increases in various attributes,such as the leaf area index,SPAD value,nitrogen metabolism,panicle number m^(-2),and grain number per panicle.In summary,the minimum tillage and straw return(T1S1)treatment is more effective at simultaneously improving both the grain yield and 2-AP content in fragrant rice.
文摘We studied the genetic polymorphism among 29 clones of shisham （Dalbergia sissoo Roxb） belonging to different geographic regions using random amplified polymorphic DNA （RAPD） markers. Out of 30 primers used, only 20 primers generated polymorphism in amplified product. In total 232 bands were amplified with 20 primers, of which 192 （82%） were polymorphic with an average of 9.6 bands/primer. The resolving power （Rp） ranged from 2.14 （Primer 5） to 11.93 （Primer 4）. Primer 4 and Primer 3 possessed high Rp value. Polymorphism information content （PIC） ranged from 0.15 （Primer 5） to 0.37 （Primer 4）. Primer 4 amplified total 18 bands in 29 genotypes with PIC value of 0.37 hence; this set of primer was most informative. The similarity coefficient analysis revealed two clusters. The first cluster comprised of only 10 clones and the second major cluster comprised of 19 clones. The genetic similarity among 29 clones ranged from 25.86% （clone 10 and 235） to 100% （clone 19 and 59）, suggesting a wide genetic base in shisham clones.
基金financially supported by CSIR 12th Five Year Plan project BSC-0205CSIR-Phytopharmaceutical Mission Project HCP010+1 种基金CSIR-YSA (Young Scientist Award,P90807) Research Grantthe fellowship from Department of Biotechnology,India (GAP-2158).IIIM publication number: ⅢM/2222/2018
文摘Objective: Bergenia ciliata(Haw.) Sternb. is used in the Indian traditional system of medicine to treat various ailments including rheumatism and to heal wounds. The objective of the present study was to perform a preclinical characterization of the B. ciliata-based botanical extract IIIM-160.Methods: ⅢM-160 was chemically standardized and analyzed for heavy metal content, aflatoxins,pesticides and microbial load. The in vitro and in vivo efficacies were determined in suitable models of inflammation, arthritis and nociception. An acute oral toxicity study was performed in Swiss albino mice.A suitable oral formulation was developed and characterized.Results: Bergenin was found to be the major component(9.1% w/w) of ⅢM-160. The botanical lead displayed inhibition of lipopolysaccharide-induced production of proinflammatory cytokines in THP-1 cells, with selectivity toward interleukin-6(IL-6) and had an excellent safety-window. It showed anti-inflammatory, anti-arthritic and antinociceptive activity in animal models and was not toxic at oral doses up to 2 g/kg in Swiss-albino mice. The gastroretentive, sustained-release capsule formulation showed sustained-release of the bergenin over the period of 24 h, resulting in improved plasma-exposure of bergenin in Sprague–Dawley rats.Conclusion: The dual-activity of IL-6 inhibition and antinociception marks the suitability of ⅢM-160 for treating rheumatoid arthritis. This study will serve as the benchmark for further research on this botanical formulation.
文摘At the seedling stage, a small amount of N is required to boost growth of leguminous plants. A pot experiment was conducted to observe the effect of N fertilizer on various growth parameters and nodulation behavior of Pongamia pinnata under nursery conditions. After the estab- lishment of seedlings, four nitrogen treatments, 0, 40, 80 and 100 kg-ha^-1 N were applied in two equal splits. Monthly observations were taken for the morphological parameters viz. plant height, collar diameter, leaf number, root length, root shoot ratio, nodule number and weight per plant. Maximum plant height was recorded after application of N at 40 kg.ha^-1. Seasonally, the difference in collar diameter in rainy season was signifi- cantly higher than in winter or summer. However, more leaves were produced per plant at N-40 and N-100 treatments in winter and rainy seasons. Higher root length was recorded in rainy season than in winter or summer. Root biomass was higher than for stems or leaves. Seasonal effects of N-80 and N-40 treatments on leaf dry weight were significantly higher than for N-100 or N-0. Stem dry weight was higher at N-40 than at other treatments in winter and summer seasons. Root：shoot ratio was higher throughout winter to early summer. Nodule biomass was 2-3 times higher in rainy season compared to winter or summer. Maximum nodule number and biomass per plant were highest at N-40, followed by N-0, N-80 and N-100 treatments. New nodule formation started from June to the end of September. Maximum biomass per plant was recorded at N-40, followed by N-80, N-100 and N-0. Nitrogen treatment effect and seasonal behaviour interaction were not significant. Significantly higher numbers of nodules per plant were recorded in rainy season followed by summer and winter for all treatments. Higher nitrogen doses suppressed growth while lower doses promoted growth in Pongamia pinnata. Therefore, the lower nitrogen dose i.e., N-40 Kg.ha^-1 applied in two equal splits was suitable at the initial nursery stage for the increase in nodula- tion and biomass production.
文摘The performance and variability patterns in the wood element’s dimensions, specific gravity and growth parameters namely ramet height and GBH were evaluated in 16 clones of parents, F1 and F2 hybrids of Populus deltoides Bartr. ex Marsh. Ramet radial variations were nonsignificant, while inter-clonal variations due to interaction of clone/replication were significant for all the wood traits except vessel element length. Inter-clonal variations were significant only for fiber length and fiber wall thickness. Fiber length and specific gravity were significantly higher in female, while wall thickness and vessel element length were higher in male clones. Female parents （G48 and S7C8） showed higher fiber length and specific gravity than of the male parent （G3）, while vessel diameter and wall thickness were higher in male par- ent （G3）. There is not much difference in fiber length and vessel element’s dimensions among the parents, F1 and F2 generation hybrid clones. Specific gravity did not showed any trend for parents, F1 and F2 generations. Generally female clones showed higher growth rate. Broad sense heritability for wood traits ranged from 0.143 （fiber length） to 0.505 （fiber wall thickness）, while for growth traits it was 0.374 （GBH） and 0.418 （height）. Genetic gain for all the wood and growth traits was positive for most of the wood traits. The highly divergent male clone （78） and female clones （S7C8, G48, W/A 49） in number of combinations could be used for developing new hybrids of desired wood traits to develop new clones.
基金supported by the Guangdong Basic and Applied Basic Research Foundation,China(Grant No.2021A1515011255)Key-Area Research and Development Program of Guangdong Province,China(Grant No.2019B020221003)National Natural Science Foundation of China(Grant No.31471442)。
文摘To assess the effects of straw return coupled with deep nitrogen(N)fertilization on grain yield and N use efficiency(NUE)in mechanical pot-seedling transplanting(MPST)rice,the seedlings of two rice cultivars,i.e.,Yuxiangyouzhan and Wufengyou 615 transplanted by MPST were applied with N fertilizer at 150 kg/hm2 and straw return at 6 t/hm2 in early seasons of 2019 and 2020.The experiment comprised of following treatments:CK(no fertilizer and no straw return),MDS(deep N fertilization and straw return),MBS(broadcasting fertilizer and straw return),MD(deep N fertilization without straw return),MB(broadcasting fertilizer without straw return).Results depicted that the MDS treatment significantly increased the rice yield by 41.69%-72.22%due to total above-ground biomass,leaf area index and photosynthesis increased by 54.70%-55.80%,38.52%-52.17%and 17.89%-28.40%,respectively,compared to the MB treatment.In addition,the MDS treatment enhanced the total N accumulation by 37.74%-43.69%,N recovery efficiency by 141.45%-164.65%,N agronomic efficiency by 121.76%-134.19%,nitrate reductase by 46.46%-60.86%and glutamine synthetase by 23.56%-31.02%,compared to the MB treatment.The average grain yield and NUE in both years for Yuxiangyouzhan were higher in the MDS treatment than in the MD treatment.Hence,deep N fertilization combined with straw return can be an innovative technique with improved grain yield and NUE in MPST in South China.
文摘Berberis petiolaris Wall. ex G. Don, an unexplored medicinal plant belonging to the family Berberidaceae, is a large deciduous shrub found in Western Himalaya between 1800-3000 m. Chemical profiling of fruit, leaf, root and stem was done by direct analysis in real time mass spectrometry followed by multivariate analysis for discrimination among the plant parts. The bioactive compounds, including magnofiorine, berberine, jatrorrhizine, thalifendine/berberrubine, demethyleneberberine, reticuline, 8-oxoberberine, N-methyltetrahydroberberine, tetrahydropalmatine, tetrahydroberberine and palmatine, were identified by their exact mass measurement and the corresponding molecular formula of each compound. A comparative study of distribution pattern for all these bioactive alkaloids showed qualitative and quantitative variations in different parts of B. petiolaris. Principal component analysis clearly dis- criminated each part of B. petiolaris plant.
文摘Evaluation of thirty one core collections of Ocimum sanctum L. synonyms O. tenuiflorum L. collected from different ecological regions representing contrasting environment of India was carried out. All the collections were grown under sub-tropical region of Jammu, India. Study revealed wide range of variability in quantitive and qualitative attributes of oil. Essential oil content ranged between 0.16% ± 0.01% - 0.55% ± 0.08% showing the presence of fifteen constituents. Methyl eugenol (1.54% - 93.16%) and Eugenol (0.06% - 70.41%), were the major constituent. The other major constituent of the oil was β-Caryophyllene (4.60% - 33.77%) which was detected in almost all the collections. Borneol, Copane, α Caryophyllene were other constituents detected in almost all the accessions. α selinene was detected in traces in only three accessions (OS-01, OS-03, OS-50) and β-selinene was detected in four accessions (OS-01, OS-03, OS-50, OS-72. Accession OS-70 collected from Patna, showed distinct chemical profile having β-Elemene (32.81%), β-Cary- ophyllene (16.37%), Germacrene-D (18.05%), β-Ocimene (17.69%) and Copane (5.738%). Being distinct in oil profiling, Patna collection was designated as distinct chemotype. Collections OS-50 from Gwalior from Central India and OS-59 from Rajkot Western India have been identified as methyl eugenol (93.16%) and eugenol (70.41%) rich geno- types. The data collected provided useful information with respect to composition of essential oil among core collection evaluated representing various agro-climatic zones.
文摘Plant growth hormone BAP (benzyl amino purine), KIN (kinetin), NAA (1-naphthalene acetic acid) and IBA (indole-3 butyric acid) effect was studied on in vitro multiplication of shoots and rooting of Drepanostachyum falcatum. In vitro micropropagation of himalayan weeping bamboo is explained by in vitro shoot induction and proliferation. Excised explant with axillary bud is surface sterilized with 0.1% HgCl<sub>2</sub> for 10 - 12 minutes, cleaned with 90% ethanol and inoculated on liquid Murashige and Skoog (MS) culture medium supplemented with different concentrations of BAP/ KIN. Effect of BAP/KIN on shoot induction is with different rate and number of shoots produced by explants with axillary bud cultured on MS media supplemented with 0.0 mg/L BAP/KIN - 5.5 mg/L BAP/KIN. Shoot multiplication with highest rate is achieved on MS medium supplemented with 3.5 mg/L BAP after 4<sup>th</sup> sub-culturing. The most effective with highest rate and number of root induction combination is 6.5 mg/L IBA after 5 weeks. The roots produced by 6.5 mg/L IBA is best compared with other combination of auxin NAA (1-naphthalene acetic acid).
基金supported by the Key-Area Research and Development Program of Guangdong Province(2019B020221003)National Natural Science Foundation of Guangdong Province(008175187004)National Natural Science Foundation of China(31471442)。
文摘Deep placement of nitrogen fertilizer is a key strategy for improving nitrogen use efficiency. A two-year field experiment was conducted during the early rice growing seasons(March–July) of 2016 and 2017.The experimental treatments comprised two rice cultivars: Wufengyou 615(WFY 615) and Yuxiangyouzhan(YXYZ), and three N treatments: mechanical deep placement of all fertilizers as basal dose at 10 cm soil depth(one-time deep-placement fertilization, namely OTDP fertilization);manual surface broadcast(the common farmer practice) of 40% N fertilizer at one day before sowing(basal fertilizer)followed by broadcast application of 30% each at tillering and panicle initiation stages;and no fertilizer application at any growth stage as a control. One-time deep-placement fertilization increased grain yield of both rice cultivars by 11.8%–19.6%, total nitrogen accumulation by 10.3%–13.1%, nitrogen grain production efficiency by 29.7%–31.5%, nitrogen harvest index by 27.8%–30.0%, nitrogen agronomic efficiency by 71.3%–77.2%, and nitrogen recovery efficiency by 42.4%–56.7% for both rice cultivars, compared with the multiple-broadcast treatment. One-time deep-placement fertilization reduced CH4-induced global warming potential(GWP) by 20.7%–25.3%, N2O-induced GWP by 7.2%–12.3%, and total GWP by 14.7%–22.9% for both rice cultivars relative to the multiple-broadcast treatment. The activities of glutamine synthetase and nitrate reductase were increased at both panicle-initiation and heading stages in both rice cultivars following one-time deep-placement fertilization treatment. Larger leaf area index at heading stage and more favorable root morphological traits expressed as larger total root length, mean root diameter, and total root volume per hill were also observed. One-time deep-placement fertilization could be an effective strategy for increasing grain yield and nitrogen use efficiency and lowering greenhouse-gas emissions under mechanical direct-seeded cropping systems.
基金financial support to the present study by Council of Scientific and Industrial Research (CSIR)Government of India,under CSIR- networking project (BSC-0109) on ‘Plant Diversity: Studying adaptation biologyunderstanding/exploiting medicinally important plants for useful bioactives (SIMPLE)
文摘To understand the effect of climate change on constitutive antioxidant and biochemical metabolites in Western Himalayas, five medicinal herbs were selected and grown at two altitudes in Jammu(305 m) and Srinagar(1730 m) with subtropical and temperate climates, respectively.Significant variations were observed in phenols and flavonoids in Hypericum perforatum L., Matricaria chamomilla L., Thymus vulgaris L., Cynara cardunculus L. and Echinacea purpurea L. growing at two locations. High altitude temperate site show variable(up to 13 fold) increase in their content.Proteins(1.3- 1.8 times), sugars(2.8- 4.1 times) and free amino acid(1.04- 1.22 times) were also higher at Srinagar(1730 m). Within these plants, H.perforatum and M. chamomilla have shown higher accumulation of phenols, xanthophylls and proline even at subtropical environment in Jammu(305 m)suggesting potential for increasing their geographical area. The results demonstrate that changing environmental conditions significantly affect the bioactive constituents, which accumulate as a defence strategy by these temperate plants. Their medicinal significance during climate change scenario has also been discussed.
文摘Chrysopogon serrulatus(false beard-grass)is a dominant component of vegetation in the foothills of the Himalayas.To study whole plant morphology,individuals of C.serrulatus were collected from three plots at each of six locations spanning from 400 to 1,400 m.The population colonizing the highest elevation modifications in different plant organs.Roots showed increased metaxylem number and area.In the stem,especially outside of the vascular tissue,there was intensive sclerification indicative of increased xeromorphy as a survival strategy.At the highest elevation,leaves were wider;aerenchyma formation and increased sclerification were noted in the leaf sheath;and a greater proportion of storage parenchyma was observed in the leaf blade,all indicators of succulence.In contrast,leaves at lower elevations had xeric morphological features such as increased epidermal thickness,sclerification and more developed metaxylem area.In conclusion,shifting of morphological features in below-and above-ground plant parts of C.serrulatus were linked to shifts in environmental factors along this elevation gradient,thus enabling the successful distribution of this species along this elevation gradient.
基金financially supported by the CSIR-NET fellowship,the Council of Scientific and Industrial Research,New Delhi,India
文摘Rhizobia were isolated from Albizia lebbek （L） Benth. seed- lings collected from six different places, tested against the nodulation test and inoculated into 45 day old Albizia lebbek seedlings in sterile soil mixture under glass house conditions. After a period of two and three months, the plant samples were taken to study the influence of inoculation treatments on nitrogen fixation, assimilation, biomass production and nitrogen content in different plant parts. The seedlings inoculated with isolates III（1） and III（2） of Lalpani had the maximum nodular biomass,
文摘We studied radial and inter-progeny variations in the dimen- sions of the wood elements and specific gravity of 21 half sib progenies of Populus deltoides Bartr. ex Marsh. The female parents of half sib progenies were G48 and $7C13 clones. Variance ratio （F） test indicated that inter-progeny variations in the dimensions of wood elements and specific gravity were significant for all wood traits while variations were significant for radial location for specific gravity only. Hierarchical clus- ter analysis was done by Squared Euclidean Distance for all of 21 proge- nies considering six wood traits. 21 progenies were grouped into 4 clus- ters. Cluster 1 was the largest cluster with 11 progenies, whereas cluster 3 had only one progeny. Selected progenies in clusters 3 （progeny 155, male） and 4 （progeny 108, 196, both female） were highly divergent from the other progenies so they were used in combinations as parents of hybrids to develop new clones with desired characters. Progeny 155 showed higher growth, fiber dimensions, and specific gravity, thus, should be used for the development of new clones.
文摘The study of genetic variability is a prerequisite for any tree improvement program. Screening of clones showing the effect of dominance in growth and tree form is essential to identify productive clones, matched to sites. Our study performed in a clonal seed orchard at Lacchiwala of India, represented by 31 clones of Dalbergia sissoo （Shisham） Roxb. from diverse locations revealed significant variability at the 0.1% level of significance in various morphological traits. At the age of 13 years, clone 196 （Gonda） revealed maximum height of 20.2 m and a girth at breast height of 74.2 cm. The five identified clones viz. 196, 198, 192, 123 and 235 were well adapted to the climatic conditions of this zone, hence survived well and showed good performance compared to other clones. Heritability estimates of 87%, 83% and 80% for height, crown width and crown length respectively coupled with high genetic gains indicated strong genetic control of these variables. A correlation matrix of various growth attributes revealed positive correlation among these attributes. On the basis of the entire set of growth variables, the clones were grouped into two major clusters with three subgroups.
文摘Tea estates in Bangladesh are currently experiencing frequent waterlogging stress due to heavy rainfall or flooding under changing climate scenarios.The development of waterlogging-tolerant tea cultivars is,therefore,crucial for sustainable tea production with increased yield in waterlogging-affected areas.In this study,a total of two hundred tea genotypes were screened for waterlogging tolerance based on yield and quality potentials.Tea genotypes were raised at the nursery and evaluated with 13 traits at the seedling and mature stages.Descriptive and multivariate analysis of the recorded data of measured traits were performed for clustering the studied genotypes in relation to their yield and quality potential.The 200 tea genotypes were categorized into six clusters and the measured traits were classified into two groups.Cluster-5 comprised 46 closely related tea genotypes whereas other clusters-Cluster-1,2,3,4,and 6 contained 39,20,24,29,and 42 genotypes,respectively.PCA-biplot showed that the first two principal components(PC 1 and PC 2)cumulatively described 56.9%of total variations.From the genetic diversity analysis,the characteristics like green leaf yield(GLY),plucking points(PP),spreading of bush frame(SBF),plucking interval(PI),dormancy period(DR),black tea quality score(QSB),fermentation rate(SF)and number of pubescence(NP)exhibited high to moderate heritability,indicating to consider these traits as selection criteria for tea breeding program.The trait GLY showed a strong positive correlation with PP,and SBF and a negative association with PI and DR.The key quality trait,QSB had a positive correlation with SF and NP.Based on these studied descriptors,a total of 11 tea genotypes were selected,found potential for waterlogging tolerance,and can be considered for varietal improvement programs.
基金Council of Scientific and Industrial Research (CSIR) (File No: 09/560(0015)/2011-EMR-I)India and OCB programme of UNU, Tokyo, Japan for financial support to Balwant Rawat and Vikram Negi
文摘Forest vegetation of a protected area （Binsar Wildlife Sanctuary） in Kumaun region （west Himalaya） was analysed for structure, composition and representativeness across three different altitudinal belts, lower （1,6oo-1,8oo m a.s.1.）, middle （1,900-2,100 m a.s.1.） and upper （2,200-2,400 m a.s.1.） during 2oo9-2011 using standard phytosociological methods. Four aspects （east, west, north and south） in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper （18 species）, and lowest at lower altitudinal belt （15 species）. The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts （p〈0.05） while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons （p〉0.05）. The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes vis-a-vis role of ＇New＇ and ＇Not regenerating＇ species need priority attention while initiating conservation activities in the sanctuary. This study calls for exploring other less explored Wildlife Sanctuaries in the Himalaya and across the world, to achieve overall biodiversity status in these protected areas and thus to justify their role in conserving biodiversity in the region.
文摘Stripe rust, caused by Puccinia striiformis f. sp. tritici （Pst） is an important disease of wheat （Triticum aestivum） in Nepal, which is a part of the Himalayas stretching over the North of Nepal, India, Pakistan, Bhutan and beyond. Wheat production plays a crucial role in food security of the marginal hill farmers of Nepal. Frequent epidemics of the rust have caused huge loss in farmer＇s field. Periodic monitoring during 1980-2008 showed that changes in virulence occurred during this period. The objective of this study was to evaluate Pst resistance and its effective genes in wheat genotypes. For this, trap nurseries, wheat stripe rust differentials, commercial cultivars and advanced breeding lines were tested under artificial epiphytotic and natural hot spots conditions during 2005 to 2010. Four genes （Yr5, Yr10, Yr15 and YrSp） consistently showed resistance to the prevailing races. The gene Yr9 and Yr27 in combinations with Yrl8 were found effective. Other lines with combination of minor genes were also found effective. The genotypes Amadina, Kukuna, Tukuru, Kakatsi and Buck Buck widely used in breeding program were resistant. The cultivation of varieties WK1204, Gautam, Gaura and Dhaulagiri have ensured genetic diversity for the rust resistance and slowed down frequent occurrence of epidemics. The findings of these studies could help in developing effective varietal resistance program in the sub-continent.
