Inoculation with Pseudomonas spp. Containing ACC-Deaminase Partially Eliminates the Effects of Drought Stress on Growth,Yield,and Ripening of Pea (Pisum sativum L.)

Two preselected plant growth promoting rhizobacteria(PGPR) containing 1-aminocyclopropane-1-carboxylate(ACC) -deaminase(EC 4.1.99.4) were used to investigate their potential to ameliorate the effects of drought stress on growth,yield,and ripening of pea(Pisum sativum L.) . Inoculated and uninoculated(control) seeds of pea cultivar 2000 were sown in pots(four seeds pot-1) and placed in a wire house. The plants were exposed to drought stress at different stages of growth(vegetative,flowering,and pod formation) by skipping the respective irrigation. Results revealed that inoculation of peas with PGPR containing ACC-deaminase significantly decreased the "drought stress imposed effects" on the growth and yield of peas. Exposure of plants to drought stress at vegetative growth stage significantly decreased shoot growth by 41% in the case of uninoculated plants,whereas,by only 18% in the case of inoculated plants compared to nonstressed uninoculated control. Grain yield was decreased when plants were exposed to drought stress at the flowering and pod formation stage,but inoculation resulted in better grain yield(up to 62% and 40% higher,respectively) than the respective uninoculated nonstressed control. Ripening of pods was also delayed in plants inoculated with PGPR,which may imply decreased endogenous ethylene production in inoculated plants. This premise is further supported by the observation that inoculation with PGPR reduced the intensity of classical "triple" response in etiolated pea seedlings,caused by externally applied ACC. It is very probable that the drought stress induced inhibitory effects of ethylene could be partially or completely eliminated by inoculation with PGPR containing ACC-deaminase.

Phytoremediation of heavy metal polluted soils and water:Progresses and perspectives

Environmental pollution affects the quality of pedosphere,hydrosphere,atmosphere,lithosphere and biosphere.Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources.Phytoremediation,being more cost-effective and fewer side effects than physical and chemical approaches,has gained increasing popularity in both academic and practical circles.More than 400 plant species have been identified to have potential for soil and water remediation.Among them,Thlaspi,Brassica,Sedum alfredii H.,and Arabidopsis species have been mostly studied.It is also expected that recent advances in biotechnology will play a promising role in the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the higher biomass producing cultivated species in the times to come.This paper attempted to provide a brief review on recent progresses in research and practical applications of phytoremediation for soil and water resources.

Seed Priming Influence on Early Crop Growth, Phenological Development and Yield Performance of Linola (Linum usitatissimum L.)

Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L-1 salicylic acid(SA), 2.2% CaCl2 and 3.3% moringa leaf extract(MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2reduced crop branching and fl owering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index(4.12%) and oil contents(13.39%) for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl2 or MLE can play signifi cant role to improve early crop growth and seed yields of linola.

Prediction of Anoxic Sulfide Biooxidation Under Various HRTs Using Artificial Neural Networks

Objective During present investigation the data of a laboratory-scale anoxic sulfide oxidizing (ASO) reactor were used in a neural network system to predict its performance. Methods Five uncorrelated components of the influent wastewater were used as the artificial neural network model input to predict the output of the effluent using back-propagation and general regression algorithms. The best prediction performance is achieved when the data are preprocessed using principal components analysis (PCA) before they are fed to a back propagated neural network. Results Within the range of experimental conditions tested, it was concluded that the ANN model gave predictable results for nitrite removal from wastewater through ASO process. The model did not predict the formation of sulfate to an acceptable manner. Conclusion Apart from experimentation, ANN model can help to simulate the results of such experiments in finding the best optimal choice for ASO based denitrification. Together with wastewater collection and the use of improved treatment systems and new technologies, better control of wastewater treatment plant (WTP) can lead to more effective maneuvers by its operators and, as a consequence, better effluent quality.

Papaya Ring Spot Virus:An Understanding of a Severe Positive-Sense Single Stranded RNA Viral Disease and Its Management

Viral diseases have been studied in-depth for reducing quality,yield,health and longevity of the fruit,to highlight the economic losses.Positive-sense single-stranded RNA viruses are more devastating among all viruses that infect fruit trees.One of the best examples is papaya ringspot virus(PRSV).It belongs to the genus Potyvirus and it is limited to cause diseases on the family Chenopodiaceae,Cucurbitaceae and Caricaceae.This virus has a serious threat to the production of papaya,which is famous for its high nutritional and pharmaceutical values.The plant parts such as leaves,latex,seeds,fruits,bark,peel and roots may contain the biological compound that can be isolated and used in pharmaceutical industries as a disease control.Viral disease symptoms consist of vein clearing and yellowing of young leaves.Distinctive ring spot patterns with concentric rings and spots on fruit reduce its quality and taste.The virus has two major strains P and W.The former cause disease in papaya and cucurbits while the later one in papaya.Virion comprises 94.4%protein,including a 36 kDa coat protein which is a component responsible for a non-persistent transmission through aphids,and 5.5%nucleic acid.Cross protection,development of transgenic crops,exploring the resistant sources and induction of pathogen derived resistance have been recorded as effective management of PRSV.Along with these practices reduced aphid population through insecticides and plant extracts have been found ecofriendly approaches to minimize the disease incidence.Adoption of transgenic crops is a big challenge for the success of disease resistant papaya crops.The aim of this review is to understand the genomic nature of PRSV,detection methods and the different advanced control methods.This review article will be helpful in developing the best management strategies for controlling PRSV.

Role of secondary metabolites of wild marigold in suppression of Johnson grass and Sun spurge

Objective: To analyze the wild marigold [(Tagetes minuta L.)(T. minuta)] leaf extract with respect to phytochemicals and allelopathic activity. Methods: The aqueous extracts of T. minuta leaves at concentrations of 50%, 75% and 100% were prepared. Preliminary phytochemical analysis was carried out and then allelopathic ef ect of T. minuta on root length, shoot length, germination, fresh and dry weight of Johnson grass and Sun spurge was tested on i lter paper and in soil.Results: Qualitative phytochemical analysis showed the presence of alkaloids, tannins, saponins, l avonoides and terpenoids. The higher concentrations proved to be signii cantly ef ective in reducing almost all the parameters of Sun spurge and Johnson grass in i lter paper bioassay. Supplemented with the soil, all concentrations of leaf extract showed reduction in germination, root and shoot growth, fresh and dry weight of Sun spurge; however, 100% concentration signii cantly reduced the germination of Johnson grass. Conclusions: This study suggests that marigold allelochemicals can be used as an integrated weed management for the production of better crop yield.

Impact of population dynamics on Margalla Hills Ecosystem:a community-level case study

Margalla Hills National Park(MHNP) is a declared natural reserve of Pakistan,and Saidpur village is located at its foothills.To sustain livelihood,Saidpur community relies on natural resources and has established an intriguing relationship with the surrounding ecosystem.Human intrusion and related impacts were investigated through self-structured questionnaire from village community to gather information about demography,life practices,natural resource use,and their perception about the environment.Quadrat analysis revealed that the overall plant density was<4 plants/m^2,whereas ordination biplot has indicated significant reduction in plant cover and sparse distribution of species in areas close to human settlement.Survey results show that more than 50%families rely on forest wood as fuel source.Logistic regression has identified education paucity(odds ratio,OR=2.6,95%confidence interval,CI=1.0-6.7),large family size(OR= 5.0,95%CI=1.5-16.6),and fuel type(OR=3.5,95%CI=1.2-9.9)as significant predictors of accelerated forest cutting in MHNP.Male members were mostly illiterate and in favor to promote construction activities which reflects their low concern and casual attitude toward resource conservation.In this study,lack of awareness and peoples' dependency on natural resources emerged as priority challenges,and hence,we suggest provision of alternate fuel sources,better education and sustained income resources as incentives to bring behavioral change.It is pivotal to involve local community before the adoption of any conservation plan as intervention strategy to protect MHNP ecosystem.

Identification of Potential F₁Hybrids in Maize Responsive to Water Deficient Condition

The assessment of heterotic F1 combinations is a basic requisite for hybrid seed development. A set of 30 F1 hybrids along with their parental inbred lines were evaluated under both normal and water deficit conditions for various physiological and agronomic traits. Highly significant mean squares due to general combining ability, specific combining ability and reciprocal effect were observed for all traits under both water regimes. Components of variation exhibited greater estimates for GCA variance (б2g) than SCA variance (б2s) for majority of the traits under both normal and stress conditions depicting the predominant role of additive genetic component. Inbred lines NCIL-20-20, D-157 and OH-8 were found to be the best general combiner on the basis of performance regarding grain yield per plant under water deficit condition. The F1 combinations namely, NCIL-20-20 × D-109, NCIL-20-20 × OH-8 and D-157 × NCIL-20-20 were out-performers based on yield and yield attributes under water deficit conditions. On the basis of our results, we recommend these hybrids for further exploitation to assess their potential for commercial cultivation under water deficit condition.

Antagonistic Potential of Bacterial Species against Fungal Plant Pathogens(FPP)and Their Role in Plant Growth Promotion(PGP):A Review

Since the 19th century to date,the fungal pathogens have been involved in causing devastating diseases in plants.All types of fungal pathogens have been observed in important agricultural crops that lead to significant pre and postharvest losses.The application of synthetic fungicide against the fungal plant pathogens(FPP)is a traditional management practice but at the same time these fungicides kill other beneficial microbes,insects,animal,and humans and are harmful to environment.The antagonistic microorganism such as bacteria are being used as an alternate strategy to control the FPP.These antagonistic species are cost-effective and eco-friendly in nature.These biocontrol bacteria have a broad mechanism against fungal pathogens present in the phyllosphere and rhizosphere of the plant.The antagonistic bacteria have different strategies against the FPP,by producing siderophore,biofilm,volatile organic compounds(VOCs),through parasitism,antibiosis,competition for limited resources and induce systemic resistance(ISR)in the host plant by activating the immune systems.The commercial bio-products synthesized by the major bacterial species Pseudomonas syringae,Burkholderia cepacia,Streptomyces griseoviridis,Pseudomonas fluorescens and Bacillus subtilis are used to control Fusarium,Pythium,Rhizoctonia,Penicillium,Alternaria,and Geotrichum.The commercial bio-formulations of bacteria act as both antifungal and plant growth regulators.The Plant growth-promoting rhizobacteria(PGPR)played a significant role in improving plant health by nitrogen-fixing,phosphorus solubilization,phytohormones production,minimizing soil metal contamination,and by ACC deaminase antifungal activities.Different articles are available on the specific antifungal activity of bacteria in plant diseases.Therefore,this review article has summarized the information on biocontrol activity of bacteria against the FPP and the role of PGPR in plant growth promotion.This review also provided a complete picture of scattered information regarding antifungal activities of bacteria and the role of PGPR.

不同土壤水分调控技术对土壤含水量和鸭梨果实品质的影响

以13、20和30年生鸭梨为试材,分别在辛集市新垒头、泊头市苗圃场和曲阳县寺南庄梨园,研究了覆膜、定期浇水和对照3种不同土壤水分调控技术对土壤含水量和鸭梨品质的影响。结果表明,土壤含水量以定期浇水最高,对照和覆膜较低;平均单果重以定期浇水最大,覆膜次之,对照最小;果肉硬度则正相反;可溶性固形物、总糖含量和糖酸比以对照最高,覆膜次之,定期浇水最低;可滴定酸含量以定期浇水最高,对照和覆膜较低;Vc含量以覆膜最高,对照次之,定期浇水最低;果实淀粉和果皮叶绿素含量均表现为对照>定期浇水>覆膜。

Assessment of Genetic Variation Within Indian Mustard (Brassica juncea) Germplasm Using Random Amplified Polymorphic DNA Markers

Genetic diversity among 45 Indian mustard (Brassica juncea L.) genotypes comprising 37 germplasm collections, five advance breeding lines and three improved cultivars was investigated at the DNA level using the random amplified polymorphic DNA (RAPD) technique. Fifteen primers used generated a total of 92 RAPD fragments, of which 81 (88%) were polymorphic. Of these, 13 were unique to accession 'Pak85559'. Each primer produced four to nine amplified products with an average of 6.13 bands per primer. Based on pairwise comparisons of RAPD amplification products, Nei and Li's similarity coefficients were calculated to evaluate the relationships among the accessions. Pairwise similarity indices were higher among the oilseed accessions and cultivars showing narrow ranges of 0.77-0.99. An unweighted pair-group method with arithmetic averages cluster analysis based on these genetic similarities placed most of the collections and oilseed cultivars close to each other, showing a low level of polymorphism between the accessions used. However, the clusters formed by oilseed collections and cultivars were comparatively distinct from that of advanced breeding lines. Genetically, all of the accessions were classified into a few major groups and a number of individual accessions. Advanced breeding lines were relatively divergent from the rest of the accessions and formed independent clusters. Clustering of the accessions did not show any pattern of association between the RAPD markers and the collection sites. A low level of genetic variability of oilseed mustard was attributed to the selection for similar traits and horticultural uses. Perhaps close parentage of these accessions further contributed towards their little diversity. The study demonstrated that RAPD is a simple and fast technique to compare the genetic relationship and pattern of variation among the gene pool of this crop.

Role of Ca^(2+) on Growth of Brassica campestris L.and B.juncea(L.) Czern & Coss under Na^+ Stress

Root and shoot growth of Brassica campestris L.and B.juncea increased significantly(P<0.01) with enhanced Ca2+ treatment along with 60 mM NaCl in the root medium.The maximum fresh mass of shoot and root in B.juncea was recorded at 10 mM Ca2+ concentration.The relative growth rate of shoot of both species reached its maximum at 8 mM of Ca2+ concentration.Average rate of Ca2+ intake(Ca) was higher in B.juncea than B.campestris.In B.juncea,the average transport of Ca2+ to shoot increased by 19%,38%,119%,125% and 169% compared with the control.Furthermore specific utilization rate of Ca2+ was higher in B.juncea than B.campestris.In B.campestris it increased by 9%,32%,41% and 59% at 4,6,8,and 10 mM of calcium in comparison to 2 mM Ca2+ treatment.At 4,6,8 and 10 mM of Ca2+ application,the increase in the leaf area ratio was 10,17,23 and 30%,respectively.In the shoot and root portions of B.campestris and B.juncea,Ca2+ had a linear relationship with potassium and sulfur,whereas it was in antagonism with sodium ion.

Ethnopharmacological evaluation and antioxidant activity of some important herbs used in traditional medicines

OBJECTIVE: To document the indigenous knowledge and evaluate the antioxidant activity of medicinal herbs used for treatment of various diseases.METHODS: The ethnomedicinal data were collected through semi-structured interviews of local informants along with collection of herbarium specimens. The antioxidant activity was evaluated by using 1-diphenyl-2-picryl-hydrazyl radical scavenging assay.RESULTS: A total of 12 important medicinal herbs were evaluated for ethnomedicinal uses and antioxidant activity. Medicinal plant diversity showed that Solanaceae was the dominating family(3 spp.),followed by Asteraceae and Lamiaceae(both 2spp.). Leaves(31%) were most frequently used in preparation of traditional medicines, and the most recommended mode of preparation was powder(28%). The antioxidant results revealed that thehighest activity was found in Atropa acuminata and Crocus sativus.CONCLUSION: The results of this study proved that A. accuminata and C. sativus can be the excellent sources of antioxidant compounds. A sustainable use and conservation of the valuable natural resource greatly promote the development of functional food additives and cosmetics.

HT-SuperSAGE of the gut tissue of a Vip3Aa-resistant Heliothis virescens (Lepidoptera: Noctuidae) strain provides insights into the basis of resistance

Multitoxin Bt-crops expressing insecticidal toxins with different modes of action, for example, Cry and Vip, are expected to improve resistance management in target pests. While Cry1A resistance has been relatively well characterized in some insect species, this is not the case for Vip3A, for which no mechanism of resistance has yet been identified. Here we applied HT-SuperSAGE to analyze the transcriptome of the gut tissue of tobacco budworm Heliothis virescens (F.) laboratory-selected for Vip3Aa resistance. From a total of 1 324 252 sequence reads, 5 895 126-bp tags were obtained representing 17 751 nonsingleton unique transcripts (UniTags) from genetically similar Vip3Aa-resistant (Vip- Sel) and susceptible control (Vip-Unsel) strains. Differential expression was significant (≥2.5 fold or ≤0.4;P < 0.05) for 1989 sequences (11.2% of total UniTags), where 420 represented overexpressed (OE) and 1569 underexpressed (UE) genes in Vip-Sel. BLASTN searches mapped 419 UniTags to H. virescens sequence contigs, of which, 416 (106 OE and 310 UE) were unambiguously annotated to proteins in NCBI nonredundant protein databases. Gene Ontology distributed 345 of annotated UniTags in 14 functional categories with metabolism (including serine-type hydrolases) and translation/ribosome biogenesis being the most prevalent. A UniTag homologous to a particular member of the REsponse to PAThogen (REPAT) family was found among most overexpressed, while UniTags related to the putative Vip3Aa-binding ribosomal protein S2 (RpS2) were underexpressed. qRT-PCR of a subset of UniTags validated the HT-SuperSAGE data. This study is the first providing lepidopteran gut transcriptome associated with Vip3Aa resistance and a foundation for future attempts to elucidate the resistance mechanism.