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It is indispensable to comprehend the mechanism that regulates plant responses to drought conditions to intensify the water use efficiency of stone fruits. The physiological, biochemical and molecular responses of drought-treated peach leaves were investigated. Results revealed that drought-treated plants manifested a significant attenuation in water potential as compared to control plants. Furthermore, sorbitol and proline contents were accumulated contrary to glucose, fructose, and sucrose that were dwindled significantly throughout the drought period. Similarly, the activities of antioxidant enzymes and expression pattern of related genes were hoisted to counter the lipid peroxidation in drought-treated plants. Moreover, reduced stomatal conductance has repressed the photosynthesis process and linked genes during drought stress. The expression level of regulatory genes (dehydration-responsive element-bindings and WRKYs) exhibited up-regulation in the drought-treated group. Overall, this study asserts that 'Yoshihime' peach cultivar possesses unique physiological, biochemical, and molecular responses under different spells of drought stress. [ABSTRACT FROM AUTHOR]

Drought is a ubiquitous abiotic factor that severely impedes growth and development of horticulture crops. The challenge postured by global climate change is the evolution of drought-tolerant cultivars that could cope with concurrent stress. Hence, in this study, biochemical, physiological and transcriptome analysis were investigated in drought-treated grapevine leaves. The results revealed that photosynthetic activity and reducing sugars were significantly diminished which were positively correlated with low stomatal conductance and CO 2 exchange in drought-stressed leaves. Further, the activities of superoxide dismutase, peroxidase, and catalase were significantly actuated in the drought-responsive grapevine leaves. Similarly, the levels of abscisic acid and jasmonic acid were also significantly increased in the drought-stressed leaves. In transcriptome analysis, 12,451 differentially-expressed genes (DEGs) were annotated, out of which 8021 DEGs were up-regulated and 4430 DEGs were down-regulated in response to drought stress. In addition, the genes encoding pathogen-associated molecular pattern ( PAMP ) triggered immunity ( PTI ), including calcium signals, protein phosphatase 2C, calcineurin B-like proteins, MAPKs, and phosphorylation ( FLS2 and MEKK1 ) cascades were up-regulated in response to drought stress. Several genes related to plant-pathogen interaction pathway ( RPM1, PBS1, RPS5, RIN4, MIN7, PR1, and WRKYs ) were also found up-regulated in response to drought stress. Overall the results of present study showed the dynamic interaction of DEG in grapevine physiology which provides the premise for selection of defense-related genes against drought stress for subsequent grapevine breeding programs. [ABSTRACT FROM AUTHOR]

Various bacterial species were isolated from different rice varieties: Kainat, Basmati-385, Super basmati, Basmati-386, KSK-133, Basmati-198, Basmati-2000x1053-2-2, Kasur, Stg 567989 and Basmati-2000x33797-1 collected from all agro ecological zones of Pakistan. When plated infected grain samples gave various bacterial colonies on Luria Bertani (L.B) agar medium. The isolates were identified on the basis of various morphological and biochemical features. Out of 22 isolates, five showed rod cell shape in microscope. Sixteen biochemical tests were conducted to characterize 22 isolates of bacteria. Gram stain demonstrated that three isolates were gram positive and rod shaped. All other isolates were gram negative. The presence of bacteria was also estimated in ten different varieties of rice. The highest presence of bacteria was observed in KSK-133, Kainat and Stg 567989. Burkholderia species and Enterobacter species have high frequency almost in all tested rice varieties. The overall objective of this study was to screen, classify and associate the bacterial species present on the basis of various morphological characteristics isolated from diverse rice genotype. The results demonstrated that collected and investigated rice varieties have a diverse range of bacterial species, some of which are considered as severe pathogens for plants. [ABSTRACT FROM AUTHOR]

The date fruit is a primary component of the human diet in many countries with arid and semiarid climates. The present study reflects the relationship of different biochemical attributes with progressive date fruit developmental stages. The study involved eight date palm (Phoenix dactylifera L.) cultivars from Pakistan examined at three different edible stages of dates (khalal, rutab and tamar). The antiradical efficiency (2.14- 0.36), antioxidant enzymes (catalase and peroxidase), total phenolic contents (468.99-108 mg GAE/100g, FW) and the soluble protein contents (5.73-2.75 g/100g) were higher in higher at khalal and thereafter, but declined at fully ripened (tamar) stage. Moreover, glucose (16.92-31.66%) and fructose (15.25-30.58%) have lower quantity at khalal and higher quantity at tamar stage, whereas non-reducing (sucrose) sugars were present only at khalal and rutab stage fruits. Makran and Chohara cultivars revealed best overall values in examined compounds. Our results revealed that variation in different biochemical attributes is mainly depended on the difference in fruit maturity stage and cultivar. Cultivars exhibiting high values of beneficial biochemical attributes may be considered for the expansion of date palm cultivation. [ABSTRACT FROM AUTHOR]

Trichoderma species are known to produce a number of metabolites that play important role in plant growth, survival and also to enhance defence mechanism of their hosts against certain pathogens. This study was conducted to investigate the effect of Trichoderma spp. on the growth activity in chickpea seedlings. Germination percentage of chickpea seeds was enhanced by some Trichoderma species culture extracts, the most active stimulators of seed germination were T. harzianum, T. viride and T. koningii extracts. Results revealed that the maximum seedling root length was obtained by T. harzianum followed by T. viride and T. koningii. However, some species produced extracts that were detrimental to germination and plant growth. The lowest root growth was attained from T. reesei and T. aureoviride among other Trichoderma filtrate treatments. The greatest seedling shoot length was observed with T. harzianum and T. viride followed by T. koningii and T. pseudokoningii while other Trichoderma cultural filtrates significantly suppressed the shoot length as compare to control value (P < 0.05). Fresh and dry weight and of chickpea seedling was also significantly higher in Trichoderma treatments as compared to control (P < 0.05). However, in T. reesei and T. aureoviride treatment, fresh and dry weight of seedling was considerably lower where as T. harzianum, T. viride and T. koningii had higher values for seedling dry matter. Results revealed that Trichoderma species are effective for growth parameters and can be used to further investigations and raise the yield of chickpea and other cereal crops. [ABSTRACT FROM AUTHOR]

BACKGROUND: Due to the rapid increase in world population, the demand for freshwater is increasing day by day. There is also immense pressure on the agriculture sector to produce more food with limited supplies of water. About 75% of freshwater is used in crop production out of which 63% is lost due to poor farm practices and evapotranspiration. Enhancement of crop water productivity for sustainable agriculture production especially in areas having water scarcity plausibly contributes towards the solution of water scarcity. RESULTS: The combined application of biochar and compost has a highly significant impact on maize yield with increased grain production, i.e. 6.44 and 6.52 t ha-1 at 60% irrigation level with combined application of biochar and compost as compared with control at 6.39 and 6.44 t ha-1 at 100% irrigation level in autumn and spring seasons, respectively, by saving 40% of water. Furthermore, the highest value of water productivity (1.51 and 1.16 kg m-3) was achieved at 60% irrigation level with combined application of soil amendments. Also, cost--benefit analysis has shown highest values of net benefit with soil organic amendments. CONCLUSIONS: It is concluded that addition of biochar and compost to soil has the potential to increase crop yield and growth even at low irrigation levels by enhancing water use efficiency. [ABSTRACT FROM AUTHOR]

Drought stress at the germination stage is an important environmental stress limiting crop yield. Hence, our study investigated comparative root transcriptome profiles of four contrasting soybean genotypes viz., drought-tolerant (PI342618B/DTP and A214/DTL) and drought-sensitive (NN86-4/DSP and A195/DSL) under drought stress using RNA-Seq approach. A total of 4850 and 6272 differentially expressed genes (DEGs) were identified in tolerant (DTP and DTL) and sensitive (DSP and DSL) genotypes, respectively. Principle component analysis (PCA) and correlation analysis revealed higher correlation between DTP and DTL. Both gene ontology (GO) and MapMan analyses showed that the drought response was enriched in DEGs associated with water and auxin transport, cell wall/membrane, antioxidant activity, catalytic activity, secondary metabolism, signaling and transcription factor (TF) activities. Out of 981 DEGs screened from above terms, only 547 showed consistent opposite expression between contrasting genotypes. Twenty-eight DEGs of 547 were located on Chr.08 rich in QTLs and "Hotspot regions" associated with drought stress, and eight of them showed non-synonymous single nucleotide polymorphism. Hence, 10 genes (including above eight genes plus two hub genes) were predicated as possible candidates regulating drought tolerance, which needs further functional validation. Overall, the transcriptome profiling provided in-depth understanding about the genetic mechanism and candidate genes underlying drought tolerance in soybean. [ABSTRACT FROM AUTHOR]

The type-B authentic response regulator (ARR-B) family members serve as DNA-binding transcriptional regulators, whose activities are probably regulated by phosphorylation/dephosphorylation, resulting in the rapid induction of type-A ARR genes. Type-B ARRs are believed to be involved in many biological processes, including cytokinin signaling, plant growth, and stress responses through a chaperone or by isomerization of proline residues during protein folding. The public availability of complete peach genome sequences allows the identification of 23 ARR-B genes by HMMER and blast analysis. Scaffold locations of these genes in the peach genome were determined, and the protein domain and motif organization of peach type-B ARRs were analyzed. The phylogenetic relationships between peach type-B ARRs were also assessed. The expression profiles of peach ARR-B genes revealed that most of the type-B ARRs showed high expression levels in tissues undergoing rapid cell division and may engage more cytokinins, like half-opened flowers, fruits at expansion stages, and young leaves. These findings not only contribute to a better understanding of the complex regulation of the peach ARR-B gene family, but also provide valuable information for future research in peach functional genomics. [ABSTRACT FROM AUTHOR]

The purpose of this research was to find indeginous insect associated fungi and their virulence against Bemisia tabaci. In present study, Trichoderma longibrachiatum was isolated from cotton mealybug and its pathogenicity test was conducted against Bemisia tabaci under controlled conditions. Entomopathogenic potential of T. longibrachiatum was accessed on nymphal and adult stages of B. tabaci. Entomopathogenic activity of T. longibrachiatum was severe on nymphal stage as compared to adult B. tabaci. Germination of conidia on outer surface of nymphal and adult stage of whitefly was also observed. The Results revealed that T. longibrachiatum is an entomopathogenic fungi against B. tabaci. Trichoderma is previously known as antagonistic organism against broad spectrum fungal as well as bacterial plant pathogens but it is not commonly found as insect pathogen. [ABSTRACT FROM AUTHOR]

A number of rhizobacterial isolates were isolated from the rhizospheric soil that was collected from infected chilli fields during survey. Main objective of the study was to identify the antagonistic bacterial isolates which have potential to restrict or suppressed the growth of Pythium debaryanum, the cause of chilli damping off. Thirty seven bacterial isolates were identified by their colony morphology and biochemical identification tests. Duel culture technique was applied to check the antagonistic behaviour of bacterial isolates. Among thirty seven bacterial isolates in which eleven isolates were shown significance antagonism towards the pathogenic fungal organism. Thirteen bacterial isolates (RB-17,RB-20,RB-21,RB-23,RB-25,RB-26,RB-27,RB-28,RB-31,RB-32,RB-34,RB36,RB-37) rendered between 77 and 96% inhibition while twenty four isolates rendered between 6 and 40%. Maximum inhibition was calculated in case of RB-37 (96%) and RB-34 (77%). Molecular identification was made by isolating bacterial DNA and amplification with 16SrRNA universal primers. PCR products were sequenced and phylogenetic analysis was done. Bacillus subtilis and Pseudomonas fluorescence were finally identified as potential antagonists against P.debaryanum. [ABSTRACT FROM AUTHOR]

Antimicrobial activity of Eruca sativa Mill. oil was evaluated against phytopathogenic bacterial species (Xenorhabdus luminescens, Acinetobacter sp., Bordetella pertussis, Ensifer adhaerens, Pseudomonas syringae, Acidovorax temperans, Xanthomonas axonopodis) and fungal species (Alternaria alternata, Dreschlera halodes, Aspergillus nidulans, Acremoniun kiliense, Fusarium oxysporum, Curvularia clavata, Rhizopus oryzae). Antifungal activity was determined on MEA while antibacterial activity on NA media plates to measure the effects of oil. The antimicrobial activity was tested by well diffusion method in vitro. E. sativa oil was found to be highly active against all fungal isolates tested as compared to bacterial isolates. Results showed evidence of high antibacterial activity against X. luminescens with inhibition zone of 3.1 cm. E. adhaerens and A. temperans exhibited least resistance against oil with 1.4 cm and 1.7 cm zone of inhibition respectively. The oil showed high antifungal activity in the range of 6.0-6.8cm inhibition zone against D. halodes, C. clavata, R. oryzae and A. nidulans whereas least active against F. oxysporum with 1.1cmzone of inhibition. The antimicrobial components from this oil can be used as an alternative to develop novel pesticides by replacing some chemical commercial antifungal and antibacterial for the plant diseases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Due to the rapid increase in world population, the demand for freshwater is increasing day by day. There is also immense pressure on the agriculture sector to produce more food with limited supplies of water. About 75% of freshwater is used in crop production out of which 63% is lost due to poor farm practices and evapotranspiration. Enhancement of crop water productivity for sustainable agriculture production especially in areas having water scarcity plausibly contributes towards the solution of water scarcity. RESULTS: The combined application of biochar and compost has a highly significant impact on maize yield with increased grain production, i.e. 6.44 and 6.52 t ha-1 at 60% irrigation level with combined application of biochar and compost as compared with control at 6.39 and 6.44 t ha-1 at 100% irrigation level in autumn and spring seasons, respectively, by saving 40% of water. Furthermore, the highest value of water productivity (1.51 and 1.16 kg m-3) was achieved at 60% irrigation level with combined application of soil amendments. Also, cost--benefit analysis has shown highest values of net benefit with soil organic amendments. CONCLUSIONS: It is concluded that addition of biochar and compost to soil has the potential to increase crop yield and growth even at low irrigation levels by enhancing water use efficiency. [ABSTRACT FROM AUTHOR]

Weeds are reservoirs for the survival of pathogenic microorganisms and cause of spread of infectious disease of plants through vectors. To minimize the spread of bacteria to other host crops, proper characterization is required to suggest suitable control strategy. Survey was conduct in December 2015, leaf blight was observed on barnyard grass growing in surroundings of citrus orchards located in Lahore, Pakistan. Isolation of the bacterium on nutrient agar medium was performed and their characterization based on morphological and biochemical tests. 16S rRNA was amplified directly with primers 27F/1492R, cloned and sequenced. Sequences were blast in NCBI data base which showed 99% identity to P. agglomerans strain. A neighbor-joining tree was generated with reported bacterial strain that were most closely to isolated strain P. agglomerans (LT592133). Pathogenicity test was conducted on barnyard grass with bacterial suspensions having 1.5 × 108 CFU/ml in controlled conditions to confirm Koch's postulates. According to results this is first report on the incidence of Pantoea agglomerans on Barnyard grass in Pakistan. [ABSTRACT FROM AUTHOR]

The present investigation deals with the morphological and biochemical identification of rhizobacteria having plant growth promoting characteristics, with a focus on the family Papilionaceae, whose representatives are widespread in nature as leguminous crops. Eleven bacterial strains were isolated from the rhizoplane of pea (Pisum sativum L.), chickpeas (Cicer arietinum L.) and clover (Trifolium pretense L.). The media used to isolate the rhizosphere bacteria were Luria Bertani (LB) agar and Nutrient agar (NA). Rhizosphere bacteria were identifiedbased on different characteristic i.e. phenotypic and biochemical characters. The isolated strains were characterized and assigned to various genera and species, such as Enterobacter aerogenes, Aureobacterium flavescens, Pseudomonas fluorescens, Kurthiasp., Acidovorax facilis, Bordetella pertussis, Corynebacterium sp., Bacillus sp., Curtobacterium albidum and Microbacterium lacticum. All identified species are given FCBP accession numbers and were stored for further use. [ABSTRACT FROM AUTHOR]

Conducive environmental conditions for the development of Mungbean yellow mosaic virus (MYMV) diseasewere characterized. Correlation of environmental conditions (maximum and minimum air temperature, relative humidity, rainfall, clouds and windvelocity) with MYMV disease incidence was determined on twenty varieties/lines of mungbean. It was revealed that maximum temperature had significantly negative correlation with the disease incidence. The disease incidence increasedwith the decrease of minimum temperature.Minimum temperature and wind velocity had non-significant correlation with MYMV disease incidence. It was also found that relative humidity and rainfall had significant correlation with Mungbean yellow mosaic virusdisease incidence. [ABSTRACT FROM AUTHOR]

Zingiber officinale L. is a common condiment for various foods and a long history of important traditional Medicine herb for the treatment of ailments and body disorders. Soil microorganisms are very important as almost every chemical transformation taking place in soil involves active contributions from soil microorganisms. In contrast, other soil microorganisms are pathogenic to plants and may cause considerable damage to crops. Large numbers of pathogenic microorganisms are routinely found in the soil and many can infect the plant through the roots. Through the current study describes the ginger rhizome associated soilborn bacterial strains. Rhizosphere bacteria were isolated from soil around the root zones of ginger fields. This study reports results concerning the isolation and identification of bacteria on the morphological basis and biochemical analysis. Ten species of bacteria belonging to eight different genera viz., Acidovorax temperans, Arthrobacter sp., Burkholderia pseudomallei, B. cepacia , Aeromonas hydrophila, A. veronii, Cupria-viridis sp., Bacillus sp., Flavobacterium odoratum, Oscillospira sp. were isolated and processed for identification by their enzymatic activity and carbohydrates utilization. [ABSTRACT FROM AUTHOR]

Twelve different sugar beet varieties were used to evaluate resistance against Fusarium oxysporum f. sp. betae and Alternaria alternata at Sugar Crops Research Program, NARC, Islamabad during 2012. In case of F. oxysporum only one variety (SD-PAK-01/07) was found moderately resistant, two moderately susceptible (SD-PAK-03/06 and EB-0809), seven susceptible (SD-PAK-04/06, SD-PAK-07/07, SD-12970, EB-0618, EB-0726, Sandrina and Ernestina) and two (SD-PAK-09/07 and California) were found highly susceptible. While in case of A. alternata leaf spots, only two varieties were found moderately resistant (California and Ernestina), three moderately susceptible (SD-PAK-01/07, SD-PAK-09/07 and EB-0809), three susceptible (SD-PAK-04/06, EB-0618 and Sandrina) and four (SD PAK-03/06, SDPAK- 07/07, S-12970 and EB-0726) were found highly susceptible. [ABSTRACT FROM AUTHOR]