Effect of treating eggs of cotton bollworm with Bacillus thuringiensis Berliner on functional response of Trichogramma brassicae Bezdenko

Cotton bollworm, Helicoverpa armigera (Hübner) is a cosmopolite insect pest of a wide spectrum of crops such as cotton, maize, tomato, soybean, etc. Egg parasitoids mainly Trichogramma brassicae Bezdenko and Bacillus thuringiensis Berliner (Bt) are biological control agents, that are used as components of sustainable and environmentally compatible IPM systems. Although Bt does not come in direct contact with egg parasitoids, it may persist within the host’s body and affect the quality of the host’s eggs via biochemical changes in their mother and possibly behaviour and potency of the parasitoids. In this study, the functional response of T. brassicae to different densities of H. armigera eggs was investigated in two sets of experiments at 26?±?1?°C, 65?±?5% RH, and 16: 8?h photoperiod. The first group was a control and the second one were eggs laid by hosts treated as 3rd instar larvae with LC₂₀ of Bt (determined as 9.8?×?10^5?IU/l of artificial diet based on a preliminary bioassay). A type III functional response was observed in both treatments with a direct density dependent mortality up to eight host eggs and an inverse one upward. Both handling time and searching efficiency were affected by Bt treatment as the handling time was increased by a factor of 1.5 and the searching efficiency was decreased by a factor of 0.6. The searching efficiencies were 0.0310?±?0.003 and 0.0182?±?0.005?h^?1, and handling times were 1.134?±?0.042 and 1.672?±?0.082?h in control and Bt treatment respectively.     

Synseed technology—A complete synthesis

Progress in biotechnological research over the last two decades has provided greater scope for the improvement of crops, forest trees and other important plant species. Plant propagation using synthetic seeds has opened new vistas in the field of agriculture. Synseed technology is a highly promising tool for the management of transgenic and seedless plant species, polyploid plants with elite traits and plant lines that are difficult to propagate through conventional propagation methods. Delivery of synseeds also alleviates issues like undertaking several passages for scaling up in vitro cultures as well as acclimatization to ex vitro conditions. Optimization of synchronized propagule development followed by automation of the whole process (sorting, harvesting, encapsulation and conversion) can enhance the pace of synseed production. Cryopreservation of encapsulated germplasm has now been increasingly used as an ex vitro conservation tool with the possible minimization of adverse effects of cryoprotectants and post-preservation damages. Through synseed technology, germplasm exchange between countries could be accelerated as a result of reduced plant quarantine requirements because of the aseptic condition of the plant material.     

Chemical Composition and Bioactivities of Essential Oil from Leaves of Syzygium cumini (L.) Skeels Native to Punjab,Pakistan

Herbal medicines are widely used for the treatment of different types of diseases like skin and throat infections and other diseases in developing countries. Syzygium cumini (L.) Skeels fruit, leaves and bark were used for the remedies of different diseases anciently. The aim of the present study was to evaluate the chemical profile of Syzygium cumini leaves essential oil (EO) from Punjab, Pakistan. The essential oil was isolated using hydrodistillation technique and analyzed by gas chromatography (GC) and gas chromatography‐mass spectrometry (GC/MS). Free radical scavenging capacity and antioxidant activity were assessed by using DPPH radical scavenging ability, inhibition of linoleic acid peroxidation, bleaching of β‐carotene in linoleic acid system and reducing power assays. Antimicrobial potential was assessed by disc diffusion assay and measurement of minimum inhibitory concentration (MIC) using resazurin microtiter‐plate assay. The anti‐heme biocrystallization activity of EO was also assessed. The major components (>3%) found in Syzygium cumini leaves EO were β‐farnesene (3.42 %), caryophyllenol (3.46 %), terpinen‐4‐ol (3.61 %), β‐myrcene (3.90 %), γ‐cadinene (4.09 %), fenchol (4.22 %), cis‐β‐ocimene (4.40 %) and 5‐methyl‐1,3,6‐heptatriene (4.90 %). Excellent antioxidant, antimicrobial and weak antimalarial potential was observed. It can be concluded that Syzygium cumini leaves EO has potential application for food and pharmaceutical industries.     

Development and utilization of an InDel marker linked to the fertility restorer genes of CMS-D8 and CMS-D2 in cotton

Molecular Biology Reports - The cytoplasmic male sterility (CMS) system is a useful tool for commercial hybrid cotton seed production. Two main CMS systems, CMS-D8 and CMS-D2, have been recognized...     

Genetic diversity of Paramecium species on the basis of multiple loci analysis and ITS secondary structure models

Among ciliates, Paramecium has become a privileged model for the study of “species problem” particularly in the case of the “Paramecium aurelia complex” that has been intensely investigated. Despite extensive studies, the taxonomy of Paramecium is still challenging. The major problem is an uneven sampling of Paramecium with relatively few representatives of each species. To investigate species from the less discovered region (Pakistan), 10 isolates of Paramecium species including a standing-alone FT8 strain previously isolated by some of us were subjected to molecular characterization. Fragments of 18S recombinant DNA (rDNA), ITS1-5.8S-ITS2-5′LSU rDNA, cytochrome c oxidase subunit II, and hsp70 genes were used as molecular markers for phylogenetic analysis of particular isolates. The nucleotide sequences of polymerase chain reaction products of all markers were compared with the available sequences of relevant markers of other Paramecium species from GenBank. Phylogenetic trees based on all molecular markers showed that all the nine strains had a very close relationship with Paramecium primaurelia except for the FT8 strain. FT8 consistently showed its unique position in comparison to all other species in the phylogenetic trees. Available sequences of internal transcribed spacer 1 (ITS1) and ITS2 and some other ciliate sequences from GenBank were used for the construction of secondary models. Two highly conserved helices supported by compensatory base changes among all ciliates of ITS2 secondary structures were found similar to other eukaryotes. Therefore, the most conserved 120 to 180 base pairs regions were identified for their comparative studies. We found that out of the three helices in ITS1 structure, helix B was more conserved in Paramecium species. Despite various substitutions in the primary sequence, it was observed that secondary structures of ITS1 and ITS2 could be helpful in interpreting the phylogenetic relationships both at species as well as at generic level.     

A micropropagation protocol for <Emphasis Type="Italic">Cassia angustifolia</Emphasis> Vahl. from root explants

The aim of this study was to develop a new micropropagation system for Cassia angustifolia Vahl., an important medicinal legume using root explant as starting material. Root explants taken from 30-day-old aseptic seedlings were cultured on Murashige and Skoog (MS) medium supplemented with different plant growth regulators: 6-benzyladenine (BA), kinetin (Kn), and thidiazuron (TDZ). Organogenic nodular calli obtained on MS + TDZ (1.0 μM) were transferred to shoot regeneration medium supplemented with different cytokinins (BA, Kn or TDZ) either alone or in combination with auxin:indole-3-acetic acid or α-naphthalene acetic acid. Maximum shoot regeneration frequency (90%) was obtained on MS + BA (2.5 μM) + NAA (0.6 μM) wherein a maximum of 42.76 ± 1.47 shoot buds per explant were induced with a maximum conversion rate of 35.63 ± 0.75 shoots per explant and average shoot length of 5.43 ± 0.20 cm. Elongated microshoots were successfully rooted under ex vitro conditions by pulse treatment in 200 μM of indole-3-butyric acid for half an hour. Microshoots were rooted, acclimatized and hardened off simultaneously in sterilized soilrite inside the growth room and then established in pots containing sterilized soil and manure (1:1) and grown under greenhouse condition with 90% survival rate. The histological sections at different developmental stages of shoot buds revealed the organization of nodular meristematic zone leading to the orientation and differentiation of shoot buds in large number and thereafter conversion into healthy shoots.     

E6 and E7 from human papillomavirus type 16 cooperate to target the PDZ protein Na/H exchange regulatory factor 1

Previous studies have shown that the PDZ-binding motif of the E6 oncoprotein from the mucosal high-risk (HR) human papillomavirus (HPV) types plays a key role in HPV-mediated cellular transformation in in vitro and in vivo experimental models. HR HPV E6 oncoproteins have the ability to efficiently degrade members of the PDZ motif-containing membrane-associated guanylate kinase (MAGUK) family; however, it is possible that other PDZ proteins are also targeted by E6. Here, we describe a novel interaction of HPV type 16 (HPV16) E6 with a PDZ protein, Na(+)/H(+) exchange regulatory factor 1 (NHERF-1), which is involved in a number of cellular processes, including signaling and transformation. HPV16 E6 associates with and promotes the degradation of NHERF-1, and this property is dependent on the C-terminal PDZ-binding motif of E6. Interestingly, HPV16 E7, via the activation of the cyclin-dependent kinase complexes, promoted the accumulation of a phosphorylated form of NHERF-1, which is preferentially targeted by E6. Thus, both oncoproteins appear to cooperate in targeting NHERF-1. Notably, HPV18 E6 is not able to induce NHERF-1 degradation, indicating that this property is not shared with E6 from all HR HPV types. Downregulation of NHERF-1 protein levels was also observed in HPV16-positive cervical cancer-derived cell lines, such as SiHa and CaSki, as well as HPV16-positive cervical intraepithelial neoplasia (CIN). Finally, our data show that HPV16-mediated NHERF-1 degradation correlates with the activation of the phosphatidylinositol-3'-OH kinase (PI3K)/AKT signaling pathway, which is known to play a key role in carcinogenesis.     

Effects of Plant Growth Regulators on Seed Filling,Endogenous Hormone Contents and Maize Production in Semiarid Regions

In this study, we determined whether the application of uniconazole alone or combined with ethephon could enhance the seed-filling rates in maize by regulating the endogenous hormone contents. Uniconazole was applied to the foliage at concentrations of 0 (CK), 25 (U₂₅), 50 (U₅₀) and 75 (U₇₅) mg L⁻¹ at the 12-leaf stage. In addition, uniconazole was applied to the foliage at the 12-leaf stage and ethephon at 10 days after silking stage at concentrations of 0 (CK), 25 mg L⁻¹ uniconazole + 100 mg L⁻¹ ethephon (U₂₅ + E₁₀₀), 50 mg L⁻¹ uniconazole + 200 mg L⁻¹ ethephon (U₅₀ + E₂₀₀) and 75 mg L⁻¹ uniconazole + 300 mg L⁻¹ ethephon (U₇₅ + E₃₀₀). Uniconazole applied alone or in combination with ethephon significantly improved ear characters and grain yield. Uniconazole applied alone or combination with ethephon significantly improved the dry matter accumulation in seeds and seed-filling rates. Uniconazole significantly increased the abscisic acid (ABA) and zeatin (Z) + zeatin riboside (ZR) contents of seeds, but reduced the gibberellic acid (GA) contents. The application of uniconazole combined with ethephon decreased the ABA, Z + ZR and GA contents in seeds. The ABA and Z + ZR contents were significantly positively correlated, whereas the GA content was negatively correlated with the maximum seed weight, maximum seed-filling rate and mean seed-filling rate. The application of uniconazole alone significantly improved the seed-filling rates in maize by regulating the endogenous hormone contents. Thus, we conclude that uniconazole application at 50 mg L⁻¹ in the 12-leaf stage can enhance the maize production.

     

Seed priming improves the emergence potential,growth and antioxidant system of Moringa oleifera under saline conditions

Moringa oleifera is a multipurpose plant which is now being promoted as a fodder crop. The present study was conducted to induce the tolerance in moringa plants to emerge and grow under saline conditions. For this, moringa seeds were primed with aerated water (hydropriming) and moringa leaf extract (MLE) for 12 and 24 h and studied for its emergence, potential growth behaviour, mineral composition, chlorophyll contents and antioxidant activities in comparison with unprimed seeds to investigate the physiological changes in moringa plants under saline conditions. The seeds were sown in plastic pots filled with acid washed sand at four salinity levels (3, 6, 10, 14 dS m^?1) in a completely randomized design with three replications. It was found that salinity >6 dS m^?1 reduced the emergence, growth and vigour of moringa plants but hydropriming (12 h) enhanced moringa emergence at 10 dS m^?1 followed by MLE priming (12 h). Maximum aboveground biomass and photosynthetic pigments were recorded when the seeds were hydroprimed (12 h) but maximum root length and number of roots were found in MLE primed (12 h) moringa plants. Significant decrease in K⁺:Na⁺ ratio with increasing salinity levels resulted in low K⁺ and Mg²⁺ uptake and Na⁺ toxicity in moringa leaves which resulted in reduced chlorophyll contents at 14 dS m^?1 but a significant increase in chlorophyll a and b contents and total phenolics were found in hydroprimed seeds (12 h) while the antioxidant activities of superoxide dismutase, peroxidase and catalas were improved by MLE priming (12 h). This study concludes that moringa emergence and growth performance can be improved by hydropriming under saline conditions.