Biological Suppression of Major Mealybug Species on Horticultural Crops in India

Mealybugs, known to be 'hard to kill pests', live in protected areas and most stages in their life cycle are covered in a waxy coating. Several insecticides are found ineffective against mealybugs. Fortunately, mealybugs - being sessile insects - are more amenable to biological control. The exotic parasitoid, Leptomastix dactylopii How., was found to be highly effective in suppressing citrus mealybug, Planococcus citri (Risso.) permanantly on citrus, sapota, guava, pomegranate and coffee. This is one of the recent successes in classical biological control attempts in India. However, the Australian ladybird beetle, Cryptolaemus montrouzieri Muls., often provides spectacular control of heavy infestation of P. citri on acid lime, lemon, sweet orange, pummelo, Crossandra and custard apple. Though Anagyrus dactylopii (How.), is a potential parasitoid of pink hibiscus mealybug, Maconellicoccus hirsutus (Green), on grapes, releases of C. montrouzieri only help in suppression of the pink hibiscus mealybug on grapes, ber, guava, sapota, custard apple, citrus and hibiscus. The encyrtid parasitoid, Tetracnemoidea indica (Ayyar), was able to check the oriental mealybug, Planococcus lilacinus (Ckll.) on acid lime and pomegranate. The predators, C. montrouzieri and Spalgis epeus Westwood, also play a major role in suppression of P. lilacinus on guava, ber, sapota and chow-chow. The local parasitoid, A. dactylopii was seen to play a major role in suppression of spherical mealybug, Nipaecoccus viridis (Maskell) on citrus and jackfruit. Nevertheless, releases of C. montrouzieri are found highly effective in controlling N. viridis on acid lime and pummelo. Similarly release of C. montrouzieri is found to be highly effective in controlling striped mealybug, Ferrisia virgata (Ckll.), on guava, tuberose and Acalypha in 30-40 days of release. A local parasitoid, Aenasius advena Comp., also plays a major role in suppression of F. virgata on guava, mango, guava, hibiscus, fig, citrus, etc. Release of the coccinellid predator, C. montrouzieri, was found very effective in controlling the mango coccid, Rastrococcus iceryoides (Green) on mango and also on the medicinal plant Decalepis hamiltonii. The encyrtid, Praleurocerus viridis (Agarwal), was found very effective in reducing populations of R. iceryoides on guava. Spalgis epeus was found to be the predominant predator of the papaya mealybug, Paracoccus marginatus Williams and de Granara Willink, but releases of the exotic parasitoid, Acerophagus papayae(Noyes&Schauff), only provide excellent control of P. marginatus within 3-4 months of release. The second successful classical biological control attempt on mealybugs in India. The brinjal mealybug, Coccidohystrix insolita (Green), is known to attack brinjal, Coleus, Hibiscus, etc. Cryptolaemus montrouzieri effectively controlled mealybugs on these three crops in 30-40 days of release. Verticillium lecanii Zimm. (Phule bugicide @ 2g/L) is found to be effective in killing the mealybug. Other fungal pathogens, viz., Beauveria bassiana (Bals.) Vuill and Metarhizium anisopliae (Metch.), are also seen to infect mealybugs in rainy season under humid conditions

Disengagement of the deeply engaged fetal head during caesarean section in advanced labor: patwardhan versus push extraction

Background: To compare the maternal and neonatal morbidities between the “Patwardhan” technique and the “Push” method for extraction of the foetus in second stage caesarean sections.Methods: Retrospective cohort study was done at PESIMSR, Kuppam, AP from MAY 2012 to APRIL 2015. Women with single fetus at term in anterior vertex position, with the head deeply impacted in pelvis and needing cesarean delivery where included in the study.  Group 1 consists of all cases in which extraction of fetus was done by Patwardhan technique and Group 2, in whom extraction of fetus was done by push method and extracted as vertex. Objective of the study was to assess selective complications like extension of the incision, injury to the surrounding structures, excessive bleeding, need for blood transfusion and the fetal outcome between the two groups.Results: Out of 98 cases reviewed, 46 belonged to group A (Patwardhan) and 52 belonged to group B (push). Patients in the push group had statistically significant higher rates of maternal morbidity in terms of uterine extension and other related complications. However; there were no differences in neonatal outcomes in both the groups.Conclusions: While complications are inherent in both methods, Patwardhan method of delivery of the fetus for second stage labour has been shown to confer considerable advantage in prevention of maternal morbidity over the push method in our institution. Our findings support the fact that the Patwardhan method could be a useful maneuver in intraoperative disengagement of fetal head, when encountered at second stage CS and it is our opinion that the Patwardhan manoeuvre can be practiced selectively as a primary technique.

Nap1 regulates proper CENP-B binding to nucleosomes

CENP-B is a widely conserved centromeric satellite DNA-binding protein, which specifically binds to a 17-bp DNA sequence known as the CENP-B box. CENP-B functions positively in the de novo assembly of centromeric nucleosomes, containing the centromere-specific histone H3 variant, CENP-A. At the same time, CENP-B also prevents undesired assembly of the CENP-A nucleosome through heterochromatin formation on satellite DNA integrated into ectopic sites. Therefore, improper CENP-B binding to chromosomes could be harmful. However, no CENP-B eviction mechanism has yet been reported. In the present study, we found that human Nap1, an acidic histone chaperone, inhibited the non-specific binding of CENP-B to nucleosomes and apparently stimulated CENP-B binding to its cognate CENP-B box DNA in nucleosomes. In human cells, the CENP-B eviction activity of Nap1 was confirmed in model experiments, in which the CENP-B binding to a human artificial chromosome or an ectopic chromosome locus bearing CENP-B boxes was significantly decreased when Nap1 was tethered near the CENP-B box sequence. In contrast, another acidic histone chaperone, sNASP, did not promote CENP-B eviction in vitro and in vivo and did not stimulate specific CENP-B binding to CENP-A nucleosomes in vitro. We therefore propose a novel mechanism of CENP-B regulation by Nap1

Misregulation of Scm3p/HJURP Causes Chromosome Instability in Saccharomyces cerevisiae and Human Cells

The kinetochore (centromeric DNA and associated proteins) is a key determinant for high fidelity chromosome transmission. Evolutionarily conserved Scm3p is an essential component of centromeric chromatin and is required for assembly and function of kinetochores in humans, fission yeast, and budding yeast. Overexpression of HJURP, the mammalian homolog of budding yeast Scm3p, has been observed in lung and breast cancers and is associated with poor prognosis; however, the physiological relevance of these observations is not well understood. We overexpressed SCM3 and HJURP in Saccharomyces cerevisiae and HJURP in human cells and defined domains within Scm3p that mediate its chromosome loss phenotype. Our results showed that the overexpression of SCM3 (GALSCM3) or HJURP (GALHJURP) caused chromosome loss in a wild-type yeast strain, and overexpression of HJURP led to mitotic defects in human cells. GALSCM3 resulted in reduced viability in kinetochore mutants, premature separation of sister chromatids, and reduction in Cse4p and histone H4 at centromeres. Overexpression of CSE4 or histone H4 suppressed chromosome loss and restored levels of Cse4p at centromeres in GALSCM3 strains. Using mutant alleles of scm3, we identified a domain in the N-terminus of Scm3p that mediates its interaction with CEN DNA and determined that the chromosome loss phenotype of GALSCM3 is due to centromeric association of Scm3p devoid of Cse4p/H4. Furthermore, we determined that similar to other systems the centromeric association of Scm3p is cell cycle regulated. Our results show that altered stoichiometry of Scm3p/HJURP, Cse4p, and histone H4 lead to defects in chromosome segregation. We conclude that stringent regulation of HJURP and SCM3 expression are critical for genome stability

Quantitative Microscopy Reveals Centromeric Chromatin Stability, Size, and Cell Cycle Mechanisms to Maintain Centromere Homeostasis

The deposited item is a book chapter and is part of the series "Centromeres and Kinetochores" published by the publisher Springer Verlag. The deposited book chapter is a post-print version and has been submitted to peer reviewing. There is no public supplementary material available for this publication. This publication hasn't any creative commons license associated.Centromeres are chromatin domains specified by nucleosomes containing the histone H3 variant, CENP-A. This unique centromeric structure is at the heart of a strong self-templating epigenetic mechanism that renders centromeres heritable. We review how specific quantitative microscopy approaches have contributed to the determination of the copy number, architecture, size, and dynamics of centromeric chromatin and its associated centromere complex and kinetochore. These efforts revealed that the key to long-term centromere maintenance is the slow turnover of CENP-A nucleosomes, a critical size of the chromatin domain and its cell cycle-coupled replication. These features come together to maintain homeostasis of a chromatin locus that directs its own epigenetic inheritance and facilitates the assembly of the mitotic kinetochore.There are no funders and sponsors indicated explicitly in the document.info:eu-repo/semantics/publishedVersio

The Centromere:Chromatin Foundation for the Kinetochore Machinery

Since discovery of the centromere-specific histone H3 variant CENP-A, centromeres have come to be defined as chromatin structures that establish the assembly site for the complex kinetochore machinery. In most organisms, centromere activity is defined epigenetically, rather than by specific DNA sequences. In this review, we describe selected classic work and recent progress in studies of centromeric chromatin with a focus on vertebrates. We consider possible roles for repetitive DNA sequences found at most centromeres, chromatin factors and modifications that assemble and activate CENP-A chromatin for kinetochore assembly, plus the use of artificial chromosomes and kinetochores to study centromere function

Disengagement of the deeply engaged fetal head during caesarean section in advanced labor: patwardhan versus push extraction

Background: To compare the maternal and neonatal morbidities between the “Patwardhan” technique and the “Push” method for extraction of the foetus in second stage caesarean sections.Methods: Retrospective cohort study was done at PESIMSR, Kuppam, AP from MAY 2012 to APRIL 2015. Women with single fetus at term in anterior vertex position, with the head deeply impacted in pelvis and needing cesarean delivery where included in the study.  Group 1 consists of all cases in which extraction of fetus was done by Patwardhan technique and Group 2, in whom extraction of fetus was done by push method and extracted as vertex. Objective of the study was to assess selective complications like extension of the incision, injury to the surrounding structures, excessive bleeding, need for blood transfusion and the fetal outcome between the two groups.Results: Out of 98 cases reviewed, 46 belonged to group A (Patwardhan) and 52 belonged to group B (push). Patients in the push group had statistically significant higher rates of maternal morbidity in terms of uterine extension and other related complications. However; there were no differences in neonatal outcomes in both the groups.Conclusions: While complications are inherent in both methods, Patwardhan method of delivery of the fetus for second stage labour has been shown to confer considerable advantage in prevention of maternal morbidity over the push method in our institution. Our findings support the fact that the Patwardhan method could be a useful maneuver in intraoperative disengagement of fetal head, when encountered at second stage CS and it is our opinion that the Patwardhan manoeuvre can be practiced selectively as a primary technique.