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Key message: Superior F1 mulberry genotypes with high leaf yield, quality, and moderate to high stability were identified for optimal and sub-optimal input conditions. Mulberry (Morus spp.) is a highly heterozygous, perennial tree widely grown for its foliage to feed monophagous silkworms (Bombyx mori L.) and fruits for human consumption across the globe. The present study evaluated twenty-one F1 mulberry genotypes for the selection of superior ones based on leaf yield, yield attributes, leaf quality, and stability over two years under optimal and sub-optimal input (irrigation and fertilizer) conditions. Based on pooled data analysis over four crop seasons, it was found that six mulberry genotypes, D16, D21, D22, D23, D28, and D67, had leaf yields (663–840 g/plant) statistically similar to or better than the Vishala check (663 g/plant) under optimal conditions. Similarly, under sub-optimal conditions, seven genotypes, D16, D21, D22, D23, D24, D28 and D34, showed significantly higher leaf yields (418–596 g/plant) than Vishala (415 g/plant). The δ13C (a surrogate trait of water-use efficiency) of five mulberry genotypes, D16, D21, D24, D28, and D34, varied from – 28.21 to – 28.98 and was similar to the AGB8 check (– 28.87). Total soluble sugar, protein, chlorophyll content, and the silkworm moulting percentage and single larval weight for the seven genotypes D16, D21, D22, D23, D24, D28, and D34 were statistically similar to or better than Vishala under both optimal and sub-optimal conditions. The additive main effects and the multiplicative interaction-based simultaneous selection index showed that these seven genotypes had moderate to high stability and high leaf-yielding ability over the seasons under both optimal and sub-optimal conditions. DNA fingerprint profiles of these selected genotypes have been developed for their molecular identification. Under this context, these seven genotypes might be further tested under advanced evaluation trials to identify the best one regarding leaf yield and quality under optimal and sub-optimal conditions. [ABSTRACT FROM AUTHOR]

This study developed three transgenic mulberry lines containing heterologous phosphoenol pyruvate carboxylase gene of Flaveria trinervia through Agrobacterium tumefaciens-mediated genetic transformation using cotyledon and hypocotyl explants of mulberry cv. G4. These transgenic lines had 1–1.56-fold expression of the phosphoenol pyruvate carboxylase gene of Flaveria trinervia, regulated by a constitutive promoter. The phosphoenol pyruvate carboxylase activity in transgenic mulberry lines enhanced upto 1.91 to 2.66-fold compared to wild-type plants. Transgenic mulberry lines exhibited significantly higher photosynthetic rate, improved instantaneous water use efficiency, stomatal conductance, transpiration rate, relative water, and proline content than the WT plants under 60% field capacity. Leaf discs assay of transgenic lines revealed less chlorophyll degradation and electrolyte leakage than those in wild-type plants under 25% polyethylene glycol (molecular weight > 6000) and 200 mM NaCl. In this study, for the first time, transgenic mulberry lines expressing the phosphoenol pyruvate carboxylase gene of Flaveria trinervia were developed, which showed improved photosynthesis rate with tolerance to drought and salinity stresses. These transgenic mulberry lines developed in this study could be further tested in a confined field trial to evaluate their leaf yield, yield attributes, leaf quality, and physiological parameters under irrigated and sub-optimal irrigation/drought stress conditions. These transgenic lines could be used as pre-breeding resources in mulberry breeding programs in the future.Key message: Transgenic mulberry lines were developed by introducing the PEPC gene of Flaveria trinervia through Agrobacterium-mediated genetic transformation, and the transgenic lines showed improved gas exchange parameters, tolerance to abiotic stresses. [ABSTRACT FROM AUTHOR]

Key message: An efficient, high-frequency, and robust in vitro regeneration protocol was developed using cotyledon and hypocotyl explants from mulberry (Morus indica cv. G4) seedlings. Mulberry (Morus) is a perennial tree species with a wide range of commercial applications. Its leaves are predominantly used for feeding the monophagous silkworm (Bombyx mori L.) globally. In this study, the effects of plant growth regulators, additives and elevated levels of macronutrients, on in vitro adventitious shoot induction, shoot elongation, and rooting, were investigated. It was found that modified Murashige and Skoog (MS) medium supplemented with thidiazuron (0.5 mg/L) provided the most suitable medium for adventitious shoot bud induction, with a regeneration frequency of 88.62%, and yielded adventitious shoot buds of 10.60 ± 0.30 per cotyledon explant. Additionally, the MS medium fortified with 6-benzylaminopurine (1.0 mg/L), gibberellic acid (1.5 mg/L), silver nitrate (2 mg/L), putrescine dihydrochloride (1 mg/L), activated charcoal (AC, 0.2%), and supplementary dosage of calcium chloride (515 mg/L) resulted in the highest frequency of shoot elongation, spontaneous root induction, and the longest shoot length. In this medium, no hyperhydricity of regenerated shoots/leaves was observed. We observed the longest adventitious root length and secondary root length of the shoots grown on MS medium supplemented with indole-3-butyric acid (2 mg/L) and AC (0.2%). The frequencies of ex vitro survival of plantlets after hardening were 90–95% and 95–100%, under laboratory and field-like conditions, respectively. Even though in vitro regeneration protocol in mulberry is genotype-dependent and explant-specific, the robust regeneration protocol developed in this study could find its applications in genome editing and genetic transformation using cotyledon and hypocotyl explants of other cultivars. [ABSTRACT FROM AUTHOR]

Correction to: In vitro regeneration of mulberry plants from seedling explants of Morus indica cv. Correction to: Trees https://doi.org/10.1007/s00468-021-02186-9 The table 1 has been published with corrections in the original publication. [Extracted from the article]

Bacterial leaf spot incited by Xanthomonas campestris pv. mori is a devastating foliar disease of mulberry reported globally. Host plant resistance is the most sustainable and economic control measure but so far unexplored. Highly heterozygous plant behaviour and scant genetic information of bacterial leaf spot resistance limits a targetted breeding approach in mulberry. In the present research eight pseudo-F(F)full-sib progenies derived from selected resistant and susceptible sources were evaluated symptomatically for bacterial leaf spot resistance under natural disease occurrence in 2008 and 2009. Significant variation for bacterial leaf spot resistance was observed in the parents and progenies. Broad sense heritability estimate (0.9) indicates that selection of resistant genotypes can be useful for exploitation in future advanced breeding programs for mulberry. High narrow sense heritability estimates (0.76)[2008] and (0.79)[2009] suggest additive gene effects for the disease resistant trait. The continuous frequency distribution of diseases severity across the progenies indicates that bacterial leaf spot resistance in mulberry may be inherited quantitatively. [ABSTRACT FROM AUTHOR]

Sericulture is an agro-based industry, which heavily depends on mulberry ( Morus spp.) for its sustainability, as mulberry leaf is the only available feed for the silkworm Bombyx mori L. Sericulture, in West Bengal and other subtropical regions in India, suffers from lack of adequate quantity of quality mulberry leaf during the colder months, the best season for rearing the high yielding bivoltine silkworm hybrids. In order to develop mulberry varieties, which can sustain normal growth during these colder months to yield better, efforts have been made in different research institutes in India. The present report is part of such an effort in which accessions in germplasm bank were screened for better growth, leaf retention and leaf yield contributing associated traits. Twenty three selected parents were crossed, 3,500 seeds were sown, 2,700 seedlings were transplanted to progeny row trail, selected 210 hybrids were evaluated under primary yield trial and finally nine hybrids along with a control variety were studied in detail for all leaf yield contributing traits under final yield trial. Stability analysis was adopted to identify hybrids, which can yield stably across seasons. The hybrids CT-44 and CT-11 out yielding the control by 17.17 and 7.11% were selected as these hybrids yield 7.93 and 8.15 mt/ha leaf respectively during the colder months (February) for their direct use as cultivars in West Bengal and other subtropical areas of India to sustain bivoltine sericulture to produce quality and gradable silk fibers. [ABSTRACT FROM AUTHOR]

Powdery mildew caused by the ascomycete Phyllactinia guttata (syn. P. corylea) is a major foliar disease worldwide of the unique mulberry ( Morus spp.) for silkworm feed. Genetic resistance to powdery mildew, the most sustainable and economical strategy for disease control, is still elusive for tropical mulberry. About 147 germplasm sources, representing 18 countries of origin, were screened for resistance to P. guttata in six seasonal fields and greenhouse trials after exposure to natural and artificial inoculum, respectively. In the field, the level of plant responsiveness to disease was assessed from 30 to 62 days after pruning in each season as variations in the disease severity index (DSI), disease incidence (DI%) and area under the disease progress curve (AUDPC). These measures differed significantly among the germplasm. Of 147 germplasm sources, ~6.8% had useful resistance (two high and nine moderately resistant) to the powdery mildew pathogen on the basis of DSI. The AUDPC values were 13.5-fold higher in the most susceptible accession—(Philippines) than the least responsive (Vietnam-2). The results of DSI were strongly correlated with the obtained DI values ( r = 0.92; P < 0.01) and AUDPC ( r = 0.89; P < 0.01). Moreover, field screening results were highly correlated ( R2 = 0.839) with values from the greenhouse evaluation using artificial inoculum. However, the DSI values in field and greenhouse screenings for three sources (Non-nayapati, Nao-khurkul and Tista Valley) varied significantly. A relatively low disease reaction of 09 resources (Vietnam-2, Ankara and 07 others) using different assessment scales after natural and artificial inoculation prove, for the first time, that they have potential in breeding for resistance in tropical mulberry to powdery mildew. [ABSTRACT FROM AUTHOR]

Soil salinity is one of the major abiotic stresses that reduce agricultural productivity. The levels of salt concentration that are inimical to plant growth have already affected more than one-third of the irrigated land in the world. In order to utilize the vast saline costal lands present in sericulturally important countries in Asia, attempts have been made to develop salt resistant varieties in mulberry. Controlled crosses were made between salt resistant parents that were identified through both in vitro and in vivo screening. Ripened fruits were harvested, and the seeds extracted were germinated on agar-agar containing MS basal medium with 1.25% NaCl. Young seedlings were rescued and nurtured under normal growth conditions. Mature seedlings were transferred to field. Based on comparative performance on survival and growth under salinity, three hybrids namely SR1, SR2 and SR3 were selected and were subjected to detailed investigation using C776 as control. SR3 outperformed other hybrids and the control, hence, was selected for large scale field testing. The encouraging results have tremendous implications on expanding sericulture industry into the costal saline areas in tropical and subtropical regions in Asia. [ABSTRACT FROM AUTHOR]

The levator ani muscle (LAM), unlike other striated muscles has resting myoelectric activity, the cause of which is not precisely known. In a recent study this activity was suggested to be related to the presence of smooth muscle bundles in the LAM. The present study investigated this point in 25 cadaveric specimens (10 neonates, 15 adults). Histologic examination of the LAM was performed in 12 specimens, three to six slices being taken from the lateral to the medial side of each muscle, processed and stained with H&E and Masson’s trichrome stain. The remaining 13 specimens were studied by direct dissection and photographed. Microscopic examination of specimens from adult cadavers showed that the lateral part of the LAM consisted of purely skeletal muscle bundles, mostly of the small-caliber type and few of the large or intermediate type. As we proceeded medially, smooth muscle bundles started to appear. Examination of slices medial to the midportion of the LAM showed that the muscle began to be separated into two layers: a deep (pelvic) one formed of smooth fibers and a superficial (perineal) one of skeletal fibers, separated by a neurovascular plane. Microscopic examination of specimens from neonates showed that the whole LAM consisted of skeletal fibers; no smooth fibers or separation into two layers were identified. By direct dissection of the adult specimens the medial part of the LAM consisted of two layers, superficial and deep, which were separated by fascia containing vessels and nerves. The muscle was thicker at its medial part and tapered laterally, with loss of demarcation, into two layers. Specimens from neonates showed no differentiation of the LAM, into two layers. It is suggested that the deep layer of the LAM, which was formed of smooth fibers, acts involuntarily, supporting the pelvic viscera by its tone and responding to variations in intra-adominal pressure by adaptation of this tone. The superficial layer of the LAM, made of skeletal fibers, appears to represent the functional mobile part that acts voluntarily during urination or defecation. The presence of the smooth fibers in the adult LAM and not in neonates seems to be adaptational, caused by the action of intra-abdominal pressure and visceral weight. The skeletal fibers pass into various histologic stages before they transform to smooth fibers. [ABSTRACT FROM AUTHOR]

The existence of a sphincter at the rectosigmoid junction (RSJ) is controversial. Recent studies have demonstrated a high-pressure zone within the RSJ which responds to sigmoid colon or rectal contractions by relaxation or contraction, respectively. These findings suggest the presence of a ”physiological” sphincter at the RSJ. The current study investigated the anatomical and histological structure and the radiological picture of the RSJ in view of the possible existence of an anatomical sphincter at the RSJ and elucidating its function. The RSJ was studied in 28 cadavers (18 adults and 10 fully mature neonates) by dissection. A histological study of the RSJ was performed in 5 cadavers. Radiological examination using double-contrast barium enema was carried out in 50 healthy volunteers (mean age 44.2±14.4 years; 32 men, 18 women). The mucous membrane of the RSJ was found in folds forming a ”mucosal rosette” of a mean length of 2.8±0.9 cm in adult specimens and 0.7±0.2 cm in neonates. The distal end of the mucosal rosette was sharply delineated and in some specimens protruded into the rectal lumen as a small nipple, which was surrounded by a ”rectal fornix” on either side. The histological examination of the RSJ showed mucosal foldings with deep crypts surrounded by lymphocytic aggregates and marginated by muscularis mucosa. The circular muscle coat showed gradually increasing thickness towards the rectum. Nerve cells in the submucosa were located at three levels: in the vicinity of the muscularis mucosa, in the middle of the submucosa, and in the proximity of the circular muscle. Radiologically the opening of the sigmoid colon into the RSJ presented as a ring or crescent. Radiological striations representing the mucosal rosette were demonstrated. The RSJ appeared as a narrow contractile segment. The anatomical, histological, and radiological findings thus indicate that the RSJ is a segment which can be identified by its interior rather than outer aspect. The study suggests the presence of an anatomical sphincter at the RSJ which seems to regulate the passage of stools from the sigmoid colon to the rectum. [ABSTRACT FROM AUTHOR]

A technique for the reduction of state sensitivity of distributed control systems to small parameter variations is studied. The particular case of systems governed by linear parabolic evolution equations is considered. The initial control problem is transformed to an augmented one defining state and control sensitivities. An augmented cost function is introduced by adding terms in these sensitivities. Two cases for the new cost function are discussed and some numerical results are given. [ABSTRACT FROM AUTHOR]

Control systems governed by linear parabolic partial differential equations are considered. A new technique for the reduction of the state sensitivity to small parameter variations is presented. A new cost function, which does not depend on the parameter, is defined. The corresponding optimal control is obtained in an open-loop form, then it is transformed into a feedback form so that a better reduction of the sensitivity is guaranteed. A simple example illustrates the application of the technique. [ABSTRACT FROM AUTHOR]

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Copyright of Kolloid-Zeitschrift und Zeitschrift für Polymere is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The relevance of KRAS mutation alleles to clinical outcome remains inconclusive in pancreatic adenocarcinoma (PDAC). We conducted a retrospective study of 803 patients with PDAC (42% with metastatic disease) at MD Anderson Cancer Center. Overall survival (OS) analysis demonstrated that KRAS mutation status and subtypes were prognostic (p < 0.001). Relative to patients with KRAS wildtype tumors (median OS 38 months), patients with KRAS G12R had a similar OS (median 34 months), while patients with KRAS Q61 and KRAS G12D mutated tumors had shorter OS (median 20 months [HR: 1.9, 95% CI 1.2-3.0, p = 0.006] and 22 months [HR: 1.7, 95% CI 1.3-2.3, p < 0.001], respectively). There was enrichment of KRAS G12D mutation in metastatic tumors (34% vs 24%, OR: 1.7, 95% CI 1.2-2.4, p = 0.001) and enrichment of KRAS G12R in well and moderately differentiated tumors (14% vs 9%, OR: 1.7, 95% CI 1.05-2.99, p = 0.04). Similar findings were observed in the external validation cohort (PanCAN's Know Your Tumor® dataset, n = 408)., (© 2024. The Author(s).)