8,525 research outputs found
SyBrid - A New Breeding Method for Food Legumes
Legumes in general, are grown under subsistence agriculture and their productivity is invariably low. Being predominantly a self –pollinated group of crops, only inbred cultivars were bred in the past with marginal yield advantages. An alternate breeding method has been proposed that is capable of exploiting part of hybrid vigour to improve yield potential of some legume crops without any serious seed production hassle. The breeding product, named “SyBrid”, is an amalgam of the concepts of breeding synthetic and hybrid cultivars. It uses natural cross-pollination but no male sterility system. Potentially, the “SyBrid” cultivars are expected to boost yield by a margin of 10-15% or more. The seed production of “SyBrid” cultivars is cost effective and easy
Can a speed breeding approach accelerate genetic gain in pigeonpea?
Pure line breeding is a resource-intensive activity that takes 10 years or more to develop a new cultivar. In some crops, conducting off-season nurseries has significantly reduced the length of the breeding cycle. This approach could not be exploited in pigeonpea [Cajanus cajan (L.) Millsp.], because traditionally it has been a photoperiod-sensitive crop that requires long periods of darkness to induce flowering. However, the recent success of breeding early maturing photoperiod-insensitive genotypes has opened up the possibility of adopting ‘speed breeding’ techniques to enable rapid generation turnover. This paper outlines a speed breeding approach that integrates the use of immature seed germination for rapid generation advancement and a "single pod descent" method of breeding. To accelerate line development, while conserving genetic variability, the approach permits four generations per year and can fast-track field evaluation of resulting homozygous lines. Therefore, the breeding strategy conserves resources and has potential to deliver new early maturing cultivars within a substantially reduced timeframe of 4–5 years
Can pigeonpea hybrids negotiate stresses better than inbred cultivars?
Pigeonpea [Cajanus cajan (L.) Millsp.] is an important rainfed pulse crop of tropics and sub-tropics, and
during its long growth cycle of 6–9 months it encounters a number of biotic and abiotic stresses. The recently
developed CMS-based pigeonpea hybrids have demonstrated large gains in yield and stability over the traditional
inbred cultivars. In this review, the authors argue that the heterosis expressed in traits like seed germination,
radicle growth, root biomass production and moisture retention during water stress confers advantages
to hybrid plants in negotiating a few abiotic and biotic stresses in much better way than pure line cultivars
Enhanced MHC I antigen expression on tumour target cells is inversely correlated to lysis by allogenic but not by xenogenic NK cells
Relationship between the levels of MHC class 1 antigen expressed on tumour cells and their susceptibility to allogenic and xenogenic NK cells was investigated. Mouse and human natural killer-resistance inducing factor (NK-RIF) preparations were used for augmenting/inducing MHC 1 antigen expression on murine YAC and human K562 tumour cells, respectively YAC cells with augmented MHC I antigen expression became relatively resistant to lysis by murine NK cells but not to rat NK cells. Similarly, induction of MHC I antigens on K562 cells reduced their susceptibility to human NK cells but not to monkey NK cells. These results indicate that the inverse correlation of MHC I antigen expression and NK susceptibility does not hold true for xenogenic pairs of NK effector and target cells
The glass transition and crystallization kinetic studies on BaNaB9O15 glasses
Transparent glasses of BaNaB9O15 (BNBO) were fabricated via the conventional
melt-quenching technique. The amorphous and the glassy nature of the
as-quenched samples were respectively, confirmed by X-ray powder diffraction
(XRD) and differential scanning calorimetry (DSC). The glass transition and
crystallization parameters were evaluated under non-isothermal conditions using
DSC. The correlation between the heating rate dependent glass transition and
the crystallization temperatures was discussed and deduced the Kauzmann
temperature for BNBO glass-plates and powdered samples. The values of the
Kauzmann temperature for the plates and powdered samples were 776 K and 768 K,
respectively. Approximation-free method was used to evaluate the
crystallization kinetic parameters for the BNBO glass samples. The effect of
the sample thickness on the crystallization kinetics of BNBO glasses was also
investigated.Comment: 23 pages, 12 figure
Arresting Soil Erosion in Hilly Terrains with Pigeonpea - The Chinese Experience
Conservation of the nutrient-rich top soil is extremely important for sustaining agricultural productivity. It is now becoming a serious crop production constraint, particularly in the slopping hilly terrains. The ecology of such areas is rapidly deteriorating and their recovery seems extremely difficult. In southern China, where soil erosion is a serious issue, various plant species were unsuccessfully tried in the past to arrest the soil erosion. The Chinese scientists, in collaboration with ICRISAT, used late maturing pigeonpea cultivars to protect the fragile lands in Guangxi and Yunnan provinces. The planted area under pigeonpea in this system rapidly increased to 700 ha by 2001. This paper summarizes the methodologies used in soil conservation practices involving pigeonpea
Non-fusion joining of aluminium
JOINING of aluminium is now a well established techn-ology. Successful joining can be done by TIG and MIG welding, pressure welding processes, brazing and solde-ring processes. Conventional fusion processes of joining aluminium are well known and are widely used in India by all major fabricators. On the other hand, though non-fusion joining processes like soldering, brazing and pressure welding have wide field of applications the correct process and material required are not very well known ; as such there is a specific need in India, at present, to disseminate the knowledge on joining of aluminium especially by these processes which a small fabricator can handle
Partial purification and characterization of a novel human factor that augments the expression of class I MHC antigens on tumour cells
A cytokine which augments the expression of major histocompatibility complex (MHC) I antigens on K562 and gastric carcinoma tumour (HR) cells, has been isolated from the culture supernatant of Concanavalin-A (Con-A) activated human peripheral blood mononuclear cells. The factor, termed MHC augmenting factor (MHC- AF) has been partially purified by Sephadex G- 100 column chromatography, preparative isoelectric focusing and HPLC with ion- exchange as well as sizing columns. MHC-AF activity is associated with a 35 kDa molecule which has pI of 6.0. Interferon (IFN)-α, β, tumour necrosis factor (TNF), Interleukin (IL)-2, IL-4, IL-5 and IL-7 had no significant effect in MHC- AF bioassay, but IFN-γ had significant MHC-AF activity. Antibodies to IFN-α , IFN-β and TNF-α did not block the activity of MHC-AF, but anti-IFN-y antibodies could partially neutralize the activity. However, unlike IFN-γ , MHC-AF activity was resistant to pH 2.0 treatment. Purified MHC-AF preparations did not have any activity in WISH cell/encephalo myocarditis virus (EMC) IFN bioassays. In addition, anti-IFN-y affinity column did not retain MHC-AF activity. These results indicate that a MHC-AF distinct from IFN-γ, is produced by activated human mononuclear cells
Extrahepatic undifferentiated embryonal sarcoma, cytology as an accurate method for early diagnosis: an extremely rare case report in an Indian child
Undifferentiated embryonal sarcoma has been described in the liver, a rare malignant mesenchymal neoplasm, that occurs primarily in children and teenagers. Approximately 260 cases have been reported arising in the liver since 1978 when this disease was first described. Its pathogenesis is still obscure. Authors presented a case of extrahepatic undifferentiated embryonal sarcoma in a 9-year-old female presenting with upper abdominal dull pain. Ultrasound and CT Scan showed normal liver architecture, with liver pushed upwards due to compression by tumor arising in the retroperitoneum. To the best of our knowledge, this is first case of extrahepatic undifferentiated embryonal sarcoma diagnosed on cytomorphology and confirmed by histopathology and immunohistochemistry markers
- …