Nirmal Mandal

In vitro accelerated mass propagation and ex vitro evaluation of Aloe vera L. with aloin content and superoxide dismutase activity

An innovative protocol on accelerated in vitro propagation and acclimatisation was developed in Aloe vera L. Culture was initiated with rhizomatous stem where Murashige and Skoog (MS) medium fortified with 0.5 mg L−1 α-naphthalene acetic acid and 1.5 mg L−1 N6-benzylaminopurine (BAP) promoted earliest shoot induction. Maximum shoot multiplication was achieved in MS medium supplemented with 2.5 mg L−1BAP. The best in vitro rooting was observed in the MS medium with 0.5 mg L−1 indole-3-acetic acid plus 2 g L−1 activated charcoal. The simple acclimatisation process, primarily with a combination of sand and soil (1 : 1 v/v) and finally with a blend of sand, soil and farm yard manure (2 : 1 : 1 v/v), ensured a 98% survival rate. Overall, 192 true-to-type plantlets were achieved from a single explant within 85 days. Morphologically, in vitro generated plants performed better than conventionally propagated plants; nevertheless the similarity in aloin content, gel content and superoxide dismutase activity was corroborated.

Stevia: A Comprehensive Review on Ethnopharmacological Properties and In Vitro Regeneration

The present review illustrates the pharmacological properties and production of planting materials through in vitro organogenesis of Steviarebaudiana (Bertoni). The plant is native to Paraguay; however, the main producers of stevia are Japan, China, Taiwan, Thailand, Korea, Brazil, Malaysia and India. This plant is recorded as having a non-caloric natural sugar, alternative to artificially produced sugar substitutes and hence traditionally has been used to sweeten beverages. This article enumerates an overview on pharmacological and micropropagation aspects which are of use to researchers for further exploration for the indispensable improvement of this potential herb with medicinal importance.

Cisgenics - a sustainable approach for crop improvement.

The implication of molecular biology in crop improvement is now more than three decades old. Not surprisingly, technology has moved on, and there are a number of new techniques that may or may not come under the genetically modified (GM) banner and, therefore, GM regulations. In cisgenic technology, cisgenes from crossable plants are used and it is a single procedure of gene introduction whereby the problem of linkage drag of other genes is overcome. The gene used in cisgenic approach is similar compared with classical breeding and cisgenic plant should be treated equally as classically bred plant and differently from transgenic plants. Therefore, it offers a sturdy reference to treat cisgenic plants similarly as classically bred plants, by exemption of cisgenesis from the current GMO legislations. This review covers the implications of cisgenesis towards the sustainable development in the genetic improvement of crops and considers the prospects for the technology.

Artificial polyploidy in medicinal plants: Advancement in the last two decades and impending prospects

Medicinal plants are in huge demand since the consumption is widespread and ever-increasing globally. The conventional breeding programs are generally environmental dependent; prone to different biotic and abiotic stresses as well as the secondary metabolite content is too low to harvest. In this context, developing polyploid individuals artificially would be a remarkable approach to increase vigor and attain this objective. Polyploids often exhibit some morphological features that are different or greater in forms than their diploid progenies. Polyploidization can be induced by quite a few antimitotic agents. The most frequently used antimitotic chemicals are colchicine, trifluralin, and oryzalin. The whole method of induced chromosome doubling consists of a series of steps, including an induction phase, regrowth phase, and a confirmation technique to evaluate the rate of achievement. The induction phase depends on different factors, such as explant types, antimitotic agents, its different concentrations, and exposure durations. To evaluate the accomplishment of polyploidization, morphological or anatomical observations are recorded as a rapid method. However, chromosome count and flow cytometry are the most eminent method for absolute confirmation. Despite significant prospects of polyploidization, there has been very little research on medicinal plants. The current review gives an overview of the different parameters of in vitro chromosome doubling, the history of the technique, and progress made over the last two decades.

Single Nucleotide Polymorphism (SNP) Marker for Abiotic Stress Tolerance in Crop Plants

Agricultural crop production has been seriously hampered by various detrimental environmental conditions all over the world. Such conditions modify the growth and development of plants and ultimately reduce the economic yield enormously. These detrimental effects can be overcome by developing better stress-tolerance plants utilizing different genetic techniques. Therefore, there is a need to develop a marker system for the identification of stress responsive genes in order to combat the losses. Single nucleotide polymorphisms (SNPs) have become a more preferable marker over microsatellites because of their frequent occurrence in the genome and low rate of mutations. The discovery of SNPs in many crop species facilitates the availability and identification of many genes or quantitative trait loci (QTLs) associated with traits related to abiotic stress. Hence, identification of SNP flanking the genomic regions containing QTLs for aspects of abiotic stress tolerance would strongly expedite the targeted integration of this trait into another susceptible germplasm. Such identification of SNPs will not only promote marker-assisted breeding for abiotic stress tolerance but also open a vista for cloning and evaluation of primary genetic factors suitable for engineering improved abiotic stress tolerant plants. This review presents the present status of SNP marker technologies for abiotic stress tolerance in crop plants.

Mapping of molecular markers linked with MYMIV and yield attributing traits in mungbean

The present study employed recombinant inbred lines (RILs) derived from the cross between a susceptible cultivar Sonali and resistant wild relative of mungbean (Vigna radiata var. sublobota to map molecular markers linked with mungbean yellow mosaic Indian virus (MYMIV) resistance and yield attributing traits in mungbean. Resistance to the virus was evaluated in RIL population under field conditions during two consecutive years 2013 and 2014. A set of 224 molecular markers were employed for the identification of polymorphism between parents. Only 46 markers showed polymorphism between Sonali and V. radiata var. sublobota. Twenty two polymorphic markers were used to construct a linkage map comprising 11 linkage groups. QTL analysis identified molecular markers linked with MYMIV resistance and agronomic traits viz., no. of pods per plant, no. of seeds per pod and 100seed weight. Molecular markers identified to be linked with MYMIV were confirmed in 93 diverse mungbean accessions screened for yellow mosaic disease. The molecular markers linked to the MYMIV and yield attributing traits identified in this study will be useful in marker assisted breeding for development of high yielding mungbean varieties resistant to MYMIV.

Analysis of seed storage protein diversity among twelve different cultivars of Pea (Pissum sativum L.) using SDS-PAGE.

The present investigation was carried out during 2012-13 with twelve Pea ( Pisum sativum L.) cultivar for protein profiling through SDS-PAGE in The department of Genetics and Plant Breeding, CSA University of Agriculture and Technology, Kanpur (U.P). The Seed protein profiles of pea cultivars were studied by extracting the total proteins from five single seeds in each cultivar and performed SDS-Polyacrylamide gel electrophoresis. All the cultivars were clearly revealed remarkable polymorphism from their protein banding patterns. On the basis of banding patterns through SDS-PAGE, indicated that the number of bands found in cultivars ranged from 12 to 19 with Rm value 0.12 to 0.9. The results found that, the cultivar KPMR-400 had recorded highest number of bands (19) whereas, the minimum number of bands (12) observed in three cultivars viz., KPMR-921, KPMR-902 and KPMR-913. The total seed protein variation were also analyzed using Un-weighted Pair Group Method with Arithmetic Mean (UPGMA) and resultant cluster analysis based on the data of protein profiling, classified twelve cultivars into six major groups. The finally study concluded that, the protein variability analysis clearly showed that there was sufficient genetic divergence among these cultivars of pea with respect to seed storage protein. Among all the cultivars, the KPMR-906 in cluster IV having wider genetic diversity and suggested to utilize in future crop improvement program.

Inheritance of MYMIV tolerance in two RIL populations of greengram on lower Gangetic alluvial zone during summer and their parental molecular diversity

Inheritance of MYMIV tolerance was determined in two sets of recombinant inbred lines (RILs) of mungbean. The two sets comprising 143 and 79 RILs each derived from the cross between PM5 x Sub2 and B1 X Sub2, respectively were considered for the study. Sub2 was a Sublobata derived lines whereas, B1 was a popular small seeded cultivar of west Bengal, susceptible against MYMIV. It was observed that one or two major genes with a few modifiers played a significant role in resistance mechanism against MYMIV in the lower Gangetic alluvial zone. Resistance alleles for Sub2 and PM5 are probably allelic as observed from frequency distribution pattern. A set of 177 SSRs were employed for identification of polymorphism between parents. Only 37 SSRs showed polymorphism between Sublobata and B1 or PM5. But only eight SSRs were polymorphic between two high yielding cultivars. Markers linked with MYMIV tolerance like RGA, SCAR and others from earlier studies were also considered and found that only one RGA derived marker showed polymorphism between resistance and susceptible parents.