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The genus Brassica is one of the most important oil seed crops in India with high degree of genetic diversity. In present study, genetic diversity was studied in forty germplasm lines and eight cultivars of Indian mustard using morphological traits and SSR markers. Morphological characters were taken for days to 50% flowering, days to maturity, plant height (cm), length of main raceme (cm), number of primary branches/plant, number of secondary branches/plant, number of silique per plant, number of seeds per silique, 1000 seed weight (g) and seed yield per plant (g). Total 50 SSR markers were used for characterization of these lines, out of which 7 SSR markers were highly polymorphic between all the germplasms of mustard. An UPGMA phonogram was constructed for all 48 Germplasms and the similarity coefficient ranged from 0.00 to 0.91. Number of alleles ranged from 3 to 4, genetic diversity ranged from 71% to 65% with average value of 67%, heterozygosity raged from 20 to 10% with average of 12% and PIC value for markers ranged from 0.65 to 0.59 with mean PIC value 0.61. All seven SSR primers showed PIC value above 0.5 (50%) indicating high genetic diversity in the studied plant material.

Background: Groundnut (Arachis hypogaea L.) is one of the most nutritious crops having versatile use. Its yield is mostly exaggerated by two foliar fungal diseases i.e., early and late leaf spot. In present investigation 96 germplasm lines were screened for early and late leaf spot diseases along with diverse biochemical parameters including protein, oil, fatty acids, proline and sugar contents. Methods: Early and late leaf spot diseases have been screened under field condition as well as employing SSR molecular markers. Nutritional profiling has also been done for protein, oil, fatty acids viz., oleic acid, linoleic acid, stearic acid and palmitic acid, proline and sugar contents. Result: In correlation analysis, oleic acid is negatively correlated with linoleic acid (r= -0.911) and palmitic acid (r= -0.688) at 1% level of significance, whereas stearic acid is positively and highly significantly correlated with oil percentage (r=0.381) at 1% significance level. The gene diversity value varied between 0.1866 to 0.4837 for markers ipahm103 and GM1536 with an average of 0.4014 and polymorphic information content (PIC) values ranged between 0.1692 to 0.3855 for the markers pahm103 to GM1536 respectively with a mean value of 0.3183.

Rauvolfia serpentina is an erect evergreen, woody perennial shrub and usually recognized as Sarpgandha Main institutes of sarpgandha roots are reserpine, rescinnamine, deserpidine and yohimbine and the root part of the plant is employed in several Ayurvedic polyherbal formations viz., sarpgandha vati. When efficient and reproducible plant regeneration systems are available, in vitro culture is an important experimental tool in medicinal and aromatic crops. Experiments were carried out to quantify secondary metabolite production in Rauvolfia serpentina from filtrate of callus and cell suspension cultures. Reserpine and ajmalicine were found infiltrate of both one-month-old callus and cell suspension cultures. The culture medium MSD.5IB (MS+1.0 mgl-1 2,4-D + 0.5 mgl-1 IBA) recovers the most reserpine content in both callus and cell suspension cultures after one month. The amount of reserpine in a liquid medium decreased dramatically as the concentration of 2,4-D in the medium increased. When the concentration of 2,4-D was increased, the concentration of Ajmalicine in both callus and cell suspension cultures decreased linearly. These products may be further produced in commercial scale in bioreactor by using raw biomolecules for commercial purposes.

Groundnut (Arachis hypogaea L.) is an excellent cash crop having multipurpose uses of each plant part i.e., direct consumption, cooking oil and a rich source of protein feed for animals. Rust and late leaf spot (LLS) are two major foliar fungal diseases of groundnut and can cause yield loss up to 70%. Use of fungicide is costly approach and it is not environment-friendly also, therefore breeding new cultivars with genetic resistance is sustainable, environment-friendly and cost effective approach. Screening and identification of resistant cultivar is one of the primary objective for groundnut improvement. Use of molecular markers, particularly gene based, are user friendly and cost effective approach to identify groundnut resistant genotypes. The present investigation aimed to screen groundnut germplasm using allele specific primers for foliar fungal diseases (LLS and rust). The study consisted 30 uncharacterized germplasm lines and 4 check varieties of Groundnut. A set of 4 gene based SSR markers were selected for screening of groundnut germplasms for foliar fungal diseases i.e., LLS and rust. A total of 14 alleles were identified with an average of 3.5 alleles per locus for polymorphic SSR markers. The gene diversity and Polymorphic Information Content (PIC) values varied between 0.3972-0.5778 with an average of 0.47 respectively. The genetic relationships among Groundnut genotypes are presented in SSR based UPGMA tree. Principle Co-ordinate analysis (PCA) based on origin formed 4 major population groups. The population structure of the 34 Groundnut genotypes was estimated using STRUCTURE v2.3.3 software based on SSR markers. The optimum K value was determined by using Structure Harvester, where the highest peak was observed at delta K = 2. The number of sub populations (K) was identified based on maximum likelihood and delta K (dK) values, with two core and pure groups and an admixture group. Current study identified four germplasms i.e., AH8054, CS21181, CS708, Akola White to be used as foliar disease resistant cultivar for groundnut hybridization and improvement.

Plant breeding is mainly concerned with genetic improvement of crops through hybridization, screening and selection of advance lines. The conventional methods give advance varieties with desirable traits but take consume more time (6 to 12 years) to achieve. Biotechnology tools makes breeding methods more advance by reducing the time to get improved varieties. Other than conventional methods varietal advancement can be achieved by applying plant tissue culture, transgenic approaches and molecular breeding methods. Crop improvement by using biotechnology approaches is mostly concerned with protoplast fusion to get somatic hybrids, gene transfer to get genetically modified organisms and use of DNA markers to select trait of interests. Variety with improved biotic and abiotic stress resistance can be developed in less time and more accuracy using recent biotechnological approaches. Several advance tools are being utilized for that purpose including, nanotechnology, bioinformatics tools offers new era of genomics assisted molecular breeding. Next Generation Sequencing and high throughput genotyping approaches are increasing efficiency and output of biotechnological tools in agriculture. Current review focused on overview of biotechnological tools being applied for crop improvement.

Background: Soybean is an important leguminous crop. Abnormal weather has played an enormous role in the strident decline in crop yields. Drought is considered as a significant abiotic factor responsible for yield reduction in soybean. Methods: The present work was carried out in order to screen soybean genotypes for their drought tolerance ability by means of different biochemical and antioxidant enzymatic activities responses. Conclusion: On the basis of biochemical parameters and anti-oxidant enzymatic activities, soybean genotype viz., RVS-211-77, RVS-211-75, NRC-7, SL-96, NRC-136, AMS100-39, SL-96, RVS-2012-01, RVS-211-73 and JS97-52 have been identified with better performance and can be used as parents for further crop improvement programme to breed drought tolerant variety.

Background: Resistance to foliar fungal diseases along with oleic acid trait, are important objectives of groundnut breeding. Among foliar fungal diseases, rust and Late Leaf Spot (LLS) cause significant economic loss and high oleic trait is preferred in industry that enhances economic values of crop. Methods: Morphological characterization of the 186-groundnut germplasm lines/genotypes for ten yield attributing traits and their significance of correlation was analyzed using SPSS ver. 19 software at 1% and 5% probability level of significance. Screening for LLS and rust diseases was done employing 10X SNP assay at ICRISAT, Hyderabad, India. Selected superior groundnut germplasm line(s) were screened for presence of FAD2B allele responsible for high oleic acid traits using allele specific marker. Result: Significant and positive correlation was found between dry weight and hundred pod weight (r=0.0.801) and harvest index (r=0.0.830). Molecular characterization along with morphological characterization identified highly diversified lines of groundnut. This study reports 78 foliar fungal disease resistant groundnut germplasm lines. Selected 11 groundnut germplasm lines represented resistance against LLS and rust diseases along with FAD2B allele for oleic acid trait.

Background: Soybean is a key crop that grants an imperative supply of oils and proteins to humans and animals; however, its productivity spectacularly diminished owing to the occurrence of drought stress. Methods: The present investigation was executed during Kharif 2018-2019 to recognize drought tolerant genotypes on the basis of an array of morpho-physiological traits. Morpho-physiological analysis among 53 genotypes divulged the existence of drought tolerance capability in studied genotypes.Result: On the basis of current findings, it can be concluded that drought stress retards the growth and metabolic activity of soybean genotypes. These parameters showed considerable amount of variability under drought stress at different growth stages in soybean. Among 53 soybean genotypes, four genotypes viz., JS97-52, AMS 2014-1, RVS-14 and NRC-147 was found to be drought tolerant.

Current projections suggest that the global population could reach nine billion by 2050. To meet the food demand of such a huge population, a 70% increase in global food production is projected by 2050. The conventional cereal crops might not be able to fulfill these requirements because the ultimate yield potential of most of these crops is currently at a plateau level. To replace the existing pressure on conventional crops, millets are the best alternatives in the near future considering the global food sustainability and nutritional reliability. By virtue of their exceptional nutritional profiles, they have a great potential to contribute to solve the malnourishment problems mainly in low-income food deficient developing countries. Also, the C4 photosynthetic pathway and its ability to combat the moisture stress make them a ultimate option for climate resilient agriculture. In spite of enormous perspective, attempt for the genetic advancement of millets is considerably lagged behind the conventional cereal crops. Research done so far in millets has decoded their exceptional nutritive value, broad adjustability, and phenotypic plasticity. Information on genetic mechanisms underlying important agronomic traits of millets including nutritional parameters is limited. To improve the crop very lesser efforts have been devoted by applying novel biotechnological and genomic tools. However, with the availability of draft genome sequences for some of the millets, there is wide scope to accelerate the progression of genetic improvement. This chapter is an attempt to gather the meager information available on the aspects of grain quality and nutraceutical development in millets by utilizing the potential of emerging genomics tools and techniques.

Background: The growth and productivity of soybean are adversely affected by an array of biotic factors. Viruses are one of them as they cause great loss to the yield of soybean in India. The present study was conducted with an objective to identify yellow mosaic virus (YMV) resistant genotypes among the selected set of 53 soybean genotypes. Methods: The field screening was performed to identify YMV resistant genotypes. The field data was compared with molecular data recorded on the basis of gene specific SSR molecular markers. Result: During field study, 11 genotypes were found to be highly resistant, 26 resistant, 6 moderately resistant, 4 moderately susceptible, 3 susceptible, while three genotypes namely: JS335, JS 97-52 and RVS 2001-4 were found to be highly susceptible. In molecular analysis three genotypes viz.,: JS 20-29, JS 20-69 and JS 20-98 were found to be resistant against YMV. Among the polymorphic SSR markers the highest genetic diversity (0.4785) was observed with Satt554 while lowest genetic diversity (0.037) was observed with Satt308. Similarly polymorphism information content (PIC) was highest (0.364) in Satt554 and lowest (0.0363) in Satt308 among all polymorphic markers used for screening against YMV. The resistant genotypes identified in this study may be used as donor of resistance gene against YMV to develop improved genotypes which would stand as barrier against spread of the disease to newer areas and thus it can boost production and productivity of soybean in the country.

Background: Chickpea (Cicer arietinum L.), a self-pollinating legume being cultivated globally as a rich source of vegetarian protein. It plays an important role in human feed and nutritional security, especially in agricultural-based communities. Chickpea has higher bioavailability of protein, good sources of polyphenols and flavonoids. Besides their nutritional value, chickpea seeds contain various phenolic compounds. Phenolic compounds are of particular interest due to their contribution to the seed colour, sensory characteristics and several biological properties. Flavonoids are one of the main groups of phenolic compounds found in grain legumes. Desi and Kabuli chickpeas are being used worldwide and there are few studies where both desi and kabuli chickpeas seed flour for above properties with respect to physiological traits has been reported. Methods: The present investigation has been formulated to compare popular chickpea genotypes of desi and kabuli types for biochemical parameters viz., protein content, amino acid, total flavonoid content, total phenolic contents and RSA as well as two physiological traits i.e., chlorophyll content and leaf area index. The experiment consisted of 44 genotypes () grown in Randomized Block Design with row to row distance of 30 cm, in two replications during Rabi 2018-19. Result: The average crude protein content in desi and kabuli chana varied from 18.2% (Dollar variety) to 26.7% (JG315) and total phenolic content (TPC) ranged 1.22 to 0.74 mg/g. Total Flavonoid content (TFC) varied from 0.39 (ICCV-2) to 0.61 mg/g (JAKI-9218) with mean value of 0.47. Radical scavenging activity (RSA) in chickpea genotypes ranged from 36.2 to 49.5% with mean value of 40.86%. Total amino acid significantly correlated with TPC and TFC and TPC significantly correlated with TFC at 5% significant level.

Fusarium wilt is one of the most destructive biotic stress reducing chickpea productivity worldwide. As a step towards understanding the basis of wilt resistance in chickpea, we investigated the morpho-physiological and biochemical traits of 29 desi and 15 kabuli chickpea genotypes and screened these genotypes for fusarium wilt disease using gene based molecular markers. The number of branches per plant were significant and positively correlated with number of pods per plant (r=0.635) and number of seed per plant (r=0.556) at 1% significance level. Biochemical parameters related to stresses were also analyzed for proline (1.19-3.92 µ mol/g), sugar (23.6-37.4 mg/g), malondialdehyde (MDA) (1.1 -3.67 nmol/g) and hydrogen peroxide (H2O2) (10.4-21.5 µ mol/g) in seeds of these genotypes grown under normal field conditions. Molecular screening was done by using15 gene-based markers. Polymorphic Information Content (PIC) value was in the range of 0.221 to 0.695, respectively. The genotypes JG-63 and Vijay identified during the investigation could be included in the hybridization programs during development of high yielding and wilt resistant varieties. The molecular markers TA194, TA-59, TA-96, TR-19, TR-29 and TR-31 can be used as marker assisted breeding tools for screening, validation and development of fusarium wilt resistant chickpea genotypes.

Nodal segments of sandalwood were cultured on MS medium amended with different plant growth regulators in varying concentrations to search out higher in vitro response leading to plantlet regeneration via somatic embryogenesis and/or organogenesis. Higher proportion of direct somatic embryogenesis, number(s) of somatic embryo per explant and plantlet regeneration via direct organogenesis were recorded on MS medium supplemented with a moderate concentration of TDZ (1.0 mgl-1) in combination with comparatively a lower concentration of NAA (0.5 mgl-1). A relative higher concentration of BAP (1.0-2.0 mgl-1) in combination with a lower concentration of NAA (0.5 mgl-1) promoted frequency of indirect somatic embryogenesis. Ratio of organ formation directly from surface of cultured explants was recovered from culture medium fortified with a higher concentration of BA at the concentration of 4.0 mgl-1 in combination with a lower concentration of NAA (0.5 mgl-1). Maximum plantlets regenerated via somatic embryogenesis (direct and/or indirect) on regeneration medium supplemented with 2.0 mgl-1TDZ in combination with 1.0 mg l-1GA3, while plantlets in higher frequencies via indirect organogenesis was attained with regeneration medium amended with comparatively lower concentration of TDZ (1.0 mg l-1) in combination with 0.5 mgl-1 GA3 and 0.5 mgl-1 NAA. The plantlets were transferred to pots and hardened in Environmental Growth Cabinet and Net House during preliminary weaning period and transferred to field successfully. Morphologically normal plants were recovered.

Jamun (Eugenia jambolana or Syzygium cuminii Skeels) is an important, large, evergreen beautiful tree of the myrtaceae family. Jamun is commonly known as java plum, black plum, jambul and Indian blackberry. It is widely consumed as fresh fruit which has considerable good nutritive value. It has high therapeutic and pharmacological properties because of constituent like tannins, alkaloids, steroids, flavonoids, terpenoids, fattyacids, phenols, minerals, carbohydrates and vitamins. The tests on animals have proved for hypoglycaemic, diuretics, analgesic, antiinflammatory, antiplaque, antimicrobial, antidiarrhoel, antioxidant, gastro-protective and astringency. However, the pharmacological trials using seeds of Syzygium cuminii have been reported in the previous studies but other parts of the tree also have good potential which need to be explored. Jamun fruit is good source of iron along with minerals, sugars and other phytochemicals. The fruits have sub-acid spicy flavour and commonly used as dessert. Apart from eating as fresh, it can also be used for the preparation of delicious beverages, jelly, jam, squash, wine, vinegar and pickles.

Madheshi society. For this study 350 currently married women aged 15-49 years were selected from Parsa district by using systematic random sampling. The in Parsa district of Nepal as it is prevailing in other developing countries. Madheshi women face domestic violence from various sources. Violence against women is practiced in Nepali society on the basis of discriminatory social, cultural, economic, religious and political traditions and beliefs. The violence and inhuman treatment such as sexual assault, rape and naked parading serve as a social mechanism to maintain women’s subordinate position in society. They are targeted as a way of humiliating entire Madheshi communities in Nepal. Social exclusion of Madheshi women, poor education, unemployment, low exposure, less autonomy in decision making, weak implementation of legal system etc. largely influence women’s status.Academic Voices Vol.5 2015: 67-72

The genetic assessment of 90 germplasm lines and six varieties of groundnut (Arachis hypogaea L.) were done with 13 morphological traits and 125 Simple Sequence Repeats markers. Out of 125 molecular markers, 26 were polymorphic and produced 105 alleles. The genetic diversity was found to be 52-83 per cent and Polymorphic Information Content (PIC) was 0.46-0.81 with a mean of 0.42 indicating higher magnitude of genetic diversity in the test genotypes. Analysis of molecular variance showed variation among and within individuals based on allelic variation. Principal Co-ordinate Analysis based on origin of the genotypes formed three major population groups and the genetic analysis determined by population structure divided all the germplasm lines in to 10 populations. Significant and positive correlation was observed between hundred kernel weight and hundred pod weight (r=0.769) and kernel yield (r=0.899); sound mature kernel and pod weight with kernel yield, weight of kernels and harvest index. Genotypes from distinct clusters may be selected in hybridization programme for groundnut improvement. The information on clustering of genotypes will be helpful in identification of novel and superior germplasm for hybridization and development of improved varieties.

A country’s socio-economic growth cannot take place if half of its population is down-trodden. In Nepal women of every section of society are excluded in one or other form. The identity of woman comes from her own family and decision-making autonomy also should start from the household. This article is concerned with the decision-making autonomy of the Madheshi women in Parsa district. The findings reveal that still these women are almost excluded from the structure of decision making autonomy within the households. It maybe argued that the status of Madheshi women is poorer due to low education and employment, low exposure of women and less decision making autonomy.DOI: http://dx.doi.org/10.3126/av.v4i0.12361Academic Voices Vol.4 2014: 68-72

Identification of a small core germplasm set representing the available genetic diversity is essential for its proper evaluation and subsequent utilization in rice improvement programmes. For constituting a small diverse mini-core panel of Indian rice germplasm, a representative set of 6912 accessions drawn based on their geographic origin from the whole rice germplasm collection available in the National Gene Bank was genotyped using 36 microsatellite markers. Automated fragment analysis of amplicons yielded a total of 435 alleles, with an average 12.4 and range of 3–29 alleles per locus. Polymorphism information content (PIC) ranged from 0.08 (RGNMS190) to 0.86 (RM552) with an average of 0.528. Based on genotyping data, a mini-core consisting of 98 genotypes was identified. Ninety-four per cent of the alleles present in the core set were present in the mini-core. The identified small but diverse panel will be useful for further intensive trait-specific evaluation and utilization in allele mining.

The aim of this study wa s to rule out the hypertensive individuals and to observe the effect of 30 minutes brisk walk for one month on ECG parameters. The ECG is often used as an inexpensive, early and fast screening tool to measure target organ damage in hypertensive individuals. Benefits of brisk walking also extend to people at risk for high blood pressure. An increase in aerobic physical activity sho uld be considered an imp ortant component of lifestyle modification for prevention and management of high blood pressure. All these cases of Hypertension were registered from Kayachikitsa O.P.D., IMS, BHU, for the duration of Jan 2009 to Jan 2011 and some healthy individuals were enrolled from th e Kashi Mumukshu, Bhavan, Assi and Varanasi, India . The selection was random irrespective of sex, occupation and socioeconomic deliberation. All the patients and healthy subjects belonged to age group of 35 to 65 years. One follow up has be en carried out during the research work i.e. initially and after one month . Duration of exercise has been prescribed 30 minutes walking. These subjects were demonstrated the scientifically designed exe rcise protocol and asked to continue these exercises fo r one month. ECG findings illustrated the decreased heart rate (p < 0.001 ), RR interval (p < 0.001 ), QRS interval (p < 0.001), PQ interval (p < 0.001) and ST segment (p < 0.001) in hypertensive exercise groups but this decrease was within normal range. W al king is safe, easy and useful physical activity for cardiac patients with reference to ECG parameters. All the ECG parameters show decreased value within the normal range.

Since half of the population of Nepal consists of women, it is natural that they should claim their rightful place in the society. Women’s political empowerment is a key component of democracy. Women’s relative status, however, varies from one ethnic group to another. Madheshi women are known to be more socially, politically, and economically oppressed than their Nepali sisters of other ethnic backgrounds.Ensuring participation at the grassroots level alone is not adequate for empowerment of women. Madheshi women have participated widely in political movements but after that theyare relegated again to the domestic arena and drowned women’s voices. So attaining positive role in national building, there should be identity, social inclusion, capacity enhancement which is the important prerequisites for a vibrant democracy and overall development of the country. This paper discussed on the situation of political awareness among Madheshi women of Parsa district. The primary data has used by the author in this research article.Academic Voices, Vol. 3, No. 1, 2013, Pages 68-75 DOI: http://dx.doi.org/10.3126/av.v3i1.9992

Normal 0 false false false EN-US X-NONE NE MicrosoftInternetExplorer4 In Madhes/Terai, the degree of social voice of the Terai Dalit is less pronounced in spite of the degree of exploitation and deprivation. In particular, landlessness in an agrarian society is more related to agrarian capitalism i.e. the most of the land is concentrated on the hands of few for their own economic interest, and the rest majority of the people are landless. The study aims to examine the situation of landless Madheshi Dalits and their actual problem faced by these landless Dalits. The study has selected Lalparsa VDC of Parsa District for field survey and both qualitative and quantitative techniques have used to get information from this group. The article based on the research, shows that most of the land is concentrated on the hands of few for their own economic interest, and the rest majority of the people are landless. Dalit are disadvantaged group in term of land ownership and also in economical and social dimensions. Most of the Madheshi Dalits are landless and household living in ailani (Government land with no legal tender) land. They have no access to land resources and have been suffering from landlessness, poverty and poor socio-economic condition in the country and situation is worst among Madheshi Dalits. DOI: http://dx.doi.org/10.3126/ijssm.v1i1.8689 Int. J. Soc. Sci. Manage. Vol.1(1) 2014 51-57

Soil salinity is a major constraint to rice production in large inland and coastal areas around the world. Modern high yielding rice varieties are particularly sensitive to high salt stress. There are salt tolerant landraces and traditional varieties of rice but with limited information on genomic regions (QTLs) and genes responsible for their tolerance. Here we describe a method for rapid identification of QTLs for reproductive stage salt tolerance in rice using bulked segregant analysis (BSA) of bi-parental recombinant inbred lines (RIL). The number of RILs required for the creation of two bulks with extreme phenotypes was optimized to be thirty each. The parents and bulks were genotyped using a 50K SNP chip to identify genomic regions showing homogeneity for contrasting alleles of polymorphic SNPs in the two bulks. The method was applied to ‘CSR11/MI48’ RILs segregating for reproductive stage salt tolerance. Genotyping of the parents and RIL bulks, made on the basis of salt sensitivity index for grain yield, revealed 6,068 polymorphic SNPs and 21 QTL regions showing homogeneity of contrasting alleles in the two bulks. The method was validated further with ‘CSR27/MI48’ RILs used earlier for mapping salt tolerance QTLs using low-density SSR markers. BSA with 50K SNP chip revealed 5,021 polymorphic loci and 34 QTL regions. This not only confirmed the location of previously mapped QTLs but also identified several new QTLs, and provided a rapid way to scan the whole genome for mapping QTLs for complex agronomic traits in rice.

Endosperm accounts for a large proportion of human nutrition and is also a major determinant of seed viability and size, not only in cereals, but also in species with ephemeral endosperms, such as soybean and oilseed rape. The extent of endosperm proliferation early in seed development is a crucial component in setting seed size; therefore, a biotechnological approach for the modification of this trait requires promoters active in early endosperm. To find such promoters, we constructed an array based on cDNAs extracted from developing Arabidopsis seeds enriched for proliferating endosperm. Hybridization with RNA extracted from vegetative and reproductive tissues, including endosperm, and subsequent data filtering yielded sets of endosperm-expressed and endosperm-preferred genes, including many hundreds not previously identified in array experiments designed to detect genes expressed in Arabidopsis seeds. Of eight promoters selected for validation, seven were active in early endosperm, three with no detected activity elsewhere in the plant. Therefore, this strategy has yielded proliferative phase endosperm promoters which should be useful in altering seed size.

Control of seed size involves complex interactions among the zygotic embryo and endosperm, the maternally derived seed coat, and the parent plant. Here we describe a mutant in Arabidopsis, megaintegumenta (mnt), in which seed size and weight are dramatically increased. One factor in this is extra cell division in the integuments surrounding mnt mutant ovules,leading to the formation of enlarged seed coats. Unusually for integument mutants, mnt does not impair female fertility. The mntlesion also has pleiotropic effects on vegetative and floral development,causing extra cell division and expansion in many organs. mnt was identified as a mutant allele of AUXIN RESPONSE FACTOR 2(ARF2), a member of a family of transcription factors that mediate gene expression in response to auxin. The mutant phenotype and gene expression studies described here provide evidence that MNT/ARF2 is a repressor of cell division and organ growth. The mutant phenotype also illustrates the importance of growth of the ovule before fertilization in determining final size of the seed.

Background Crossing plants of the same species but different ploidies can have dramatic effects on seed growth, but little is known about the alterations to transcriptional programmes responsible for this. Parental genomic imbalance particularly affects proliferation of the endosperm, with an increased ratio of paternally to maternally contributed genomes ('paternal excess') associated with overproliferation, while maternal excess inhibits endosperm growth. One interpretation is that interploidy crosses disrupt the balance in the seed of active copies of parentally imprinted genes. This is supported by the observation that mutations in imprinted FIS-class genes of Arabidopsis thaliana share many features of the paternal excess phenotype. Here we investigated gene expression underlying parent-of-origin effects in Arabidopsis through transcriptional profiling of siliques generated by interploidy crosses and FIS-class mutants. Results We found that fertilized fis1 mutant seeds have similar profiles to seeds with paternal excess, showing that the shared phenotypes are underpinned by similar patterns of gene expression. We identified genes strongly associated with enhanced or inhibited seed growth; this provided many candidates for further investigation including MADS-box transcription factors, cell cycle genes, and genes involved in hormone pathways. Conclusions The work presented here is a step towards understanding the effects on seed development of the related phenomena of parental genome balance and imprinting.