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Maize (Zea mays) is the third major cereal crop in the Indian subcontinent, but the crop yields per hectare of Indian maize cultivars are less than half of the global average due to the impurity of seed lots supplied to farmers. In this study, we discovered high-quality Single Nucleotide Polymorphic markers (SNPs) in two widely cultivated maize hybrids and their parental inbreds. Paired-end double digest restriction site-associated DNA sequencing was used to discover SNPs and a total of 30,764,454 reads with a read length of 151 bp per sample were generated. Genotyping of SNPs for maize hybrids 'MAH 14-5' and 'Hema' revealed a total of 47,812 and 15,815 Genetic Purity Analysis markers, respectively, of which 44,388 and 12,391 were unique with 3,424 being common to both hybrids. Identified SNPs were used to develop primers for Kompetitive Allele-Specific PCR genotyping assays to determine the genetic purity of 10 seed lots and the results were found to correlate with Grow-out-Tests. Thus, the SNPs discovered in this study proved reliable to test the genetic purity of commercial seed lots. Advances in plant molecular breeding tools especially ddRADseq for SNP discovery offer new opportunities to genotype existing cultivars and accelerate the production of genetically pure seeds.

Soilless agriculture is one of the advanced techniques to cultivate plants without soil, with minimal water and nutrients, and helps in vertical growth of agricultural technology. It is an eco-friendly approach widely used for commercial cultivation of quality vegetables. An experiment was conducted at University of Agricultural Sciences, GKVK, Bengaluru, Karnataka during 2017–19 to evaluate the potentiality and suitability of the hydroponics (M2) and aeroponics (M3) methods over conventional method (M1) for hybrid seed production of tomato (Solanum lycopersicum L.). The experiment had 12 treatments comprising 3 methods of production, 2 parental lines (TAG 1F and TAG 2F) and 2 seed treatments (S1: Control and S2: thiram @2g/kg + chlorpyrifos @3g/kg). Hoagland nutrient solution with pH 5.5–6.5 was used for soilless systems. The results revealed that, among the parental lines, TAG 1F performed better under all the methods of hybrid seed production. Seed treatment increased the per cent survival rate to the tune of 3.26%. Aeroponics and hydroponics performed better than conventional method. Aeroponics showed significantly higher plant height (140.94 cm), fruit weight (124.54 g), total biomass (106.44 g) and test weight (0.39 g) while, hydroponics showed significantly higher number of fruit/plant (45.84) and SVI (2821). It is inferred that soilless agriculture could be a promising tool for quality and year-round healthy hybrid tomato seed production under protected cultivation.

Background: The agricultural sector is highly dependent on the availability and quality of seeds for a productive harvest. The global demand for food and water is expected to increase due to population outgrowth, urbanization and climate change. Soilless farming may change the face of agriculture by providing a more sustainable and productive alternative to traditional cultivation and is being largely exploited for vegetable cultivation. Methods: The experiment consisted of 12 treatments. Two parental lines (P1: TAG 1 and P2: TAG 2) were subjected to seed treatment (S1: Untreated and S2: Thiram @ 2g kg-1 and chlorpyrifos @ 3g kg-1) and twenty-eight days old seedlings were transplanted to soil (M1: Conventional) and soilless systems (M2: Hydroponics and M3: Aeroponics). Hybrid seeds were produced in all the system were analysed for the quality and economics of seed production in soilless system was worked out. Result: The results revealed that there was a significant increase in test weight (0.39 g), average seed length (0.52 cm) in the soilless system due to the continuous availability of nutrients at controlled condition. Although the cost incurred was comparatively higher in the soilless method, the gross return was 94.68 per cent higher under aeroponics and 79.22 per cent higher under hydroponics compared to the conventional method. The benefit to cost ratio was found higher in aeroponics (2.08) followed by hydroponics (1.97) and lower under the conventional method (1.87). It is inferred that soilless agriculture could be a promising tool for quality and healthy hybrid tomato seed production throughout the year within protected cultivation.

Identification of donor parents and markers for traits conferring drought tolerance eventually hastens the breeding for drought tolerance in rice. The extent of variation for water stress indicators, physio-morphological and plant production traits were assessed by evaluating 36 rice genotypes under water stress condition. Significant variation was observed for these traits and thirteen drought tolerant and susceptible genotypes were selected and grouped as tolerant and susceptible bulks based on physio-morphological and biochemical characterization. Genomic DNA was isolated from these rice accessions and pooled, respectively into drought tolerant and susceptible bulks. Bulked line analysis was carried to identify microsatellite markers linked to drought tolerance in rice. Out of 200 SSR primers screened RM 1092; RM 129 and RM157B were polymorphic between the bulks and also co-segregated among the individual genotypes constituting the respective bulks. The genomic regions flanked by these markers have been identified to be associated with various drought tolerance traits in rice and can be useful for marker assisted selection for drought resistance improvement in rice. The genotypes identified as drought tolerant can be used us donars in drought improvement breeding programmes. Key words Rice, drought resistance, microsatellite markers, bulk line analysis

Seed deterioration during storage is associated with various metabolic and chemical alterations that vary among genotypes in soybean. In the present study, five genotypes with good storability viz., kalitur, MACS 1416, EC 18761, CO1 and DSB21 and five genotypes with poor storability viz., JS 71-05, DS 228, MAUS 61, NRC 93 and DSB 24 were selected and evaluated for biochemical changes to identify the best donors for storability. Among the genotypes, all the poor storer genotypes showed faster accumulation of free amino acids, free fatty acids and malondialdehyde content as a result of oxidative stress. Poor storer genotypes also showed the increased lipoxygenase I and II enzymes activity. All the good storer genotypes showed higher anti-oxidative enzymes activity causing slower lipid peroxidation. Among the good storers, kalitur showed favourable biochemical features for storability while MAUS-61 was identified as poor storer exhibiting less favourable biochemical features.

Quality seeds are inevitable to meet the challenges of ever increasing population and food security. Being the carrier of technology, seed over the period of time evolved as the trade commodity. India being the 5th largest player in global seed market and a wide range of crop seed being produced under varied agro-climatic condition, there is a scope for up-scaling revenues through seed export. Seed quality assurance in India comes under the jurisdiction of the Seeds Act 1966, wherein quality seed must satisfy the requirements of Indian Minimum Seed Certification Standards (IMSCS), but under global scenario seed quality assurance system for seed export comes under the scope of Organization for Economic Cooperation and Development (OECD) standards and International Seed Testing Association (ISTA) methodology of seed testing. The present paper reviews the major discrepancies in standard operating procedures/methodologies of seed quality assurance system under IMSCS vis-Ã -vis ISTA international rules for seed testing and OECD seed scheme. Critical analysis of discrepancies suggests there is need to harmonize existing quality assurance system in India with OECD and ISTA standards for carving a special niche for Indian seed in international seed domain and to facilitate international seed trade. An attempt has also been made in the present paper to elucidate the issues prevalent in seed production with special emphasis on breeder seed production, regular erratic spans due to disruptive climate and strategies for energizing the quality seed production in field crops through production in off-season / alternate areas.

Increased use of genetic resources is necessary to sustain crop improvement. Large numbers of germplasm entries and possible existence of duplicate/redundant accessions are impediments to effective management, evaluation, and utilization. A core collection is a limited set of accessions chosen to represent the maximum genetic spectrum with minimum redundancy of the existing germplasm collection. Six hundred forty-four indigenous and exotic germplasm accessions of Dolichos bean [Lablab purpureus (L.) Sweet] and four check entries were characterized for 21 qualitative traits and evaluated for 20 quantitative traits at the University of Agricultural Sciences, Bangalore, India, during the 2012 rainy season. A core set of size 10% (n = 64 accessions) was developed using software that applies advanced M-strategy with a heuristic search. The core set was examined for its representativeness of the base collection for both qualitative and quantitative traits using univariate and multivariate statistics. The core s...

During the course of our investigation on the selective isolation and in vitro pathogenicity tests of the nematode egg parasite and endoparasitic Catenaria anguillulae and the nematode-trapping fungus Dactylaria brochopaga against Anguina tritici , and Meloidogyne graminicola, the two biocontrol agents were also examined for their capabilities to colonize wheat seed gall and also to reduce the M. graminicola , and A. tritici in wheat ( Triticum aestivum L.). Using seed galls as bait was found effective for isolating the soilborne natural colonizers of seed galls of wheat caused by A. tritici . Seed galls were found severely infested with cellulose decomposers as well as nematode trapping fungi i.e., Fusarium spp ., Verticillium spp., Aspergillus spp., Penicillium spp. Arthrobotrys oligospora , Arthrobotrys superba , Arthrobotrys dactyloides , Arthrobotrys musiformis , D. brochopaga , Monacrosporium eudermatum, Stylopaga hadra, Paecilomyces spp., and C. anguillulae . Co-inoculation of D. brochopaga DBS-105, and C. anguillulae CAS101 significantly reduced the root knot and seed gall in wheat and increased the plant growth parameters including length, and dry weight of root and shoot as well as yield attributing characters like spike length; number of seed per spike, test weight etc. under greenhouse conditions as compared to pathogen challenged plants without any bioagents/chemical nematicide. These bioagents have the potential to enhance production of quality seeds of wheat being free from hazardous pesticides and thus, can further be developed into marketable formulations in order to promote eco-friendly and sustainable means of crop production.

Summary Identification of rice genotypes is of prime importance to ensure quality seed, which is required for achieving global food demand. Three rice hybrids and their parental lines were identified on the basis of seed colour, seed size and 1000 seed weight, response to different chemicals (Phenol, Modified phenol with Copper sulphate or Ferrous sulphate, NaOH, GA3 and 2,4-D) and electrophoresis of soluble seed proteins (SDS-PAGE). All the genotypes were identified by using key based on seed colour, 1000 seed weight and seed size except for the female lines and their maintainers. No individual chemical test was able to distinguish all the genotypes. However, the combinations of different rapid chemical tests were useful in identification of individual genotypes. While all the cultivars were identified successfully by using electrophoresis of seed protein (SDS-PAGE) and hence it could be used as a powerful tool to identify every genotype in a short period of time.

The present study was based on primary data collected for 100 farmers from Gulbarga district of Karnataka during the agricultural year 2013-14. Tabular and discriminant function analysis was used in the present study. The analysis of data shows that the total cost of cultivation in pigeonpea seed production was around 23 per cent higher than grain production. The variable cost was comparatively higher in seed production (26936 per ha) over grain production (20698 per ha). The gross return was about 32 per cent higher in seed production than grain production and net return from seed production of pigeonpea was 44 per cent higher than grain production. The discriminant analysis indicated that gross return with 55.88 per cent followed by seed (18.52 per cent), human labour (8.35 per cent), manures and fertilizers (7.01per cent), bullock and machine labour (5.99 per cent), plant protection chemicals (4.26 per cent) contributed to discriminate between the seed and grain production of pigeonpea. The net return from pigeonpea seed production was encouraging, therefore the area under seed production may be increased for higher profitability and timely supply of quality seed to the farmers.