Germination and seedling emergence are the critical stages in the plant life cycle. Insufficient seedling emergence and inappropriate stand establishment are the main constraints in the production of crops which receiving less rainfall. Farmers do not have sufficient resources to meet the requirement of seedbed preparation for sowing and they are at more risk as compared to progressive farmers. On the other hand good establishment increases competitiveness against weeds, increases tolerance to drought period, increase yield and avoids the time consuming need for re-sowing that is costly too. It is well accepted fact that priming improves germination, reduces seedling emergence time and improves stand establishment. A method to improve the rate and uniformity of germination is the priming or physiological advancement of the seed lot. The general purpose of seed priming is to partially hydrate the seed to a point where germination processes are begun, but they would exhibit rapid germination when re-imbibed under normal or stress conditions. A lot of work has been done on seed priming and results of these studies indicate well the importance of priming to get a good crop stand in many crops of tropical region such as rice, maize, sorghum and pigeon pea.

Lignocellulosic biomass has the potential to serve as feedstock and direct replacement for petrochemicals in the fuel, chemical, pharmaceutical and material industries. Energy cane has been identified by the U.S. Department of Energy (DOE) as prime lignocellulosic feedstock as it produces record biomass yields and is able to grow on low-value land with reduced inputs. Molecular improvement of energy cane is an essential step toward the development of a high-value crop and may contribute to improved biomass conversion to value added products. Such improvements require a development of an efficient regeneration and transformation system for the vegetatively propagated energy cane varieties. In this report, an efficient biolistic gene delivery protocol for energy canes (genotype L 79-1002 and Ho 00-961) has been established with immature leaf rolls as explants. Embryonic calli, developed approximately 6 weeks after culture initiation and was used as target for biolistic transfer of a minimum expression cassette of P-ubi::nptII::35S polyA derived from plasmid pJFNPTII. Putative transgenic clones of callus were obtained after selection on callus induction medium supplemented with 30 mg l(-1) geneticin. Regeneration was carried out on NB medium, which is modified from MS supplemented with 1.86 mg l(-1) naphthaleneacetic acid (NAA) and 0.1mg l(-1), 6- benzylaminopurine (BAP) and 20mg l(-1) paromomycin. Shoots growing on selection media were transferred to hormone free medium with 20 mg l(-1) paromomycin. Putative transgenic lines were first analyzed by PCR. Transgene integration was confirmed by Southern blot analysis. ELISA (Enzyme-Linked Immunosorbent Assay) and Immunochromathography assays confirmed transgene expression.

Curcuma longa L. is a sterile, triploid, vegetatively-propagated crop cultivated mainly in Southeast Asia. When dried rhizomes are ground, the resulting yellow powder is used by the food industry as a natural food dye. Moreover, many pharmacological compounds have broadened the commercial application of the crop. However, conventional breeding is difficult and hence, improvement has been limited to germplasm selection. To better utilize the germplasm collections and facilitate genotype selection, a total of 17 polymorphic microsatellite loci were developed using a CT/GT/CTT enriched genomic library. All microsatellites resulted in amplified PCR products, showing a banding pattern of 2-11 polymorphic bands per locus, enabling genotype discrimination. These results can be used in further studies aimed at characterizing C. longa genetic resource collections and also to improve breeding strategies.

Two field experiments were conducted to ascertain the potential of micropropagation technique for faster production of seed cane by using tissue culture plants raised through apical meristem culture in first generation (TC 0) followed by clonal propagation through cane setts in next generation (TC1). About 18, 520 plants, produced from a single shoot through micropropagation, were required at row to row and plant to plant spacing of 90 and 60 cm, respectively as compared to 88 quintal of cane seed in conventional methods for planting in an area of one hectare. Multiplication ratio was 100-150 times using tissue culture plants as compared to 11-12 using conventional cane setts, leading to drastic reduction in seed cane requirement. The TC 1 exhibited superiority over vegetatively propagated conventional crop for millable canes and stalk yield by 17 and 10.4 per cent, respectively. Though the single cane weight and cane diameter (non-significantly) were slightly lesser in TC1 as compared to conventional crop, this did not distress its potential as seed crop. The incidence of Ratoon Stunting Disease (RSD) and Leaf Scald Disease (LSD) was very low in TC 1 crop as compared to conventional crop. The findings established the potential of tissue culture technique for the production of quality seed free of pests and pathogens in the existing varieties and rapid multiplication of newly released varieties for quick adoption by the growers.

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