TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Vector: The vector is selected from a binary vector, an expression vector, a viral vector, a phage, a phagemid, a cosmid, or a plasmid. The expression vector comprises a constitutive, developmentally regulated or inducible promoter that can drive expression of the nucleic acid in plants under specific conditions. Preferred Cell: The cell is a plant cell. Preferred Plant: The plant is a monocotyledonous plant selected from maize, sorghum, switchgrass, Miscanthus, sugarcane, wheat, rice, rye, turfgrass, millet, and any grass species. The plant is a dicotyledonous plant selected from tobacco, tomato, potato, soybean, canola, sunflower, alfalfa, cotton or poplar, or any tree species. The plant expresses a gene encoding any other cell wall modifying enzyme created either by a gene stacking technology or by traditional plant breeding method. A polypeptide encoded by a nucleic acid is used to modify covalent linkages or ionic or hydrogen bonding interactions in plant cells, where the enzyme activity of the polypeptide is active in vivo or can be made active ex vivo by post-harvesting processing, where the covalent linkages or ionic or hydrogen bonding interactions are selected from hemicellulose-cellulose-lignin, hemicellulose-cellulose-pectin, hemicellulose-diferululate-hemicellulose, hemicellulose-ferulate-lignin, mixed beta-D-glucan-cellulose, mixed-beta-D-glucan-hemicellulose, pectin-ferulate-lignin, and their combinations. Post-harvest processing to stimulate ex vivo polypeptide activity is selected from fensilage, thermochemical bioprocessing, and their combinations. Post-harvest processing to stimulate ex vivo polypeptide activity occurs in the digestive tract of a mammal. Relative proportions of cellulose, hemicellulose, lignin, mixed-beta-D-glucan, ferulic acid esters and pectin are altered so as to improve biomass characteristics for improved total fermentable production. Expression of the stay-green gene is reduced. Expression of the stay-green gene is altered by a mutation, where the stay-green gene is inactivated by the mutation. The lignocellulolytic enzyme polypeptide is selected from a cellulase polypeptide, a hemicellulase polypeptide, a ligninase polypeptide, and their combinations. The lignocelluloytic enzyme polypeptide hydrolyzes at least one plant cell wall component, where the lignocellulolytic enzyme polypeptide hydrolyzes at least one plant cell wall component selected from xylans, xylan side chains, glucuronoarabinoxylans, xyloglucans, mixed-linkage glucans, pectins, pectates, rhamnogalacturonans, rhamnogalacturonan side chains, lignin, cellulose, mannans, galactans, arabinans, oligosaccharides derived from cell wall polysaccharides, and their combinations. The lignocellulolytic enzyme polypeptide hydrolyzes at least one interaction in plant cell wall, where the lignocellulolytic enzyme polypeptide hydrolyzes an interaction selected from covalent linkages, ionic bond interactions, hydrogen bond interactions, and their combinations. The transgenic plant is a progeny of a cross between a first plant whose genome comprises a recombinant polynucleotide encoding at least one lignocellulolytic enzyme polypeptide linked to a promoter sequence and a second plant whose genome comprises a mutant stay-green gene. The transgenic plant is obtained from a line of transgenic plants established by a cross between a first plant whose genome comprises a recombinant polynucleotide encoding at least one lignocellulolytic enzyme polypeptide linked to a promoter sequence and a second plant whose genome comprises a mutant stay-green gene. The recombinant polynucleotide is optimized for expression in the plant. Preferred Method: In the method for cost-effective processing of lignocellulosic biomass, pre-treating comprises incubating the plant part with heat alone or heat applied under either acidic or alkaline conditions. The alkaline conditions comprise applying ammonia. Pretreating is performed at less than 200 degrees C, preferably less than 115 degrees C. Treating comprises externally applying an amount of a lignocellulolytic enzyme cocktail capable of hydrolyzing cellulose and hemicellulose to fermentable sugars to the mixture. The amount of externally applied lignocellulolytic enzyme cocktail required to achieve a given level of hydrolysis is less than the amount of externally applied lignocellulolytic enzyme cocktail required to achieve the same level of hydrolysis of comparable lignocellulosic biomass from a plant part that is not obtained from a transgenic plant, where lignocellulosic biomass from a plant part from a pretreated transgenic plant yields a greater level of hydrolysis than a plant part from a non-transgenic plant at the same pretreatment temperature when both plants are treated with the same level of lignocellulolytic enzyme cocktail. In the method of producing fermentable sugars, the cellulose and hemicellulose in the fiber is hydrolyzed by enzyme or enzymes produced by the plant. The starch is hydrolyzed by amylase enzymes added exogenously or produced by the plant. Cellulose and hemicellulose in the fiber is hydrolyzed by cellulase and hemicellulase enzymes produced in the plant and where the starch is hydrolyzed by exogenously added or plant-produced amylase enzymes. In the method of producing higher levels of fermentable sugars compared to non-transgenic corn grain, hydrolysis of the cellulose and hemicellulose in the grain produces additional fermentable sugars compared to non-transgenic grain. Reducing the recalcitrance of plant biomass to pretreatment and hydrolysis comprises delaying or reducing crystallinity of the cellulose by providing a variety of a grain, where which leaves and stems of the stay-green grain crop variety remain green and have a higher water content than other crop plants when the grain is dried down. Grain and stover are harvested simultaneously, and where grain and stover are separated for processing into fermentable sugars. A method comprises obtaining a corn kernel; and separating the kernel into a high starch portion and a high fiber-containing bran portion, where the corn kernel is obtained from at least one transgenic plant, the genome of which comprises a recombinant polynucleotide encoding at least one lignocellulolytic enzyme polypeptide operably linked to a promoter sequence. The method further comprises pretreating the high starch portion under conditions to promote accessibility of celluloses within the lignocellulosic biomass; and treating the pretreated high starch portion under conditions that promote hydrolysis of cellulose to fermentable sugars. The high starch portion comprises endosperm. The high fiber portion comprises a component selected from pericarp, germ, tip cap, and their combinations. The transgenic plant further comprises at least one stay green gene whose expression in the plant is altered. SPECIFIC SEQUENCES - The nucleic acid encodes an enzyme which comprises any of the 70 defined sequences comprising 252-1217 amino acids (SEQ ID NO: 1-70), given in the specification.    EXAMPLE - No suitable example given.