000			01665nam a2200181Ia 4500
020			_a9788177540239
040			_cCUS
082			_a635.0423 _bKUM/T
100			_aKumar, J.C. _92732
245		0	_aTechniques of developing hybrid in vegetable crops/ _cJ.C. Kumar and M.S. Dhaliwal.
260			_aJodhpur: _bAgrobios, _c2007.
300			_av, 69 p. : _bill. ; _c21 cm.
505			_aThe term heterosis was first coined by shull, signifies an increased or decreased vigour of F1 hybrids over the midparent or better parental vslues. Hybrid cultivar is used to designate F1 populations can be obtained by crossing clones, openpollinated varieties, inbred lines, pure lines or other populations that are genetically diverse exploiting different pollination mechanisms such as male-sterility, self-incompatibility, dioecy, monoecy, etc. The secret of success of F1 hybrids lines in the fact that all plants are exceptionally uniform in growth and development, resistant to insect-pest and disease, better adaptability to changing and adverse ecological conditions (homeostatic) andabove all give high early as well as total yields. Resistance to insects, pests and diseases when dominant over insects, pests and diseases when dominant over susceptibility can be directly availed in F1 hybrids thus eliminating the tedium of selecting resistant segregates in successive generations. In addition to superior performance by hybrids due to heterosis, intermediate state of gene expression in heterogygotes may be of potential value.
650			_aVegetable Crops. _925038
650			_aTechniques of developing hybrids. _925039
700			_aDhaliwal, M.S.
942			_cWB16
999			_c150693 _d150693