BP Singh

96 R.V. Singh(c) Resistance approach: Incorporation of chemical changes inplant composition as terpenoids, phenols and those which help tomake cotton plant less vulnerable to pests aJ;ld even diseases isnecessary. The development of MAR and 'MDR lines through thesetechniques is a possible solution to cut costs of plant protection,reduce risks to the grower and environmental pollution. Lines forbollworm resistance with dense glands flower buds and redpigment trait in combir).ation with high terpenoid level specificallyfor Heliothis resistance are being established as a possible solutionto control bollworm menace. Diploid wild genome introgressioninto· the cultivated background is known to contribute forresistance to bacterial blight, rust, fusarium wilt, drought andinsect pests.Germplasm represents the most important biological tool tobring about a real technological breakthrough in rainfed cotton.Atleast 15000 germplasm stocks are known to be available in majorgenetic resources centres of the world ih cotton of which nearly6000 lines have been assembled in India. Recently two more newspecies G. Jryxellii and C. binatum have been identified. This hasopened up the scope for creating a large number of new nuclearcytoplasmic combinations of the wild species genomes.A to G oncultivated A and AD genomic backgrounds. Our gene pool alsoneeds enlargement through the acquisition of exotic types fromUSA, USSR, China and Australia besides undertaking newexpeditions in the old and new worlds. Therefore, emphasisshould be given for the introduction of exotic germplasm resourcesin co~ton as discussed' above for the various traits. Germplasm isalso required in jute and other allied fibres for future needs.Under utilized and under exploited cropsThere is an urgent need to introduce new exotic germplasmin different under utilized crops particularly in Amaranthus, Jojoba,Ipil-Ipil, Euphorbia, chenopods, A trip lex and other new potentialcrops. .Plant resources that require introduction: A new oil yielding cropworth trying for the arid lands is Cuphea. The seeds of Cupheaspecies belonging to family Lythraceae, contain 16-42% oil and thatthese oils have high levels of lauric acid and their medium chainfatty acids. Efforts have been made in USA to collect wild 'CupJ1eagermplasm from Mexico and Brazil which are recognised as