SBIR-STTR Award

The lack of efficient tools to identify genotypes of superior water-use efficiency (WUE) has led to little practical success in improving crops with regard to this very important trait. However, stable carbon isotope (?l3C) analysis is presently emerging as a potentially highly efficient means of evaluating plants for WUE, although the technology has not yet been applied to crop development. In a preliminary study it was found that a wild tomato species (L. pennellii) was of much greater WUE than was the domestic tomato (L. esculentum) and that the interspecific F1 hybrid inherited the WUE of the wild parent. WUE was further found to be strongly positively correlated with ?l3C. In a second small study it was found that the predictions of ?13C based on restriction fragment length polymorphisms (RFLPs) very accurately reflected observed ?13C values, and that as few as three RFLP loci contributed over 70% of the variance for ?13C. In this Phase I project, the correlation between WUE, ?13C, and RFLPs in tomato will be confirmed in a bigger, greatly variable population (F2). If this correlation can be demonstrated, it offers the advantages of (1) evaluation and comparison of plants grown in any environment, (2) simultaneous selection for multiple traits-one of them being WUE via RFLP selection indices, and (3) the opportunity to identify the actual genes targeted by the RFLPs, cloning of these genes, and their use in crop improvement through transformation of higher plants. The technical approach is suitable for all C3 plants provided that sufficient genetic variability and RFLPs exist.Anticipated Results/Potential Commercial Applications as described by the awardee: It is anticipated that (1) ?13C can be used to screen plants for WUE, (2) models based on RFLPs can predict ?13C and, therefore, indirectly WUE, and (3) eventually the WUE genes can be identified. The technologies can be applied in (a) screening for WUE in wild and domestic germplasms, (b) selection and breeding, and (c) cloning of WUE genes and transformation of plants.Topic 6: Botanical Research Techniques and Instrumentation

The lack of efficient tools to identify genotypes of superior water-use efficiency (WUE) has led to little practical success in improving crops with regard to this very important trait. However, stable carbon isotope (?l3C) analysis is presently emerging as a potentially highly efficient means of evaluating plants for WUE, although the technology has not yet been applied to crop development. In a preliminary study it was found that a wild tomato species (L. pennellii) was of much greater WUE than was the domestic tomato (L. esculentum) and that the interspecific F1 hybrid inherited the WUE of the wild parent. WUE was further found to be strongly positively correlated with ?l3C. In a second small study it was found that the predictions of ?13C based on restriction fragment length polymorphisms (RFLPs) very accurately reflected observed ?13C values, and that as few as three RFLP loci contributed over 70% of the variance for ?13C. In this Phase I project, the correlation between WUE, ?13C, and RFLPs in tomato will be confirmed in a bigger, greatly variable population (F2). If this correlation can be demonstrated, it offers the advantages of (1) evaluation and comparison of plants grown in any environment, (2) simultaneous selection for multiple traits-one of them being WUE via RFLP selection indices, and (3) the opportunity to identify the actual genes targeted by the RFLPs, cloning of these genes, and their use in crop improvement through transformation of higher plants. The technical approach is suitable for all C3 plants provided that sufficient genetic variability and RFLPs exist.Anticipated Results/Potential Commercial Applications as described by the awardee: It is anticipated that (1) ?13C can be used to screen plants for WUE, (2) models based on RFLPs can predict ?13C and, therefore, indirectly WUE, and (3) eventually the WUE genes can be identified. The technologies can be applied in (a) screening for WUE in wild and domestic germplasms, (b) selection and breeding, and (c) cloning of WUE genes and transformation of plants.Topic 6: Botanical Research Techniques and Instrumentation