Genetic purity analysis of hybrid broccoli (Brassica oleracea var. italica) seeds using RAPD PCR

Abstract

Determination of genetic purity of F₁-hybrid seeds is aquality control requirement in the production of hybrid Brassica vegetableseeds. Hybrid varieties of these vegetable crops have arisen from a limitedgermplasm base, making discrimination of parental and hybrid lines verylaborious and troublesome. The use of RAPD PCR for evaluating seed purity in acommercial F₁-hybrid broccoli a single cultivar bywithholding water. In Expt 2, plants of EP and MK were grown together in thesame container and received water daily with gradation in intensity of waterdeficit achieved by varying the daily water ration per container.

All cultivars in each experiment exhibited commonly reported responses towater deficit, characterised by diminished evaporative surface area andincreased root : shoot ratio. The response of MK was primarily morphologicaland MK plants had smaller plant size, higher root : shoot ratio, and a lowergrowth rate compared with temperate cultivars. By contrast, response oftemperate cultivars was primarily physiological; stomatal conductance oftemperate cultivars was lower and these cultivars had a greater tendency forleaf lamina osmotic a