Some studies have demonstrated “hidden diversity.” This term means that, despite the complex genetics and diverse physiological mechanisms underlying the abiotic stress tolerances, introgression of genes from a diverse source of donors into elite genetic backgrounds through breeding and efficient selection (careful screening under severe stress) is a powerful way to exploit this hidden diversity to improve abiotic stress tolerances of rice (Li et al., 2005; Ali et al., 2006). Genetic control of grain chalkiness demonstrated that transgressive inheritance often occurs in many combinations (Tan et al., 2000; Zhou et al., 2009). In this study, we found 39 inbred lines whose chalkiness grains are null. These studies revealed that two parents both have hidden diversity.