To identify cold-, drought-, high-salinity-, and/or abscisic acid (ABA)-inducible genes in rice (Oryza sativa), we prepared a rice cDNA microarray including about 1,700 independent cDNAs derived from cDNA libraries prepared from drought-, cold-, and high-salinity-treated rice plants. We confirmed stress-inducible expression of the candidate genes selected by microarray analysis using RNA gel-blot analysis and finally identified a total of 73 genes as stress inducible including 58 novel unreported genes in rice. Among them, 36, 62, 57, and 43 genes were induced by cold, drought, high salinity, and ABA, respectively. We observed a strong association in the expression of stress-responsive genes and found 15 genes that responded to all four treatments. Venn diagram analysis revealed greater cross talk between signaling pathways for drought, ABA, and high-salinity stresses than between signaling pathways for cold and ABA stresses or cold and high-salinity stresses in rice. The rice genome database search enabled us not only to identify possible known cis-acting elements in the promoter regions of several stress-inducible genes but also to expect the existence of novel cis-acting elements involved in stress-responsive gene expression in rice stress-inducible promoters. Comparative analysis of Arabidopsis and rice showed that among the 73 stress-inducible rice genes, 51 already have been reported in Arabidopsis with similar function or gene name. Transcriptome analysis revealed novel stress-inducible genes, suggesting some differences between Arabidopsis and rice in their response to stress.

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The molecular marker is a useful tool for assessing genetic variations and resolving cultivar identities. Information on genetic diversity and relationships among rice genotypes from Pakistan is currently very limited. The objective of this study was to evaluate the genetic polymorphisms and identities of 10 traditional, 28 improved and 2 Japanese cultivars of rice using the random amplified polymorphic DNA technique. Twenty-five decamer-primers could generate a total of 208 RAPD fragments, of which 186 or 89.4% were polymorphic. The number of amplification products produced by each primer varied from 4 to 16 with an average of 8.3 bands primer -1 . The size of amplified fragments were ranged from 200 to 4000 bp. Pair-wise Nei and Li's similarity had estimated the range of 0.50 to 0.96 between rice cultivars. Based on analysis performed on a similarity matrix using UPGMA, 40 cultivars were grouped into 3 main clusters corresponding to aromatic, non-aromatic and japonica group. There were a few of independent cultivars. The cluster analysis had placed most of the aromatic cultivars into a close relation showing a high level of genetic relatedness. However, the clusters formed by the *Corresponding author aromatic cultivars were distinct from those of nonaromatic and japonica types. Interestingly, a number of improved and traditional cultivars originating from diverse sources did not form well defined groups and were interspersed, indicating no association between the RAPD patterns and the geographic origin of the cultivars. The information generated from this study can be used to maximize selection of diverse parents and broaden the germplasm base in the future of rice breeding programs.Rice (Oryza sativa L.) is one of the most important crops that provide food for more than half of the world population. It is no longer a luxury food but has become the cereal that constitutes a major source of calories for the urban and the rural (Sasaki and Burr, 2000). Rice is cultivated in a wide range of ecological environments worldwide. Pakistan is one of the few countries which had an enormous wealth of aromatic rices and old landraces. Many have been lost during the last three decades after green revolution. A number of traditional varieties and improved cultivars have been released for cultivation in different regions of Pakistan since the early nineteen

Developing high yielding safflower cultivars with good adaptation to diverse environmental conditions can improve production in terms of seed yield and reduce the deficiency in edible oil. The genetic variability that exists among and within populations for desirable agronomic traits can be used to develop elite cultivars. A total of 94 safflower accessions from 26 different countries were used in this study to evaluate morphoagronomic performance, determine the pattern of similarity centers, and identify the best performing accessions by conducting 2 field experiments in Pakistan and Turkey using augmented design. Genetic diversity for important yield and yield traits was described including capitulum diameter (17.30 to 28.30 mm), branches per plant (5.10 to 17.30), capitula per plant (8.70 to 80.40), and seed yield per plant (4.86 to 51.02 g). These analyses showed a good level of variation in the current study. Using principal component analysis, it was observed that days to flower initiation, days to 50% flowering, days to flower completion, seed yield per plant, capitula per plant, branches per plant, seeds per capitulum, and capitulum diameter were the major contributors to the observed genetic variability in the evaluated safflower panel. Seed yield per plant reflected a significant and positive correlation with capitula per plant, branches per plant, and capitulum diameter, and these traits can be suggested as a selection criterion in safflower breeding programs. The hierarchical clustering was in agreement with the patterns of 7 similarity centers based on seed yield per plant, capitula per plant, capitulum diameter, and branches per plant. During this study, a few promising safflower accessions were selected for future breeding programs.

ABSTRACT. Cereal crops that have rigid non-cellulose components in the cell wall tissues of leaves and high starch and protein content in grains face limitations in DNA extraction. Advanced molecular genetic techniques such as mapping and marker-assisted selection programs require pure and quick DNA extraction. In this study, we developed methods for isolating high-quality genomic DNA from leaves and seeds of major cereal crops with minor modifications. DNA yields ranged from 300 to 1800 ng for 0.01 g seed or leaf tissue.