The use of plant genetic resources (PGR) in crop improvement, followed by adoption, cultivation and consumption or marketing of the improved cultivars by farmers, is one of the most sustainable methods to conserve valuable genetic resources for the future, and simultaneously to increase agricultural production and food security. The objective of this review is to summarize issues related to the use of PGR in crop improvement. Specific topics are: definition of genetic resources for crop improvement; information sources on the internet; documentation and evaluation of PGR; access to PGR, equitable sharing of profits, and material transfer agreements; impediments to the use of PGR in crop improvement; classical methods of using PGR in crop improvement (introgression, incorporation, prebreeding and wide crosses); use of landraces in breeding for specific adaptation to stress environments; utility of molecular markers and genomic research for using PGR in crop improvement (diversity assessment, mapping of quantitative trait loci (QTL) and marker-assisted selection (MAS), advanced backcross QTL analysis and introgression libraries, association studies and direct allele selection); and gene transfer. Practical examples or experimental results are given for most aspects.

A natural population of Vriesea friburgensis var. paludosa was genetically and demographically characterized. Four selected enzymatic systems were used. In total, 10 allozymic loci were analysed. The proportion of polymorphic loci was 70% and the number of alleles per locus was 2.3· The mean observed and expected heterozygosities were 0.234 and 0.226, respectively. An excess of heterozygotes was revealed by the value of the fixation index (—0.035). These indices showed the presence of high levels of genetic diversity in the population studied. A demographic survey revealed almost six times more vegetative than sexually reproductive plants. Reproductive plants were found only in clusters. The genetic diversity exhibited by this population, associated with vegetative as well as sexual propagation, resulting in clusters or colonies, would allow the employment of a sustainable management strategy for species conservation as well as its exploitation as an ornamental.

The concept of agro-sustainability is presented and discussed. The paper shows that sustainable farming practices, sustainable development and the preservation of biological diversity require adequate valorization of local biodiversity. Special emphasis is given to neglected and underutilized crop species. The role and importance of these plants, including primitive wheat, wild anise, food legumes, several vegetables and forage legumes in southern Italy is presented. Each case is presented as an example of cultivation linked to different aspects of utilization, conservation, genetic erosion, and of their potential for sustainable agriculture.

The technique of inter-simple sequence repeat-polymerase chain reaction (ISSR-PCR) was used to fingerprint blackgram (Vigna mungo) genotypes in order to differentiate them at a molecular level. Twenty-four primers were used to analyse 11 blackgram genotypes. The genotypes used in the study could be differentiated based on combined amplification profiles generated by two primers (UBC primer numbers 808 (AG)8C and 826 (AC)8C). It was observed that 3′-anchored repeat primers based on (AG) and (GA) repeats amplified a greater number of bands than 3′-anchored repeat primers of (CA) and (AC) repeats. This result perhaps indicates that GA/AG repeats are more frequent than CA/AC repeats in the blackgram genome.

The 17 Brazilian species of Adesmia DC were analysed, using 20 primers, with regard to their randomly amplified polymorphic DNA (RAPD) patterns. From a total of 357 individuals analysed, the 20 primers produced 2249 fragments with molecular sizes ranging from 200 to 2700 bp, 56% of which were polymorphic. Average intra-population genetic similarity, estimated by Jaccard's coefficient, ranged from 0.35 in A. araujoi to 0.80 in A. punctata. Mean intra-specific genetic similarity varied greatly among species, ranging from 0.19 for A. tristis to 0.89 for A. arillata. Mean genetic similarity among the species, estimated by Dice's coefficient, was 0.56. RAPD markers were efficient at separating all the accessions analysed. The results obtained generally agreed with the partition of genetic variability expected according to the mode of reproduction.

The technique of excised embryos was employed to facilitate the propagation of Podophyllum emodi derived from seeds collected at the different elevation zones of Himachal Pradesh, India. Seed germination was low, irrespective of stage of seed development or zone of collection. Germination was improved significantly (89.14%) in the partially mature and mature seeds collected from alpine and temperate zones when excised embryos were cultured on basal B5 medium. Leaf emergence and plant establishment in the field was also significantly higher in the plants raised through this technique, despite hypocotyl dormancy. The technique was successfully employed for the production of plants to be reintroduced in large numbers into their habitat in the Great Himalayan National Park.

Soft wheat (Triticum aestivum L.) improvement could be enhanced by the identification of germplasm with superior end-use quality traits. Due to the geographic and historical separation of eastern and western US soft wheat germplasm ‘pools’, genetic differences in end-use quality may exist among cultivars arising from these two pools. To identify such differences, 30 US soft wheat cultivars were evaluated in ‘head-to-head’ trials over 3 years in Washington state. Cultivars were classified as: eastern soft red winter (SRW), eastern soft white winter (ESWW), western soft white (WSWW) and western Club. These four soft wheat cultivar classifications clearly differed systematically for some of the quality traits examined. The Club wheat cultivar group had the highest flour yield and flour ash. The Club group also had the lowest mixograph dough water absorption. Milling score (which incorporates break flour yield) was highest for Club and ESWW. Eastern soft red and white wheat cultivar groups had lower flour ash and alkaline water retention capacity (AWRC) compared to the western Club and soft white wheats; ESWW had the lowest AWRC of any classification. Cookie diameter was greatest for the ESWW group, followed by the SRW and Club groups (which were not significantly different), and then by the WSWW group. Individual cultivars with exceptional quality traits were also identified. These results indicate that the four US soft wheat germplasm pools differ, and they may be valuable genetic resources for ‘inter-pool’ wheat improvement.