Genetic variation for dry matter and nitrogen accumulation and translocation in two-rowed spring barley: I. Dry matter translocation

A 4-year field study was carried out to determine dry matter and nitrogen accumulation until anthesis and at grain filling period and dry matter translocation and utilization in grain filling of barley. Twenty two-rowed spring barley (Hordeum vulgare ssp. distichum L.) cultivars originated from different countries (Yugoslavia, Germany, Australia, the Czeck Republic, Netherlands, France and USA) were grown during 1995–1998 on a non-calcareous chernozem soil near Novi Sad (45° 20′N, 15° 51′E, 86 m asl). Dry matter and nitrogen accumulation depended on the cultivar and year. In a year with favorable weather conditions, 58% of dry matter was accumulated during pre-anthesis, while in a year with less favorable weather the amount was 48%. In the favorable year 91% and in unfavorable year 65% of nitrogen was accumulated until anthesis. The results indicated that the greater amount of dry matter and nitrogen accumulated before anthesis. Dry matter translocation efficiency depended on the cultivar and ranged from 3 to 16.4%, while the contribution of pre-anthesis assimilates to kernel varied from 4 to 24.2%. Cultivars that have been developed for the growing conditions of the area where the experimental site was located, i.e. adapted ones, did not use pre-anthesis dry matter for grain filling. High positive correlations (P<0.01) were found between biomass at anthesis and biological yield, dry matter translocation efficiency, contribution of translocated dry matter to grain yield, and total plant nitrogen at maturity. Accumulated nitrogen at anthesis was positively correlated (P<0.01) with growing degree–days until anthesis, dry matter at anthesis and dry matter translocation parameters. Heritability for the investigated characters was rather high, over 0.60.     

Comparative performance of winter and spring malting barleys in semiarid growing conditions

In Europe, during the 1960s, mainly two-rowed spring barley was used for malting. Traditionally, spring malting barley was produced in regions with moderate temperatures and adequate rainfall throughout the growing season. Winter malting barley, on the other hand, was mostly grown in the milder arid and semiarid parts of Europe. Due to global climatic changes and its higher yield, winter malting barley is now increasing in acreage in the traditional spring barley regions. Our study included a comparative analysis of several grain and malt characters of the winter and spring malting barley grown under the agroecological conditions of the Vojvodina Province, Yugoslavia. One thousand grain weight was shown to be approximately the same for both growth habits, whereas winter malting barley proved to have a higher hectoliter mass than the spring one. In those years that were less favorable for spring barley production, winter malting barley had better quality characters, namely a higher fine extract content, a better malt modification, and a lower malt protein content. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic variation for dry matter and nitrogen accumulation and translocation in two-rowed spring barley II. Nitrogen translocation

An understanding of the partition between pre-anthesis and post-anthesis N uptake and their contribution to total grain N and protein content in spring two-rowed barley (Hordeum vulgare spp. distichum L.) is important to achieve additional breeding progress for both fodder and malting barley. N translocation from the vegetative tissues at anthesis to the kernel, N translocation efficiency, and N harvest index (NHI) were studied in field experiments during 4 years (1995–1998). Plants were harvested at anthesis and maturity and divided into leaf+culm, chaff and grain. Significant cultivar differences in N translocation, N translocation efficiency and NHI were determined. Across cultivars, the highest N translocation was in a favorable year (93 kg ha⁻¹) and the lowest in a year with poor growing conditions (40 kg ha⁻¹). Cultivar differences in N translocation were related to dry matter and pre-anthesis N accumulation (R²>0.70). N translocation efficiency varied more among the cultivars (0.27–0.66) than years (0.47–0.52). Post-anthesis N uptake was negatively correlated (P<0.01) with N translocation. NHI ranged among the cultivars from 0.49 to 0.73 and among the years from 0.57 to 0.74. The cultivars Arapiles, Schooner, Cantala, Kaskade and Pek stored in the grain more than 70% and Hiproly less than 50% of above-ground N at maturity. Translocated N participated with 85, 56, 42, and 61% in grain N in 1995, 1996, 1997, and 1998, respectively. The ratio of translocated N to grain N could be an indicator of growing conditions; a higher ratio indicates good growing conditions over the entire growth period, a lower ratio indicates poor conditions during pre-anthesis, and a medium ratio indicates some temperature and water deviations from the long-term average. Straw N concentration was in significant positive (P<0.01) correlation with N translocation and translocation efficiency. Straw N concentration adequately represents N efficiency utilization for synthesis of grain protein, and because it saves time and money compared to N harvest index determination, it can be used for the testing of breeding materials for the development of new barley cultivars.