Bread wheat, the main crop of the Indo-gangetic plains of India faces a major threat (biotic and abiotic) to stability of production on account of its monoculture. Results on performance of triticale varieties developed at Punjab Agricultural University are presented and their role in diversifying and stabilising this agro-ecosystem is discussed. Triticale performed better or at par with best wheat varieties under normal growing conditions but had a clear edge over wheat in drought stress environments. Observations on disease resistance show triticale to be highly resistant to major wheat diseases. It is proposed that triticale would have a two-fold effect in improving the stability and sustainability of the agro-ecosystem. One, the area under triticale interspersed in the wheat acreage would destroy the monoculture. Two, being itself extremely tolerant to diseases like rusts and bunts and at the same time being hardy and drought tolerant, triticale cultivation would further enhance the stability of the system.

Studies on triticale as a cereal for grain have been carried out since 1975 in the Northeast of Portugal. Because of its high biomass production, triticale has also been studied as a forage crop since 1979. These studies were designed to investigate whether rye, the major cereal in that region which sometimes is grown as a forage crop or oats, sown in cereal-legume mixtures, could advantageously be replaced by triticale.According to previous data, the line UTAD 36/85, from the UTAD triticale breeding programme, and the Polish cultivar Presto were selected for studying the effect of the seeding rate on forage yield and quality. The regional rye population Vila Pouca and the Portuguese oats cultivar Boa-Fe were used as testers.Dry matter yield, forage quality (in vitro organic dry matter digestibility and crude protein content) and number of stems, m(-2) were evaluated at the seeding rates of 175, 350, 525 and 700 viable seeds.m(-2). Over all variables, triticale line UTAD 36/85 had the highest mean of dry matter yield (8715 kg.ha(-1)) while the regional rye population Vila Pouca had the lowest (7315 kg.ha(-1)). At the rates of 175 and 350 viable seeds.m(-2) the average number of stems. m(-2) for all genotypes was similar but it increased with higher rates. The highest in vitro organic matter digestibility was observed on triticale cv. Presto, 66.6% at the seeding rate of 175 viable seeds.m(-2), and the lowest on oats cv. Boa-FC, 52.8% at the same seeding rate. The highest crude protein content was observed for all seeding rates on the rye population while the oats cultivar showed the lowest one.

The parental origin of all chromosomes present in Triticale X Tritordeum (AABBRH(Ch), 2n=6X=42) F-1 hybrids was established in metaphases using fluorescence in situ hybridization technique with cloned, repetitive DNA probes and total genomic DNA. Total genomic nle DNA can be used as a probe re, label the seven rye-origin chromosomes strongly and uniformly along their lengths and telomeric regions. The seven Hordeum chilense-origin chromosomes and the 28 wheat-origin chromosomes were labelled weakly and almost undetectably, respectively. In contrast, when total genomic Hordeum chilense DNA was used as a probe, under the same conditions, the seven H. chilense and rye-origin chromosomes were strongly labelled and the wheat-origin chromosomes showed a weak in situ hybridization signal. Cloned and repetitive DNA probes of rye (pSc200) and H. chilense (pHcKB6) enabled all their own-species chromosomes to be identified in the F-1 hybrids. The in situ hybridization patterns analysis of several probes used on prophase and interphase nuclei showed that the different parental origin chromosomes did not lie randomly, but were located in one to three different domains. The fluorescence in situ hybridization technique is a useful molecular cytogenetic method on the identification of the different parental origin chromosomes present in these hybrids not only in metaphase but also at other stages of cell cycle.

Primary octoploid triticale have been produced by crossing GA(3) sensitive tall wheats with a GA(3) insensitive dwarf (ct2) rye as well as a GA(3) insensitive dwarf (Rht3) wheat with a GA(3) sensitive tall rye. After colchicine treatment and vegetative multiplication of the hybrids, grains were harvested and cytologically checked. Then a GA(3) seedling test was conducted. Whereas the triticales carrying the dominant Rhf3 dwarfing gene of wheat showed the expected GA(3) insensitivity, the triticales with the recessive ct2 dwarfing gene were GA(3) sensitive. Final plant heights were as expected from the results of the GA(3) test. It was suggested that the expression of ct2 is affected by genomic interactions between wheat and rye.