A 2-year field experiment was conducted during 1990-91 and 1991-92 on a sandy-loam soil of Modipuram, tostudy the effect of summer legumes on growth and yield of maize (Zea mays L.) in rainy (kharif) season on wheat(Triticum aestivum L. emend. Fiori & Paol) in the winter (rabi) in a maize-wheat system. Summer cropping of groundnut(Arachis hypogaea L.), cowpea [Vigna unguiculata (L.) Walp.] for fodder and greengram, (Phaseolus radiatus L.) hadsignificant effect on growth, yield and its attributes and nitrogen uptake on maize. Grain yield recorded for maize grownafter groundnut was at par with that after cowpea (fodder), but was significantly higher over greengram and fallow plots.Increasing each level of nitrogen brought significant improvement in the growth and yield attributes and finally grainyield even up to 120 kg N/ha, though yield obtained with 80 and 120 kg N/ha were at par. Two years mean data showedthat summer legumes. could contribute nitrogen equivalent to 40-80 kg N/ha Summer cropping of groundnut andcowpea (fodder) significantly increase the grain yield of wheat compared with the greengram and fallow, only duringthe second year of experimeptation. Grain yield of wheat also increased significantly with increase in level of nitrogenup to 120 kg N/ha during both the years, though yield obtained with 120 and 80 kg N/ha was at par during second year.

Optimisation of the concentrations of essential mineral elements in staple grain diet and reduction in non-essential and potentially toxic elements would considerably alleviate mineral malnutrition and improve the health of humans. Here, wheat (Triticum aestivum L.) plants were biofortified with Zn and/or Se to determine the changes across 36 elements in the grain. The element concentrations were determined by multielemental k0-instrumental neutron activation analysis (k0-INAA). In comparison to grain from non-biofortified plants, Zn fertilisation increased the grain Zn, Ca, and Mo concentrations, whereas the foliar application of Se only increased the grain Se concentrations. Double biofortification (combined Zn fertilisation and foliar Se) was more effective for the increased Se concentrations in the grain, in comparison to the Se-only biofortified plants, with the grain Zn, Ca and Mo concentrations remained at the same levels as those for the Zn-only biofortified plants. Except for Ba, Br and Rb, the concentrations of the elements analysed were below the detection limits. Double biofortification might be a feasible strategy to efficiently coordinate the mineral quality of wheat grain, although the considerable concentrations of other essential and non-essential elements should not be neglected.

An aggregated distribution pattern of weed populations provides opportunity to reduce the herbicide application if site-specific weed management is adopted. This work is focused on the practical testing of site-specific weed management in a winter wheat and the optimisation of the control thresholds. Patch spraying was applied to an experimental field in Central Bohemia. Total numbers of 512 application cells were arranged into 16 blocks, which allowed the randomisation of four treatments in four replications. Treatment 1 represented blanket spraying and the other treatments differed by the herbicide application thresholds. The weed infestation was estimated immediately before the post-emergence herbicide application. Treatment maps for every weed group were created based on the weed abundance data and relevant treatment thresholds. The herbicides were applied using a sprayer equipped with boom section control. The herbicide savings were calculated for every treatment and the differences in the grain yield between the treatments were tested using the analysis of variance. The site-specific applications provided herbicide savings ranging from 15.6% to 100% according to the herbicide and application threshold used. The differences in yield between the treatments were not statistically significant (P = 0.81). Thus, the yield was not lowered by site-specific weed management.

This study aimed to investigate seed germination, seedling growth, and antioxidative responses in two wheat cultivars, Ningchun and Xihan, exposed to different H2O2 concentrations. Ningchun exhibited higher germination rate but lower root and shoot growth than Xihan when exposed to H2O2 treatment. Assays using fluorescent dye H2DCFDA and propidium iodide showed a significantly enhanced H2O2 content and a cell elongation inhibition in H2O2-treated roots. The malondialdehyde content was elevated with increasing exogenous H2O2 concentration. Moreover, treatments of seedlings with H2O2 scavenger, catalase (CAT), and antioxidant, butylated hydroxytoluene, partly abolished H2O2-induced negative effect on root growth. In both untreated and H2O2-treated leaves, SOD activity in Ningchun was higher than that in Xihan, but POD and APX activities in Ningchun were lower than those in Xihan, leading to elevated H2O2 level in Ningchun leaves but decreased H2O2 content in Xihan ones under H2O2 treatment.

A composite durum wheat population (Triticum turgidum, 2n=4X=28, A and B genomes) was created by crossing elite durum lines with wild (T. dicoccoides) and primitive emmer (T. dicoccum) accessions. A recessive male sterility gene was used in order to monitor the outcrossing rate in the population. Since 1997, this population is experiencing each year natural and anthropic selection with an outcrossing rate of 10 %. The EPO project aims at identifying SNPs from 100 fixed lines extracted from this important resource of diversity and to evaluate the potential of RNA seq for Genotyping by sequencing purposes. [br/] We obtained transcriptomics data for 50 individuals and built contigs using those data and standard NGS pipelines. As expected for a allotetraploid species, this first rough analysis demonstrated that for a large number of detected SNPs an excess of heterozygosity was observed. This seems to indicate that the simultaneous expression of the two A and B homeologous copies of many genes resulted in an erroneously merge of paralogous/homeologous sequences. This clearly pinpoints that such standard assembly protocols are not adapted do deal with polyploid species. [br/] We thus developed a dedicated assembly strategy that exploits strict and accession specific assemblies and Triticum monococcum and Aegilops speltoides diploids genomes to identify paralogs and homeologs in the durum wheat A and B genomes. This approach significantly increases the number of unambiguous within genome polymorphisms and offer promising perspective for genotyping by sequencing durum wheat and other polyploids of agronomic importance.

Treatment with 0.5 mM salicylic acid (SA) significantly alleviated growth inhibition induced by drought in wheat seedlings, manifested by less decreassed fresh mass, dry mass, plant height, root length, and less increased lipid peroxidation. Under drought stress, SA significantly increased the content of ascorbate (ASA) and glutathione (GSH). We determined the full-length cDNA sequences of genes encoding the glutathione-S-transferase 1 (GST1) and 2 (GST2) and we also measured the transcription of eight genes related to ASA-GSH cycle. The results indicated that exogenous SA significantly enhanced the transcription of GST1, GST2, glutathione reductase (GR), and monodehydroascorbate reductase (MDHAR) genes during almost the entire drought period, but only increased those of dehydroascorbate reductase (DHAR) at 12 h, glutathione peroxidase (GPX1) at 48 h, phospholipid hydroperoxide glutathione peroxidase (GPX2) at 12 and 24 h, and glutathione synthetase (GSHS) at 12, 24, and 48 h. This implies that SA alleviates the detrimental effects of drought stress on wheat seedling growth by influencing the ASA-GSH cycle.

The starch proportion, starch granule distribution, and activities of enzymes involved in starch synthesis in different spikelet positions were examined during grain development in two high-yielding winter wheat cultivars. The results showed that grain number and weight per spikelet in different spatial position showed a single-peak curve from the base to the top in a wheat spike. Upper spikelets had the highest starch and amylose proportion followed by basal spikelets, whereas middle spikelets had the lowest. Starch and amylose absolute content was in opposition to their proportion. The volume of B- and A-type granule in grain of middle spikelets was remarkably higher and lower than those of basal and upper spikelets, respectively. However, no significant difference occurred in the number of A- and B-type granule in grains among different spikelet position. Compared with the basal and upper spikelets, the middle spikelets showed higher sucrose and ATP content and activities of starch biosynthetic enzymes, and subsequently higher starch absolute content. The results suggested that superior sucrose providing and degradation capacity and the high activities of enzymes involved in starch synthesis resulted in development of B-type starch granule in grain of middle spikelets.

To investigate the effects of returning wheat straw to croplands on soil compaction and nutrient availability, this trial was designed: (1) planted crops without fertilization (NF); (2) natural land without human activities (CT); (3) applied mineral fertilizers in combination with 7500 kg/ha wheat straw (WS-NPK); (4) applied mineral fertilizers in combination with 3750 kg/ha wheat straw (1/2WS-NPK); and (5) applied mineral fertilizers alone (NPK). It is found that, compared with NPK, the soil bulk density in 1/2WS-NPK and WS-NPK both decreased by more than 10% in the 0 cm to 15 cm layer, and by 6.93% and 9.14% in the 15 cm to 20 cm, respectively. Furthermore, in contrast to NPK, the soil available nitrogen in the 0 cm to 25 cm layer in 1/2WS-NPK and WS-NPK were higher by 17.43% and 35.19%, and the soil available potassium were higher by 7.66% and 17.47%, respectively. For soil available phosphorus in the depth of 5 cm to 25 cm, it was higher by 18.51% in 1/2WS-NPK and by 56.97% in WS-NPK, respectively. Therefore, returning wheat straw to croplands effectively improves soil compaction and nutrients availability, and the improvement in soil nitrogen and phosphorus availability is closely related to the amount of wheat straw.

O uso da irrigação na triticultura tem aumentado significativamente nos últimos anos no Brasil. Neste trabalho, objetivou-se avaliar a influência da irrigação na produtividade, na qualidade tecnológica da farinha e no sistema radicular do trigo. Em experimento de campo no IAPAR, em Londrina, Paraná, a cultivar IPR 118 foi cultivada sob irrigação por aspersão convencional (Tratamento Irrigado) e sem irrigação (Tratamento Sequeiro). A produtividade foi determinada, colhendo-se três amostras de 25 m² por tratamento. Nestas mesmas amostras, procedeu-se à análise da qualidade tecnológica da farinha, sendo avaliada, entre outros parâmetros, a força de glúten (W). A avaliação do sistema radicular foi realizada após a colheita, no perfil de 0 a 45 cm de profundidade do solo, amostrando-se oito plantas em cada tratamento. O método da parede do perfil foi utilizado para determinar o número de raízes (NR) e o método do monólito para determinar a massa seca de raízes (MSR). A irrigação aumentou em três vezes a produtividade do trigo, porém diminuiu o W na farinha. Ainda assim, o valor de W encontrado no Tratamento Irrigado (249 10-4 J) foi suficiente para manter a classificação do trigo como tipo-pão, a mesma para o qual a cultivar IPR 118 é classificada. Os valores medidos de NR e a MSR foram iguais ou maiores no Tratamento Sequeiro. | The use of irrigation has been increased significantly in wheat crops in Brazil. This study aims to evaluate the effect of irrigation on the productivity, on flour technological quality and on the wheat root system. In a field experiment conducted at IAPAR, in Londrina -state of Paraná (PR), Brazil, the IPR 118 cultivar was grown under sprinkler irrigation (Irrigated Treatment) and without irrigation (Non-irrigated Treatment). The productivity was determined by harvesting three samples of 25 m² per treatment. The same samples were used to evaluate the flour technological quality, considering, among other parameters, gluten strength (W). The evaluation of the root system was performed after the harvest, considering a profile of 0 to 45 cm of soil depth, and sampling eight plants per treatment. The profile wall method was used to determine the roots number (RN) and the monolith method to determine the root dry mass (RDM). Irrigation increased wheat productivity in three times, while W was reduced in the flour. Nevertheless, the value of W found in the Irrigated Treatment (249 10-4 J) was sufficient to keep wheat classification as bread type, the same as IPR 118 cultivar is classified. The measured values of RN and RDM were similar or higher for the Non-irrigated Treatment.