A two-year field experiment with a split-split plot design was conducted to investigate the effects of soil N(0, 120 and 240 kg N·ha−1) and foliar Zn applications at different growth stages (jointing, flowering, early grain filling, and late grain filling) on Zn translocation and utilization efficiency in winter wheat grown on potentially Zn-deficient soil. Our results showed that foliar Zn application at the early grain filling stage significantly increased the Zn concentration in the grain (by 82.9% compared to control) and the Zn utilization efficiency (by 49% compared to jointing). The Zn concentration in the straw consistently increased with the timing of the foliar Zn application and was highest at late grain filling. However, the timing of the Zn application had little effect on Zn uptake in the grain and straw. A high N supply significantly increased the Zn concentration in and uptake by grain and straw, but it had little effect on the efficiency of Zn utilization. Consequently, a foliar Zn application at early grain filling causes Zn to re-translocate into grain from vegetative tissues, resulting in highly nutritional wheat grain. Finally, these practices improved the efficiency of Zn utilization in winter wheat and led to Zn-enriched straw, which may contribute to Zn recycling if it is returned to the field. The results also indicated that N nutrition is a critical factor in both the concentration and translocation of Zn in wheat.
The objective of this work was to determine the change for straw production, carbon and ash content in vegetative tissues through ten cycles of recurrent selection in bread wheat, evaluated under tilled (CT) and non-tilled (NT) soils. Twenty-four wheat genotypes, four for each one of the 0, 2, 4, 6, 8 and 10 cycles of recurrent selection (RS), were used in this study. Experiments were established during two successive seasons. Ash content was expressed on dry mass basis. To estimate the carbon content, we based our calculation on the assumption that organic matter is 50% carbon. Straw dry weight was measured. For each trait, a linear mixed model (regression) was fitted to the experimental data. In response to the number of selection cycles, the ash content percentage increased under CT and decreased under NT. Carbon content decreases under CT, but increases under NT. The sequestered straw carbon and the straw production significantly decrease under CT meanwhile there was no change under NT. The observed increase for straw ash content would be related to the highest rate of transpiration in the more advanced recurrent selection cycles. Consistent with these results, the percentage of straw carbon content decreased because of the mobilization of reserves from the stems and leaves to the grains.
The sustainable production of wheat may be possible by integrating crop rotation with improved crop management practices. The maximum grain yield of wheat was observed when field pea was the precursor crop. The precursor crop and management levels showed a significant effect on the mean straw and grain yields of wheat. Field pea as precursor crop gave a better wheat grain yield with both improved and farmers' cultural practices. Both local and improved varieties gave a better response to management levels on the field pea precursor field. Local and improved varieties gave higher yields with intensive management and chemical fertilizer application. Field pea as precursor crop gave a combined grain yield advantage of 32% relative to barley. Management practices produced a combined grain yield advantage of 16 to 73% when field pea was the precursor crop, compared to barley. The use of field pea as precursor crop with improved management practices is essential to maximize wheat yields. Better grain yields and higher net returns were achieved with field pea as precursor crop compared to barley. Using field pea as precursor crop is the most successful management option for sustainable wheat production.
Authors:R. Kundu, K. Bhattacharyya, A. Majumder, and S. Pal
Arsenic, the toxic metalloid, widely available in the natural ecosystem, poses serious problem through contaminated groundwater and drinking water. The emerging areas of arsenic hazards in agricultural systems through use of contaminated irrigation water and entry of toxin in crops has been largely overlooked. Arsenic accumulation by plants and its translocation to edible parts were observed to vary within crops and also across the cultivars. Wheat is an alternative choice of summer rice, due to low water requirement. With this background, the current experiment was conducted with four popular wheat cultivars to study the arsenic accumulation and varietal tolerance under different soils and groundwater. The arsenic content was determined by using atomic absorption spectrophotometer (AAS). Result revealed that, wheat cultivars differed in their grain arsenic concentration (0.23–1.22 mg kg−1), which differed across the sites and year of experiment. The arsenic translocation in wheat grains usually least, and accumulation by different tissues followed the order root > stem > leaf > grain across the cultivars. The cultivar UP-262 was found to accumulate least arsenic in grains and cultivar Kalyansona the highest under same growing condition, due to phyto-extraction or phyto-morphological potential of the varieties.
Hoffman, S., Csitári, G., Balázs, J., Banko, J., Banko, L. 2005. Impact of straw manuring on soil organic matter dynamics and fertility. In: International Conference on the Role of Long-term Field Experiments in Agricultural and Ecological Sciences. Book