Effect of climate variables on yield of major food-crops in Nepal -A time-series analysis-

Climate change influences crop yield vis-à-vis crop production to a greater extent in countries like Nepal where agriculture depends largely on natural circumstances. Plausible scenarios of climate change like higher temperatures and changes in precipitation will directly affect crop yields. Therefore, this study assesses the effect of observed climate variables on yield of major food-crops in Nepal, namely rice, wheat, maize, millet, barley and potato based on regression model for historical (1978-2008) climatic data and yield data for the food-crops. The yield growth rate of all the food-crops is positive. However, the growth rate for all crops, except potato and wheat, is below population growth rate during the period. Climate variables like temperature and precipitation are the important determinants of crop yields. Trend of precipitation is neither increasing nor decreasing significantly during this period. However, temperature is increasing by 0.7 0C during the period. Climate variables show some influences on the yield of these major food-crops in Nepal. Increase in summer rain and maximum temperature has contributed positively to rice yield. Also, increase in summer rain and minimum temperature has positive impact on potato yield. However, increase in summer rain and maximum temperature adversely affected the yield of maize and millet. Increase in wheat and barley yield is contributed by current trend of winter rain and temperature. Consideration of spatial variation in similar type of study in Nepal that will be helpful in identifying the region more vulnerable to climate change in terms of crop yield is highly recommended.Climate variables; temperature; rainfall; food-crops; Nepal

Vessel-specific reintroduction of CINNAMOYL-COA REDUCTASE1 (CCR1) in dwarfed ccr1 mutants restores vessel and xylary fiber integrity and increases biomass

Lignocellulosic biomass is recalcitrant toward deconstruction into simple sugars due to the presence of lignin. To render lignocellulosic biomass a suitable feedstock for the bio-based economy, plants can be engineered to have decreased amounts of lignin. However, engineered plants with the lowest amounts of lignin exhibit collapsed vessels and yield penalties. Previous efforts were not able to fully overcome this phenotype without settling in sugar yield upon saccharification. Here, we reintroduced CINNAMOYL-COENZYME A REDUCTASE1 (CCR1) expression specifically in the protoxylem and metaxylem vessel cells of Arabidopsis (Arabidopsis thaliana) ccr1 mutants. The resulting ccr1 ProSNBE: CCR1 lines had overcome the vascular collapse and had a total stem biomass yield that was increased up to 59% as compared with the wild type. Raman analysis showed that monolignols synthesized in the vessels also contribute to the lignification of neighboring xylary fibers. The cell wall composition and metabolome of ccr1 ProSNBE: CCR1 still exhibited many similarities to those of ccr1 mutants, regardless of their yield increase. In contrast to a recent report, the yield penalty of ccr1 mutants was not caused by ferulic acid accumulation but was (largely) the consequence of collapsed vessels. Finally, ccr1 ProSNBE: CCR1 plants had a 4-fold increase in total sugar yield when compared with wild-type plants

Potential of Pyrolysis for valuable products obtaining from wheat straw lignin produced by CIMV technology

Two configurations of fast pyrolysis realized in flowing (inert gas flow) and ablative-type reactors were used for phenolic fraction obtaining. The maximum yield of phenolic compounds was achieved at 450 degrees of Celsius in the case of ablative reactor usage (7,6%). Application of catalysts (Na+ and K+) allowed to increase the yield of phenolic compounds up to 8,5%

Influence of alleycropping microclimate on the performance of groundnut (Arachis hypogaea L.) and sesame (Sesamum indicum L.) in the semi-desert region of northern Sudan

An alley cropping system was established at Hudieba Research Station (17.57’N and 33.8’ E) on a loamy sand soil of the semi-desert region of northern Sudan. The objective of this study was to investigate the influence of modified microclimate in 6-m wide alleys formed by Acacia ampliceps and Acacia stenophylla on growth and yield of groundnut. and sesame. Above-ground interactions were determined by measuring air temperature, relative humidity, wind speed, solar energy and shade length and behaviour. Groundnut and sesame were evaluated for growth and yield by laying out sample plots at southern, central and northern part of the alleys and at control plots. Due to microclimatic modifications in the alleys, the yield of both crops in the alleys significantly (p=0.01) exceeded that of the sole crop. Yield reduction at the northern alley was fully compensated by high yield increase at southern and central alleys. The yield of groundnut increased by 37.7 and 19.6 % in the A.stenophylla and A.ampliceps alleys, respectively. On the other hand, the yield of sesame increased with the stenophylla-alley (+40.3%), while it decreased with ampliceps-alley (-51.5%). The results indicated that the competition for light was the major factor contributing to the increase or reduction of growth and yield of groundnut and sesame

Responses of grain yield, biomass and harvest index and their rates of genetic progress to nitrogen availability in ten winter wheat varieties.

peer-reviewedIncreased yields in winter wheat cultivars have been found to be largely attributable to improved partitioning of biomass to the grain, i.e., higher harvest index. However, there is a biological upper limit to harvest index and therefore breeders need to exploit increased biomass production as the mechanism by which yields are increased. Evidence for improved biomass was sought in experiments conducted over three years (1994 to 1996), at the Plant Testing Station, Crossnacreevy, near Belfast, with 10 varieties of winter wheat introduced over the period 1977 to 1991. Variation in grain yield was more strongly associated with variation in biomass (an increase of 0.78 t/ha in grain yield at 85% dry matter (DM) per 1t/ha increase in biomass at 100% DM; R2 = 0.71) than in harvest index (an increase of 0.1t/ha at 85% DM per percentage point increase in harvest index; R2 = 0.36). When age (= year of first harvest in UK National List trials) of the varieties was taken into account, yield (0.037 t ha−y−; R2 = 0.42) and biomass (0.034 t ha−y−; R2 = 0.31), but not harvest index (0.34%/year; R2 = 0.001), increased as year increased. Genetic gain in yield was smaller without fertiliser N (0.021 t ha−y−; R2 = 0.21) and at 40 kg ha N (0.025 t ha−y−; R2 =0.25) than at 215–250 kg/ha N (0.065 t ha−y−; R2 = 0.39). Theoretically, if the maximum biomass (18.60 t/ha for Rialto), could have been combined with the maximum harvest index (55.3%) in Riband, yield would potentially have been increased by 2.5 t/ha compared with yields for either variety.Advice and guidance from Dr. Sally Watson, Biometrics Branch, Agri-Food and Biosciences Institute is appreciated

Growth and Yield of Tomato Applied with Silicon Supplements with Varying Material Structures

The effect of varying material structure of silicon (Si) supplements on the growth and yield performance of tomato was investigated. The experimental design consisted of three Si sources (nanosilica, microsilica and sodium silicate) at 5 g/L Si concentration. Among the treatments, nanosilica posted the highest increase in tomato plants\u2019 height increment, fresh weights and dry weights of all plant organs, Si concentrations, and yield. Tomato plants grown with nanosilica had increased height increment and fresh weights of roots, stems and leaves by 23%, 48%, 9% and 22%, respectively. Likewise, dry weight contents among individual organs of plants treated with nanosilica showed 40% and 34% significant increase in roots and stems, respectively. Only nanosilica significantly increased the average fruit yield of tomato by 35% as affected by the 23% increase in the average number of fruits per plant. hence, among the treatments investigated, Si supplementation using nanosilica powder is the most effective in improving the growth characteristics and yield of tomato. Si in root samples supplemented with nanosilica was 72%, 105% and 152% larger as compared to microsilica, sodium silicate and control samples, respectively, which led to the conclusion that the nanostructured scale of silicon supplement contribute to the effective uptake of silicon in the tomato plants, thereby improving growth and yield

Genotype and environment interaction on yield and quality parameters of organically grown winter wheat – Triticum aestivum L. genotypes

The interaction of genotype and environment upon yield and quality parameters of eight winter wheat (Triticum aestivum L.) genotypes was studied under organic conditions in Austria over two growing periods, 2001/2002 and 2002/2003, respectively. Two sites that have significantly different climatic conditions, Innviertel and Marchfeld, were chosen for the field experiment. Study site weather and soil conditions are important yield-affecting factors. Although the yield of Marchfeld-grown genotypes were lower, they had shown higher quality parameter values. Soil moisture conditions increase the grain yield but decrease its quality. To obtain seed with higher quality, a production site with favourable climate conditions should be chosen

Have Biotech Seeds Increased Maize Yields?

Corn yield is determined by soils, weather, seed used and other technology choices. Global population and per capita income growth trends as well as demand from the energy sector have placed great stress on cropland use. Global cropland acres and/or yield per acre will need to increase. Whether new seed technologies have enhanced corn yield is a controversial issue. We study U.S. county corn yields 1964-2008, controlling for location effects, fertilization technologies and weather. We find evidence that trend yield growth has been fastest in the Central Corn Belt, genetic modification technologies have increased trend yield, and this increase has been largest in the Central Corn Belt.Biotechnology, Corn Yield, Trend, Regional Effects, Weather, Fertilization., Crop Production/Industries, Industrial Organization, Research and Development/Tech Change/Emerging Technologies, L65, Q16,