Milling & Grains bite-size science
Maize cultivar adaptation, endemic crop pests, lab milling
Late-maturing maize defies climate warming
Using adapted late-maturing cultivars of maize with longer growth durations, increased yield potential and increased water use efficiency (WUE), is an effective approach to managing food production in the warming environment, according to a team of Chinese scientists.
Adapted crop cultivars have already been identified as an effective solution to offset the effects of climate warming however there is limited knowledge about water use patterns of these cultivars, they report in Agricultural Water Management.
The researchers studied warming trends across the Loess Plateau in north-western China since 1960 and observed significant warming patterns, particularly since 1980.
Rising temperatures affect cyclic and seasonal phenomena, leading to a fall in crop yields, however the team suggests that planting adapted maize cultivars have prevented yield losses of up 1.83 tonnes per hectare (t ha) over the last 30 years.
Propagating the use of historical maize varieties can significantly decrease WUE across the Loess Plateau, the scientists wrote, but that based on ‘growing degree days’ (GDD) for each decade of their analysis, cultivating adapted later-maturing maize cultivars can improve productivity.
Late-maturing varieties were found to considerably extend the maize growing cycle by an average of 27 days, increasing yield potential by 24.2–64.8% and WUE by 9.0–38.1% throughout the Loess Plateau.
Source: Agricultural Water Management‘The effect of adapting cultivars on the water use efficiency of dryland maize (Zea mays L.) in northwestern China’DOI: 10.1016/j.agwat.2014.09.010Authors: Lingduo Bu, Xinping Chen, Shiqing Li, Jianliang Liu, Lin Zhu, Shasha Luo, Robert Lee Hill, Ying Zhao
Warning over spread of pests and pathogens
Global crop-growing countries may be overwhelmed by pests within 30 years if the current dispersal rate continues, say scientists at the University of Exeter.
Crop pests include fungi, bacteria, viruses, insects, nematodes, viroids and oomycetes, but it is the fungal pathogens that ‘lead the global invasion’, they say.
The study evaluated 424 crop pests and pathogens (CPPs), taken from the CABI distribution maps of plant pests and diseases between 2000 and 2011, with crop production data for 168 crops obtained from the UN Food and Agriculture Organization (FAO) to assess their global spread.
Researchers found relatively few CPPs restricted to a single region. Africa had 30 endemic CPPs, Asia 102, Europe 20, North America 28 and 29 in the Pacific. Pathogens had lower endemicity, with 9.5% of bacteria, 5.7% of fungi, 8.5% of oomycota and 14.8% of viruses restricted to one region.
Analyses showed that country pest saturation has increased linearly in the USA and China since the 1950s, when averaged over all regions. There was some variation noted, with deceleration in India and Great Britain in the same period, but Australia, China, France, India, Italy, the UK and the USA have all reached half of their saturated pest loads.
If these saturation rates persist into the future, then the USA, UK, Germany, Italy, France, Japan, India and China would have fully saturated pest distributions by 2050, they wrote.
Source: Global Ecology and Biogeography
Source: Global Ecology and Biogeography
‘The global spread of crop pests and pathogens’
DOI: 10.1111/geb.12214
Authors: Daniel P Bebber, Timothy Holmes, Sarah J Gurr
Effects of milling on wheat starch
Characterising the starch properties of wheat flour under different milling conditions allows producers to choose specific flour suitable for their food products.
Buhler laboratory mill and Brabender senior mill were used in a recent study to identify changes in the physical properties of starch in China’s leading soft and hard wheat varieties from the Northern China Plain Winter Wheat Region (Zhongmai 175 and Beijing 0045, respectively).
Researchers compared the damage to the starch content, granular morphology, crystallinity and functional properties of the two types of flour emerging from the different millstreams.
Results showed some fragmentation of starch granules, but no significant changes in the relative crystallinity in both streams although damaged starch content was shown to greatly influence the functional properties of starch granules in hard wheat, Beijing 0045.
More starch granules were damaged during laboratory milling of hard wheat Beijing 0045, whereas the degree of starch damage for soft wheat Zhongmai 175 was lower.
Damaged starch content was positively correlated with starch solubility and rapidly digested starch (RDS) content, but there was no significant correlation noted between damaged starch content and functional properties of starches from the different flour millstreams of soft wheat grain Zhongmai 175.
In conclusion, the two different milling processes had minimal effects on the properties of starches from straight run flour from the Buhler laboratory mill or the Brabender senior mill.
Source: Food Chemistry
‘Effect of laboratory milling on properties of starches isolated from different flour millstreams of hard and soft wheat’
DOI: 10.1016/j.foodchem.2014.09.070
Authors: Jinglin Yu, Shujun Wang, Jingrong Wang, Caili Li, Quanwei Xin, Wei Huang, Yan Zhang, Zhonghu He, Shuo Wang
