Productivity and stability of grain yield in maize and sorghum as affected by rotational cropping systems in the north western Free State

The physiography, geology, soil, land types and climate of the north-western Orange Free State are described. The description provides a contextual framework for the subsequent vegetation classification.

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Dry matter accumulation and partitioning and its relationship to grain yield in wheat

Australian Journal of Experimental Agriculture ◽

10.1071/ea9950495 ◽

1995 ◽

Vol 35 (4) ◽

pp. 495 ◽

Cited By ~ 10

Author(s):

RG Flood ◽

PJ Martin ◽

WK Gardner

Keyword(s):

Grain Yield ◽

Dry Matter ◽

Grain Filling ◽

Dry Matter Accumulation ◽

The North ◽

Similar Range ◽

Total Crop ◽

Grain Filling Period ◽

Stem Reserves ◽

North Western

Total crop dry matter (DM) production and its components, remobilisation of stem reserves, and the relation of these to grain yield were studied in 10 wheat cultivars sown at Walpeup, Boort, and Horsham in the north-western Victorian wheatbelt. Between sites, all DM components decreased in the order Horsham > Boort > Walpeup. Differences between Boort and Walpeup were not always significant. Total DM at anthesis for Walpeu,p and Boort was in a similar range, and less than that for Horsham. Yields increased in the order Walpeup < Boort < Horsham. When data from the 3 sites were combined, leaf, stem (excluding cv. Argentine IX), and total DM were related to grain yield. Within sites, ear DM at anthesis was related to grain yield. Grain yield for all cultivars at Horsham and Walpeup and 5 cultivars at Boort was greater than the increases in crop DM from anthesis to maturity, indicating that pre-anthesis stored assimilates (stem reserves) were used for grain filling. Post-anthesis decrease in stem weight was inversely related to grain yield only at Horsham, which supports the view of utilisation of stem reserves for grain filling at this site. At Boort and Walpeup there was a similar negative trend, but values for 2 cultivars at each site were outliers, which weakened the trend. The wide adaptability of the Australian cultivars used in this study may be related to the differential remobilisation of stem reserves at each site. A measure of yield stability, however, was not related to stem weight loss during the grain-filling period.

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Modeling Water and Nitrogen Balance of Different Cropping Systems in the North China Plain

Agronomy ◽

10.3390/agronomy9110696 ◽

2019 ◽

Vol 9 (11) ◽

pp. 696 ◽

Cited By ~ 5

Author(s):

Shah Jahan Leghari ◽

Kelin Hu ◽

Hao Liang ◽

Yichang Wei

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

North China Plain ◽

North China ◽

Cropping Systems ◽

Summer Maize ◽

The North ◽

The North China Plain ◽

Spring Maize ◽

N Use

The North China Plain (NCP) is experiencing serious groundwater level decline and groundwater nitrate contamination due to excessive water pumping and application of nitrogen (N) fertilizer. In this study, grain yield, water and N use efficiencies under different cropping systems including two harvests in 1 year (winter wheat–summer maize) based on farmer (2H1Y)FP and optimized practices (2H1Y)OPT, three harvests in 2 years (winter wheat–summer maize–spring maize, 3H2Y), and one harvest in 1 year (spring maize, 1H1Y) were evaluated using the water-heat-carbon-nitrogen simulator (WHCNS) model. The 2H1YFP system was maintained with 100% irrigation and fertilizer, while crop water requirement and N demand for other cropping systems were optimized and managed by soil testing. In addition, a scenario analysis was also performed under the interaction of linearly increasing and decreasing N rates, and irrigation levels. Results showed that the model performed well with simulated soil water content, soil N concentration, leaf area index, dry matter, and grain yield. Statistically acceptable ranges of root mean square error, Nash–Sutcliffe model efficiency, index of agreement values close to 1, and strong correlation coefficients existed between simulated and observed values. We concluded that replacing the prevalent 2H1YFP with 1H1Y would be ecofriendly at the cost of some grain yield decline. This cropping system had the highest average water use (2.1 kg m−3) and N use efficiencies (4.8 kg kg–1) on reduced water (56.64%) and N (81.36%) inputs than 2H1YFP. Whereas 3H2Y showed insignificant results in terms of grain yield, and 2H1YFP was unsustainable. The 2H1YFP system consumed a total of 745 mm irrigation and 1100 kg N ha–1 in two years. When farming practices were optimized for two harvests in 1 year system (2H1Y)OPT, then grain yield improved and water (18.12%) plus N (61.82%) consumptions were minimized. There was an ample amount of N saved, but water conservation was still unsatisfactory. However, considering the results of scenario analyses, it is recommended that winter wheat would be cultivated at <200 mm irrigation by reducing one irrigation event.

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