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Predicting aphid abundance on winter wheat using suction trap catches Полный текст
2020
Alois Honěk | Zdenka Martinková | Marek Brabec | Pavel Saska
Predicting aphid abundance on winter wheat using suction trap catches Полный текст
2020
Alois Honěk | Zdenka Martinková | Marek Brabec | Pavel Saska
The relationship between the number of cereal aphids in flight (recorded by a national grid of suction traps in the Czech Republic) and their occurrence on winter wheat (in Prague) was established between 1999-2015. The flight of all the species was bimodal. Except for Rhopalosiphum padi, whose flight activity peaked in autumn, > 80% of individuals were trapped during April to mid-August. The species frequency was different between the winter wheat and aerial populations. R. padi, the dominant species in the trap catches, formed a small proportion of the aphids on the winter wheat, while Sitobion avenae and Metopolophium dirhodum, which were underrepresented in the suction traps, alternately dominated the populations on the wheat. The aphid abundance in the wheat stands was correlated with the suction trap catches in the "spring" peak (April to mid-August), and the maximum flight activity occurred 4-10 days after the peak in the number of aphids on the wheat. In contrast, the prediction of the aphid abundance in the wheat stands using the total suction trap catches until the 15th of June (the final date for the application of crop protection actions) was reliable only for M. dirhodum. Its maximum abundance on the wheat exceeded 40 aphids per tiller if the total suction trap catch until the 15th of June was ≥ 60 individuals per trap. The prediction of R. padi and S. avenae abundance using the suction trap catches was not reliable.
Показать больше [+] Меньше [-]Predicting aphid abundance on winter wheat using suction trap catches Полный текст
2020
Honek, Alois | Martinkova, Zdenka | Brabec, Marek et al.
The relationship between the number of cereal aphids in flight (recorded by a national grid of suction traps in the Czech Republic) and their occurrence on winter wheat (in Prague) was established between 1999-2015. The flight of all the species was bimodal. Except for Rhopalosiphum padi, whose flight activity peaked in autumn, > 80% of individuals were trapped during April to mid-August. The species frequency was different between the winter wheat and aerial populations. R. padi, the dominant species in the trap catches, formed a small proportion of the aphids on the winter wheat, while Sitobion avenae and Metopolophium dirhodum, which were underrepresented in the suction traps, alternately dominated the populations on the wheat. The aphid abundance in the wheat stands was correlated with the suction trap catches in the “spring” peak (April to mid-August), and the maximum flight activity occurred 4-10 days after the peak in the number of aphids on the wheat. In contrast, the prediction of the aphid abundance in the wheat stands using the total suction trap catches until the 15th of June (the final date for the application of crop protection actions) was reliable only for M. dirhodum. Its maximum abundance on the wheat exceeded 40 aphids per tiller if the total suction trap catch until the 15th of June was ≥ 60 individuals per trap. The prediction of R. padi and S. avenae abundance using the suction trap catches was not reliable.
Показать больше [+] Меньше [-]63 Released Spring Bread Wheat, Durum Wheat and Winter Bread Wheat Varieties in 2020
2020
CGIAR Research Program on Wheat
Varieties have been released in one or more countries and are mad available to farmers for growing via NARS partners in country.
Показать больше [+] Меньше [-]Replication of long-term European winter wheat impact study for spring wheat in developing countries (WHEAT target geographies)
2020
CGIAR Research Program on Wheat
The variability of yield and baking quality of wheat and suitability for export from Nordic–Baltic conditions Полный текст
2020
Reine Koppel | Anne Ingver | Pille Ardel | Tiia Kangor | Hannah Joy Kennedy | Mati Koppel
Nordic conditions necessitate varieties adapted to marginal environments (short vegetation period, winter damages etc.) to reduce environmental influence on yield and quality. This study evaluated yield and quality variability of five spring and six winter wheat varieties grown in six locations throughout Estonia during 2011–2014. The variation of quality parameters was larger in spring wheat, according to the coefficient of variation. Average protein content for spring wheat was 13.6%, for winter wheat 13.3%. Average gluten content was 29.1% for spring wheat, 29.4% for winter wheat. Spring wheat varieties ‘Manu’ and ‘Quarna’ and winter wheat varieties ‘Ada’, ‘Fredis’, and ‘Ramiro’ had the highest baking quality. Protein and gluten content variation for both types of wheat depended mostly on the year. Baking strength W was higher for spring wheat. Variation of W of spring wheat depended more on genotype while variation of winter wheat more on year. The ratio of tenacity and extensibility (P/L) was similar for both wheat types; variation depended most on genotype. Average yield of winter wheat was 6.8 and spring wheat 5.3 t ha−1. ‘Nemunas’, ‘Kallas’, and ‘Skagen’ were high yielding among winter wheat varieties and had the best stability according to cultivar superiority index
Показать больше [+] Меньше [-]Mapping Winter Wheat in North China Using Sentinel 2A/B Data: A Method Based on Phenology-Time Weighted Dynamic Time Warping Полный текст
2020
Dong, Qi | Chen, Xuehong | Chen, Jin | Zhang, Chishan | Liu, Licong | Cao, Xin | Zang, Yunze | Zhu, Xiufang | Cui, Xihong
Accurate mapping of winter wheat over a large area is of great significance for guiding policy formulation related to food security, farmland management, and the international food trade. Due to the complex phenological features of winter wheat, the cloud contamination in time-series imagery, and the influence of the soil/snow background on vegetation indices, there remains no effective method for mapping winter wheat at a medium spatial resolution (10–30 m). In this study, we proposed a novel method called phenology-time weighted dynamic time warping (PT-DTW) for identifying winter wheat based on Sentinel 2A/B time-series data. The main advantages of PT-DTW include (1) the use of phenological features in two periods, i.e., the greenness increase before winter and greenness decrease after heading, which are common to all winter wheat and are distinct from the features of other land cover types, and (2) the use of the normalized differential phenology index (NDPI) instead of traditional vegetation indices to provide more robust vegetation information and to suppress the adverse impacts of soil and snow cover, especially during the before-winter growth period. The proposed PT-DTW method was employed for winter wheat mapping based on Sentinel 2A/B data on the Huang-Huai Plain, China. Validation with visually interpreted samples showed that the produced winter wheat map achieved an overall classification accuracy of 89.98% and a kappa coefficient of 0.7978, outperforming previous winter wheat classification methods. Moreover, the planting area derived from PT-DTW agreed well with census data at the municipal level, with a coefficient of determination of 0.8638, indicating that the winter wheat map produced at 20 m resolution was reliable overall. Therefore, the PT-DTW method is recommended for winter wheat mapping over large areas.
Показать больше [+] Меньше [-]EFFECTIVENESS OF BIOLOGIZATION TECHNIQUES IN LINKS OF CROP ROTATIONS WITH WINTER WHEAT IN THE FOREST-STEPPE ZONE OF THE VOLGA REGION Полный текст
2020
Morozov, V. I. | Toygildin, А. L | Podsevalov, М. I. | Ayupov, D.E.
The performance of the set tasks for the production of the necessary volumes of grain is possible only on the basis of a scientific-based approach to the development of agricultural technologies on a systematic basis. Research aim: to evaluate the effectiveness of methods of biologization of crop rotation links with winter wheat at the expense of grain legumes and organomineral fertilizer systems in conditions of forest-steppe zone of the Volga region. The research was carried out in years long stationary field trial of the department of agriculture, crop production and breeding of FSBEI HE Ulyanovsk SAU in 4-6-month field crop rotations. The objects of study were of crop rotation links with winter wheat: 1) complete fallow-winter wheat; 2) peas - winter wheat; 3) Lupin - winter wheat; 4) Lupin + peas - winter wheat. In the structure of land use, there is still a high share of complete fallow, which has negative environmental consequences. The main reason for the introduction of complete fallows is the preservation of moisture for seeding winter crops. However, our research shows that when replacing complete fallows to grain legumes (peas, white lupine), 23.0-25.0 mm of productive moisture accumulates in the soil before seeding winter wheat, which, if agrotechnical requirements are met, allows you to get seedlings and sufficient development of winter wheat in the autumn period. Despite the higher yield of winter wheat by complete fallow, the productivity of links with legumes was higher. The inclusion of grain legumes in crop rotations as steam-generating crops can be used to eliminate the negative effects of complete fallow. The results obtained allow us to recommend combined tillage that includes soil loosening for grain legumes and surface tillage for winter wheat, as well as to use the organomineral fertilizer system straw + NPK, while the doses of mineral fertilizers are calculated on the planned yield of grain legumes of 2.5-3.0 t/ha and winter wheat - 4.5 t/ha.
Показать больше [+] Меньше [-]The Application of Biostimulants on Winter Wheat Полный текст
2020
Hnilickova, Helena | Kraus, Kamil | Bezdickova, Alena et al.
One of the promising agrotechnical tools for the elimination of water stress appears to be the application of biostimulants for supporting plant growth at different stages of their development. The results of an experiment with different variants of biostimulants in three different genotypes of winter bread wheat are presented. After their application, a higher content of photosynthetic pigments was found in wheat with blue aleurone of grain and lower in wheat with multirow spike. The application of the biostimulants optimizes the physiological state of the plants in all tested genotypes, which is reflected in an increase in yield compared to the untreated control variant.
Показать больше [+] Меньше [-]Effects of Seven Diversified Crop Rotations on Selected Soil Health Indicators and Wheat Productivity Полный текст
2020
Lin Wang | Yingxing Zhao | Mahdi Al-Kaisi | Jia Yang | Yuanquan Chen | Peng Sui
Diversified cropping systems can enhance soil condition and increase system productivity worldwide. To reduce the negative effects that accompany the continuous winter wheat−summer maize (WM) double-cropping in the North China Plain (NCP), diversified crop rotation (DCR) needs to be considered. The objective of this study is to evaluate the effect of DCR on soil health and wheat productivity as compared to a continuous WM double-cropping. A field experiment (37°41′ N, 116°37′ E) was established in the NCP including a traditional WM double-cropping as a baseline. During 2016/2017−2017/2018, the control is winter wheat−summer maize→winter wheat−summer maize (WM→WM) and seven DCRs as follow: fallow→winter wheat−summer maize (F→WM); spring maize→winter wheat−summer maize (Ms→WM); winter wheat→winter wheat−summer maize (W→WM); sweet potato→winter wheat−summer maize (Psw→WM); spring peanut→winter wheat−summer maize (Pns→WM); winter wheat−summer peanut→winter wheat−summer maize (WPn→WM) and potato−silage maize→winter wheat−summer maize (PMl→WM). Our results indicated that DCRs significantly changed certain soil health indicators in 2016/2017 compared with the control, where F→WM rotation significantly decreased soil pH by 2.7%. The DCRs, especial Psw→WM and Pns→WM rotations showed a potential positive effect on soil health indicators at the end of the second year (2017/2018) compared with the control, where sweet potato increased soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP), urease activity (UA) and alkaline phosphatase activity (APA) in 2017/2018 by 5.1%, 5.3%, 13.8%, 9.4%, and 13.5%, respectively. With the spring peanut, TN, AP, and soil APA were increased by 2.1%, 13.2%, and 7.7%, respectively. Although fertilizer and irrigation input of DCRs were lower than the control, no significant decrease was observed on actual wheat yield as compared to the control (7.79 Mg/ha). The finding of this study highlights the value of DCRs, especially, Psw→WM and Pns→WM rotations over WM double-cropping in the NCP.
Показать больше [+] Меньше [-]Responses of Winter Wheat Yield to Drought in the North China Plain: Spatial–Temporal Patterns and Climatic Drivers Полный текст
2020
Jianhua Yang | Jianjun Wu | Leizhen Liu | Hongkui Zhou | Adu Gong | Xinyi Han | Wenhui Zhao
Responses of Winter Wheat Yield to Drought in the North China Plain: Spatial–Temporal Patterns and Climatic Drivers Полный текст
2020
Jianhua Yang | Jianjun Wu | Leizhen Liu | Hongkui Zhou | Adu Gong | Xinyi Han | Wenhui Zhao
Understanding the winter wheat yield responses to drought are the keys to minimizing drought-related winter wheat yield losses under climate change. The research goal of our study is to explore the response patterns of winter wheat yield to drought in the North China Plain (NCP) and then further to study which climatic factors drive the response patterns. For this purpose, winter wheat yield was simulated by the Environmental Policy Integrated Climate (EPIC) crop model. Drought was quantified by standardized precipitation evapotranspiration index (SPEI), and the contributions of the various climatic factors were evaluated using predictive discriminant analysis (PDA) method. The results showed that the responses of winter wheat yield to different time-scale droughts have obvious spatial differences from the north part to the south part in the NCP. Winter wheat yield is more sensitive to the medium (6–9 months) and long (9–12 months) time-scale droughts that occurred in the key growth periods (April and May). The different response patterns of winter wheat yield to the different time-scale droughts are mainly controlled by temperature and water balance (precipitation minus potential evapotranspiration) in winter in the NCP. Compared with the water balance, temperature plays a more important role in driving the response pattern characteristics. These findings can provide a reference on how to reduce drought influences on winter wheat yield in the NCP.
Показать больше [+] Меньше [-]Responses of Winter Wheat Yield to Drought in the North China Plain: Spatial–Temporal Patterns and Climatic Drivers Полный текст
2020
Yang, Jianhua | Wu, Jianjun | Liu, Leizhen | Zhou, Hongkui | Gong, Adu | Han, Xinyi | Zhao, Wenhui
Understanding the winter wheat yield responses to drought are the keys to minimizing drought-related winter wheat yield losses under climate change. The research goal of our study is to explore the response patterns of winter wheat yield to drought in the North China Plain (NCP) and then further to study which climatic factors drive the response patterns. For this purpose, winter wheat yield was simulated by the Environmental Policy Integrated Climate (EPIC) crop model. Drought was quantified by standardized precipitation evapotranspiration index (SPEI), and the contributions of the various climatic factors were evaluated using predictive discriminant analysis (PDA) method. The results showed that the responses of winter wheat yield to different time-scale droughts have obvious spatial differences from the north part to the south part in the NCP. Winter wheat yield is more sensitive to the medium (6–9 months) and long (9–12 months) time-scale droughts that occurred in the key growth periods (April and May). The different response patterns of winter wheat yield to the different time-scale droughts are mainly controlled by temperature and water balance (precipitation minus potential evapotranspiration) in winter in the NCP. Compared with the water balance, temperature plays a more important role in driving the response pattern characteristics. These findings can provide a reference on how to reduce drought influences on winter wheat yield in the NCP.
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