Bangyou Zheng

The Commonwealth Scientific and Industrial Research Organisation | CSIRO · Agriculture and Food

Extreme climate, especially temperature, can severely reduce wheat yield. As global warming has already begun to increase mean temperature and the occurrence of extreme temperatures, it has become urgent to accelerate the 5-20 year process of breeding for new wheat varieties, to adapt to future climate. We analyzed the patterns of frost and heat ev...

Plant breeding trials are extensive (100s to 1000s of plots) and are difficult and expensive to monitor by conventional means, especially where measurements are time-sensitive. For example, in a land-based measure of canopy temperature (hand-held infrared thermometer at two to 10 plots per minute), the atmospheric conditions may change greatly duri...

Heading time is a major determinant of the adaptation of wheat to different environments, and is critical in minimizing risks of frost, heat, and drought on reproductive development. Given that major developmental genes are known in wheat, a process-based model, APSIM, was modified to incorporate gene effects into estimation of heading time, while...

Radiant spring frosts occurring during reproductive developmental stages can result in catastrophic yield loss for wheat producers. To better understand the spatial and temporal variability of frost, the occurrence and impact of frost events on rain-fed wheat production was estimated across the Australian wheatbelt for 1957-2013 using a 0.05 ° grid...

Early vigour is an important physiological trait to improve establishment, water-use efficiency, and grain yield for wheat. Phenotyping large numbers of lines is challenging due to the fast growth and development of wheat seedlings. Here we developed a new photo-based workflow to monitor dynamically the growth and development of the wheat canopy of...

Precise and timely estimation of the glutelin-to-gliadin ratio (Glu/Gli) in wheat grain is pivotal for crop monitoring, as it is a crucial quality indicator ensuring the production of high-quality wheat flour. Despite the recognized potential of hyperspectral technology in crop phenotype estimation, its application to estimate Glu/Gli in wheat grai...

Aboveground biomass (AGB) of plants is an agroecological indicator that can be used to monitor crop growth status and quantify biomass carbon stock in agricultural ecosystems. Although satellite remote sensing data and crop models are widely employed to estimate AGB dynamics, their application in small-scale research plots is often constrained by t...

The agro-pastoral transitional zone (APTZ) in northern China is a typical ecologically vulnerable zone and a comprehensive geographical transitional zone. Its land use pattern has significant type diversity and spatial interlocking, which is always related to the play of ecological barrier functions and the sustainability of social-ecological syste...

Cotton (Gossypium hirsutum L.) is an economically important crop in China, and responses of cotton yield in different regions to separate and joint changes in natural and anthropogenic factors are the foundation for sustainable development under climate change; however, these remain uncertain. Here, we analyzed the spatiotemporal evolution and hete...

In intercropping systems, higher crops block direct radiation, resulting in inevitable shading on the lower crops. Cumulative shading capacity ( CSC ), defined as the amount of direct radiation shaded by higher crops during a growth period, affects the light interception and radiation use efficiency of crops. Previous studies investigated the light...

In the past few decades, the Oceania region has experienced a general trend of rising temperature, increased rainfall variability, declining rainfall in parts of Australia and New Zealand, and increased rainfall, particularly extreme events in other parts of the Oceanian region. These changes pose challenges to agriculture, forcing agricultural man...

It is valuable to develop a generic model that can accurately estimate the leaf area index (LAI) of wheat from unmanned aerial vehicle-based multispectral data for diverse soil backgrounds without any ground calibration. To achieve this objective, 2 strategies were investigated to improve our existing random forest regression (RFR) model, which was...

Introduction In wheat, kernel weight (KW) is a key determinant of grain yield (GY). However, it is often overlooked when improving wheat productivity under climate warming. Moreover, little is known about the complex effects of genetic and climatic factors on KW. Here, we explored the responses of wheat KW to diverse allelic combinations under proj...

Context Wheat (Triticum aestivum L.) adaptation is highly dependent on crop lifecycle duration, particularly the time at which flowering occurs in a specific environment. Frost, low solar radiation, heat and drought can significantly reduce yield if a crop flowers too early or late. Wheat genotypes have different lifecycle durations determined by p...

The relative time to maturity of grain crops is an important consideration for producers, yet there are no universally accepted classification schemes for cultivar phenology to guide decisions on variety selection and time of sowing. A first edition of an industry guide for wheat variety maturity was recently developed for use across Australia, rep...

Climate change poses complex impacts on the global wheat supply and demand chain. The impacts of climate change on average wheat yields are reasonably well studied, but its effects on yield variability and the associated economic consequences are poorly understood. Here, we show that future global wheat prices will exhibit steeper spikes at 2°C glo...

Winter wheat growth and development in Huaibei Plain, Anhui Province, China is often subjected to the spring cold spell (SCS), which causes significant yield losses when it occurs during spikelet and floret development. However, there is no quantitative information available to describe the characteristics of SCS occurrence. Thus, this study aims t...

High-throughput phenotyping has become the frontier to accelerate breeding through linking genetics to crop growth estimation, which requires accurate estimation of leaf area index (LAI). This study developed a hybrid method to train the random forest regression (RFR) models with synthetic datasets generated by a radiative transfer model to estimat...

A major challenge for the estimation of crop traits (biophysical variables) from canopy reflectance is the creation of a high-quality training dataset. To address this problem, this research investigated a conceptual framework by integrating a crop growth model with a radiative transfer model to introduce biological constraints in synthetic trainin...

Recent research advances in wheat have focused not only on increasing grain yields, but also on establishing higher grain quality. Wheat quality is primarily determined by the grain protein content (GPC) and composition, and both of these are affected by nitrogen (N) levels in the plant as it develops during the growing season. Hyperspectral remote...

Increasing grain number through fine-tuning duration of the late reproductive phase (LRP; terminal spikelet to anthesis) without altering anthesis time has been proposed as a genetic strategy to increase yield potential (YP) of wheat. Here we conducted a modelling analysis to evaluate the potential of fine-tuning LRP in raising YP in irrigated mega...

Flowering-date stability is crucial for global adaptability of wheat to sustain a high grain yield within broad temperature ranges; however, the response mechanism of such stability to climate change remains unclear. Here, we developed a multi-locus genotype based (MLG-based) ecophysiological model to predict wheat-flowering date that allowed for t...

Improving plant net photosynthetic rates and accelerating water-soluble carbohydrate accumulation play an important role in increasing the carbon sources for yield formation of wheat (Triticum aestivum L.). Understanding and quantify the contribution of these traits to grain yield can provide a pathway towards increasing the yield potential of whea...

Quantitative studies on the effects of growing season, genotype (including photoperiod genes and vernalization genes), and their interaction (GGI) on the anthesis date of winter wheat (Triticum aestivum L.) are helpful to provide a scientific reference for selecting or developing adaptive varieties in target environments. In this study, we collecte...

In plant breeding, unmanned aerial vehicles (UAVs) carrying multispectral cameras have demonstrated increasing utility for high-throughput phenotyping (HTP) to aid the interpretation of genotype and environment effects on morphological, biochemical, and physiological traits. A key constraint remains the reduced resolution and quality extracted from...

The Global Wheat Head Detection (GWHD) dataset was created in 2020 and has assembled 193,634 labelled wheat heads from 4700 RGB images acquired from various acquisition platforms and 7 countries/institutions. With an associated competition hosted in Kaggle, GWHD_2020 has successfully attracted attention from both the computer vision and agricultura...

Aboveground dry weight (AGDW) and leaf area index (LAI) are indicators of crop growth status and grain yield as affected by interactions of genotype, environment, and management. Unmanned aerial vehicle (UAV) based remote sensing provides cost-effective and non-destructive methods for the high-throughput phenotyping of crop traits (e.g., AGDW and L...

To maximise the grain yield of spring wheat, flowering needs to coincide with the optimal flowering period (OFP) by minimising frost and heat stress on reproductive development. This global study conducted a comprehensive modelling analysis of genotype, environment and management to identify the OFPs for sites in irrigated mega-environments (MEs) o...

Yield is a function of environmental quality and the sensitivity with which genotypes react to that. Environmental quality is characterized by meteorological data, soil and agronomic management, whereas genotypic sensitivity is embodied by combinations of physiological traits that determine the crop capture and partitioning of environmental resourc...

The Global Wheat Head Detection (GWHD) dataset was created in 2020 and has assembled 193,634 labelled wheat heads from 4,700 RGB images acquired from various acquisition platforms and 7 countries/institutions. With an associated competition hosted in Kaggle, GWHD has successfully attracted attention from both the computer vision and agricultural sc...

Ground coverage (GC) allows monitoring of crop growth and development and is normally estimated as the ratio of vegetation to the total pixels from nadir images captured by visible-spectrum (RGB) cameras. The accuracy of estimated GC can be significantly impacted by the effect of 'mixed pixels', which is related to the spatial resolution of the ima...

A major challenge for the estimation of crop traits (biophysical variables) from canopy reflectance is the creation of a high-quality training dataset. This can be addressed by using radiative transfer models (RTMs) to generate training dataset representing "real-world" data in situations with varying crop types and growth status as well as various...

China has successfully reduced particulate matter pollution, but ozone concentrations continually grow. Here, we employed a atmospheric chemistry-climate model and modified two crop models with considering the effects of diffuse fertilization and ozone, which were validated by multiple observations. Using the state-of-the-art modeling approach, we...

Plant architectural traits are important selection criteria in plant breeding that relate to photosynthetic efficiency and crop productivity. Conventional manual measures of architectural traits for large breeding trials are labour- and time-consuming. In this study, we proposed a new method to reconstruct three-dimensional (3D) canopy architectura...

Plant phenotypes are often descriptive, rather than predictive of crop performance. As a result, extensive testing is required in plant breeding programs to develop varieties aimed at performance in the target environments. Crop models can improve this testing regime by providing a predictive framework to (1) augment field phenotyping data and deri...

Northern China is the major grain-production region in the country. To adapt to climate change and ensure food security with a fixed area of arable land, utilizing a multiple cropping frequency each year is regarded as an efficient method of offsetting the projected negative yield impacts on staple crops. Given that climate warming prolongs the pot...

The detection of wheat heads in plant images is an important task for estimating pertinent wheat traits including head population density and head characteristics such as health, size, maturity stage, and the presence of awns. Several studies have developed methods for wheat head detection from high-resolution RGB imagery based on machine learning...

In Australian wheat (Triticum aestivum L.) production, optimizing wheat phenology is essential for yield potential and to avoid stress, especially around flowering. Breeding could be accelerated by identifying key loci and developing models to predict genotype flowering times under different pedoclimatic scenarios. Here, association genetics for he...

Detection of wheat heads is an important task allowing to estimate pertinent traits including head population density and head characteristics such as sanitary state, size, maturity stage and the presence of awns. Several studies developed methods for wheat head detection from high-resolution RGB imagery. They are based on computer vision and machi...

Reducing the number of tillers per plant using a tiller inhibition (tin) gene has been considered as an important trait for wheat production in dryland environments. We used a spatial analysis approach with a daily time‐step coupled radiation and transpiration efficiency model to simulate the impact of the reduced‐tillering trait on wheat yield und...

Climate risks pervade agriculture and generate major consequences on crop production. We do not know what the next season will be like, let alone the season 30 years hence. Yet farmers need to decide on genotype and management (G×M) combinations in advance of the season and in the face of this environment risk. Beyond that, breeders must target tra...

The GRDC national phenology initiative has been established to better predict flowering time of wheat and barley across the major cropping regions of Australia. A total of 64 wheat and 32 barley genotypes, selected for their diverse phenology, are being genotyped and phenotyped under different controlled conditions to parameterise the model. The sa...

Genotype by environment interaction (G×E) for the target trait, e.g. yield, is an emerging property of agricultural systems and results from the interplay between a hierarchy of secondary traits involving the capture and allocation of environmental resources during the growing season. This hierarchy of secondary traits ranges from basic traits that...

Genomic prediction of complex traits, say yield, benefits from including information on correlated component traits. Statistical criteria to decide which yield components to consider in the prediction model include the heritability of the component traits and their genetic correlation with yield. Not all component traits are easy to measure. Theref...

Crop water productivity has been receiving special attention in regards to productivity and food security. Limited-transpiration rate (LTR) at high vapour pressure deficit (VPD) has potential to improve drought adaptation. The quantification of the impact of LTR on water consumption, biomass accumulation and yield formation requires the use of dyna...

Image analysis using proximal sensors can help accelerate the selection process in plant breeding and improve the breeding efficiency. However, the accuracies of extracted phenotypic traits, especially those that require image classification, are affected by the pixel size in images. Ground coverage (GC), the ratio of projected to ground vegetation...

The yield of cereal crops such as sorghum (Sorghum bicolor L. Moench) depends on the distribution of crop-heads in varying branching arrangements. Therefore, counting the head number per unit area is critical for plant breeders to correlate with the genotypic variation in a specific breeding field. However, measuring such phenotypic traits manually...

In spite of the increasing expectation for process-based crop modelling to capture genotype (G) by environment (E) by management (M) interactions to support breeding selections, it remains a challenge to use current crop models to accurately predict phenotypes from genotypes or from candidate genes. We use wheat as a target crop and the APSIM farmi...

Background: Plant height is an important selection target since it is associated with yield potential, stability and particularly with lodging resistance in various environments. Rapid and cost-effective estimation of plant height from airborne devices using a digital surface model can be integrated with academic research and practical wheat breed...

Early vigour, or faster early leaf area development, has been considered an important trait for rainfed wheat in dryland regions such as Australia. However, early vigour is a genetically complex trait, and results from field experiments have been highly variable. Whether early vigour can lead to improved water use efficiency and crop yields is stro...

Continuous measurement of canopy temperature is an important indicator of plant water status of crops and the ability to predict canopy temperature will assist in the implementation of this technology for guiding crop irrigation scheduling. By noting that canopy temperature is related to its environmental weather variables which change over time of...

Multiple cropping systems have been widely used in China as smart strategies to address climate change to ensure that increasing food demand is met. In the context of climate warming, the climate-based boundaries of multiple cropping systems are moving northward, and the potential crop yield is projected to increase due to continuous cropping that...

Accurate prediction of the allocation and redistribution of crop biomass is essential for simulating the impact of crop traits and management approaches on field-scale outcomes. The Agricultural Production system Simulator (APSIM) Plant Modelling Framework (PMF) uses a generic ‘arbitration’ approach to allocate biomass among plant organs. Crop mode...

Phenotyping in breeding trials is the basis for the selection of new varieties of food, feed and fibre crops that support the continued growth of world population. In addition to economic yield, breeders measure many phenotypes (also called traits) associated with the adaptation of these crops, such as the time of flowering, the height of the crop...

Precision horticulture: Peachy method for monitoring orchard growth A rapid automated system for monitoring peach tree growth had been developed that could replace laborious field measurements and enable farmers to manage their orchards more effectively. Knowing a tree’s crown width—the mass of branches and foliage growing outwards from its trunk—e...

Showcases a framework for efficient counting of visually hard-to-detect and count crop (sorghum) - heads.

Sorghum (Sorghum bicolor L. Moench) is a C4 tropical grass that plays an essential role in providing nutrition to humans and livestock, particularly in marginal rainfall environments. The timing of head development and the number of heads per unit area are key adaptation traits to consider in agronomy and breeding but are time consuming and labor i...

El Niño–Southern Oscillation strongly influences rainfall and temperature patterns in Eastern Australia, with major impacts on frost, heat, and drought stresses, and potential consequences for wheat production. Wheat phenology is a key factor to adapt to the risk of frost, heat, and drought stresses in the Australian wheatbelt. This study explores...

Fractional vegetation coverage (FVC) is an important indicator to assess ecological environments and vegetation growing. It is also an important parameter in many land surface and ecological models. It is generally estimated by satellite-based remote sensing and ground investigation. However, it is challenging to precisely estimate the FVC of woody...

From 1990, the Agricultural Production Systems sIMulator (APSIM) has grown from a field-focused farming systems framework used by a small number of people, into a large collection of models used by thousands of modellers internationally. The software grew to consist of several hundred thousand lines of code in multiple programming languages. This h...

Breeding for improved reproductive frost tolerance could allow greater yield and economic benefits to be achieved by (i) reducing direct frost damage and (ii) allowing earlier sowing to reduce risks of late-season drought and/or heat stresses. We integrated APSIM-Wheat simulations with economic modelling to evaluate economic benefits of virtual gen...