Intelligence has been considered as the major challenge in promoting economic potential and production efficiency of precision agriculture. In order to apply advanced deep-learning technology to complete various agricultural tasks in online and offline ways, a large number of crop vision datasets with domain-specific annotation are urgently needed. To encourage further progress in challenging realistic agricultural conditions, we present the CropDeep species classification and detection dataset, consisting of 31,147 images with over 49,000 annotated instances from 31 different classes. In contrast to existing vision datasets, images were collected with different cameras and equipment in greenhouses, captured in a wide variety of situations. It features visually similar species and periodic changes with more representative annotations, which have supported a stronger benchmark for deep-learning-based classification and detection. To further verify the application prospect, we provide extensive baseline experiments using state-of-the-art deep-learning classification and detection models. Results show that current deep-learning-based methods achieve well performance in classification accuracy over 99%. While current deep-learning methods achieve only 92% detection accuracy, illustrating the difficulty of the dataset and improvement room of state-of-the-art deep-learning models when applied to crops production and management. Specifically, we suggest that the YOLOv3 network has good potential application in agricultural detection tasks.

CropDeep: The Crop Vision Dataset for Deep-Learning-Based Classification and Detection in Precision Agriculture.

https://ris.utwente.nl/ws/files/70061104/waterscarcity.pdf

Water scarcity alleviation through water footprint reduction in agriculture: The effect of soil mulching and drip irrigation

Raising temperature and increased drought events induced by a changing climate have increased the need for efficient use of natural resources and energy supplies. Producing sufficient food and fibers for the growing population with changing consumption patterns from ever decreasing resource base requires strategic plans for efficient use of natural resources such as water, nutrients, and photosynthetically active radiation (PAR). Water is considered as the second most limiting factor after land to increase food and fiber production. It is essential for various chemical and physiological reactions in plants and provides a medium where most cellular functions take place. Soil water-deficit significantly reduces crop yield and productivity through its adverse effects on nutrient uptake, net assimilation, and radiation use efficiency and subsequently on dry matter accumulation and production. Soil water affects nutrient transformation from unavailable to available form or vice versa, and thereby the total uptake amount. It also influences the availability of applied nutrients and efficiency through its effect on various nutrient loss mechanisms such as volatilization, nitrification, and/or urease hydrolysis. Soil nutrients and PAR are also key factors in crop production. Plants usually suffer from nutrient deficiencies and more importantly a reduction in net photosynthetic assimilation rate under water stress. Better inception of PAR is needed for higher biomass production and grain yield, which is also hampered under water-limited environments. The situation is expected to be further intensified in a future changing climate, which urgently calls for efficient adaptation strategies to mitigate the negative impacts associated with these changes on crop production, especially in dry areas. Therefore, improving the efficiency of natural resources use continues to escalate as a topic of interest for crop and soil scientists. This review presents an outline of defining water use efficiency, nitrogen use efficiency, and radiation use efficiency as well as their relationship under water-limited environments to identify agronomic- and physiologically-improved strategies for enhancing water, nutrient (nitrogen), and radiation use by field crops.

Improving water use efficiency, nitrogen use efficiency, and radiation use efficiency in field crops under drought stress: A review

Area under vegetable cultivation is expanding in arid and semi-arid regions of the world to meet the nutritional requirements of an ever-growing population. However, water scarcity in these areas is limiting vegetable productivity. New water-conserving irrigation management practices are being implemented in these areas. Under these irrigation management practices, crops are frequently exposed to some extent of water stress. Vegetables are highly sensitive to water stress. For the successful implementation of new irrigation practices in vegetable crops, it is of immense importance to determine the threshold water deficit level which will not have a detrimental effect on plant growth and yield. Along with this, plant response and adaptation mechanisms to new irrigation practices need to be understood for the successful implementation of new irrigation practices. To understand this, water stress indicators that are highly responsive to water stress; and that can help in early detection of water stress need to be identified for vegetable crops. Plant-based water stress indicators are quite effective in determining the water stress level in plants because they take into account the cumulative effect of water stress due to declining soil moisture status and increased evaporative demand of the atmosphere while determining the water stress level in plant. Water stress quantification using plant-based approaches involves direct measurements of several aspects of plant water status and indirect measurements of plant processes which are highly sensitive to water deficit. In this article, a number of plant-based water stress indicators were critically reviewed for (1) their efficacy to determine the level of water stress, (2) their potential to predict the yield of a crop as affected by different water-deficit levels and (3) their suitability for irrigation scheduling in vegetable crops.

A Review on Potential Plant-Based Water Stress Indicators for Vegetable Crops

Coffee is one of the most important global crops and provides a livelihood to millions of people living in developing countries. Coffee species have been described as being highly sensitive to climate change, as largely deduced from modeling studies based on predictions of rising temperatures and changing rainfall patterns. Here, we discuss the physiological responses of the coffee tree in the context of present and ongoing climate changes, including drought, heat, and light stresses, and interactions between these factors. We also summarize recent insights on the physiological and agronomic performance of coffee at elevated atmospheric CO2 concentrations and highlight the key role of CO2 in mitigating the harmful effects of heat stress. Evidence is shown suggesting that warming, per se, may be less harmful to coffee suitability than previously estimated, at least under the conditions of an adequate water supply. Finally, we discuss several mitigation strategies to improve crop performance in a changing w...

Physiological and Agronomic Performance of the Coffee Crop in the Context of Climate Change and Global Warming: A Review.

Agriculture consumes more than two thirds of the total freshwater of the planet. This issue causes substantial conflict in freshwater allocation between agriculture and other economic sectors. Regulated deficit irrigation (RDI) is key technology because it helps to improve water use efficiency. Nonetheless, there is a lack of understanding of the mechanisms with which plants respond to RDI. In particular, little is known about how RDI might increase crop production while reducing the amount of irrigation water in real-world agriculture. In this review, we found that RDI is largely implemented through three approaches: (1) growth stage-based deficit irrigation, (2) partial root-zone irrigation, and (3) subsurface dripper irrigation. Among these, partial root-zone irrigation is the most popular and effective because many field crops and some woody crops can save irrigation water up to 20 to 30 % without or with a minimal impact on crop yield. Improved water use efficiency with RDI is mainly due to the following: (1) enhanced guard cell signal transduction network that decreases transpiration water loss, (2) optimized stomatal control that improves the photosynthesis to transpiration ratio, and (3) decreased evaporative surface areas with partial root-zone irrigation that reduces soil evaporation. The mechanisms involved in the plant response to RDI-induced water stress include the morphological traits, e.g., increased root to shoot ratio and improved nutrient uptake and recovery; physiological traits, e.g., stomatal closure, decreased leaf respiration, and maintained photosynthesis; and biochemical traits, e.g., increased signaling molecules and enhanced antioxidation enzymatic activity.

/pdf/regulated-deficit-irrigation-for-crop-production-under-56r07mng0s.pdf

Hui-Lian Xu

Papers

Regulated deficit irrigation for crop production under drought stress. A review