To explore the feasibility of using UAV-LiDAR for measuring the leaf area index (LAI) of crop canopies, we employed UAV-LiDAR to scan sugarcane canopies during the tillering and elongation stages, acquiring canopy point cloud data. Subsequently, features such as average row height, projected row area, point cloud density at different canopy layers, and the ratios between these parameters were extracted. Three feature selection methods-partial least squares regression (PLSR), XGBoost feature importance (XGBoost-FI), and random forest-recursive feature elimination (RF-RFE)-were adopted to evaluate and identify the optimal input variables for modeling. With these selected variables, LAI inversion models were developed based on random forest (RF) and adaptive boosting (AdaBoost) algorithms, and their performance was assessed. Among the extracted features, the projected row area S_p and the total row point count C_total exhibited strong correlations with LAI, with correlation coefficients of 0.73 and 0.72, respectively. The AdaBoost-based LAI inversion model, using the projected row area S_p, average height H_avg, mid-layer point cloud density C_m, and total row point count C_total as input variables, achieved the best performance, with a coefficient of determination (R_v²) of 0.713 and a root mean square error (RMSE_v) of 0.25 on the validation set. This study provides an effective method for high-throughput acquisition of LAI in field crops, offering valuable scientific support for sugarcane field management and breeding efforts.
Plant Leaves/growth & development* ; Saccharum/growth & development* ; Algorithms ; Unmanned Aerial Devices ; Remote Sensing Technology/methods* ; Crops, Agricultural/growth & development*

Accurately obtaining the crop quantity and density is not only crucial for the demand-based input of water and fertilizer in the field but also vital for ensuring the yield and quality of crops. Aerial photography by unmanned aerial vehicles (UAVs) can quickly acquire the distribution image information of crops over a large area. However, the accurate recognition of a single type of dense targets is a huge challenge for most recognition algorithms. Taking banana seedlings as an example in this study, we captured the images of banana plantations by UAVs from high altitudes to explore an efficient recognition method for dense targets. We proposed a strategy of "cut-recognition-stitch" and constructed a counting method based on the improved Faster R-CNN algorithm. First, the images containing highly dense targets were cropped into a large number of image tiles according to different sizes (simulating different flight altitudes), and the Contrast Limited Adaptive Histogram Equalization (CLAHE) algorithm was adopted to improve the image quality. A banana seedling dataset containing 36 000 image tiles was constructed. Then, the Faster R-CNN network with optimized parameters was used to train the banana seedling recognition model. Finally, the recognition results were reversely stitched together, and a boundary deduplication algorithm was designed to correct the final counting results to reduce the repeated recognition caused by image cropping. The results show that the recognition accuracy of the Faster R-CNN with optimized parameters for banana image datasets of different sizes can reach up to 0.99 at most. The deduplication algorithm can reduce the average counting error for the original aerial images from 1.60% to 0.60%, and the average counting accuracy of banana seedlings reaches 99.4%. The proposed method effectively addresses the challenge of recognizing dense small objects in high-resolution aerial images, providing an efficient and reliable technical solution for intelligent crop density monitoring in precision agriculture.
Musa/growth & development* ; Crops, Agricultural/growth & development* ; Algorithms ; Neural Networks, Computer ; Unmanned Aerial Devices ; Seedlings/growth & development* ; Image Processing, Computer-Assisted/methods* ; Photography ; Agriculture/methods*

Genetically modified (GM) crops, as a pivotal innovation in modern agriculture, exhibit significant advantages such as pest and disease resistance, herbicide tolerance, stress tolerance, and yield enhancement. However, their widespread adoption has been associated with potential ecological risks, including weediness of transgenic plants, gene flow, emergence of novel viral strains in virus-resistant crops, impacts on non-target organisms and soil ecosystems, and evolution of target pest resistance. This review focuses on the dual characteristics of GM crops, systematically examining their agronomic benefits and the underlying mechanisms of ecological risks. This review provides a theoretical foundation for optimizing the development of GM crops and ecological risk management, facilitating sustainable agricultural practices.
Plants, Genetically Modified/growth & development* ; Crops, Agricultural/growth & development* ; Ecosystem ; Ecology

Domestic rice (Oryza sativa L.) is one of the most important cereal crops, feeding a large number of worldwide populations. Along with various high-throughput genome sequencing projects, rice genomics has been making great headway toward direct field applications of basic research advances in understanding the molecular mechanisms of agronomical traits and utilizing diverse germplasm resources. Here, we briefly review its achievements over the past two decades and present the potential for its bright future.
Crops, Agricultural ; genetics ; Genome, Plant ; genetics ; Genomics ; High-Throughput Nucleotide Sequencing ; Oryza ; genetics ; growth & development ; Phenotype

Plant height is one of the most important agronomic traits that could affect both crop yield and quality. Among all the hormones, gibberellins are crucial to regulate plant height. Cloning and molecular mechanism research of the plant height genes associated gibberellins have extremely important value for the regulation of crop growth and agricultural production, and have been widely used in rice, wheat and other grain crops breeding. In order to promote utilization of gibberellins in fruit trees, flowers and other horticultural crops breeding, we reviewed the regulation of plant height by gibberellins biosynthesis and signal transduction at the molecular level in this paper.
Crops, Agricultural ; genetics ; growth & development ; Flowers ; growth & development ; Fruit ; growth & development ; Gene Expression Regulation, Plant ; Genes, Plant ; genetics ; Gibberellins ; biosynthesis ; pharmacology ; Plant Growth Regulators ; biosynthesis ; pharmacology ; Plant Stems ; growth & development ; Signal Transduction ; Trees ; genetics ; growth & development

OBJECTIVETo explore the solution of continuous cropping obstacle of Panax notoginseng.

METHODThe effects of balanced fertilization and soil amendment on the emergence rate, survival rate, growth and yield of P. notoginseng were studied with a pot culture experiment in 3-year-interval continuous cropping soil.

RESULTThe result showed that the content of total N, total P, available N, available P and other available components in continuous cropping soil were higher than those in fresh soil while available K and the rate of K/N were declined, and available Cu and some other micro elements were lack. The way of balanced fertilization "low N + fused calcium-magnesium-phosphate fertilizer + high K + lime + micro elements" would significantly enhance the rate of survival, biomass and yield. It also promoted the growth of P. notoginseng in continuous cropping. The bagasse could relieve the continuous cropping obstacle obviously, the survival rate was improved for 31.6% and the yield of medicinal materials was 19.5%. The fly ash had also some effect in relieving the continuous cropping obstacle.

CONCLUSIONThe overall results suggested that the adequate fertilization plan is the applying lime, reducing N, applying calcium-magnesium-phosphate fertilizer, improving K and supplying mircoelement as well as applying bagasse to resolve the problem of continuous cropping obstacle of P. notoginseng.

Biomass ; Crops, Agricultural ; growth & development ; metabolism ; physiology ; Fertilization ; Nitrogen ; Panax notoginseng ; growth & development ; metabolism ; physiology ; Phosphates ; Soil ; chemistry

OBJECTIVETo explore effects on allelopathic autotoxicity of Rehmannia glutinosa of different abatement measures.

METHODThe experiments for abating allelopathic effects of R. glutinosa were designed with the reducing rate as a indication, three measures of the treating soil with lime nitrogen, and water washing were employed, R. glutinosa- Achyranthes bidentata rotation system and using Achyranthes bidentata as green manure, and seedling transplant were also studied for the abatement effect.

RESULTEffect of seedling transplant was the best, reducing rate of transplant and bare root transplant on the 20th day after emergence was 76.80%, 71.70%, respectively. The reducing rate of the treating soil with microorganism reached 54.25%. The effects of water washing and R. glutinosa-A. bidentata rotation system and using A. bidentata as green manure were not satisfied. Especially only using A. bidentata as green manure without rotation system worsened the allelopathic effects of R. glutinosa.

CONCLUSIONAll measures can abate allelopathic effects of R. glutinosa to some extent except only using A. bidentata as green manure.

Crops, Agricultural ; Rehmannia ; growth & development ; toxicity ; Seedlings ; physiology ; Soil Microbiology

A workshop on "Chips, Computers and Crops" was held in Hangzhou, China during September 26-27, 2008. The main objective of the workshop was to bring together China and UK scientists from mathematics, bioinformatics and plant molecular biology communities to exchange ideas, enhance awareness of each others' fields, explore synergisms and make recommendations on fruitful future directions in crop science. Here we describe the contributions to the workshop, and examine some conceptual issues that lie at the foundations and future of crop systems biology.
China ; Computational Biology ; methods ; Crops, Agricultural ; genetics ; growth & development ; Genome, Plant ; Humans ; International Cooperation ; Mathematical Computing ; Molecular Biology ; methods ; United Kingdom

OBJECTIVETo study optimum planting density and sowing depth of Tulipa edulis.

METHODThe effects of different planting densities, sowing depth and thin plastic film cover were studied on yield, rate of increase, bulb weight increased multiples, and proliferation rate of bulb.

RESULT AND CONCLUSIONUnder 30-200 bulbs per squremeter density range, the yield increased with the density increasing, and reached significance level. In 5-20 centimeter depth range, the yield and the number of harvested bulbs enhanced along with the sowing depth increasing, and the best sowing depth was 20 cm. Thin plastic film cover showed no effect on the growth.

Agriculture ; methods ; Crops, Agricultural ; growth & development ; Tulipa ; growth & development

OBJECTIVETo investigate the effects of top pruning on fruiting characters of Platycodon grandiflorum, and find the suitable stage, in which seed growth and development furtherly.

METHODOne-year old seedlings were chosen and planted in field. Plant height, branching number, fruit number per plant, 1000 grains weight were measured during growth and development period, respectively.

RESULTThe treatment of top pruning postponed in turn the flowering date, lowered the plant heights and the fruit number per plant, increased the branching number and influenced significantly on 1000 grains weights.

CONCLUSIONThe suitable stage of top pruning for producing seeds was from June 20th to July 5th.

Crops, Agricultural ; growth & development ; Fruit ; growth & development ; Platycodon ; growth & development