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This review emphasizes the significance of combining regulated deficit irrigation (RDI) with woody crops, as they have higher water productivity (WP) and are tolerant to mild water deficits. After conducting the analysis, it was found that for most woody crops, reducing irrigation water by 20.0–30.0% has a negligible impact on yield, typically within a variation range of 10.0%, and it leads to an increase in WP of 10.0–30.0%. When irrigation water is reduced by 40.0–50.0%, the impact on yield varies significantly depending on the species, but the WP generally approaches its highest value; in general, it can increase by 25.0% or more and sometimes even exceed 50.0%. However, when irrigation water is further reduced, it significantly affects yield, and there is a limited increase or even decrease in WP. Moreover, adjusting irrigation amounts during noncritical water demand periods minimizes the impact on yield and fruit size, enhancing water-saving effectiveness. Water-saving techniques trigger various plant responses, improving resistance to water deficits, promoting reproductive growth, and protecting against drought-related damage. Despite potential yield reductions, ongoing research demonstrates positive outcomes in WP, crop yield, and fruit quality in various woody crops. Water-saving techniques offer economic benefits through cost savings and pest reduction, while finding the appropriate balance between water use, yield, and quality is vital for agricultural success and sustainable water resource management. Moreover, water-saving techniques optimize nutrient uptake and heavy metal absorption in woody crop agricultural systems, addressing heavy metal stress, soil salinization, and emissions. Combining multiple irrigation methods, such as partial root-zone drying (PRD), shows immense potential in water conservation and impact on fruits. Integrating PRD with innovative techniques, such as precision irrigation or sensor-based systems, promises remarkable water savings and optimized crop yields, revolutionizing agricultural practices and addressing water scarcity challenges for sustainable irrigation management.

The quality of oranges is grounded on their appearance and diameter. Appearance refers to the skin’s smoothness and surface cleanliness; diameter refers to the transverse diameter size. They are visual attributes that visual perception technologies can automatically identify. Nonetheless, the current orange quality assessment needs to address two issues: 1) There are no image datasets for orange quality grading; 2) It is challenging to effectively learn the fine-grained and distinct visual semantics of oranges from diverse angles. This study collected 12 522 images from 2 087 oranges for multi-grained grading tasks. In addition, it presented a visual learning graph convolution approach for multi-grained orange quality grading, including a backbone network and a graph convolutional network (GCN). The backbone network’s object detection, data augmentation, and feature extraction can remove extraneous visual information. GCN was utilized to learn the topological semantics of orange feature maps. Finally, evaluation results proved that the recognition accuracy of diameter size, appearance, and fine-grained orange quality were 99.50, 97.27, and 97.99%, respectively, indicating that the proposed approach is superior to others.

Coleorhiza hairs are hairlike structures in seeds of the grass family (Poaceae). The molecular mechanisms underlying its formation are largely unknown, study on this topic will expand our understanding of the effects of water status on germination during rice (Oryza sativa L.) direct seeding. Seeds of Nipponbare were treated under two water conditions: in one, half of the seed surface was immersed in water and the other half was embryo side in air (EIA), and in the other, the whole seed was covered by water (CBW). Coleorhiza hairs formed only in EIA samples. Transcriptomics was used to identify the gene regulation during coleorhiza hair formation in EIA (vs. CBW) embryos and endosperm. Embryos displayed more transcriptome modulation even though smaller in size than the endosperm. Differentially expressed genes (DEGs) were enriched in both primary and secondary metabolism and showed changes in abscisic acid, auxin, jasmonic acid, and salicylic acid signatures. Metabolites enrichment data were positively correlated with gene expression changes in the affected metabolic functional pathways. The presence of shorter coleorhiza hairs in an OsRHL1 (Os06g0184000, a coleorhiza hair formation regulation candidate gene) knockout mutant suggested that root hair-associated DEGs share molecular regulators that control the formation of coleorhiza hairs.

In order to improve the image segmentation performance of cotton leaves in natural environment, an automatic segmentation model of diseased leaf with active gradient and local information is proposed. Firstly, a segmented monotone decreasing edge composite function is proposed to accelerate the evolution of the level set curve in the gradient smooth region. Secondly, canny edge detection operator gradient is introduced into the model as the global information. In the process of the evolution of the level set function, the guidance information of the energy function is used to guide the curve evolution according to the local information of the image, and the smooth contour curve is obtained. And the main direction of the evolution of the level set curve is controlled according to the global gradient information, which effectively overcomes the local minima in the process of the evolution of the level set function. Finally, the Heaviside function is introduced into the energy function to smooth the contours of the motion and to increase the penalty function φ(x) to calibrate the deviation of the level set function so that the level set is smooth and closed. The results showed that the model of cotton leaf edge profile curve could be obtained in the model of cotton leaf covered by bare soil, straw mulching and plastic film mulching, and the ideal edge of the ROI could be realized when the light was not uniform. In the complex background, the model can segment the leaves of the cotton with uneven illumination, shadow and weed background, and it is better to realize the ideal extraction of the edge of the blade. Compared with the Geodesic Active Contour (GAC) algorithm, Chan-Vese (C-V) algorithm and Local Binary Fitting (LBF) algorithm, it is found that the model has the advantages of segmentation accuracy and running time when processing seven kinds of cotton disease leaves images, including uneven lighting, leaf disease spot blur, adhesive diseased leaf, shadow, complex background, unclear diseased leaf edges, and staggered condition. This model can not only conduct image segmentation of cotton leaves under natural conditions, but also provide technical support for the accurate identification and diagnosis of cotton diseases.

It is generally known that the culture for mycoplasma is time-consuming and a variety of nutrients are needed in the culture medium. This brings a lot of difficulties to mycoplasma research and application, including Mycoplasma mycoides subsp. capri (Mmc). Furthermore, little research on the characteristics of Mmc metabolism has been reported. In this study, Mmc PG3 strain cultures were investigated for dynamic gene expression. Culture samples were harvested during logarithmic phase (PG3-1), stationary phase (PG3-2), decline phase (PG3-3) and late decline phase (PG3-4). Twelve RNA samples (three replicates for each of the four growth stages considered) from these cultures were collected and sequenced. Paired comparison between consecutive growth phases in the four growth stages showed 45 significant differentially expressed genes (P

This study investigated if super rice could better cope with soil water deficit and if it could have better yield performance and water use efficiency (WUE) under alternate wetting and drying (AWD) irrigation than check rice. Two super rice cultivars and two elite check rice cultivars were grown in pots with three soil moisture levels, well watered (WW), moderate water deficit (MWD) and severe water deficit (SWD). Two cultivars, each for super rice and check rice, were grown in field with three irrigation regimes, alternate wetting and moderate drying (AWMD), alternate wetting and severe drying (AWSD) and conventional irrigation (CI). Compared with that under WW, grain yield was significantly decreased under MWD and SWD treatments, with less reduction for super rice than for check rice. Super rice had higher percentage of productive tillers, deeper root distribution, higher root oxidation activity, and greater aboveground biomass production at mid and late growth stages than check rice, especially under WMD and WSD. Compared with CI, AWMD increased, whereas AWSD decreased grain yield, with more increase or less decrease for super rice than for check rice. Both MWD and SWD treatments and either AWMD or AWSD regime significantly increased WUE compared with WW treatment or CI regime, with more increase for super rice than for check rice. The results suggest that super rice has a stronger ability to cope with soil water deficit and holds greater promising to increase both grain yield and WUE by adoption of moderate AWD irrigation.

Selection of quantitative characteristics, division of their expression ranges, and selection of example varieties are key issues on developing DUS Test Guidelines, which are more crucial for quantitative characteristics since their expressions vary in different degrees. Taking the development of DUS Test Guideline of Ranunculus asiaticus L. as an example, this paper applied statistic-based approaches for the analyses of quantitative characteristics. We selected 9 quantitative characteristics from 18 pre-selected characteristics, based on within-variety uniformity, stability between different growing cycles, and correlation among characteristics, by the analyses of coefficient of variation, paired-samples t-test and partial correlation. The expression ranges of the 9 selected quantitative characteristics were divided into different states using descriptive statistics and distribution frequency of varieties. Eight of the 9 selected quantitative characteristics were categorized as standard characteristics as they showed one peak in distribution frequency of 120 varieties in various expressions of the characteristics, whereas, plant height can be categorized as grouping characteristic since it gave two peaks, and can group the varieties into pot and cut varieties. Finally, box-plot was applied to visually select the example varieties, and varieties 7, 12, and 28 were determined as the example varieties for plant height. The methods described in this paper are effective for the selection of quantitative characteristics, division of expression ranges, and selection of example varieties in Ranunculus asiaticus L. for DUS test, and may also be interest for other plant genera.

Field experiments were conducted for two years to investigate the benefits of alternate furrow irrigation on fruit yield, quality and water use efficiency of grape (Vitis vinifera L. cv. Rizamat) in the arid region of Northwest China. Two irrigation treatments were included, i.e., conventional furrow irrigation (CFI, two root-zones were simultaneously irrigated during the consecutive irrigation) and alternate partial root-zone furrow irrigation (AFI, two root-zones were alternatively irrigated during the consecutive irrigation). Results indicate that AFI maintained similar photosynthetic rate (Pn) but with a reduced transpiration rate when compared to CFI. As a consequence, AFI improved water use efficiency based on evapotranspiration (WUEET, fruit yield over water consumed) and irrigation (WUEI, fruit yield over water irrigated) by 30.0 and 34.5%, respectively in 2005, and by 12.7 and 17.7%, respectively in 2006. AFI also increased the edible percentage of berry by 2.91–4.79% significantly in both years. Vitamin C (Vc) content content of berry was increased by 25.6–37.5%, and tritrated acidity (TA) was reduced by 9.5–18.1% in AFI. This resulted in an increased total soluble solid content (TSS) to TA ratio (TSS/TA) by 11.5–16.7% when compared to CFI in both years. Our results indicate that alternate furrow irrigation is a practical way to improve grape fruit quality and water use efficiency for irrigated crops in arid areas.

Stalk related traits, comprising plant height (PH), ear height (EH), internode number (IN), average internode length (AIL), stalk diameter (SD), and ear height coefficient (EHC), are significantly correlated with yield, density tolerance, and lodging resistance in maize. To investigate the genetic basis for stalk related traits, a doubled haploid (DH) population derived from a cross between NX531 and NX110 were evauluated under two densities over 2 yr. The additive quantitative trait loci (QTLs), epistatic QTLs were detected using inclusive composite interval mapping and QTL-by-environment interaction were detected using mixed linear model. Differences between the two densities were significant for the six traits in the DH population. A linkage map that covered 1 721.19 cM with an average interval of 10.50 cM was constructed with 164 simple sequence repeat (SSR). Two, two, seven, six, two, and eight additive QTLs for PH, IN, AIL, EH, SD, and EHC, respectively. The extend of their contribution to penotypic variation ranged from 10.10 to 31.93%. Seven QTLs were indentified simultaneously under both densities. One pair, two pairs and one pair of epistatic effects were detected for AIL, SD and EHC, respectively. No epistatic effects were detected for PH, EH, and IN. Nineteen QTLs with environment interactions were detected and their contribution to phenotypic variation ranged from 0.43 to 1.89%. Some QTLs were stably detected under different environments or genetic backgrounds comparing with previous studies. These QTLs could be useful for genetic improvement of stalk related traits in maize breeding.

Knowledge on the performance in grain yield and physiological traits is essential to understand the main yield-limiting factor and make strategies for breeding and crop management in rice (Oryza sativa L.). This study investigated the changes in grain yield and associated physiological traits of rice in the Yangtze River Basin of China during the last 60 yr. Thirteen mid-season indica and 12 japonica rice cultivars that were popularly used were grown in the field in 2008 and 2009. The grain yield and yield components, biomass, leaf area, leaf photosynthesis, root oxidation activity, and harvest index were examined. The results showed that grain yield and grain yield per day have progressively increased during the years and such increases are mainly attributed to the expanded sink size as a result of more spikelets per panicle, especially for the case of super rice. Both biomass and harvest index were increased with the improvement of cultivars. Increase in biomass for modern rice cultivars was associated with an enhancement of leaf area and photosynthesis, root dry weight, and root oxidation activity, although the indica super rice cultivars showed a lower leaf photosynthetic rate and root oxidation activity than the semi-dwarf cultivars during the grain filling period. Both indica and japonica super rice cultivars exhibited a low percentage of filled grains, which may limit their great yield potential. All the data suggested that grain yield have been substantially improved during the 60 yr of rice breeding in the Yangtze River Basin. Expanded sink size, increased dry matter production and harvest index, and enhanced leaf area and photosynthesis, root dry weight, and root oxidation activity contribute to the improvement in grain yield. Increase in filling efficiency could realize the great yield potential in super rice.

Root system is a vital part of plant and regulates many aspects of shoot growth and development. This paper reviews how some traits of root morphology and physiology are related to the formation of grain yield in rice (Oryza sativa L.). Higher root biomass, root oxidation activity, and cytokinin contents in roots are required for achieving more panicle number, more spikelets per panicle, greater grain-filling percentage, and higher grain yield. However, these root traits are not linearly correlated with yield components. When these traits reach very high levels, grain filling and grain yield are not necessarily enhanced. High numbers of mitochondria, Golgi bodies, and amyloplasts in root tip cells benefit root and shoot growth and yield formation. Proper crop management, such as an alternate wetting and moderate soil drying irrigation, can significantly improve ultra-structure of root tip cells, increase root length density and concentration of cytokinins in root bleedings, and consequently, increase grain-filling percentage, grain yield, and water use efficiency. Further studies are needed to investigate the mechanism underlying root-shoot and root-soil interactions for high grain yield, the roles of root-sourced hormones in regulating crop growth and development and the effects of soil moisture and nutrient management on the root architecture and physiology.