Rapeseed (Brassica napus L.) is the second most widely grown premium oilseed crop globally, mainly for its vegetable oil and protein meal.  One of the main goals of breeders is producing high-yield rapeseed cultivars with sustainable production to meet the requirements of the fast-growing population.  Besides the pod number, seeds per silique (SS), and thousand-seed weight (TSW), the ovule number (ON) is a decisive yield determining factor of individual plants and the final seed yield.  In recent years, tremendous efforts have been made to dissect the genetic and molecular basis of these complex traits, but relatively few genes or loci controlling these traits have been reported thus far.  This review highlights the updated information on the hormonal and molecular basis of ON and development in model plants (Arabidopsis thaliana).  It also presents what is known about the hormonal, molecular, and genetic mechanism of ovule development and number, and bridges our understanding between the model plant species (A. thaliana) and cultivated species (B. napus).  This report will open new pathways for primary and applied research in plant biology and benefit rapeseed breeding programs.  This synopsis will stimulate research interest to further understand ovule number determination, its role in yield improvement, and its possible utilization in breeding programs. 

Leaves are the main places for photosynthesis and organic synthesis of cotton.  Leaf shape has important effects on the photosynthetic efficiency and canopy formation, thereby affecting cotton yield.  Previous studies have shown that LMI1 is the main gene regulating leaf shape. In this study, the LMI1 gene (LATE MERISTEM IDENTITY1) was inserted into the 35S promoter expression vector, and cotton plants overexpressing LMI1(OE) were obtained through genetical transformation.  Statistical analysis of the biological traits of T₁ and T₂ populations showed that compared to wild type (WT), OE plants had significant larger leaves, thicker stems and significantly increased dry weight.  Furthermore, plant sections of the main vein and petiole showed that the number of cell in those tissues of OE plants increased significantly.  In addition, RNA-seq analysis revealed differential expression of genes related to gibberellin synthesis and NAC gene family (genes containing the NAC domain) in OE and WT plants, suggesting that LMI1 is involved in secondary wall formation and cell proliferation, and promotes stem thickening.  Moreover, GO (Gene Ontology) analysis enriched the terms of calcium ion binding, and KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis enriched the terms of fatty acid degradation, phosphatidylinositol signal transduction system, and cAMP signal pathway.  These results suggested that LMI1 OE plants were responsive to gibberellin hormone signals, and altered messenger signal (cAMP, Ca²⁺) which amplified this function, to promote the stronger above ground vegetative growth.  This study found the LMI1 soared the nutrient growth in cotton, which is the basic for higher yield.

Banana is a significant crop, and three banana leaf diseases, including Sigatoka, Cordana and Pestalotiopsis, have the potential to have a serious impact on banana production. Existing studies are insufficient to provide a reliable method for accurately identifying banana leaf diseases. Therefore, this paper proposes a novel method to identify banana leaf diseases. First, a new algorithm called K-scale VisuShrink algorithm (KVA) is proposed to denoise banana leaf images. The proposed algorithm introduces a new decomposition scale k based on the semi-soft and middle course thresholds, the ideal threshold solution is obtained and substituted with the newly established threshold function to obtain a less noisy banana leaf image. Then, this paper proposes a novel network for image identification called Ghost ResNeSt-Attention RReLU-Swish Net (GR-ARNet) based on Resnet50. In this, the Ghost Module is implemented to improve the network's effectiveness in extracting deep feature information on banana leaf diseases and the identification speed; the ResNeSt Module adjusts the weight of each channel, increasing the ability of banana disease feature extraction and effectively reducing the error rate of similar disease identification; the model's computational speed is increased using the hybrid activation function of RReLU and Swish. Our model achieves an average accuracy of 96.98% and a precision of 89.31% applied to 13021 images, demonstrating that the proposed method can effectively identify banana leaf diseases.

Maize (Zea mays L.) can exhibit yield penalties as a result of unfavorable changes to growing conditions.  The main threat to current and future global maize production is heat stress.  Maize may suffer from heat stress in all of the growth stages, either continuously or separately.  In order to manage the impact of climate driven heat stress on the different growth stages of maize, there is an urgent need to understand the similarities and differences in how heat stress affects maize growth and yield in the different growth stages.  For the purposes of this review, the maize growth cycle was divided into seven growth stages, namely the germination and seedling stage, early ear expansion stage, late vegetative growth stage before flowering, flowering stage, lag phase, effective grain-filling stage, and late grain-filling stage.  The main focus of this review is on the yield penalty and the potential physiological changes caused by heat stress in these seven different stages.  The commonalities and differences in heat stress related impacts on various physiological processes in the different growth stages are also compared and discussed.  Finally, a framework is proposed to describe the main influences on yield components in different stages, which can serve as a useful guide for identifying management interventions to mitigate heat stress related declines in maize yield.

Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops, regulated by the synergy of endogenous (genetic) and exogenous (environmental) factors.  The physiological and molecular regulation of tillering has been intensively studied in rice and wheat.  However, tillering research on barley is scarce.  This review used the recent advances in bioinformatics to map all known and potential barley tiller development genes with their chromosomal genetic and physical positions.  Many of them were mapped for the first time.  We also discussed tillering regulation at genetic, physiological, and environmental levels.  Moreover, we established a novel link between the genetic control of phytohormones and sugars with tillering.  We provided evidence of how environmental cues and cropping systems help optimize the tiller number.  This comprehensive review enhances the understanding of barley’s physiological and genetic mechanisms controlling tillering and other developmental traits.

Agropyron cristatum (2n=4x=28, PPPP) is a wild relative of common wheat which contains a large number of desirable genes that can be exploited for wheat improvement.  Wheat–A. cristatum 2P alien translocation lines exhibit many desirable traits, such as small flag leaves, a high spikelet number and density, and a compact plant type.  An agronomic trait evaluation and a genetic analysis were carried out on translocation lines and backcross populations of these lines carrying different translocation fragments.  The results showed that a translocation fragment from 2PT-3 (2PL) reduced the length of the flag leaves, while translocation fragments from 2PT-3 (2PL) and 2PT-5 (2PL (0.60–1.00)) reduced the width of the flag leaves.  A translocation fragment from 2PT-13 (2PS (0.18–0.36)) increased the length and area of the flag leaves.  Translocation fragments from 2PT-3 (2PL) and 2PT-8 (2PL (0.86–1.00)) increased the density of spikelets.  Translocation fragments from 2PT-7 (2PL (0.00–0.09)), 2PT-8 (2PL (0.86–1.00)), 2PT-10 (2PS), and 2PT-13 (2PS (0.18–0.36)) reduced plant height.  This study provides a scientific basis for the effective utilization of wheat–A. cristatum translocation lines.