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Insufficient pollination is one of the direct causes of flower and fruit drop in goji berries. Aiming to determine the flowering characteristics, 'Ningqi 10' was taking as material to analyze flowering period, including flower color, stigma receptivity, pollen vitality, and nectar secretion at different stages. The study also analyzed the pollination characteristics of common pollinating insects, such as the duration of a single visit to flowers and the number of pollen deposition on the stigma. The results showed that during 12~24 h after flowering and the petal color changed to light purple and white purple, the stigma receptivity, pollen vitality, and nectar secretion were the highest, with significant differences (P<0.05) compared to other stages. The number of pollen deposition on the stigma of common pollinating insects after a single visit (moths>bees>non cushioned bees) showed significant differences compared to natural pollination. The average duration of bees visiting purple flowers was 4.1 s, and the difference was extremely significant (P<0.01) compared to the duration of bees visiting yellow flowers (average 1.7 s). The number of pollen deposition on the stigma of common pollinating insects after a single visit to flowers (moths>bees>non cushioned bees) showed significant differences compared to natural pollination. However, in terms of overall efficiency and the number of pollinating insect visits, it was recommended to introduce pollinating insects (such as bees) to enhance the assisted pollination of goji berries and improve the fruit setting and seed setting of 'Ningqi 10'. The research results provided scientific basis for the development of assisted pollination measures for goji berries. [ABSTRACT FROM AUTHOR]

Abstract [Objective] PEX (pollen extensin-like) gene is involved in controlling pollen development, which plays a crucial role in embryogenesis of pollen microspores and haploid culture. In this study, the authors isolated the CaPEX3 gene from pepper and analyzed its protein structure and expression pattern, which provides a theoretical foundation for further investigation into the function of the CaPEX3 gene. [Methods] CaPEX3 was cloned by PCR, and its protein structure, evolution, and gene regulation were analyzed by bioinformatics. Expression of CaPEX3 in different tissues and pollen of different varieties were detected by qRT-PCR. Pollen viability of different pepper varieties was detected by staining method and their relationship with CaPEX3 expression was analyzed. [Results] The coding region of CaPEX3 was 1 581 bp in length, encoding 526 amino acids, which belongs to the LRX (leucine-rich repeats/extensins) gene family. The protein had phosphorylation and glycosylation sites, signaling peptides, and transmembrane domains. The expression level of CaPEX3 was the highest in flowers, and the gene expression was higher in tissues with high pollen vitality. The regulatory network predicted that CaPEX3 might be involved in the regulation of pollen development through the action of genes related to flower development. [Conclusion] CaPEX3 was specifically expressed in flowers, and a correlation was observed between its expression level and the activity of pollen grains. The analysis of gene expression and the construction of related vectors provided a theoretical foundation and technical support for the subsequent investigation of gene function and mechanism of CaPEX3

Watermelon (Citrullus lanatus) holds global significance as a fruit with high economic and nutritional value. Exploring the regulatory network of watermelon male reproductive development is crucial for developing male sterile materials and facilitating cross-breeding. Despite its importance, there is a lack of research on the regulation mechanism of male reproductive development in watermelon. In this study, we identified that ClESR2, a VIIIb subclass member in the APETALA2/Ethylene Responsive Factor (AP2/ERF) superfamily, was a key factor in pollen development. RNA in situ hybridization confirmed significant ClESR2 expression in the tapetum and pollen during the later stage of anther development. The pollens of transgenic plants showed major defects in morphology and vitality at the late development stage. The RNA-seq and protein interaction assay confirmed that ClESR2 regulates pollen morphology and fertility by interacting with key genes involved in pollen development at both transcriptional and protein levels. These suggest that Enhancer of Shoot Regeneration 2 (ESR2) plays an important role in pollen maturation and vitality. This study helps understand the male reproductive development of watermelon, providing a theoretical foundation for developing male sterile materials.

Abstract Globe artichoke (Cynara cardunculus var. scolymus; 2n = 2x = 34) is a food crop consumed for its immature flower heads. Traditionally, globe artichoke varietal types are vegetatively propagated. However, seed propagation makes it possible to treat the crop as annual, increasing field uniformity and reducing farmers costs, as well as pathogens diffusion. Despite globe artichoke’s significant agricultural value and the critical role of heterosis in the development of superior varieties, the production of hybrids remains challenging without a reliable system for large-scale industrial seed production. Male sterility (MS) presents a promising avenue for overcoming these challenges by simplifying the hybridization process and enabling cost-effective seed production. However, within the Cynara genus, genic male sterility has been linked to three recessive loci in globe artichoke, with no definitive genetic mechanism elucidated to date. A 250 offsprings F2 population, derived from a cross between a MS globe artichoke and a male fertile (MF) cultivated cardoon (C. cardunculus var. altilis) and fitting a monogenic segregation model (3:1), was analyzed through BSA-seq, aiming at the identification of genomic regions/genes affecting male sterility. Four QTL regions were identified on chromosomes 4, 12, and 14. By analyzing the sequence around the highest pick on chromosome 14, a cytochrome P450 (CYP703A2) was identified, carrying a deleterious substitution (R/Q) fixed in the male sterile parent. A single dCAPS marker was developed around this SNP, allowing the discrimination between MS and MF genotypes within the population, suitable for applications in plant breeding programs. A 3D model of the protein was generated by homology modeling, revealing that the mutated amino acid is part of a highly conserved motif crucial for protein folding.

Wuren walnut is a unique germplasm resource of Juglans sigilata in Guizhou Province, named after its purple and black seed coat. It is a typical medicinal and edible plant with high nutritional value and good taste compared with ordinary walnut. The color of its inner seed coat is different from that of ordinary walnut, which is mostly light yellow. Wuren walnut has great market potential for development. To lay a theoretical foundation for the future breeding of improved varieties, pollination tree configuration, and hybrid breeding of Wuren walnut in Guizhou Province, this paper summarized the current research status of pollen vitality and stigma acceptability of Guizhou Wuren walnut in recent years, and looked forward to future research and application. [ABSTRACT FROM AUTHOR]

Drought stress is detrimental to male reproduction in maize (Zea mays L.), largely through reducing the quantity and quality of pollen grains. However, transcriptional response of maize pollen grains to drought stress has not been well documented. We compared pollen gene expression for a maize hybrid (ZhongDan909) under well-watered and drought-stress conditions, based on RNA-Seq validated by quantitative real-time PCR analysis. Expression of 6424 genes and 1302 transcripts was altered in pollen grains of maize subjected to 7 days of drought during flowering. Gene Ontology annotations showed 308 differentially expressed genes, annotated and classified into 50 primary functional categories. Kyoto Encyclopedia of Genes and Genomes analyses revealed 44 differentially expressed genes in nine metabolic pathways. In relation to carbohydrate metabolism pathways, there was downregulation of a polygalacturonase gene, which could reduce cell wall lysis in early pollen germination, and an increase in callose synthase transcripts along with reduced cellulase transcripts. These altered gene expressions responsible for cell wall integrity may inhibit the initiation of pollen tube growth. The onset of tube growth could be further impeded by observed changes in gene expression that potentially influence hormone metabolism (including downregulation of AUXIN RESPONSE FACTOR 18 and EIN3-BINDING F-BOX), reduce mitochondrial function, and alter protein translation. Genes with potential roles in adaptation were also altered in their transcript levels. These included genes encoding the upregulated transcription factor ZmNF-YC2, and the downregulated ZmbHLH13, a negative regulator of jasmonic acid responses. The upregulated flavin enzyme gene DIHYDROLIPOYL DEHYDROGENASE 1, associated with increased levels of reactive oxygen species, is of interest in relating redox homeostasis to stress adaptation. Overall, the analyses identified a suite of genes involved in the development of pollen grains and tubes and responsive to drought stress. The findings enhance understanding of the gene networks underlying compromised pollen viability under drought stress. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

2, 3-bisphosphoglycerate-independent phosphoglycerate mutase (iPGAM), is a key enzyme that catalyzes the reversible interconversion of 3-phosphoglycerate and 2-phosphoglycerate in glycolysis. iPGAM has been found to be involved in several physiological processes, including stomatal movement, chlorophyll synthesis, pollen production, chloroplast development and photosynthesis in different plants. However, the roles iPGAM plays in model plant tobacco are still elusive. In the current study, two copies of the iPGAM gene in Nicotiana tabacum were cloned, NtiPGAMa and NtiPGAMb, from the variety "Honghuadajinyuan". Expression profiles and subcellular localization analyses showed that NtiPGAMa and NtiPGAMb were highly expressed in the anthers and were localized to the nucleus, cytosol and cell membrane. Using the CRISPR/Cas9 system, three mutant lines with mosaic leaves were obtained by targeting the second exon of the iPGAM gene. Based on Sanger sequencing, the mutant lines were chimeric plants and displayed mutation rates ranging from 82.3% to 92.5%. The iPGAM mutations showed significantly decreased photosynthetic pigments, i.e., chlorophyll a, chlorophyll b and carotenoids, thinning or loss of chloroplast thylakoid lamellar structures. RT-PCR analysis showed that the expressions of genes associated with chlorophyll synthesis and photosynthesis were significantly down-regulated in the iPGAM mutant plants compared to wild type. The pollen development was greatly impaired in mutant plants, resulting in reduced and deformed pollens with grains inviable. Our findings indicate that iPGAM is critical for pollen vitality, chlorophyll synthesis and chloroplast morphogenesis in N. tabacum. [ABSTRACT FROM AUTHOR]

Owing to the wide variation in their morphological characteristics across diverse geographies, the identification and classification of plants in the Nymphaea genus are challenging. Therefore, the present study investigated the pollen morphological characteristics of hardy water lilies (N. ‘Rose Arey’, N. ‘Perry’s Fire Opal’, and N. ‘Peter Slocum’), their relationship with species classification and system evolution, and their cross-compatibility with three strains of Nymphaeahybrid (NH-1, NH-2, and NH-3), a tropical waterlily. Pollen of the hardy water lilies was single-grained, oblate, and 18.31–20.47 × 32.51–37.64 μm. The pollen apertures were of the ring-groove type, and the pollen exine ornamentation was rod- and tumour-shaped. Pollen grains of different species differed in size, the obviousness of tumour ornamentation, and the size and density of rod-like ornamentation; their germination rates also differed significantly. Viabilities of N. ‘Rose Arey’ and N. ‘Peter Slocum’ pollen were the highest and lowest, respectively. According to the artificial pollination results, all hybrid combinations except three (NH-1 × N. ‘Peter Slocum’, NH-2 × N. ‘Peter Slocum’, and NH-3 × N. ‘Peter Slocum’) bore seeds; combinations with NH-2 as the female parent and N. ‘Rose Arey’ as the male parent had the highest seed-setting rates.

Guangxi is one of the distribution centers of Primulina of the world. There are many endemic species. For the purpose of introdution and cultivation, germplasm presrvation and hybridization breeding, this study focused on the flow, ering phenological period, flowering habit, ovary development, pollen activity and other flowering biological characteris, tics of eight Primulina species endemic to Guangxi, including Primulina linearifolia, P. ophiopogoide, P. spinulosa, P. macrorhiza, P. linearicalyx, P. leprosa, P. guizhongensis and P. baishouensis. The results were as follows: (1) There were significant differences between in the wild and the artifical conditions in the flowering period, single bud blooming amount and single flower opening duration of these eight endemic species in Guangxi. In artificial conditions, the amount of flowering per plant and the duration of flower blooming were better than those of wild plants. (2) The duration of single flowering period of different species was 3-14 d. The stamens stopped growth in bud stage. The maturities of pistils and stamens were inconsistent, the stamens matured earlier than the pistils. (3) The pollen vitality was increasing from half-open to fully,open stage, which could reach more than 90% in fully,open stage. (4) The stigma was most compatible in the fully-opend stage of the corolla. At corolla completely open stage, the stigma receptivity rised to the highest level. (5) Self pollination was sterile, cross pollination was fertile. The seed germination rate of crossing seeds was more than 80%. This study provides data to support the multiplication of rare species and germplasm resources preservation, and also provides solutions for hybridization breeding in Primulina. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The phenotype of the tomato mutant jasmonate-insensitive1-1 (jai1-1) mutated in the JA-Ile co-receptor COI1 demonstrates JA function in flower development, since it is female-sterile. In addition, jai1-1 exhibits a premature anther dehydration and pollen release, being in contrast to a delayed anther dehiscence in the JA-insensitive Arabidopsis mutant coi1-1. The double mutant jai1-1 Never ripe (jai1-1 Nr), which is in addition insensitive to ethylene (ET), showed a rescue of the jai1-1 phenotype regarding pollen release. This suggests that JA inhibits a premature rise in ET to prevent premature stamen desiccation. To elucidate the interplay of JA and ET in more detail, stamen development in jai1-1 Nr was compared to wild type, jai1-1 and Nr regarding water content, pollen vitality, hormone levels, and accumulation of phenylpropanoids and transcripts encoding known JA- and ET-regulated genes. For the latter, RT-qPCR based on nanofluidic arrays was employed. The data showed that additional prominent phenotypic features of jai1-1, such as diminished water content and pollen vitality, and accumulation of phenylpropanoids were at least partially rescued by the ET-insensitivity. Hormone levels and accumulation of transcripts were not affected. The data revealed that strictly JA-regulated processes cannot be rescued by ET-insensitivity, thereby emphasizing a rather minor role of ET in JA-regulated stamen development.

In or(Ker to select tlie afinity oi Brassica rapa，Brassica juncea，and G distant hybridization，the ratio of pod setting，ratio of seed setting， pollen vitality cere measured and crossing-compatibility of 52 different Hybrids cas analyzed in this study. The results showed that: From the cluster analysis diagram of pod rate and affinity index with 52 different Hybrids，the ratio of pod setting and ratio of seed setting，different varieties of winter oilseed rape showed that B. /unca × B. rapa > B. juncee × B. napus > B. rapa × B. juncee > B.na-pus × B. juncea. The results of pollen vitality of different Brassica hybrids showed that B. juncea × B. rapa > B. juncea × B. napus > B. rapa qB. juncea > B. napus × B. juncea. The results of analysis of Crossing-compatibility showed that the maximum adhesion of pollen on the stigma of B. juncea × B. rapa and B. .imcea × B. napus，Pollen was also the shortest time to stay，Pollen germination the fastest. The second was B. rapa × B. juncea. But there were a handful of pollen on the stigma of B. napu × B. juncea. Pollen was also the long time to stay，Pollen germination the slowest. There were a lot of Callose under a fluorescence microscope. Therefore，B. juncea was most suitable for female among the B. rapa，B. .uncea，and B . napus. The second was B. rapa，B. napu most difficult female parent among the B. rapa，B. juncea， and B napus. [ABSTRACT FROM AUTHOR]

The pollen/ovule (P/O) ratio has been used as predictor of the reproductive system of angiosperms (lowest P/O values correspond to obligate autogamous species while the highest correlate with obligate xenogamous species) but it does not keep for all the taxa. The relation of P/O index with pollen and stigma size, flower diameter, pollen vitality, stigmatic area/pollen-bearing area of the pollinators ratio (SA/PBA), taxonomy and breeding system was analyzed in four Passiflora species with different degree of compatibility, pollination system and taxonomic placement. P/O of the self-compatible species (with shorter anthesis, scarce pollinator visits or minor longevity) was lower than P/O of the self-incompatible ones. The P/O values of the outcrossers could be related with the highly efficient pollination performed by the frequently visiting Xylocopa species; these bees transport Passiflora pollen in a usually monospecific mass on the thorax, resembling grouped pollen dispersal. All the taxa exhibited pollen with unimodal size and high vitality, except for P. misera, in which pollen size was bimodal, with similar quantities of grains in both classes, the large being more vital than the small ones. Correlations of P/O were positive with flower size, negative with stigma area/pollen-bearing area of the pollinator, null with stigma area and not significant with pollen size. The P/O ratio did not reflect taxonomic affinities; this index and the breeding system were more related with pollinator type, anthesis, flower size and SA/PBA than with pollen grain or stigma size.

Owing to the wide variation in their morphological characteristics across diverse geographies, the identification and classification of plants in the Nymphaea genus are challenging. Therefore, the present study investigated the pollen morphological characteristics of hardy water lilies (N. 'Rose Arey', N. 'Perry's Fire Opal', and N. 'Peter Slocum'), their relationship with species classification and system evolution, and their cross-compatibility with three strains of Nymphaeahybrid (NH-1, NH-2, and NH-3), a tropical waterlily. Pollen of the hardy water lilies was single-grained, oblate, and 18.31–20.47 × 32.51–37.64 μm. The pollen apertures were of the ring-groove type, and the pollen exine ornamentation was rod- and tumour-shaped. Pollen grains of different species differed in size, the obviousness of tumour ornamentation, and the size and density of rod-like ornamentation; their germination rates also differed significantly. Viabilities of N. 'Rose Arey' and N. 'Peter Slocum' pollen were the highest and lowest, respectively. According to the artificial pollination results, all hybrid combinations except three (NH-1 × N. 'Peter Slocum', NH-2 × N. 'Peter Slocum', and NH-3 × N. 'Peter Slocum') bore seeds; combinations with NH-2 as the female parent and N. 'Rose Arey' as the male parent had the highest seed-setting rates. [ABSTRACT FROM AUTHOR]

The study is aimed to investigate the reproductive biology characteristics of Polygonatum cyrtonema, especially including phenology, flower bud differentiation, flowering timing, floral traits, pollen vigor and stigma receptivity. The results showed that P. cyrtonema forms inflorescence before the leaves spread. In the wild, P. cyrtonema is mainly pollinated by insects such as bumblebees, with a seed setting rate of 65.12%. The seed setting rate of indoor single plant isolation or self-pollination enclosed by parchment paper bag is 0, indicating that it is self-incompatible. In Lin'an city, seedlings begin to emerge from mid-March to early April(the temperature is higher than 7.5 ℃), buds begin to emerge from the end of March to mid-April, and then undergo the full bloom stage from mid-to-late April, and the final flowering stage from the end of April to mid-May. The whole flowering period lasts 36 to 45 days. There are obvious differences in the phenology of different provenances. The flowers come into bloom from the base to the top along the aboveground main axis, which usually contain 4-22 inflorescences with(2-) 4-10(-21) flowers per inflorescence. The flowering pe-riod for a single plant is 26-38 days. The single flower lasts about 20-25 days from budding to opening and withers 2 days after pollination, and then the ovary will gradually expand. If unpollinated, it will continue to bloom for 3-5 days and then wither. Flower development period is significantly related to pollen vigor and stigma remittance. The pollen viability is the highest when the flower is fully opened with anthers gathering on the stigma, and the receptivity is the strongest when the stigma protrudes out of the perianth and secretes mucus. The fruits and seeds ripen in October, and proper shading can ensure the smooth development and maturity of the seeds. This study provides a basis for the hybrid breeding and seed production of P. cyrtonema.

The phenotype of the tomato mutant jasmonate-insensitive1-1 (jai1-1) mutated in the JA-Ile co-receptor COI1 demonstrates JA function in flower development, since it is female-sterile. In addition, jai1-1 exhibits a premature anther dehydration and pollen release, being in contrast to a delayed anther dehiscence in the JA-insensitive Arabidopsis mutant coi1-1. The double mutant jai1-1 Never ripe (jai1-1 Nr), which is in addition insensitive to ethylene (ET), showed a rescue of the jai1-1 phenotype regarding pollen release. This suggests that JA inhibits a premature rise in ET to prevent premature stamen desiccation. To elucidate the interplay of JA and ET in more detail, stamen development in jai1-1 Nr was compared to wild type, jai1-1 and Nr regarding water content, pollen vitality, hormone levels, and accumulation of phenylpropanoids and transcripts encoding known JA- and ET-regulated genes. For the latter, RT-qPCR based on nanofluidic arrays was employed. The data showed that additional prominent phenotypic features of jai1-1, such as diminished water content and pollen vitality, and accumulation of phenylpropanoids were at least partially rescued by the ET-insensitivity. Hormone levels and accumulation of transcripts were not affected. The data revealed that strictly JA-regulated processes cannot be rescued by ET-insensitivity, thereby emphasizing a rather minor role of ET in JA-regulated stamen development. [ABSTRACT FROM AUTHOR]