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When reproductive success is determined by the relative availabilities of a series of essential, non-substitutable resources, the theory of balanced fitness limitations predicts that the cost of harvesting a particular resource shapes the likelihood that a shortfall of that resource will constrain realized fitness. Plant reproduction through female function offers a special opportunity to test this theory; essential resources in this context include, first, the pollen received from pollinators or abiotic vectors that is used to fertilize ovules, and, second, the resources needed to provision the developing seeds and fruit. For many plants realized reproductive success through female function can be readily quantified in the field, and one key potential constraint on fitness, pollen limitation, can be assessed experimentally by manually supplementing pollen receipt. We assembled a comparative dataset of pollen limitation using only studies that supplement pollen to all flowers produced over the plants reproductive lifespan. Pre- and post-pollination costs were estimated using the weight of flowers and fruits and estimates of fruit set. Consistent with expectations, we find self-incompatible plants make greater pre-pollination investments and experience greater pollen limitation. However, contrary to theoretical expectations, when variation due to self-compatibility is accounted for by including self-compatibility in the statistical model as a covariate, we find no support for the prediction that plants that invest more heavily in pre-pollination costs are subject to greater pollen limitation. Strong within-species, between-population variation in the expression of pollen limitation makes the quantification of mean pollen limitation difficult. We urge plant ecologists to conduct more studies of pollen limitation using whole-plant pollen supplementation to produce a richer comparative dataset that would support a more robust test of the balanced limitations hypothesis.

During the process of almond (Prunus dulcis) domestication, essential traits, which gave plants the plasticity for facing unstable environmental conditions, were lost. In general, the domestication process often narrows the natural genetic diversity. Modern selections (i.e., breeding programs) dramatically accelerated this genetic bottleneck trend to a few successful almond cultivars, which are presently the founders of most commercial cultivars worldwide. The concept of utilizing wild species as a source for important traits and for the enrichment of the gene pool was deeply discussed in previous studies. However, in almonds and other Prunus species, deliberate utilization of wild species as a genetic resource for breeding programs is quite rare. To address these significant challenges, we generated an interspecific F1 population between the Israeli almond cultivar Um el Fahem (UEF) and a specimen of a local wild almond species, Prunus arabica (P. arabica), originating from the Judea desert. This interspecific F1 population possesses high phenotypic variability, and sixteen segregating traits were phenotyped. Among the segregating traits, we were able to genetically associate six agriculturally important traits, such as leaf chlorophyll content (LCC), flower size, and fruit size. The alleles for Self-Compatibility (SC) and kernel bitterness were previously mapped in almond and were reexamined on the background of the distinctive wild genetic material of P. arabica. Finally, phenotypic interactions between traits were suggested, such as rootstock perimeter and canopy area that were positively correlated with total yield in the F1 population. This study is a first step towards developing a well-characterized almond interspecies genetic population. The availability of such a genetic tool with detailed phenotypic analysis is crucial to address and explore the profound influence of almond wild species in Prunus genetic research and breeding. By using the interspecific population as the infrastructure, we show the advantages and importance of utilizing wild relatives. [ABSTRACT FROM AUTHOR]

To breed a Gogi Berry cultivar with high quality and high yield, CBP14639-56, as a Gogi Berry line, was selected from the hybrids(F1) of ‘CBP11542-206 (IT345448)’ and ‘CBP07445-64 (IT258918)’in 2015. The preliminary and the advanced yield were conducted to investigate yield characteristics during 2016 to 2017 and the selected line was named Cheongyang No. 34. The regional yield trials of Cheongyang No. 34 were performed at Cheongyang, Yesan and Geumsan areas during 2018 to 2020. As a result, Cheongyang No. 34 was registered as the new variety, ‘Hwaseon’. The specific characteristics of ‘Hwaseon’ are as follows. The type of tree is half opened shape and leaves are green and round-lanceolate. The observed flowering time is June 18, later than the comparative variety ‘Chengmyeong’. The shape of fruits is red, long oval type and a large fruit species. Self-compatibility rate was 71.7%, which was very high compared to 2.8% of the comparative variety, ‘Cheongmyeong’. The resistance against gall mite (Eriophyes spp.) was stronger. The content of betaine, the indicator component, was similar to the comparative variety, and the dried-fruit yield increased by 41% compared to ‘Cheongmyeong’ in the regional yield trials. The Gogi Berry ‘Hwaseon’ is a Self-compatibility variety that does not require mixing of pollinated varieties, and it is expected to help farmers growing Gogi Berry, who are suffering from low fertilization rates due to the recent decrease pollinating insect such as honeybees due to climate change and a decrease in high-temperature activity (Registration No. 9181). [ABSTRACT FROM AUTHOR]

Lycoris aurea is a perennial herbaceous plant with important medicinal and ornamental values in the genus Lycoris Herb, the family Amaryllidaceae. The flower has a spider shape with highly exserted stigmas and anthers, which may represent a unique pollination type. In order to explore this type of pollination, we studied its floral characteristics, breeding system, and floral visitors and their behaviors. The results were as follows: (1) The single flower lasted (5.9±0.1) d and the pollen-ovule ratio (P/O) reached about 23 000. The flowers showed reverse herkogamy. On the beginning of flowering, the style and filaments were separated and the angle between them was about 30°. The style gradually moved towards the filaments in the middle and later stages and were finally on the same line with the stigma 2-3 cm higher than the anthers. The stigmas were receptive throughout the flowering period. (2) The breeding system test was self-compatible and bagged flowers cannot set fruit, indicating that pollinators were necessary for pollen transfer. Supplemental hand pollination significantly increased fruit production, indicating the existence of pollen limitation. (3) Four species of swallowtail butterfly were the effective pollinators. Due to the existence of herkogamy in L. aurea, on the beginning of flowering, their hindwings were likely to come into contact with the flattened anthers. Their hindwings might touch the stigma in the middle and later stages and thus the process of pollen transfer was accomplished. In conclusion, this study shows that the uqique floral characteristics of L. aurea are adapted for butterfly wing pollination and also will lay the foundation for its conservation and sustainable utilization. [ABSTRACT FROM AUTHOR]

Context: Knowledge of the reproductive biology of plants is fundamental for conservation, especially of the ones with a limited distribution. Aims: The sexual reproduction of the small-ranged Passiflora chrysophylla Chod. was studied. Methods: Controlled pollinations were performed to assess the breeding system, whereas floral traits and visitors (identity, frequency, activity on the flowers, dimensions and pollen load) were analysed to assess the pollination mechanism. Key results: Self-compatibility was partial. Anthesis was matinal. The odour emitted by the corona was sweet, whereas the odour emitted by the persistent sepals and bracts was similar to that of the leaves. Contrasting concentric circular reward guides were present in the visible and UV spectra. Nectar concentration was high, the volume increased throughout anthesis and, if removed, nectar was replenished only once during the flower lifespan. Style movements towards the anthers determined male and hermaphroditic phases in most of the flowers; in a few flowers (smaller, scented and nectarless), styles remained apart from the anthers, thus constituting a functionally andromonecious and deceptive automimicry system. The bees Ptiloglossa sp., Thygater analis and Xylocopa augusti acted as pollinators, whereas ants, butterflies and beetles were nectar or pollen thieves and florivores. Conclusions: P. chrysophylla is melittophilous and pollinators increase reproductive success. Implications: Pollination biology of P. chrysophylla , reported for the first time, would contribute to conservation management of this species with restricted distribution. The pollination of the tiny passion vine Passiflora chrysophylla , a small-ranged species from the southern hemisphere, has been studied for the first time. Its sexual reproduction and, consequently, its genetic variability, is partially dependant on native bees, mainly crepuscular ones, to which it offers highly concentrated nectar during the morning. Its floral biology is similar to that of its close relative P. foetida , which is widespread, even invasive, and provides useful information in case of conservation needs. Photograph by P. I. Picca. [ABSTRACT FROM AUTHOR]

SUMMARY: The successful interaction between pollen and stigma is a critical process for plant sexual reproduction, involving a series of intricate molecular and physiological events. After self‐compatible pollination, a significant reduction in reactive oxygen species (ROS) production has been observed in stigmas, which is essential for pollen grain rehydration and subsequent pollen tube growth. Several scavenging enzymes tightly regulate ROS homeostasis. However, the potential role of these ROS‐scavenging enzymes in the pollen‐stigma interaction in Brassica napus remains unclear. Here, we showed that the activity of ascorbate peroxidase (APX), an enzyme that plays a crucial role in the detoxification of hydrogen peroxide (H2O2), was modulated depending on the compatibility of pollination in B. napus. We then identified stigma‐expressed APX1s and generated pentuple mutants of APX1s using CRISPR/Cas9 technology. After compatible pollination, the BnaAPX1 pentuple mutants accumulated higher levels of H2O2 in the stigma, while the overexpression of BnaA09.APX1 resulted in lower levels of H2O2. Furthermore, the knockout of BnaAPX1 delayed the compatible response‐mediated pollen rehydration and germination, which was consistent with the effects of a specific APX inhibitor, ρ‐Aminophenol, on compatible pollination. In contrast, the overexpression of BnaA09.APX1 accelerated pollen rehydration and germination after both compatible and incompatible pollinations. However, delaying and promoting pollen rehydration and germination did not affect the seed set after compatible and incompatible pollination in APX1 pentuple mutants and overexpression lines, respectively. Our results demonstrate the fundamental role of BnaAPX1 in pollen rehydration and germination by regulating ROS homeostasis during the pollen‐stigma interaction in B. napus. Significance Statement: Our research found that self‐incompatibility in Brassica napus requires the accumulation of reactive oxygen species (ROS) levels in the stigma. We identified the importance of BnaAPX1 in regulating ROS homeostasis, which is critical for pollen rehydration and germination in B. napus. [ABSTRACT FROM AUTHOR]

The article provides information on the development and characteristics of the Felama VR almond cultivar, which is a self-compatible and late-flowering cultivar with high fruit quality. It is suitable for areas without the risk of spring frost. The article also includes references on various topics related to almond cultivation, such as endodormancy break, macroelement exports, blooming requirements, gene expression analysis, incompatibility genotypes, architectural traits, phenolic compounds, and antioxidant capacity. Additionally, there is a table showing the oil and fatty acid composition of different almond genotypes, including the O/L factor used to assess oil quality. [Extracted from the article]

IntroductionNoug (Guizotia abyssinica) is an economically important edible oilseed crop in Ethiopia with a large variation in seed set, seed oil content, and fatty acid composition among populations. Although noug is generally strictly self-incompatible (SI), self-compatible (SC) lines were recently developed. This study was conducted to investigate the levels of variation in seed setting and oleic acid content among the self-compatible lines.MethodsThe starting materials for the seed setting study were 200 genotypes selected from 100 inbred lines and having, on average, 57 seeds per capitulum, which is higher than that of the SI populations. The SC genotypes were analyzed for their oleic acid content using the half-seed technique.ResultsThe analysis of 20 SC lines revealed a high variation in oleic acid content with 70% of the SC lines having 20% or more oleic acid after they were grown under 25°C/21°C day/night temperatures (high-temperature treatment). The oleic acid content increased from 8.2% before to 22.5%, on average, after the high-temperature experiment in the greenhouse. In contrast, the percentage of oleic acid in these lines grown at 21°C/18°C day/night temperatures decreased from 8.2% to 4.4% on average. There was a highly significant positive correlation between oleic acid content and temperature in SC lines.ConclusionThe study suggests a significant contribution of genotype to the variation in seed setting and environmental factors (mostly temperature) to the oleic acid content. The noug SC-lines showed highly significant variation in seed setting and oleic acid content, which could be used for improving the crop’s seed yield and oil quality.

Abstract: Letícia AF is a mutation of the plum cultivar Laetitia that confers self-compatibility. This work compared the Letícia AF mutant cultivar with the standard Laetitia regarding fruit set, self-compatibility, yield, and fruit quality traits during four growing seasons. The study was carried out in two plum orchards with the cultivar Letícia AF (orchard 1) and Laetitia plus pollinizers trees (orchard 2) and in an experimental unit with Letícia AF and Laetitia planted side by side. A self-compatibility test was performed on covered branches to prevent pollinating insects from reaching the flowers. Fruit set occurs in covered branches of Letícia AF, whereas it was rare in Laetitia. In commercial orchards, Leticia AF plums yield was higher than that of Laetitia over the years. The results suggest that the oscillation in productivity across the years, mainly due to unfavorable conditions for insect pollination, may be lower in the plum Leticia AF orchard. On the other hand, the requirement for fruit thinning may be greater in Leticia AF. No significant differences were found between the mutant and the standard cultivar regarding fruit quality at harvest and after 30 days of cold storage, indicating the mutation did not alter the fruit characteristics.

The productivity of many tree crops is limited by low yield, partly due to high rates of fruitlet abscission during early fruit development. Early studies suggested that cross-pollinated fruitlets may be selectively retained during fruit development, although paternity testing of fruitlets to test this hypothesis was technically challenging. We used MassARRAY genotyping to determine the effects of pollen parentage on fruitlet retention and fruit quality of Hass avocado. We identified the paternity of abscised and retained fruitlets at 6 and 10 weeks, and mature fruit at 36 weeks, after peak anthesis. We measured the embryo mass, pericarp mass, total mass and nutrient concentrations of fruitlets, and the seed mass, flesh mass, total mass, diameter, length, nutrient concentrations and fatty-acid composition of mature fruit. The percentages of progeny on the tree that were cross-fertilised increased from 4.6% at 6 weeks after peak anthesis to 10.7% at fruit maturity. Only 1.0% of freshly abscised fruitlets on the ground at 10 weeks after peak anthesis were cross-pollinated even though 6.5% of retained fruitlets on the tree were cross-pollinated. At this stage, cross-pollinated fruitlets had similar nutrient concentrations to self-pollinated fruitlets, but they had higher total contents of P, K, Al, Ca, Fe, Mn and Zn due to having greater fruitlet mass. At maturity, cross-pollinated fruit were 6% heavier and had 2% greater diameter than self-pollinated fruit, without significant differences in flesh nutrient concentrations or fatty acid composition. The results demonstrate that Hass avocado trees selectively retain cross-pollinated fruitlets, which are larger than self-pollinated fruitlets and ultimately produce larger mature fruit. Avocado growers can increase fruit size and yield by improving the opportunities for cross-pollination, possibly by closely interplanting type A and type B cultivars and introducing more beehives into orchards. [ABSTRACT FROM AUTHOR]

The Dwarf Palm, Butia lallemantii Deble & Marchiori, is an endangered species endemic to the Pampa biome and typically grows in sandy and rocky soils. Given its economic, ecological, and cultural relevance, it is crucial to understand the ecology and biology of this species to encourage its preservation and highlight its significance for the Pampa. This study aims to investigate whether this palm relies on animal vectors for pollination, analyze its breeding system, and propose strategies for its conservation and sustainable use. We conducted field observations on pollination ecology, identified floral visitors, and designed six breeding system experiments to test cross-compatibility, self-compatibility, and apomixis. Additionally, we conducted a literature review to propose conservation strategies. Butia lallemantii is pollinator-dependent and self-compatible. The flowers are mostly melittophilous and offer pollen and nectar for floral visitors. The main pollinators are native Meliponinae and Halictinae bees and the introduced Apis mellifera. This study represents the first comprehensive and complete examination of the breeding system and pollination process on Butia palms. This palm can provide materials for industries, but urgent actions are needed to preserve the remaining populations through effective policies and strategies. Furthermore, this palm should be integrated into diversified agroecosystems to evaluate its adaptability to cultivation. [ABSTRACT FROM AUTHOR]

The genus Dyckia (Bromeliaceae) is endemic to South America, and its species show important ecological roles in xeric environments. The flowering phenology as well as floral and reproductive biology were monitored monthly in Dyckia dissitiflora at two sites (Bela Vista: 11°42′03.4″ S 39°05′21.7″ W and Barra do Vento: 11°37′58.1″ S 39°03′33.7″ W) in the municipality of Serrinha, Bahia, Brazil. Flowering occurs in the early austral summer with a peculiar time of beginning of anthesis (10:00–11:00), offering resources 18 h after the first petal movements. Pollen viability was 98%, with a high production of pollen grains. Stigma receptivity is continuous from flower opening to senescence, and nectar production initiates at 04:00 and extends until 18:00. The species is self‐compatible and autogamous, but not agamospermic. Pollen tubes developed and reached the micropyle within 24 h in all of the reproductive tests. The hummingbird Chlorostilbon lucidus was the only floral visitor and pollinator (frequency = 0.82 ± 0.02). Fruiting occurs 3 days after anthesis, and the seeds are wind‐dispersed. Self‐compatibility and autogamy are essential strategies for the reproductive success of D. dissitiflora in light of the low number and visit frequency of its pollinators, and it is favored by slow floral movements and the position of the stigmas in relation to stamens. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia L.) is a monoecious species and although it exhibits self-compatibility, it presents incomplete overlap of pollen shed and female receptivity. Thus, cross-pollination is prerequisite for optimal fruit production. Cross-pollination can occur naturally by wind, insects, artificially, or by hand. Pollen has been recognized as one possible pathway for Xanthomonas arboricola pv. juglandis infection, a pathogenic bacterium responsible for walnut blight disease. Other than the well-known cultural and chemical control practices, artificial pollination technologies with the use of drones could be a successful tool for walnut blight disease management in orchards. Drones may carry pollen and release it over crops or mimic the actions of bees and other pollinators. Although this new pollination technology could be regarded as a promising tool, pollen germination and knowledge of pollen as a potential pathway for the dissemination of bacterial diseases remain crucial information for the development and production of aerial pollinator robots for walnut trees. Thus, our purpose was to describe a pollination model with fundamental components, including the identification of the "core" pollen microbiota, the use of drones for artificial pollination as a successful tool for managing walnut blight disease, specifying an appropriate flower pollination algorithm, design of an autonomous precision pollination robot, and minimizing the average errors of flower pollination algorithm parameters through machine learning and meta-heuristic algorithms. [ABSTRACT FROM AUTHOR]

Pollination of Dipcadi saxorum Blatt. was studied in Thane and Mumbai suburban districts, Maharashtra, India, during the flowering season from June to August for a period of two years. The flowers are nocturnal, producing scent and nectar at nightfall, which extends up to morning hours, attracting many visitors. The study shows that the species is self-incompatible and that its foul-acrid odour is mainly because of aldehydes and esters. Settling moths, Heliothus peltigera and Chrysodexis acuta, as well as hovering moths, Macroglossum stellatarum and Cephanodes hylas, are pollinators of D. saxorum Blatt. [ABSTRACT FROM AUTHOR]

Summary: Self‐incompatibility plays a vital role in angiosperms, by preventing inbreeding depression and maintaining genetic diversity within populations. Following polyploidization, many angiosperm species transition from self‐incompatibility to self‐compatibility.Here, we investigated the S‐locus in Brassicaceae and identified distinct origins for the sRNA loci, SMI and SMI2 (SCR Methylation Inducer 1 and 2), within the S‐locus. The SMI loci were found to be widespread in Cruciferae, whereas the SMI2 loci were exclusive to Brassica species.Additionally, we discovered four major S‐haplotypes (BnS‐1, BnS‐6, BnS‐7, and BnS‐1300) in rapeseed. Overexpression of BnSMI‐1 in self‐incompatible Brassica napus ('S‐70S1300S6') resulted in a significant increase in DNA methylation in the promoter regions of BnSCR‐6 and BnSCR‐1300, leading to self‐compatibility. Conversely, by overexpressing a point mutation of BnSmi‐1 in the 'S‐70S1300S6' line, we observed lower levels of DNA methylation in BnSCR‐6 and BnSCR‐1300 promoters. Furthermore, the overexpression of BnSMI2‐1300 in the 'SI‐326S7S6' line inhibited the expression of BnSCR‐7 through transcriptional repression of the Smi2 sRNA from the BnS‐1300 haplotype.Our study demonstrates that the self‐compatibility of rapeseed is determined by S‐locus sRNA‐mediated silencing of SCR after polyploidization, which helps to further breed self‐incompatible or self‐compatible rapeseed lines, thereby facilitating the utilization of heterosis. [ABSTRACT FROM AUTHOR]

Optimal fruit production from many tree crops relies on the transfer of cross-pollen between trees of different cultivars rather than the transfer of self-pollen between trees of the same cultivar. However, many orchards are established with wide blocks of single cultivars, which can result in high percentages of self-fertilised fruit and sub-optimal yield and quality. We aimed to determine whether outcrossing rates and yield of Hass avocado fruit decline with increasing distance from polliniser trees of cultivar Shepard and whether selfed fruit are smaller than outcrossed fruit. Outcrossing rates declined from 49% at six trees (40 m) from a block of Shepard trees to 30% at thirty trees (160 m) from a block of Shepard trees. Tree yield across this distance declined by 44% as a result of a 69% decline in the number of outcrossed fruit per tree, without a significant decline in the number of selfed fruit per tree. Outcrossed Hass fruit were 12% heavier than selfed Hass fruit, with 3% greater diameter and 5% greater length. The study results demonstrate the importance of interplanting Type B avocado pollinisers closely with Type A Hass trees to increase fruit yield and size. [ABSTRACT FROM AUTHOR]

Diploid inbred-based F1 hybrid True Potato Seed (DHTPS) breeding is a novel technique to transform potato breeding and cultivation across the globe. Significant efforts are being made to identify elite diploids, dihaploids and develop diploid inbred lines for heterosis exploitation in potatoes. Self-incompatibility is the first obstacle for developing inbred lines in diploid potatoes, which necessitates the introgression of a dominant S locus inhibitor gene (Sli) for switching self-incompatibility to self-compatibility. We evaluated a set of 357 diploid clones in different selfing generations for self-compatibility and degree of homozygosity using Kompetitive Allele Specific PCR (KASP) Single Nucleotide Polymorphism (SNP) markers. A subset of 10 KASP markers of the Sli candidate region on chromosome 12 showed an association with the phenotype for self-compatibility. The results revealed that the selected 10 KASP markers for the Sli gene genotype could be deployed for high throughput rapid screening of self-compatibility in diploid populations and to identify new sources of self-compatibility. The homozygosity assessed through 99 KASP markers distributed across all the chromosomes of the potato genome was 20–78 % in founder diploid clones, while different selfing generations, i.e., S0, S1, S2 and S3 observed 36.1–80.4, 56.9–82.8, 59.5–85.4 and 73.7–87.8 % average homozygosity, respectively. The diploid plants with ∼80 % homozygosity were also observed in the first selfing generation, which inferred that homozygosity assessment in the early generations itself could identify the best plants with high homozygosity to speed up the generation of diploid inbred lines.

ABSTRACTStrawberry flowers are hermaphroditic and most cultivars are self-compatible, but strawberry plants can produce a mixture of fruit that have arisen from self-pollination and cross-pollination. We aimed to determine whether size, shape, color, taste attributes and shelf life differ between self-pollinated and cross-pollinated fruit competing on the same Redlands Joy strawberry plant. Experiments were repeated at three fertilizer levels to determine the consistency of responses across different levels of crop nutrition. Cross-pollinated fruits were 4.2%–7.5% heavier and 2.7%–5.0% longer than self-pollinated fruits, with the differences being greater at lower levels of nutrient supply. They were also darker or redder than self-pollinated fruits. Cross-pollinated fruits sometimes had lower °Brix (sugar) or lower acidity than self-pollinated fruits, with the effect on sugar:acid ratio depending on the nutrient level. The shelf life of cross-pollinated fruits was approximately 4 days longer than self-pollinated fruits on plants that received medium or high levels of fertilizer. The results suggest that pollen-parent effects on fruit size become evident when self- and cross-pollinated strawberry fruits compete for resources on the same plant, and that the expression of pollen-parent effects can be affected by the level of crop nutrition.

Abstract Background The Convolvulaceae is a large family containing species exhibiting a range of breeding systems and pollinated by diverse animal taxa. We studied the pollination ecology of 15 Convolvulaceae species, representing seven genera (Argyreia Lour., Camonea Raf., Evolvulus L., Hewittia Wight & Arn., Ipomoea L., Merremia Dennst. ex Endl., and Operculina Silva Manso), in northeastern Thailand, a family that is highly diverse yet understudied in the paleotropics. Specifically, we studied their compatibility systems and degrees of pollinator dependency using pollination experiments, examined pollinator composition and visitation rates using video observation, and determined if there is an association between pollinator visitation rates and degree of pollinator dependence. Results Our results showed that most species are self-compatible, but the degree of pollinator dependence varies. Six species were found to be highly dependent on pollinators, as two are self-incompatible and four are self-compatible but had reduced seed set when pollinators were excluded, possibly due to herkogamy. Seven species showed low dependence on pollinators and seed set remained high when pollinators were excluded. Pollinator dependence was inconclusive for two species as seed set was low in all pollination treatments. We also found an association between pollinator visitation rates and degree of pollinator dependence. Specifically, species exhibiting high pollinator dependence received frequent visits from pollinators, while species exhibiting low pollinator dependence either received frequent visits from pollinators (and received high amounts of xenogamous pollen) or infrequent visits from pollinators (and received significantly lower amounts of xenogamous pollen). Most of our study species were primarily visited by bees (e.g., Lasioglossum, Amegilla, Apis, and meliponines), with the exception of one night-blooming species that was visited primarily by crepuscular butterflies and hawkmoths. Conclusions The cumulative findings of this study demonstrate how pollinator dependence is influenced by breeding system, and suggest that pollinator visitation is consistently high for species exhibiting high pollinator dependence but varies across species exhibiting low pollinator dependence. Our findings are also important for assessing the conservation risks of paleotropical Convolvulaceae.

Abstract When reproductive success is determined by the relative availabilities of a series of essential, non‐substitutable resources, the theory of balanced fitness limitations predicts that the cost of harvesting a particular resource shapes the likelihood that a shortfall of that resource will constrain realized fitness. Plant reproduction through female function offers a special opportunity to test this theory; essential resources in this context include, first, the pollen received from pollinators or abiotic vectors that is used to fertilize ovules, and, second, the resources needed to provision the developing seeds and fruit. For many plants realized reproductive success through female function can be readily quantified in the field, and one key potential constraint on fitness, pollen limitation, can be assessed experimentally by manually supplementing pollen receipt. We assembled a comparative dataset of pollen limitation using only studies that supplement pollen to all flowers produced over the plant's reproductive lifespan. Pre‐ and post‐pollination costs were estimated using the weight of flowers and fruits and estimates of fruit set. Consistent with expectations, we find self‐incompatible plants make greater pre‐pollination investments and experience greater pollen limitation. However, contrary to theoretical expectations, when variation due to self‐compatibility is accounted for by including self‐compatibility in the statistical model as a covariate, we find no support for the prediction that plants that invest more heavily in pre‐pollination costs are subject to greater pollen limitation. Strong within‐species, between‐population variation in the expression of pollen limitation makes the quantification of mean pollen limitation difficult. We urge plant ecologists to conduct more studies of pollen limitation using whole‐plant pollen supplementation to produce a richer comparative dataset that would support a more robust test of the balanced limitations hypothesis.

Background and Aims Sexual polymorphisms of flowers have traditionally been interpreted as devices that promote cross-pollination, but they may also represent adaptations for exploiting particular pollination niches in local environments. The cross-pollination function of enantiostyly, characterized by flowers having either left- or right-deflected styles, has been uncertain in some lineages, such as the Haemodoraceae, because the positioning of stamens and styles is not always completely reciprocal among morphs. Methods We examined the floral biology of populations of the poorly known species Barberetta aurea (Haemodoraceae) across its native range in South Africa to establish the general features of its enanatiostylous reproductive system and the agents and mechanism of pollen transfer. Results We confirmed that B. aurea has a system of dimorphic enantiostyly. Style morph ratios varied among populations sampled, but with an overall tendency to being equal. Crossing experiments demonstrated that B. aurea is fully self-compatible, that intra- and inter-morph crosses are equally fertile and that it is wholly dependent on pollinator visits for seed production. Pollination is mainly by syrphid flies that transfer the sticky pollen via their wings, which contact the anthers and stigma precisely as they hover during approach and feeding. The majority of syrphid fly visitors feed on a film of highly concentrated nectar situated at the base of ultraviolet-absorbent 'nectar guides'. Because one of the three stamens is deflected in the same direction as the style, we predicted a high likelihood of intra-morph pollination, and this was corroborated by patterns of transfer of coloured dye particles in cage experiments involving syrphid flies. Conclusions Barbaretta aurea exhibits dimorphic enantiostyly and, in contrast to most enantiostylous species, which are pollinated by bees, its flowers are specialized for pollination by syrphid flies. The lack of complete reciprocity of the enantiostylous arrangement of sexual organs facilitates both inter- and intra-morph pollen transfer on the wings of these flies. [ABSTRACT FROM AUTHOR]

Introduction: Monoecy is usually interpreted as an important evolutionary route of the plant sexual system from hermaphroditism to dioecy. This floral mechanism can effectively reduce self-interference during the reproductive process, and the services provided by pollinators may play an essential role in monoecious species; however, relevant research is still lacking. Thus, we aimed to determine whether monoecious plants could effectively avoid selfinterference and promote the evolution of monoecy under the service of pollinators. Methods: Here, we successfully performed manipulation experiments to test self-compatibility, pollinator behavior, and self-interference between male and female functions in Akebia trifoliata, a typical monoecious species. Results: We demonstrated that experimental self-pollination did not yield any fruit, and supplemental pollination significantly increased fruit set and fruit weight compared to natural pollination, suggesting that this species is completely selfincompatible and experiences strong pollen limitation. Simultaneous self- and cross-pollination and self-pollination prior to cross-pollination significantly reduced reproductive fitness, but self-pollination after cross-pollination did not, indicating self-interference in this plant. Moreover, both male flower probing preference and switching modes within inflorescences by pollinators successfully reinforced self-interference and were also responsible for decreasing reproductive fitness in A. trifoliata. Discussion: In summary, pollinator-mediated self-interference significantly reduced selfing, providing potential dynamics for the maintenance and evolution of monoecy. [ABSTRACT FROM AUTHOR]

Pollination is essential for the reproductive output of crops. Anthropogenic disturbance and global pollinator decline limit pollination success, reducing the quantity or quality of pollen. Relationships between the abundance of flower visitors and fruit production are often poorly understood. We aimed to (1) identify and quantify flower visitors in a mango orchard; (2) assess how much of the crop resulted from self- versus cross-pollination at increasing distances from a cross-pollen source in large, single-cultivar blocks of the cultivar Kensington Pride or the cultivar Calypso; and (3) determine how pollen parentage affected the size, colour, flavour attributes, and nutritional quality of fruit. Mango flowers were mostly visited by rhiniid flies and coccinellid beetles. Approximately 30% of the fruit were the result of cross-pollination, with the percentage significantly decreasing with an increasing distance from a cross-pollen source in the cultivar Calypso. Self-pollinated Calypso fruit were slightly larger and heavier, with higher acid and total polyphenol concentrations than cross-pollinated fruit. Our results showed higher-than-expected levels of cross-fertilisation among fruit, although self-pollen was likely more abundant than cross-pollen in the large orchard blocks. Our results suggest the preferential cross-fertilisation of flowers or the preferential retention of cross-fertilised fruitlets, both representing strategies for circumventing inbreeding depression. Growers should establish vegetated habitats to support pollinator populations and interplant cultivars more closely to maximise cross-pollen transfer. [ABSTRACT FROM AUTHOR]

Euonymus americanus is a common understory shrub in mesic deciduous forests of eastern North America. Its inconspicuous greenish-white flowers appear in late April and May and are regularly visited by several species of ants and, by night, a species of cockroach. Because the species is self-compatible, these pollinators need not move between plants to effect fertilization and fruit-set. Flowers last for three days and are strongly protandrous with little if any overlap of male and female function. Based on a survey of five years of reports on iNaturalist in Georgia, Prenolepis imparis is the most commonly observed ant, followed by Camponotus pennsylvanicus and Crematogaster lineolata, though Camponotus castaneus was more common than the latter two species at our study sites. Each of these species was found to carry many viable pollen grains, as was a species of cockroach (Cariblatta lutea). Exclusion of ants from flowers resulted in near-zero fruit-set. Nevertheless, addition of pollen increased fruit-set significantly over open-pollinated levels, indicating pollen limitation. The upper limit in terms of potential seeds per fruit is 30, representing six seeds in each of the five locules of a mature capsule, but the average number of seeds per capsule was only 12. Seed viability was high, exceeding 95%. [ABSTRACT FROM AUTHOR]

The species of the family Malpighiaceae are mainly diversified in the Neotropical Region as a consequence of a specialized pollination system. Due to the production of floral oils as a reward to pollinators, and their interaction with Centris, Epicharis (Centridini) and Monoeca (Tapinotaspidini) oil-collecting bee species in most neotropical species, many studies were focused on this interesting mutualistic interaction. However, a few have approached the reproductive biology of these species. The aim of this study was to gather all the existing information to date on the reproductive biology, megagametophyte development and apomixis of the Malpighiaceae species and analyze it together. We found 39 studies on the reproductive biology of 66 species, of which 47% are self-compatible, 33.3% self-incompatible, 18.2% have a mixed system, showing variable behavior among populations and 1.5% agamospermic species. We also found studies/reports on apomixis for eight species (three genera), polyembryony for six species (five genera) and on the development of megagametophyte for 14 species. We showed that our knowledge about the reproductive biology of Malpighiaceae species is scarce and fragmented, obtaining data for only 70–80 species (6–7% out of the total), most of which belonged to one population and/or few analyzed individuals. Further studies about the integral reproductive biology of these species that focus on the analysis of inter-population variations of the reproductive characters should be carried out to better understand how certain reproductive traits of Malpighiaceae species might have evolved and to provide valuable information on the mechanisms of population differentiation. [ABSTRACT FROM AUTHOR]

The evolution and expression of floral traits are responsive to selection pressure from biotic and abiotic factors. Although floral traits significantly vary among environments, the flower remains unchanged. We aimed to understand the adaptation of Epimedium chlorandrum of floral traits to a frequently nocturnally rainy and wet environments and the roles of floral traits in pollination and reproduction. We observed flowering phenology, measured floral characteristics including the number of pollen grains and ovules per flower, measured pollen viability and stigma receptivity, tested the volume and sugar concentration of nectar and conducted flower-visit observations in this species. Different pollination treatments were performed to characterize the breeding system. The inner sepals and highly curved longer spurs of E. chlorandrum jointly formed an umbrella that shielded the anthers and stigma from rain wash and prevented nectar dilution. Epimedium chlorandrum was visited by six species, while Bombus trifasciatus was the only effective pollinator and fed on the nectar. One flower secreted approximately 17.06 µL of nectar with a 29.19 g/100 mL sugar concentration, and the pollination efficiency of B. trifasciatus was positively associated with the nectar sugar concentration. The self- and open-pollination treatments resulted in fewer fertile seeds than the cross-pollination treatment. In contrast, the autonomous self-pollination treatment failed to yield fertile seeds. In summary, pollen limitation caused by harsh weather and pollinator shortage occurred during the pollination process of E. chlorandrum , which was partially alleviated by self-compatibility. [ABSTRACT FROM AUTHOR]

Reproductive systems and pollination modes (pollination by animals vs. wind) can switch within clades, and many species with an intermediate pollination mode (ambophily, pollination by animals and wind) exist. Here, we investigate the reproductive systems and pollination modes of two common Eurasian species from the Agrimonieae (Rosaceae) that occur in open habitats, Sanguisorba minor and Sanguisorba officinalis. Based on observations from literature, the flowers of both species are visited by insects, but due to flower morphology S. minor is commonly regarded as wind pollinated, while S. officinalis is classified as insect pollinated. By measuring floral traits, such as pollen grain and ovule number per flower, observing flower visitors in natural habitats as well as in the botanical gardens and conducting pollination experiments we found that the reproductive systems and pollination modes of the two species differ: Sanguisorba minor is commonly but infrequently visited by short‐tongued insects but is nevertheless exclusively wind pollinated. However, in contrast to most other wind‐pollinated species, S. minor is highly self‐compatible and even able to set seeds by autogamous selfing. Sanguisorba officinalis, on the other hand, is largely insect pollinated, but wind also contributes to seed set (⁓17% after insect exclusion). This species is able to set seeds by geitonogmous selfing but seed set is higher by outcrossing than by selfing. Thus, our study demonstrates another example of a plant species with small, open flowers arranged in large inflorescences that can be shown to be ambophilous. Further, the study will help to reconstruct the complex evolution of pollination modes in Agrimonieae (Rosaceae). [ABSTRACT FROM AUTHOR]

A transition to selfing can be beneficial when mating partners are scarce, for example, due to ploidy changes or at species range edges. Here, we explain how self-compatibility evolved in diploid Siberian Arabidopsis lyrata , and how it contributed to the establishment of allotetraploid Arabidopsis kamchatica. First, we provide chromosome-level genome assemblies for two self-fertilizing diploid A. lyrata accessions, one from North America and one from Siberia, including a fully assembled S -locus for the latter. We then propose a sequence of events leading to the loss of self-incompatibility in Siberian A. lyrata , date this independent transition to ∼90 Kya, and infer evolutionary relationships between Siberian and North American A. lyrata , showing an independent transition to selfing in Siberia. Finally, we provide evidence that this selfing Siberian A. lyrata lineage contributed to the formation of the allotetraploid A. kamchatica and propose that the selfing of the latter is mediated by the loss-of-function mutation in a dominant S -allele inherited from A. lyrata. [ABSTRACT FROM AUTHOR]

The reproductive strategies of alpine plants are often altered by environmental changes caused by changes in the spatial distribution of the gradient. However, few studies have investigated whether reproductive patterns of the same species vary with elevation. Three natural populations of Primula atrodentata , which are distributed in the eastern Himalayas and have a long flowering period, were selected along the elevation gradients in Shergyla Mountain, Tibet, China. Morph ratio investigation, floral trait measurement, pollinator observation and manipulated pollination experiments were conducted to explore the changes in self-compatibility and floral traits associated with the selfing syndrome along elevation gradients. We found that the breeding system of the S-morph is facultative outcrossing, and that of the L-morph is obligatory outcrossing. We further found that with increasing elevation, the number of pollen and ovules, anther–stigma distance, and inbreeding depression index first increased and then decreased, whereas the seeds per fruit and seed-setting rate under hand self-pollination, pollen limitation and self-incompatibility index tended to decrease first, but then increased. In addition, pollinator diversity and visiting frequency were the highest at the middle elevation (4050 population), which can better explain the nonlinear change in self-fertility with elevation. Our findings provide insights into the evolutionary pattern of self-compatibility in alpine plants along elevational gradients. [ABSTRACT FROM AUTHOR]

The sweet cherry plant (Prunus avium L.) is primarily self-incompatible, with so-called S-alleles responsible for the inability of flowers to be pollinated not only by their own pollen grains but also by pollen from other cherries having the same S-alleles. This characteristic has wide-ranging impacts on commercial growing, harvesting, and breeding. However, mutations in S-alleles as well as changes in the expression of M locus-encoded glutathione-S-transferase (MGST) can lead to complete or partial self-compatibility, simplifying orchard management and reducing possible crop losses. Knowledge of S-alleles is important for growers and breeders, but current determination methods are challenging, requiring several PCR runs. Here we present a system for the identification of multiple S-alleles and MGST promoter variants in one-tube PCR, with subsequent fragment analysis on a capillary genetic analyzer. The assay was shown to unequivocally determine three MGST alleles, 14 self-incompatible S-alleles, and all three known self-compatible S-alleles (S3′, S4′, S5′) in 55 combinations tested, and thus it is especially suitable for routine S-allele diagnostics and molecular marker-assisted breeding for self-compatible sweet cherries. In addition, we identified a previously unknown S-allele in the 'Techlovicka´ genotype (S54) and a new variant of the MGST promoter with an 8-bp deletion in the ´Kronio´ cultivar. [ABSTRACT FROM AUTHOR]

The relationships of interspecific compatibility and incompatibility in Solanum section Petota are complex. Inquiry into these relationships in tomato and its wild relatives has elucidated the pleiotropic and redundant function of S-RNase and HT which tandemly and independently mediate both interspecific and intraspecific pollen rejection. Our findings presented here are consistent with previous work conducted in Solanum section Lycopersicon showing that S-RNase plays a central role in interspecific pollen rejection. Statistical analyses also demonstrated that HT-B alone is not a significant factor in these pollinations; demonstrating the overlap in gene function between HT-A and HT-B, as HT-A, was present and functional in all genotypes used. We were not able to replicate the general absence of prezygotic stylar barriers observable in S. verrucosum, which has been attributed to the lack of S-RNase, indicating that other non-S-RNase factors play a significant role. We also demonstrated that Sli played no significant role in these interspecific pollinations, directly conflicting with previous research. It is possible that S. chacoense as a pollen donor is better able to bypass stylar barriers in 1EBN species such as S. pinnatisectum. Consequently, S. chacoense may be a valuable resource in accessing these 1EBN species regardless of Sli status. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia L.) is a monoecious species and although it exhibits self-compatibility, it presents incomplete overlap of pollen shed and female receptivity. Thus, cross-pollination is prerequisite for optimal fruit production. Cross-pollination can occur naturally by wind, insects, artificially, or by hand. Pollen has been recognized as one possible pathway for Xanthomonas arboricola pv. juglandis infection, a pathogenic bacterium responsible for walnut blight disease. Other than the well-known cultural and chemical control practices, artificial pollination technologies with the use of drones could be a successful tool for walnut blight disease management in orchards. Drones may carry pollen and release it over crops or mimic the actions of bees and other pollinators. Although this new pollination technology could be regarded as a promising tool, pollen germination and knowledge of pollen as a potential pathway for the dissemination of bacterial diseases remain crucial information for the development and production of aerial pollinator robots for walnut trees. Thus, our purpose was to describe a pollination model with fundamental components, including the identification of the “core” pollen microbiota, the use of drones for artificial pollination as a successful tool for managing walnut blight disease, specifying an appropriate flower pollination algorithm, design of an autonomous precision pollination robot, and minimizing the average errors of flower pollination algorithm parameters through machine learning and meta-heuristic algorithms.

Optimal fruit production from many tree crops relies on the transfer of cross-pollen between trees of different cultivars rather than the transfer of self-pollen between trees of the same cultivar. However, many orchards are established with wide blocks of single cultivars, which can result in high percentages of self-fertilised fruit and sub-optimal yield and quality. We aimed to determine whether outcrossing rates and yield of Hass avocado fruit decline with increasing distance from polliniser trees of cultivar Shepard and whether selfed fruit are smaller than outcrossed fruit. Outcrossing rates declined from 49% at six trees (40 m) from a block of Shepard trees to 30% at thirty trees (160 m) from a block of Shepard trees. Tree yield across this distance declined by 44% as a result of a 69% decline in the number of outcrossed fruit per tree, without a significant decline in the number of selfed fruit per tree. Outcrossed Hass fruit were 12% heavier than selfed Hass fruit, with 3% greater diameter and 5% greater length. The study results demonstrate the importance of interplanting Type B avocado pollinisers closely with Type A Hass trees to increase fruit yield and size.

Strawberry flowers are hermaphroditic and most cultivars are self-compatible, but strawberry plants can produce a mixture of fruit that have arisen from self-pollination and cross-pollination. We aimed to determine whether size, shape, color, taste attributes and shelf life differ between self-pollinated and cross-pollinated fruit competing on the same Redlands Joy strawberry plant. Experiments were repeated at three fertilizer levels to determine the consistency of responses across different levels of crop nutrition. Cross-pollinated fruits were 4.2%–7.5% heavier and 2.7%–5.0% longer than self-pollinated fruits, with the differences being greater at lower levels of nutrient supply. They were also darker or redder than self-pollinated fruits. Cross-pollinated fruits sometimes had lower °Brix (sugar) or lower acidity than self-pollinated fruits, with the effect on sugar:acid ratio depending on the nutrient level. The shelf life of cross-pollinated fruits was approximately 4 days longer than self-pollinated fruits on plants that received medium or high levels of fertilizer. The results suggest that pollen-parent effects on fruit size become evident when self- and cross-pollinated strawberry fruits compete for resources on the same plant, and that the expression of pollen-parent effects can be affected by the level of crop nutrition. [ABSTRACT FROM AUTHOR]

Pollination is essential for the reproductive output of crops. Anthropogenic disturbance and global pollinator decline limit pollination success, reducing the quantity or quality of pollen. Relationships between the abundance of flower visitors and fruit production are often poorly understood. We aimed to (1) identify and quantify flower visitors in a mango orchard; (2) assess how much of the crop resulted from self- versus cross-pollination at increasing distances from a cross-pollen source in large, single-cultivar blocks of the cultivar Kensington Pride or the cultivar Calypso; and (3) determine how pollen parentage affected the size, colour, flavour attributes, and nutritional quality of fruit. Mango flowers were mostly visited by rhiniid flies and coccinellid beetles. Approximately 30% of the fruit were the result of cross-pollination, with the percentage significantly decreasing with an increasing distance from a cross-pollen source in the cultivar Calypso. Self-pollinated Calypso fruit were slightly larger and heavier, with higher acid and total polyphenol concentrations than cross-pollinated fruit. Our results showed higher-than-expected levels of cross-fertilisation among fruit, although self-pollen was likely more abundant than cross-pollen in the large orchard blocks. Our results suggest the preferential cross-fertilisation of flowers or the preferential retention of cross-fertilised fruitlets, both representing strategies for circumventing inbreeding depression. Growers should establish vegetated habitats to support pollinator populations and interplant cultivars more closely to maximise cross-pollen transfer.

Plants have evolved various strategies to avoid inbreeding, but the mass flowering displayed by many plants predisposes them to within‐plant pollen movements and self‐pollination. Mistletoes often aggregate at multiple spatial scales. Their bird pollinators often visit several flowers of the same individual and of others on the same host tree. We hypothesized that hermaphroditic mistletoes have self‐incompatibility mechanisms that reduce or prevent selfing. Whether their spatial distribution, affected by host specificity, host distribution, and the behaviour of seed dispersers, influences their mating system and population genetic structure remains unclear. We studied how mating system and spatial distribution affect genetic structure in four populations of the host‐generalist mistletoe Dendrophthoe pentandra in southwestern China using microsatellite markers and progeny arrays. We also characterized the fine‐scale spatial genetic structure among 166 mistletoes from four host trees in one population. Prevalence and intensity of infection both appeared to vary among host species, strongly affecting the degree of aggregation. Host tree size had a strong effect on infection intensity. Surprisingly, manual pollination experiments indicated that D. pentandra is self‐compatible, but genetic analyses revealed that outcrossing rates were higher than expected in all four populations (MLTR tm 0.83–1.20, Bayesian tm 0.772–0.952). Spatial genetic structure was associated with distance between host trees but not at shorter scales (within hosts). Our results demonstrate that the combination of bird pollination, bird‐mediated seed dispersal, and post‐dispersal processes result in outcrossing and maintain relatively high diversity in the presence of biparental inbreeding, despite very high local densities and possible self‐compatibility. [ABSTRACT FROM AUTHOR]

In the production of blueberries, pollination is a key factor determining high quality yield. Problems with the process of pollination in blueberries occurs frequently. Lack of the effective pollination results in a lower yield and production of small fruits with low commercial value. The experiment described in this paper was carried out to test the effect of titanium organic complex (TOC) on the pollination and fertilization processes, seed formation, fruit setting and fruit development of blueberry in two consecutive years. The experiment consisted of two experimental factors: pollination type (self or open pollination) and application of TOC or lack of it. The presented study proves that TOC stimulates pollen adhesion and germination on the stigma, fruit setting, seed setting and fruit development. In self-pollinated flowers, the use of TOC increased the mass of each berry by 28% (in the first year) and 26% (in the second year), compared to non-treated plants. In open pollinated flowers, the application of TOC increased fruit mass by 38% (in the first year) and 29% (in the second year), compared to non-treated plants. Therefore, TOC may be treated as a substance stimulating the total fruit yield and mass of individual fruit. [ABSTRACT FROM AUTHOR]

Background and Aims Knowledge of the evolutionary processes responsible for the distribution of threatened and highly localized species is important for their conservation. Population genomics can provide insights into evolutionary processes to inform management practices, including the translocation of threatened plant species. In this study, we focus on a critically endangered eucalypt, Eucalyptus sp. Cattai, which is restricted to a 40-km2 area of Sydney, Australia, and is threatened by increased urbanization. Eucalyptus sp. Cattai has yet to be formally described in part due to its suspected hybrid origin. Here, we examined evolutionary processes and species boundaries in E. sp. Cattai to determine whether translocation was warranted. Methods We used genome-wide scans to investigate the evolutionary relationships of E. sp. Cattai with related species, and to assess levels of genetic health and admixture. Morphological trait and genomic data were obtained from seedlings of E. sp. Cattai propagated in a common garden to assess their genetic provenance and hybrid status. Key Results All analyses revealed that E. sp. Cattai was strongly supported as a distinct species. Genetic diversity varied across populations, and clonality was unexpectedly high. Interspecific hybridization was detected, and was more prevalent in seedlings compared to in situ adult plants, indicating that post-zygotic barriers may restrict the establishment of hybrids. Conclusions Multiple evolutionary processes (e.g. hybridization and clonality) can operate within one rare and restricted species. Insights regarding evolutionary processes from our study were used to assist with the translocation of genetically 'pure' and healthy ex situ seedlings to nearby suitable habitat. Our findings demonstrate that it is vital to provide an understanding of evolutionary relationships and processes with an examination of population genomics in the design and implementation of an effective translocation strategy. [ABSTRACT FROM AUTHOR]

In RBIP Holovousy originated new apricot cultivars ‘Telma’ and ‘Odeta’ during breeding program, both are registered for growing in the Czech Republic since 2021. Trees of both cultivars have spreading habitus and grow vigorously. Flowering time of ‘Telma’ cultivar is rather early in second week of April, fruit ripening time is medium late in third week of July and cultivar is typical with its high fruit set. Fruits have big size with average fruit length around 44 mm, fruit width 41 mm and fruit thickness 40 mm, Fruit weight is around 42 g. Fruits have high inner quality, and very good teste. Fruits of this cultivar are of higher tolerance to apricot scab (Stigmina carpophila). Cultivar ‘Odeta’ has medium late flowering time in second week of April and late ripening time in last week of July. Trees has medium fruit set volume. Fruits are of medium size with average fruit length around 43 mm, fruit width 39 mm and fruit thickness 36 mm. Fruit weight is around 37 g. Fruits have high inner quality and very good taste. Both cultivars are self-compatible and have low Monilia laxa susceptibility, low susceptibility for fruit cracking and skin burn. Both cultivars have good storability in cold storage. The origin of both cultivars was verified using a genotyping set of 19 SSR markers.

ABSTRACT The dependence of commercial crops on pollinators is closely related to their reproductive strategies and has direct impacts on production yields. Fruit production of Averrhoa carambola, the star fruit, is highly dependent on bee pollination. This distylous species may exhibit monomorphism associated with self-compatibility, a condition that may influence its degree of dependence on pollinators for fruit set. We evaluated the floral morphology and mating system of A. carambola and their relationships with pollinator dependence in an apparently pin-monomorphic orchard to address the following questions: Is the orchard indeed pin-monomorphic? Is the orchard self-compatible? Are pollination services sufficient to reach maximum productivity? Is fruit set related to the number of visits? We investigated floral morphometrics, mating system, and pollination following standard methods of plant reproduction research. The orchard exhibited pin-monomorphism and self-compatibility. Herkogamy strongly impaired spontaneous self-pollination, emphasizing the relevance of pollinators to crop yield. Considering that Apis mellifera was the only pollinator observed, and that the orchard showed pollen limitation, we recommend the implementation of pollinator management strategies. Additional studies will be needed to assess if the atypical distyly observed here occurs in other situations.

The study of interactions between plants and animals is important for detecting the degree of vulnerability of species under the current scenario of forest fragmentation. The genus Passiflora (Passifloraceae) is widely distributed in forest formations in Brazil with about 157 species. Here we studied the pollination biology of Passiflora morifolia, a native species of Brazil that is widely distributed in the American continent. Floral biology observations, controlled pollination tests and the recording of floral visitors were carried out in an area of natural occurrence, a fragment of Araucaria Moist Forest, located in the state of Paraná, Brazil. The results showed that the species is self-compatible, with flowers that open at night and remain open and receptive in the morning. The greatest volume of secreted nectar was observed at the beginning of anthesis, when the flower released an intense sweet odor and received visits from nocturnal and crepuscular bees. The bees Megommation insigne and Ptiloglossa willinki were the first visitors to the opened flowers and also the main pollinators. [ABSTRACT FROM AUTHOR]

The article presents two new almond cultivars obtained by the Centro de Edafologia y Biologia Aplicada del Segura (CEBAS)–Consejo Superior de Investigaciones Cientificas (CSIC) Almond Breeding Program: Florida and Alaska. Topics include examines both are self-compatible and soft-shelled with a kernel percentage higher than several percentage.

New apricot cultivar ´Etela´ originated from self-pollination of cultivar ´Harogem´ that has been realized RBIP Holovousy in 1996. This cultivar is registered for growing in the Czech Republic since 2021. It is self-compatible and precocious cultivar. Trees grow rather vigorously, has upright to spreading habitus and medium bearing. Fruits are attractive, medium size with smooth surface, of high quality and very good taste. The cultivar has generally good health condition, it is only slightly sensitive to apricot scab. This cultivar is recommended for the use in marginal regions of apricot growing.

The relationships of interspecific compatibility and incompatibility in Solanum section Petota are complex. Inquiry into these relationships in tomato and its wild relatives has elucidated the pleiotropic and redundant function of S-RNase and HT which tandemly and independently mediate both interspecific and intraspecific pollen rejection. Our findings presented here are consistent with previous work conducted in Solanum section Lycopersicon showing that S-RNase plays a central role in interspecific pollen rejection. Statistical analyses also demonstrated that HT-B alone is not a significant factor in these pollinations; demonstrating the overlap in gene function between HT-A and HT-B, as HT-A, was present and functional in all genotypes used. We were not able to replicate the general absence of prezygotic stylar barriers observable in S. verrucosum, which has been attributed to the lack of S-RNase, indicating that other non-S-RNase factors play a significant role. We also demonstrated that Sli played no significant role in these interspecific pollinations, directly conflicting with previous research. It is possible that S. chacoense as a pollen donor is better able to bypass stylar barriers in 1EBN species such as S. pinnatisectum. Consequently, S. chacoense may be a valuable resource in accessing these 1EBN species regardless of Sli status.

Boron plays a critical role in pollination and fertilization and can affect fruit set and yield. We applied 0 g, 15 g (manufacturer recommendation) or 30 g boron pre-flowering to Hass avocado trees to determine the effects on fruit set, fruitlet paternity, yield, fruit size, mineral nutrient concentrations and fatty acid composition. The boron applications did not significantly affect the initial fruit set at 3 or 6 weeks after peak anthesis or the proportions of self-pollinated fruitlets or mature fruit. Approximately 88–92% of the mature fruit were self-pollinated. However, applying 30 g boron per tree reduced the fruit set at 10 weeks after peak anthesis by 56% and the final yield by 25%. Attaining > 90% of the maximum yield was associated with foliar boron concentrations being below 104 mg/kg at 6 weeks after peak anthesis and between 39 and 68 mg/kg at 28 weeks after peak anthesis. Applying 15 g boron per tree increased the fruit mass by 5%, fruit diameter by 2%, flesh mass by 9%, flesh boron concentration by 55%, and the relative abundance of unsaturated fatty acids by 1% compared with control trees. Applying the recommended amount of boron provided a good yield of high-quality avocado fruit but applying boron at double the recommended rate reduced the yield. [ABSTRACT FROM AUTHOR]