Emasculated Flowers Research Articles

Selfing in epiphytic bromeliads compensates for the limited pollination services provided by nectarivorous bats in a neotropical montane forest.

Abstract. Plants with specialized pollination systems frequently exhibit adaptations for self-pollination, and this contradictory situation has been explained in terms of the reproductive assurance function of selfing. In the neotropics, several plant lineages rely on specialized vertebrate pollinators for sexual reproduction, including the highly diverse Bromeliaceae family, which also displays a propensity for selfing. Thus far, the scarce evidence on the role of selfing in bromeliads and in other neotropical plant groups is inconclusive. To provide insights into the evolution and persistence of self-fertilization in the breeding systems of Bromeliaceae, we studied four sympatric epiphytic species from the genus Werauhia (Tillandsioideae) in Costa Rica. We documented their floral biology, pollination ecology and breeding systems. We estimated the contribution of selfing by comparing the reproductive success between emasculated flowers requiring pollinator visits and un-manipulated flowers capable of selfing and exposed to open pollination across two flowering seasons. The studied species displayed specialized pollination by nectar-feeding bats as well as a high selfing ability (auto-fertility index values > 0.53), which was attained by a delayed selfing mechanism. Fruit set from natural cross-pollination was low (<26% in both years) and suggested limited pollinator visitation. In line with this, we found a very low bat visitation to flowers using video-camera recording, from 0 to 0.24 visits per plant per night. On the contrary, the contribution of selfing was comparatively significant since 54-80% of the fruit set from un-manipulated flowers can be attributed to autonomous self-pollination. We concluded that inadequate cross-pollination services diminished the reproductive success of the studied Werauhia, which was compensated for by a delayed selfing mechanism. The low negative effects of inbreeding on seed set and germination likely reinforce the persistence of selfing in this bromeliad group. These results suggest that selfing in bat-pollinated bromeliads may have evolved as a response to pollinator limitation.

Stigma receptivity and flower development stage during emasculation in tomato affect artificial hybridization

ABSTRACT Determination of appropriate stages of flower emasculation and flower development when self-pollination occurs in tomato (Solanum lycopersicum L.) flowers is important to increase the degree of success of cross pollination. The experiment was conducted from July 2015 to June 2017. Seven tomato varieties (as female parents) and 1 genotype (as pollen source) were evaluated. Stages of flower emasculation (3 levels) were: 1) emasculation of immature flowers (light yellow petal) (Stage I); 2) emasculation of mature flowers (dark yellow petal, and/or petal not opened) (Stage II); and 3) emasculation of mature flowers (dark yellow petal, and/or petal partially opened) (Stage III). Complete success of cross fertilization was for the interaction of Stage II (dark yellow petal, and/or petal not opened) flower emasculation with pollination of emasculated flower after 24 h. The lowest (1.8%) percent of success of cross fertilization was at stage I (light yellow petal) flower emasculation with pollination of emasculated flower within 12 h. The low range, 1.8–5.3% of success of cross fertilization was at flower stage III (dark yellow petal, and/or petal partially opened) emasculation with no pollination of emasculated flower, indicating occurrence of an accidental self-fertilization. Stage of flower development stage I (light yellow petal) and pollination of emasculated flowers after 48 h could give the optimum percent of success of cross fertilization and avoid accidental self-pollination.

Contrasting Pollination Strategies and Breeding Systems in Two Native Useful Cacti from Southern Brazil

Brazil is one of the centers of diversity of Cactaceae, yet studies addressing both pollination biology and the breeding system in Brazilian cacti are scarce. We herein present a detailed analysis of two native species with economic relevance: Cereus hildmannianus and Pereskia aculeata. The first species produce edible, sweet, spineless fruits and the second species produces leaves with high protein content. Pollination studies were undertaken through fieldwork observations in three localities of Rio Grande do Sul, Brazil, over two flowering seasons, totaling over 130 observation hours. Breeding systems were elucidated utilizing controlled pollinations. Cereus hildmannianus is solely pollinated by nectar-gathering species of Sphingidae hawk moths. In contrast, the flowers of P. aculeata are pollinated by predominantly native Hymenoptera but also by Coleoptera and Diptera, which gather pollen and/or nectar. Both cacti species are pollinator-dependent; neither intact nor emasculated flowers turn into fruit, yet whereas C. hildmannianus is self-incompatible, P. aculeata is fully self-compatible. In sum, C. hildmannianus is more restrictive and specialized regarding its pollination and breeding system, whereas P. aculeata is more generalist. Understanding the pollination needs of these species is a necessary starting point towards their conservation but also for their proper management and eventual domestication.

Protoplast Technology and Somatic Hybridisation in the Family Apiaceae.

Species of the family Apiaceae occupy a major market share but are hitherto dependent on open pollinated cultivars. This results in a lack of production uniformity and reduced quality that has fostered hybrid seed production. The difficulty in flower emasculation led breeders to use biotechnology approaches including somatic hybridization. We discuss the use of protoplast technology for the development of somatic hybrids, cybrids and in-vitro breeding of commercial traits such as CMS (cytoplasmic male sterility), GMS (genetic male sterility) and EGMS (environment-sensitive genic male sterility). The molecular mechanism(s) underlying CMS and its candidate genes are also discussed. Cybridization strategies based on enucleation (Gamma rays, X-rays and UV rays) and metabolically arresting protoplasts with chemicals such as iodoacetamide or iodoacetate are reviewed. Differential fluorescence staining of fused protoplast as routinely used can be replaced by new tagging approaches using non-toxic proteins. Here, we focused on the initial plant materials and tissue sources for protoplast isolation, the various digestion enzyme mixtures tested, and on the understanding of cell wall re-generation, all of which intervene in somatic hybrids regeneration. Although there are no alternatives to somatic hybridization, various approaches also discussed are emerging, viz., robotic platforms, artificial intelligence, in recent breeding programs for trait identification and selection.

Homology-based identification of candidate genes for male sterility editing in upland cotton (Gossypium hirsutum L.).

Upland cotton (Gossypium hirsutum L.) accounts for more than 90% of the world's cotton production, providing natural material for the textile and oilseed industries worldwide. One strategy for improving upland cotton yields is through increased adoption of hybrids; however, emasculation of cotton flowers is incredibly time-consuming and genetic sources of cotton male sterility are limited. Here we review the known biochemical modes of plant nuclear male sterility (NMS), often known as plant genetic male sterility (GMS), and characterized them into four groups: transcriptional regulation, splicing, fatty acid transport and processing, and sugar transport and processing. We have explored protein sequence homology from 30 GMS genes of three monocots (maize, rice, and wheat) and three dicots (Arabidopsis, soybean, and tomato). We have analyzed evolutionary relationships between monocot and dicot GMS genes to describe the relative similarity and relatedness of these genes identified. Five were lowly conserved to their source species, four unique to monocots, five unique to dicots, 14 highly conserved among all species, and two in the other category. Using this source, we have identified 23 potential candidate genes within the upland cotton genome for the development of new male sterile germplasm to be used in hybrid cotton breeding. Combining homology-based studies with genome editing may allow for the discovery and validation of GMS genes that previously had no diversity observed in cotton and may allow for development of a desirable male sterile mutant to be used in hybrid cotton production.

In Vivo Pollen Tube Growth and Evidence of Self-Pollination and Prefloral Anthesis in cv. Macabeo (Vitis vinifera L.)

Cultivar Macabeo is one of the most planted white grape varieties of northern Spain. A general agreement supports many Vitis vinifera cultivars possibly being self-fertile, although this seems to be a variety-dependent characteristic. No previous information about the mating system of cv. Macabeo was found. This study aimed to analyze its mating system and to compare the in vivo fertilization process with and without artificial cross-pollination. Two treatments were performed: emasculation and cross-pollination. The seed number was counted, and pollen tube growth was observed by microscopy. The results showed that cv. Macabeo is self-fertile and selfing probably occurs before the flower opens. Pollen was found over the stigma of flowers before capfall and ovule fertilization was observed even in emasculated flowers, which suggests that germination and pollen tube growth happened in a very early flower development stage. Cross-pollination increased the presence of the pollen tubes growing inside flowers but was not necessary for fruit set. Ovule fertilization was very fast as 24 h (h) were enough for pollen tubes to reach the end of stylar canals.

Identifying the Optimal Pollinizer for ‘Dermlali’ Olive Cultivar under Syrian Coast Conditions

ABSTRACT The research was conducted in the 2017 and 2019 seasons in two different orchards (Bouka and Sarabion), province of Latakia, Syria, in order to identify the optimal pollinizer for ‘Dermlali’ olive cultivar. Fruit set with/without emasculation of flowers after self-, open-, and cross-pollination was studied. ‘Khoderi,’ ‘Picholine Languedoc,’, and ‘Frantoio’ were used as pollinizers in Bouka, while ‘Picholine Languedoc’ and ‘Khoderi’ were used in Sarabion. Pistil abortion and the average number of flowers per inflorescence were also studied. Results showed that ‘Dermlali’ was characterized by a low number of flowers per inflorescence (12.6–11.4 in Bouka and 11.1–9.4 flower/inflorescence in Sarabion in 2017 and 2019, respectively), and low pistil abortion percentage (10.3–19.6% as an average of the 2017 and 2019 seasons in Bouka, and Sarabion, respectively). ‘Dermlali’ was highly self-incompatible in Bouka (ISI = 0–0.06), but partially self-incompatible in Sarabion (ISI = 0.42–0.50). In both study orchards, the highest final fruit set of ‘Dermlali’ was observed after cross-pollination with ‘Picholine Languedoc.’ Significantly lower final fruit sets of ‘Dermlali’ were observed after cross-pollination with ‘Frantoio’ in both orchards. Based on the recent-discovered diallelic self-incompatibility system in olive and compatibility relationships of ‘Dermlali’ (♀) with ‘Picholine Languedoc’ and ‘Frantoio,’ the S-genotype of ‘Dermlali’ would be S1S1. Overall results suggest that planting ‘Picholine Languedoc’ as pollinizer in ‘Dermlali’ olive orchards could significantly improve fruit set and yield.

A lever action hypothesis for pendulous hummingbird flowers: experimental evidence from a columbine.

Pendulous flowers (due to a flexible pedicel) are a common, convergent trait of hummingbird-pollinated flowers. However, the role of flexible pedicels remains uncertain despite several functional hypotheses. Here we present and test the 'lever action hypothesis': flexible pedicels allow pendulous flowers to move upwards from all sides, pushing the stigma and anthers against the underside of the feeding hummingbird regardless of which nectary is being visited. To test whether this lever action increased pollination success, we wired emasculated flowers of serpentine columbine, Aquilegia eximia, to prevent levering and compared pollination success of immobilized flowers with emasculated unwired and wire controls. Seed set was significantly lower in wire-immobilized flowers than unwired control and wire control flowers. Video analysis of visits to wire-immobilized and unwired flowers demonstrated that birds contacted the stigmas and anthers of immobilized flowers less often than those of flowers with flexible pedicels. We conclude that flexible pedicels permit the levering of reproductive structures onto a hovering bird. Hummingbirds, as uniquely large, hovering pollinators, differ from flies or bees which are too small to cause levering of flowers while hovering. Thus, flexible pedicels may be an adaptation to hummingbird pollination, in particular due to hummingbird size. We further speculate that this mechanism is effective only in radially symmetric flowers; in contrast, zygomorphic hummingbird-pollinated flowers are usually more or less horizontally oriented rather than having pendulous flowers and flexible pedicels.

Ovule senescence and unusual pollen tube growth in the ovary of sweet cherry as affected by pistilar genotype and temperature

The study of ovule senescence in the ovaries of four sweet cherry cultivars (‘Karina᾿, ‘Kordia᾿, ‘Regina᾿ and ‘Summit᾿) in the environmental conditions of West Serbia was carried out. Monitoring of ovaries was performed using the fluorescence microscopy method, on emasculated and pollinated flowers (cross-pollination variant), non-emasculated open-pollinated flowers (open pollination variant), and emasculated unpollinated flowers (unpollinated variant). In cross- and open pollination variants, the rate of unusual pollen tube growth in the ovary, fertilization percentage and fruit set were determined. The tendency in the appearance of fluorescence, as an indicator of ovule senescence, showed strong genotypic dependence ‒ it was the most and the least pronounced in the ovaries of ‘Kordia’ and ‘Regina’, respectively, in all the flower categories. Investigation of unusual pollen tube growth, fertilization percentage and fruit set, considered from the aspect of ovule senescence and cultivars’ behaviour as female (pollinated), pointed to their specific relations and complex dependence on the air temperature before and during the flowering. Flower emasculation and pollination also influenced ovule senescence, and this impact was unequal by genotypes, i.e. those having better ovule vitality in general, had also better ovule vitality in the conditions of emasculation, and pollination absence. The results imply different adaptation of cultivars to higher temperatures before and during the flowering, pointing to the further investigation related to the good adaptability of genotypes to air temperatures in reproductive sense, which is a basic indicator of good adaptability in general.

Seasonal Fluctuations in Pollen Production and Viability in Eggplant and the Quality of Seed-Containing and Seedless (Auxin-Set) Fruits

This study investigates the influence of climate on pollen production and viability of two eggplant cultivars cultivated throughout the year in a greenhouse within the Mediterranean basin and the efficacy of auxin application to produce marketable fruit under unfavourable climatic conditions. The pollen yield per flower of both cultivars was highest during November and lowest in January and July, when air temperatures were lowest and highest, respectively. Pollen germination and tube growth in vitro were highest in spring and autumn irrespective of the cultivar. Under low night temperatures (< 15 °C), normal fruit set was not possible due to inadequate pollen production and viability, whereas the application of β-naphthoxyacetic acid to emasculated flowers enabled parthenocarpic/seedless fruit development. When pollen was not a limiting factor, both seed-containing and parthenocarpic fruit were produced. Initially, parthenocarpic fruit developed more rapidly than fruit set by pollination. However, by market maturity, both fruit types of either cultivar were similar in mean weight, size, and shape. Moreover, the external colour of seedless and seed-containing fruit was similar, whereas the percent dry matter of the seedless fruit tended to be lower. We conclude that because at times of excessively low or high temperatures pollen production and viability are adversely affected, fruit set requires assistance. In eggplant, application of the fruit-setting compound β-naphthoxyacetic acid results in the setting of seedless fruit that are similar in size and appearance to those set by natural pollination.

Inducement and identification of chromosome introgression and translocation of Gossypium australe on Gossypium hirsutum

BackgroundWe previously reported the development of a set of Gossypium hirsutum-G. australe alien chromosome addition lines. Naturally, however, G. hirsutum-G. australe chromosome exchanges were very limited, impeding the stable transference of useful genes from G. australe (G2G2 genome) into the most cultivated cotton, G. hirsutum (AADD).ResultsIn the present report, the pollen from a pentaploid (2n = AADDG2) of G. hirsutum-G. australe was irradiated with seven different doses ranging from 10 to 40 Grays and used to pollinate emasculated flowers of G. hirsutum over three consecutive years. Irradiation greatly increased the genetic recombination rates of the G. hirsutum and G. australe chromosomes and a total of 107 chromosome introgression individuals in 192 GISH-negative (with no GISH signal on chromosome) survived individuals, 11 chromosome translocation individuals (containing 12 chromosome translocation events) and 67 chromosome addition individuals were obtained in 70 GISH-positive (with GISH signal(s) on chromosome(s)) survived individuals, which are invaluable for mining desirable genes from G. australe. Multicolor genomic in situ hybridization results showed that there were three types of translocation, whole arm translocation, large alien segment translocation and small alien segment translocation, and that all translocations occurred between the G2-genome and the A-subgenome chromosomes in G. hirsutum. We also found that higher doses induced much higher rates of chromosome variation but also greatly lowered the seed viability and seedling survivability.ConclusionsIrradiation has been successfully employed to induce chromosome introgressions and chromosome translocations and promote chromosome exchanges between cultivated and wild species. In addition, by balancing the rates of chromosome introgression and translocation to those of seed set, seed germination, and seedling rates in the M1 generation, we conclude that the dosage of 20 Grays is the most suitable. The established methodology may guide the utilization of the tertiary gene pool of Gossypium species such as G. australe in cotton breeding in the future.

Columbine pollination success not determined by a proteinaceous reward to hummingbird pollinators

Plants provision pollinators with a variety of nutritious or otherwise beneficial rewards. Hummingbirds (primarily Calypte anna) pollinate the columbine Aquilegia eximia. In addition to drinking nectar, they glean entrapped insects from its sticky surfaces. To test the hypothesis that this insect carrion, an abundant and easily-collected protein source, serves as a provision to the pollinator and increases pollination I experimentally manipulated this reward and measured pollination success. I set up three treatments - an insect carrion addition, carrion removal, and an unmanipulated control - on small patches of the plant in each of five populations of A. eximia. Pollination success, measured by seed set in emasculated flowers, was unaffected by carrion level. Pollination success positively correlated with average floral display in each patch; this suggests that local nectar reward in an area is more important than this proteinaceous reward in determining pollination success. Stickiness in this system may function as an effective exclusion mechanism for smaller-bodied pollinators. While this study did not demonstrate that captured insects increased reproductive success of this columbine, this interaction (and pollinator exclusion) may play a role in other hummingbird-plant interactions, as hummingbird pollination and insect-entrapment occur together in at least nine species of six plant families.

Effect of Resource Reallocation on Pollen Limitation and Reproductive Assurance of Apocynum venetum L. in an Arid Region

&lt;p&gt;Pollen limitation is considered to be a strong force driving the evolution of reproductive strategies in flowering plants. However, resource reallocation may occur among seeds because of variation in the quantity or quality of pollen received. We performed single-flower and whole-plant pollen supplementation and emasculation of flowers of &lt;em&gt;Apocynum venetum&lt;/em&gt; L. to estimate pollen limitation and reproductive assurance. In addition, we calculated the visiting patterns of the pollinators, frequency of pollinators to estimate the effect of pollinator activity and further on the reproductive success of &lt;em&gt;A. venetum&lt;/em&gt;. Our results indicated estimates from single-flower manipulations were not biased, closely resembling those from whole-plant manipulations. We found&lt;em&gt; Apis mellifera&lt;/em&gt; was the dominant pollinator during the pollination process. In addition, insect pollination played a more important role in the outcrossing system, which could explain the differences in reproductive success. Our results also showed that autonomous self-pollination eliminates pollen limitation and provides reproductive assurance.&lt;/p&gt;

Floral and reproductive biology of Vaccinium meridionale (Ericaceae) in the Eastern Andes of Colombia.

&lt;p class="Standard"&gt;&lt;em&gt;Vaccinium meridionale&lt;/em&gt; es una planta silvestre productora de frutos comestibles en las áreas montañosas del norte de Suramérica. Sin embargo, no hay información suficiente sobre su sistema reproductivo, lo cual es fundamental para su manejo y conservación dado que sus frutos son extraídos de forma no sostenible y hay un creciente interés en establecer la especie como cultivo. Los objetivos de este trabajo fueron estudiar la biología floral y reproductiva de &lt;em&gt;V. meridionale &lt;/em&gt;en condiciones naturales y analizar la importancia de los polinizadores en su reproducción. Para esto se realizaron observaciones y experimentos para describir su morfología y fenología floral, viabilidad de polen, receptividad de estigma, relación polen óvulo y producción de néctar. Para estudiar su sistema reproductivo se realizaron experimentos de emasculación, exclusión de polinizadores y polinización manual (autopolinización y polinización cruzada). El estudio se realizó con dos poblaciones silvestres de &lt;em&gt;V. meridionale&lt;/em&gt; ubicadas en los departamentos de Cundinamarca y Boyacá, en la Cordillera Oriental de Colombia. Se encontró que aunque las flores tienen anteras poricidas la liberación del polen se da fácilmente sin vibración. &lt;em&gt;V. meridionale&lt;/em&gt; presenta un gran despliegue y larga longevidad floral y hay un sesgo en la producción de néctar hacia la función femenina. Se estimó una relación polen/óvulo de 571±133, lo que clasifica a la especie como xenógama facultativa. Este resultado coincidió con los experimentos de polinización ya que en las dos poblaciones estudiadas las plantas produjeron frutos por agamospermia, autogamia y xenogamia. No obstante, se observó una fuerte depresión por endogamia manifestada en altas tasas de aborto de frutos producidos por autogamia a diferencia de los frutos provenientes de polinización cruzada que fueron retenidos por la planta desde su formación. Los rasgos florales presentados por la especie se consideran mecanismos para favorecer un gremio más diverso de visitantes florales que sólo los insectos capaces de polinización por vibración. Además, estos rasgos florales pueden aumentar la probabilidad de polinización y disminuir la geitonogamia. Igualmente la depresión por endogamia sugiere que la especie busca mantener el entrecruzamiento como su principal estrategia reproductiva. Por lo tanto, los polinizadores, en particular las abejas son fundamentales para la reproducción de &lt;em&gt;V. meridionale &lt;/em&gt;y en consecuencia su conservación es esencial para mantener la variabilidad genética y oferta de frutos de esta especie.&lt;/p&gt;&lt;p class="Standard"&gt; &lt;/p&gt;

Floral biology of indigenous pummelo genotypes

Flower morphology and bud development of pummelo accessions CG-1, CG-18 and CG-151 were studied at the Pummelo Orchard of Regional Agricultural Research Station, BARI, Akbarpur, Moulvibazar and the Horticulture Laboratory of Bangabandhu Sheikh Mujibur Rahman Agricultural University during 2008-2009. Pummelo flowers were bisexual, bore singly on leaf axils or in clusters with or without leaf on stem in all accessions, and colour were white. Calyx diameter varied from 0.94 in CG-1 to 1.02 in CG-18. Number of petals per flower ranged from 4.0 to 4.5. Anthers were yellow in colour and only CG- 151 produced few rudimentary styles. Diameter of stigma varied from 0.39 mm to 0.49 mm. Number of locules per ovary was in between 14.6 to16.0 and number of ovules per locules varied from 4.0 to 9.0. Stages of floral bud development from initiation to anthesis were divided into 9 distinct stages. In pummelo, a total of 27.7 to 31.2 days were required from a bud initiation to reach its fully developed stage. Suitable time for emasculation of pummelo flowers was found within 26 days from flower bud initiation. Between 3:00am to 5:00am, about 76% flowers were found to be opened and between 4:00pm to 5:00pm in all the three accessions, dehiscence of pollens was recorded. Abscission of stamen, petal and style started after 50.8, 76.4 and 162.3 hrs and completed after 128.4, 137.9 and 228.3 hrs of anthesis, respectively.Bangladesh J. Agril. Res. 40(2): 177-188, June 2015

Ethylene suppresses tomato (Solanum lycopersicum) fruit set through modification of gibberellin metabolism.

Fruit set in angiosperms marks the transition from flowering to fruit production and a commitment to seed dispersal. Studies with Solanum lycopersicum (tomato) fruit have shown that pollination and subsequent fertilization induce the biosynthesis of several hormones, including auxin and gibberellins (GAs), which stimulate fruit set. Circumstantial evidence suggests that the gaseous hormone ethylene may also influence fruit set, but this has yet to be substantiated with molecular or mechanistic data. Here, we examined fruit set at the biochemical and genetic levels, using hormone and inhibitor treatments, and mutants that affect auxin or ethylene signaling. The expression of system-1 ethylene biosynthetic genes and the production of ethylene decreased during pollination-dependent fruit set in wild-type tomato and during pollination-independent fruit set in the auxin hypersensitive mutant iaa9-3. Blocking ethylene perception in emasculated flowers, using either the ethylene-insensitive Sletr1-1 mutation or 1-methylcyclopropene (1-MCP), resulted in elongated parthenocarpic fruit and increased cell expansion, whereas simultaneous treatment with the GA biosynthesis inhibitor paclobutrazol (PAC) inhibited parthenocarpy. Additionally, the application of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) to pollinated ovaries reduced fruit set. Furthermore, Sletr1-1 parthenocarpic fruits did not exhibit increased auxin accumulation, but rather had elevated levels of bioactive GAs, most likely reflecting an increase in transcripts encoding the GA-biosynthetic enzyme SlGA20ox3, as well as a reduction in the levels of transcripts encoding the GA-inactivating enzymes SlGA2ox4 and SlGA2ox5. Taken together, our results suggest that ethylene plays a role in tomato fruit set by suppressing GA metabolism.

INTRASPECIFIC CROSS-COMPATIBILITY IN ORNAMENTAL PEPPER

The production of Capsicum for ornamental purposes in Brazil has increased in recent years. To support the activities of this promising market, it is essential to develop new cultivars by hybridization. The knowledge of cross compatibility is also important in plant evolution research as it provides new genetic combinations and promotes speciation. There are few records of intraspecific compatibility studies in Capsicum. The objective of this work was to evaluate and describe cross compatibilities in accessions of Capsicum annuum. This experiment was carried out in a greenhouse at Universidade Federal da Paraiba (UFPB). Nine lines of Capsicum annuum (UFPB 45, UFV 46, UFPB 132, UFPB 134, UFPB 390, UFPB 392, UFV443, UFV 448, and UFV 449), belonging to the Horticultural Germplasm Bank of UFPB and Universidade Federal de ViA§osa (UFV), were chosen for the study based on their broad genetic background and phenotypic diversity. They were crossed according to a full diallel schedule. The manual crosses were made at pre-anthesis stage in emasculated flowers. The percentage of fruit set was estimated as the number of fruits formed divided by the total crosses made and varied from 20 to 100%. The intraspecific compatibility varied both with the direction of the crossings and the parents used in the crossing, showing intraspecific incompatibility exists and depends on the genotypes. Parthenocarpic fruits and fruits with very few seeds were observed. Some fruits showed apocarpy. Some crosses showed anthocyanin in the placenta tissues. The knowledge of the intraspecific compatibility as well as of the direction of crossing is extremely important for success in hybrid breeding programs.

A Crossing Method for Quinoa

As sustainable production of quinoa (Chenopodium quinoa Willd.) increases and its geographic range of cultivation expands, quinoa breeding will allow use of the crop’s wide genetic diversity for cultivar improvement and for adaptation to new agroecosystems and climactic regimes. Such breeding work will require a reliable technique for crossing quinoa plants using hand emasculation. The technique described herein focuses on the isolation of small flower clusters produced low on the plant, emasculation of male flowers, and subsequent pairing of the emasculated female parent with a male parent undergoing anthesis. Various traits, such as plant color, seed color, and axil pigmentation can be used to confirm the successful production of F1 plants. The manual hybridization technology provides a significant advantage over pairing plants and relying on chance cross-pollination, and has been successfully used to generate crosses between quinoa cultivars, as well as interspecific crosses between quinoa and Chenopodium berlandieri. This technology will help pave the way for the introduction and sustainable expansion of quinoa on a global scale across a wide range of target environments and diverse farming systems.

Effect of morphactin IT 3456 (methyl-2-chloro-9-hydroxyfluorene-(9)-carboxylate) on parthenocarpic fruit development of tomatoes

It was found that parthenocarpy could be induced by morphactin IT 3456 (0.5 and 1 ppm) in prior emasculated flowers, those left to free-pollination and even flowers pollinated with the pollen of control plants (New Yorker). When morphactin IT 3456 in 0.5 and 1 ppm concentrations was used 88% and 100% of parthenocarpy was noted in the greenhouse, respectively (Earliest of All). The higest percentage of parthenocarpy in the total number of fruits in the field was recorded in the 'New Yorker' variety. The lowest percentage of parthenocarpy was observed in the variety 903. The symptoms of the destructive influence of morphactin IT 3456 (0.5 and 1 ppm) on plant development were noted, but they were stronger in the greenhouse than in the field.

Induction of gibberellin 20-oxidases and repression of gibberellin 2β-oxidases in unfertilized ovaries of entire tomato mutant, leads to accumulation of active gibberellins and parthenocarpic fruit formation

In tomato (Solanum lycopersicum L.), auxin and gibberellins (GAs) cross-talk plays an important role during fruit-set. The entire tomato mutant has been previously reported to carry a deletion in the coding region of the SlIAA9 gene, a member of the auxin signal repressor family Aux/IAA. In this paper, we examined the role of ENTIRE gene in controlling GAs metabolism and directing spontaneous fruit initiation and early ovary growth. It was shown that, similarly to pollinated fruits, facultative parthenocarpy in entire depends on active GA metabolism, since fruit growth is suppressed when GA biosynthesis is blocked. Analysis of endogenous GAs during the first 10 days after flower emasculation revealed that entire fruits accumulated higher amounts of active GAs (GA1 and GA3) in comparison to wild type pollinated fruits, suggesting that a different GA homeostasis regulation occurs. Transcript analysis of the main GA biosynthesis genes showed that differently from unpollinated and non parthenocarpic wild type ovaries, in entire active GA flux modulation is regulated by the activation of SlGA20ox1 and SlGA20ox2 and also by a marked reduction of GA catabolism (reduced transcription of GA 2β-oxidase genes) during the early fruit expansion phase.