Early Flowering Research Articles

Flowering time regulator qFT13-3 involved in soybean adaptation to high latitudes.

Soybean is a short-day plant that typically flowers earlier when exposed to short-day conditions. However, the identification of genes associated with earlier flowering time but without a yield penalty is rare. In this study, we conducted genome-wide association studies (GWAS) using two re-sequencing datasets that included 113 wild soybeans (G. soja) and 1192 cultivated soybeans (G. max), respectively, and simultaneously identified a candidate flowering gene, qFT13-3, which encodes a protein homologous to the pseudo-response regulator (PRR) transcription factor. We identified four major haplotypes of qFT13-3 in the natural population, with haplotype H4 (qFT13-3H4) being lost during domestication, while qFT13-3H1 underwent natural and artificial selection, increasing in proportion from 4.5% in G. soja to 43.8% in landrace and to 81.9% in improve cultivars. Notably, most cultivars harbouring qFT13-3H1 were located in high-latitude regions. Knockout of qFT13-3 accelerated flowering and maturity time under long-day conditions, indicating that qFT13-3 functions as a flowering inhibitor. Our results also showed that qFT13-3 directly downregulates the expression of GmELF3b-2 which is a component of the circadian clock evening complex. Field trials revealed that the qft13-3 mutants shorten the maturity period by 11 days without a concomitant penalty on yield. Collectively, qFT13-3 can be utilized for the breeding of high-yield cultivars with a short maturity time suitable for high latitudes.

SpeedFlower: a comprehensive speed breeding protocol for indica and japonica rice.

To increase rice yields and feed billions of people, it is essential to enhance genetic gains. However, the development of new varieties is hindered by longer generation times and seasonal constraints. To address these limitations, a speed breeding facility has been established and a robust speed breeding protocol, SpeedFlower is developed that allows growing 4-5 generations of indica and/or japonica rice in a year. Our findings reveal that a high red-to-blue (2R > 1B) spectrum ratio, followed by green, yellow and far-red (FR) light, along with a 24-h long day (LD) photoperiod for the initial 15 days of the vegetative phase, facilitated early flowering. This is further enhanced by 10-h short day (SD) photoperiod in the later stage and day and night temperatures of 32/30 °C, along with 65% humidity facilitated early flowering ranging from 52 to 60 days at high light intensity (800 μmol m-2 s-1). Additionally, the use of prematurely harvested seeds and gibberellic acid treatment reduced the maturity duration by 50%. Further, SpeedFlower was validated on a diverse subset of 198 rice accessions from 3K RGP panel encompassing all 12 distinct groups of Oryza sativa L. classes. Our results confirmed that using SpeedFlower one generation can be achieved within 58-71 days resulting in 5.1-6.3 generations per year across the 12 sub-groups. This breakthrough enables us to enhance genetic gain, which could feed half of the world's population dependent on rice.

Bazı Ekmeklik ve Makarnalık Buğday Çeşitlerinde Sarı Pas Hastalığının Fenolojik Dönemlere göre Hastalık-Verim İlişkisinin Çok Bantlı (Hiperspektral) Veriler Kullanılarak Araştırılması

The aim of this study was to evaluate the severity of yellow rust in different phenological periods by 
 subjecting bread (Bayraktar 2000, Demir 2000, Eser and Kenanbey) and durum (Çeşit-1252, Eminbey, Kızıltan 91 and Mirzabey 2000) wheat varieties to different spore doses (0%, 25%, 50% and 100%) under controlled epidemic conditions. The research was conducted in Yenimahalle, Ankara, Turkey during the 2018-2019 growing season. In the study, the morphological changes in yellow rust severity were determined at different phenological developmental stages of the test materials with the reflectance values obtained by using handheld spectroradiometer in different spore dose applications during the period from tillering to stalk emergence. These reflectance values were converted into vegetation index values expressed by mathematical formulae and used in determining yield estimates. Considering the results obtained, it was determined that the spectral indices calculated especially in the early flowering period (25 May 2019, Feekes 10.5.1) were effective in yield estimation for all bread varieties except Kenanbey variety (15 June 2019, Feekes 10.5.4). It was determined that the spectral band region of 25 May 2019 (Feekes 10.5.1), which includes all indices determined to predict yield in all bread and durum varieties and which is the beginning of flowering, was effective. In grain yield estimation, it was determined that there was a decrease in the correlation values of the spectral indices starting from the early flowering period (Feekes 10.5.1) towards the grain setting period (Feekes 10.5.3) and milk maturity period 
 (Feekes 10.5.4). When the correlations between these index values and yield values were examined, it was 
 determined that prominent phenological periods and high correlation indices could be calculated for these periods. Nowadays, with the use of optical sensor technology instead of traditional disease surveillance methods, the way has paved the way for the development of new approaches for early, fast and accurate yield estimation as a result of the verification of images taken by unmanned aerial vehicles on which multispectral and hyperspectral cameras are located with ground data using artificial intelligence and deep learning techniques.

Arabidopsis SEC13B Interacts with Suppressor of Frigida 4 to Repress Flowering.

SECRETORY13 (SEC13) is an essential member of the coat protein complex II (COPII), which was reported to mediate vesicular-specific transport from the endoplasmic reticulum (ER) to the Golgi apparatus and plays a crucial role in early secretory pathways. In Arabidopsis, there are two homologous proteins of SEC13: SEC13A and SEC13B. SUPPRESSOR OF FRIGIDA 4 (SUF4) encodes a C2H2-type zinc finger protein that inhibits flowering by transcriptionally activating the FLOWERING LOCUS C (FLC) through the FRIGIDA (FRI) pathway in Arabidopsis. However, it remains unclear whether SEC13 proteins are involved in Arabidopsis flowering. In this study, we first identified that the sec13b mutant exhibited early flowering under both long-day and short-day conditions. Quantitative real-time PCR (qRT-PCR) analysis showed that both SEC13A and SEC13B were expressed in all the checked tissues, and transient expression assays indicated that SEC13A and SEC13B were localized not only in the ER but also in the nucleus. Then, we identified that SEC13A and SEC13B could interact with SUF4 in vitro and in vivo. Interestingly, both sec13b and suf4 single mutants flowered earlier than the wild type (Col-0), whereas the sec13b suf4 double mutant flowered even earlier than all the others. In addition, the expression of flowering inhibitor FLC was down-regulated, and the expressions of flowering activator FLOWERING LOCUS T (FT), CONSTANS (CO), and SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1) were up-regulated in sec13b, suf4, and sec13b suf4 mutants, compared with Col-0. Taken together, our results indicated that SEC13B interacted with SUF4, and they may co-regulate the same genes in flowering-regulation pathways. These results also suggested that the COPII component could function in flowering in Arabidopsis.

Genomic insight into variations associated with flowering-time and early-maturity in pigeonpea mutant TAT-10 and its wild type parent T21

Pigeonpea [Cajanus cajan (L.) Millspaugh] is an important grain legume crop with a broad range of 90 to 300 days for maturity. To identify the genomic variations associated with the early maturity, we conducted whole-genome resequencing of an early-maturing pigeonpea mutant TAT-10 and its wild type parent T21. A total of 135.67 and 146.34 million sequencing reads were generated for T21 and TAT-10, respectively. From this resequencing data, 1,397,178 and 1,419,904 SNPs, 276,741 and 292,347 InDels, and 87,583 and 92,903 SVs were identified in T21 and TAT-10, respectively. We identified 203 genes in the pigeonpea genome that are homologs of flowering-related genes in Arabidopsis and found 791 genomic variations unique to TAT-10 linked to 94 flowering-related genes. We identified three candidate genes for early maturity in TAT-10; Suppressor of FRI 4 (SUF4), Early Flowering In Short Days (EFS), and Probable Lysine-Specific Demethylase ELF6. The variations in ELF6 were predicted to be possibly damaging and the expression profiles of EFS and ELF6 also supported their probable role during early flowering in TAT-10. The present study has generated information on genomic variations associated with candidate genes for early maturity, which can be further studied and exploited for developing the early-maturing pigeonpea cultivars.

EFFECTIVENESS PRUNING AND PLANTING MEDIA ON THE MORPHOLOGY AND RESULTS OF FLOATING RED CHILIES

Horticultural commodities hold significant economic potential in Indonesia, particularly red chilies, which serve various purposes such as a spicy,traditional spicy, and industrial raw material. This research aims to assess the impact of shoot pruning and planting media composition on the morphology and yield of red chili plants. The study employed a Randomized Factorial Group Desugn (RAKF) with two main treatments : shoot pruning and planting medium composition. Results indicate that pruning shoots at 35 days after planting (P4) enhances the cultivation of red chili plants, as evidenced by improved plant height, earlier flowering, and increased root length. Furthermore, a planting medium composed of soil, cow dung compost, and 2:1:1 husk charcoal (M4) proves to be more beneficial for red chili yield, demonstrated by higher plant height, stem diameter, and root length.

Preservation and study of natural species from the genus Iris at the Subtropical Scientific Centre of the Russian Academy of Sciences

Solving the problems of preservation and rational use of plant genetic diversity is one of the main tasks for botanical gardens and scientific institutions working in this field. In the Subtropical Scientific Centre of the Russian Academy of Sciences, the collection of natural species of the genus Iris has been formed since 2000s. The paper presents research results on the following 11 species: Iris colchica Kem.-Nath., I. ensata Thunb., I. japonica Thunb, I. orientalis Mill.,I. notha M. Bieb, I. pallida Lam., I. pseudacorus L., I. pseudonotha Galushko, I. sibirica L., I. spuria L., I. unguicularis Poir. Most of the species are rare (6), rare and endemic (2). As a result of the studies conducted in 2020-2022, flowering terms for the irises species in collection have been established in the humid subtropics of Russia and 4 groups have been recorded. The first group with the earliest flowering (April, early May) includes I. japonica, I. sibirica. Average flowering terms (from mid-late May) are recorded for I. orientalis, I. colchica, I. pallida, I. pseudacorus. Late flowering terms (from late May - early June) are recorded for I. notha, I. pseudonotha, I. ensata. Late autumn-early winter periods - for I. unguicularis.

The influence of the weather conditions on the flowering time of crocuses from the collection of the Subtropical Scientific Center of the Russian Academy of Sciences

Iridaceae is a large family of herbaceous plants with numerous species and cultivars, diverse in the habitus and structure of aboveground and underground organs, colour and shape of the flower, as well as in terms and duration of phenological phases. The earliest flowering is specific for representatives of the genus Crocus. The purposeful formation and study of genetic collections of ornamental crops, including Crocus, was started by Federal Research Centre the Subtropical Scientific Centre of the Russian Academy of Sciences in the 1960s. A large number of cultivars have been introduced and studied. The aim of the work is to study the influence of the weather conditions on the flowering terms of crocuses in the humid Russian subtropics on the Black Sea coast of Krasnodar Territory. This unique region belongs to a Mediterranean-type climate with relatively warm winters. The work was carried out in 2021-2023 according to the methods generally accepted in the introduction, as well as those being finalized by the Centre. Mathematical processing was performed in the Microsoft Office Excel 2007 program. The objects of research are 19 crocus cultivars from the bioresource collection (FRC SSC of RAS), including Crocus vernus - 7; C. chrysanthus - 4; C. tommasinianus - 4, 1 each C. flavus, C. biflorus, C. sublimis, C. olivieri. In the course of the work carried out, it has been found that climatic conditions of the humid Russian subtropics make it possible to successfully implement introduction studies on Crocus cultivars.

Effects of Bio-Amendment of Coconut Dust with Empty Fruit Bunch Compost on the Efficacy of Mycorrhizae Under Deficit Fertigation

It has been known that the application of beneficial fungi and compost, has a favourable effect on easing water deficiency stress in plants, hence helping to boost agricultural activities in times of climate uncertainty. In this study, the influence of arbuscular mycorrhizal fungi (AMF) in combination with oil palm empty fruit bunch compost (EFB) on the growth, yield, and physiology of chilli under deficit fertigation was investigated. Throughout the study, five-week-old chilli seedlings were fertigated daily with 100% and 60% of daily evapotranspiration (ET) readings. Three days after transplanting, 10g of sandy soil containing roughly 120-150 mycorrhizal spores was applied to the root zone. Physiological data such as real-time photosynthesis and stomatal conductance were measured at vegetative, early flowering, fruit setting, and maturity or harvesting stages. Meanwhile, yield and morphological measurements were recorded at the end of the study. It was discovered that the addition of EFB to the coconut coir dust media enhanced the beneficial effects of AMF on all parameters including total biomass, chlorophyll fluorescence Fv/Fm, total chlorophylls, photosynthesis rate and stomatal conductance regardless of fertigation levels. The study also revealed that AMF inoculation alone was less effective than non-inoculation + EFB. In conclusion, it is suggested that incorporation of AMF and EFB compost positively affect the yield, growth and physiology of chilli under deficit fertigation.

Development of Mungbean Genotypes for Shattering Tolerance and Correlation Analysis with Biochemical and Morphological Factors Governing Pre Harvest Sprouting

Background: Most of the mungbean genotypes are prone to shattering. The indeterminate flowering habit of this crop leads to a spread of flowering and pod maturity on a single plant over the entire reproductive phase. Consequently, pods which develop at the earliest flower may shatter prior to 100% pod maturity. Sometimes losses due to pre-harvest sprouting will be as high as 60-70%. High yielding varieties developed/identified in recent years, despite their high yield potential, could not increase/stabilize the yields of this crop due to lack of resistance to pre-harvest sprouting. Therefore, an attempt was essentially made to develop tolerant varieties to pre-harvest sprouting in the current investigation. Methods: The F2 (Healthy and well dried) seeds derived from the crosses DGGV-2 ´ Pant Moong-1 were irradiated with 60 kR gamma rays for the creation of desirable variability. The gamma rays irradiated seeds were sown in during kharif-2017 along with their respective checks to grow the F2M1 generation. Further advanced to F2M2. The individual plants were critically observed at maturity for morphological traits viz., small pod beak length and angle, thick pod wall and hard seededness that determine the tolerance to PHS. The mutant lines were compared with the parental lines viz., shattering tolerant variety Pant Moong-1 as well as susceptible variety DGGV2. The putative mutants selected and tagged in F2M2 and the seeds were harvested separately and forwarded to develop the F2M3 mutant population (1000 plants) in summer-2018. The seeds from F2M3 generation were harvested on individual plant basis and were sown. 806 progenies were sown in augmented design along with the checks in each block during kharif 2019. Thus from the population of 24812 such derived plants, genotypes with small pod beak and angle, thick pod wall, hard seededness and higher epicuticular wax and lignin content were isolated in F2M3 and F2M4. Further a total of 49 advanced breeding lines along with a known shattering susceptible check were studied for the morphometric and biochemical parameters governing the pre harvest sprouting. Result: Lower PHS was recorded in DGGV-79 (0.02%), DGGV-125 (0.02%) and DGGV 195 (0.91%). Higher phenol content was recorded in DGGV-125 (9.43 mg GA eq /g) and DGGV-79 (9.37 mg GA eq /g). Higher lignin content was recorded in DGGV-125 (6.42 mg/g) and DGGV-79 (6.10 mg GA eq /g). Further correlation analysis revealed that negative correlation of PHS was observed for epicuticular wax (r= -0.983), phenol (r= -0.892), lignin content (r= -0.981) and hard seed percentage (r= -0.942). Significant negative correlation was observed between PHS and pod wall thickness (r= -0.570). Pod beak length recorded highly significant positive correlation (r= 0.911) to PHS. Genotypes with inherent tolerance to seed shattering hold a promise to minimize yield losses due to viviparous germination.

Exploring the impact of soil water variability and varietal diversity on alfalfa yield, nutritional quality, and farm profitability

AbstractBackgroundDespite high nutritional and economic value, alfalfa yield has not been improved in the United States. Soil moisture critically influences alfalfa's yield and quality, affecting its physiological processes, nutrient uptake, and stand growth. Additionally, the maturity stage at harvest can significantly impact both hay yield and quality. Thus, this study aimed to assess the effect of different soil moisture levels and harvesting times on forage yield, nutritive value, and the overall profitability of commercially cultivated alfalfa.MethodsTwo conventional and three lower‐lignin alfalfa varieties were planted in a randomized complete block with split plot design under drought, rainfed, and irrigation conditions in 2020 in Manhattan, Kansas, USA. The dry matter yield (DMY) and forage nutritive value were evaluated at late bud, early flowering, and 7 days after early flowering stages, respectively.ResultsDMY varied with production year, soil water availability, and growth stages, with drought conditions causing a decline in DMY of 5% to 38% in the second production year. Water conditions and maturity stages influenced crude protein (CP) and in vitro dry matter digestibility (IVDMD). Higher soil moisture and advancing maturity stages negatively impacted CP, IVDMD, and relative forage quality. The study revealed net profit margins of 62%, 64%, and 52% for drought‐prone, rainfed, and irrigated production, respectively.ConclusionsHarvest timing and irrigation practices were found to have substantial implications for forage yield and nutritive value of alfalfa. The yield‐quality trade‐off differed under drought and irrigation, with early harvesting leading to lower yields but higher protein content and digestibility. The study findings provide potential guidance for improving alfalfa hay yield, quality, and profitability.

Influence of Planting Dates and Biohealth on Growth and Yield of Physalis peruviana L. Plant

An experiment was conducted to evaluate effect of planting dates and Biohealth on growth and yield of (Physalis Peruviana L.) plant at field of Directorate of Agriculture Research Center in Erbil, Kurdistan Region – Iraq. The experiment was laid out in Factorial Randomized Complete Block Design replicated three with nine treatments, and the experiment included three different Planting dates (2nd February, 17th February and 4th March) and Biohealth doses (0, 8, 16 g/1). The results of the experiment demonstrated that the first date of Planting (2nd February) produced early flowering and the greatest branch number. The maximum plant height and stem diameter were found from 4th March Planting. Moreover, the earliest flowering was recorded from the plant treated with 8 g/L Biohealth and control plant. The greatest numbers of branches and stem diameter were gained from the plant treated with Biohealth 8 g/l. The highest value of plant height was measured in the treatment (control plants + 4th March Planting), while the treatment of (Biohealth 8 g/l + 2nd February) was indicated the greatest number of branches. The shortest flowering period was recorded in the combination of (2nd February without Biohealth) and (2nd February with Biohealth 8 g/L). The best result of total Carotenoid in Physalis peruviana L fruits were gained from the first date (17th February) and third date (4th March) of Planting, while Biohealth 16 g/1 provided the best result of the total carotenoid. The best level of total carotenoid was investigated from the treatment (2nd February + Biohealth 16 g/l).

Evaluation of plant characteristics of early harvesting hybrid chili lines

Chili pepper is a popular horticultural commodity grown across the tropics, including Indonesia. The availability of chili varieties, particularly hybrids, may extend options for growers as well as consumers, depending on their personal preferences and needs. In 2022, research was conducted in the Lembang highlands agroecosystem, West Java, Indonesia, with the aim to evaluate plant characteristics including plant morphology and production of F1 chili lines. Five genotypes were employed in a complete randomized block design with four replications, including two F1 lines (1 x 5 and 5 x3) and three commercial F1 hybrid varieties (Carla Agrihorti, Hot Beauty, and Inata Agrihorti). The 1 x 5 line had a short plant posture, characterized by the short stem length, internodes, and plant height. This line also had the earliest flowering (44.25 dap) as well as harvesting (96 dap). This 1 x 5 line‘s advantage was complimented by a high yield of 16.7 tons Ha-1. The F1 1 x 5 line is expected to be efficient in the use of water, fertilizer, and pesticides due to its short plants and early harvest but high yield, allowing it to contribute to sustainable agriculture and have a beneficial impact on the environment.

Chlorophyll Fluorescence Parameter as a Tool in Selecting Heat-tolerant Summer-flowering Chrysanthemum (Dendranthema ×grandiflorum)

Chrysanthemum ‘Bai Tian Xing’, ‘Huang Ching Chin’, ‘Pink Pearl’, and ‘NCHU-001’ plants were preheated at 35 °C for 24 hours to induce heat tolerance. The recently fully expanded leaves were detached, kept in a moist Ziploc bag, and then subjected to 35, 40, 45, 47.5, 50, 52.5, 55, 60, or 65 °C for 20 minutes. After dark-acclimatized at room temperature for 30 minutes, leaves were measured for Fv/Fm value with a chlorophyll fluorescence parameter. Results showed that ‘Bai Tian Xing’ had the highest critical (Tcrit) and midpoint temperature (Tmid). Mean Tcrit and Tmid were shown to be 47 and 50 °C, respectively, and Tmid gave greater distinguishment of Fv/Fm value among cultivars. Plants of four cultivars were acclimatized at 15 to 40 °C for 3 days and 35 °C being the most effective temperature to induce a heat-tolerant response in chrysanthemum. Required inducing time to reach a stable leaf Fv/Fm value ranged from 4.6 to 11.1 hours among cultivars. All cultivars had similar required time to reach visible bud between summer and autumn crops (except NCHU-001), but all had delayed flowering in the summer crop. There is a negative linear relationship between flowering heat delay and leaf Fv/Fm value (R2 = 0.93). Progenies from reciprocal crossing of ‘Bai Tian Xing’ × ‘NCHU-001’ and ‘Huang Ching Chin’ × ‘Pink Pearl’ were also subjected to treatments for Fv/Fm measurements and observed for time to flowering in the summer crop. All combinations showed negative linear relationship between time to flowering and leaf Fv/Fm value (R2 = 0.70–0.87). Two plants, 109-W001Y and 109-W003Pi, showed early flowering habit and good flower performance under heat conditions were selected. All four cultivars and the two selected lines were measured for photosynthetic parameters under day/night temperatures of 35/30 or 25/20 °C in growth chambers. All cultivars and lines showed decreased net photosynthetic rate and dark respiration rate under 35/30 °C when compared with 25/20 °C. Relatively higher net photosynthetic rate and lower dark respiration rate in ‘Bai Tian Xing’, ‘109-W001Y’, and ‘109-W003Pi’ under 35/30 °C, when compared with the other three cultivars, might have contributed to better flowering performance in the summer.

Can agronomic options alleviate the risk of compound drought-heat events during the wheat flowering period in southeastern Australia?

The impacts of compound drought-heat (DH) events on crops are more devastating than a single extreme event of drought or heat. Previous studies mainly assessed the change of individual extreme climate events. However, studies quantifying the characteristics of DH events during crop growth periods are still lacking. To the best of our knowledge, there is no study that has quantified the potential of adjusting sowing time and changing cultivars to reduce the risk of DH events for wheat in Australia. We aimed to (1) develop a combined index to capture the DH events occurring during the wheat flowering period at six study sites in southeastern Australia’s wheat belt; (2) quantify the changes in the frequency (DHF), duration (DHD), and intensity (DHI) of DH events under future climate; and (3) identify feasible agronomic options to reduce the risk of DH events. We used the APSIM model driven by climate projections from 27 GCMs for the period of 1981–2100 to simulate the wheat flowering time and daily plant available water (PAW) at 0–100 cm soil layer. The wheat sensitive period (WSP) was defined as the period from 2 weeks before flowering to 2 weeks after flowering time. A DH event occurs when the daily maximum temperature is higher than 28 ℃ and daily PAW is less than 40% of plant available water capacity for three consecutive days or more. Then, we assessed the DHF, DHD, and DHI under projected climate change. Finally, we investigated the potential of changing sowing time and cultivars to alleviate DHF, DHD, and DHI under different climate scenarios. According to the average values across six sites, the DHF, DHD, and DHI during the WSP increased by 15%, 12%, and 0.9% in 2040 s, and 49%, 44%, and 5% in 2080 s, respectively, compared to 2000 s. Such increases in DH events were mainly due to enhanced heat events. Early sowing and planting better-performing wheat cultivars with early flowering had great potential to lower the risk of future DH events. They could reduce the DHF, DHD, and DHI by 15%− 100%, 18%− 100%, and 16%− 100%, respectively, compared to without adaptation options. However, the strategy may introduce an increased frost risk across six sites, especially in regions with climates that are less dry and hot, such as Mudgee and Wagga Wagga. We expect our modelling work can provide useful information for developing effective agronomic management practices to help Australian wheat growers better prepare for DH events under climate change. The newly proposed DH framework can be applied to other dryland wheat growing regions globally.

Effect of chemical thinning on the fruit parameters of ‘Majhoul’ date palm during fruit development

The aim of this work was to study the effect of NAA (Naphthalene acetic acid) on the chemical thinning of ‘Majhoul’ date palm in order to use this operation as an alternative to manual thinning, which is a costly operation carried out by the farmers. Experiments were carried out on an adult plantation of ‘Majhoul’ cv in Tafilalet area. Thinning treatments used were T0 (control treated with water), T1 (application of 150 and 300 ppm NAA 30 and 60 days after pollination), T2 (application of 250 and 500 ppm NAA 30 and 60 days after pollination) and T3 (manual thinning performed by the farmer). These treatments were used on three flowering phases of this variety. Obtained results showed that for the early flowering phase, T2 NAA treatment increased fruit drop for 77% compared to the control. Thinning treatments T1, T2 and T3 yielded fruit with larger size (fruit mass of 17.26, 18.51 and 20.88 g respectively) than that of the control (13.67 g). The late flowering phase also gave fruit with larger size (fruit mass of 18.73 g and fruit length of 4.44 cm) than that of the other flowering phases (fruit mass of 17 g and fruit length of 4.34 cm for the other flowering phases).

Unisexual flowers as a resolution to intralocus sexual conflict in hermaphrodites.

In dioecious populations, males and females may evolve different trait values to increase fitness through their respective sexual functions. Because hermaphrodites express both sexual functions, resolving sexual conflict is potentially more difficult for them. Here, we show that hermaphrodite plants can partially resolve sexual conflict by expressing different trait values in different male and female modules (e.g. different flowers, inflorescences, branches etc.). We analysed the flowering phenology, sex allocation and selection gradients on floral traits of flowers of the andromonoecious plant Pulsatilla alpina, which produces both bisexual and male flowers. Our results indicate that strong protogyny prevents early bisexual flowers from profiting from high siring opportunities early in the reproductive season at a time when male flowers could achieve high siring success. The production of unisexual male flowers thus resolves this sexual conflict because it allows the flowers to express their male function without waiting until after the female function has been performed. Our study illustrates the resolution of sexual conflict arising from phenological constraints via modular divergence in sex allocation. We discuss the extent to which modular variation in sex allocation in the context of other sexual systems may be similarly explained.

ZmELF6-ZmPRR37 module regulates maize flowering and salt response.

The control of flowering time in maize is crucial for reproductive success and yield, and it can be influenced by environmental stresses. Using the approaches of Ac/Ds transposon and transposable element amplicon sequencing techniques, we identified a Ds insertion mutant in the ZmPRR37 gene. The Ds insertion showed a significant correlation with days to anthesis. Further research indicated that ZmPRR37-CR knockout mutants exhibited early flowering, whereas ZmPRR37-overexpression lines displayed delayed flowering compared to WT under long-day (LD) conditions. We demonstrated that ZmPRR37 repressed the expression of ZmNF-YC2 and ZmNF-YA3 to delay flowering. Association analysis revealed a significant correlation between flowering time and a SNP2071-C/T located upstream of ZmPRR37. The SNP2071-C/T impacted the binding capacity of ZmELF6 to the promoter of ZmPRR37. ZmELF6 also acted as a flowering suppressor in maize under LD conditions. Notably, our study unveiled that ZmPRR37 can enhance salt stress tolerance in maize by directly regulating the expression of ABA-responsive gene ZmDhn1. ZmDhn1 negatively regulated maize salt stress resistance. In summary, our findings proposed a novel pathway for regulating photoperiodic flowering and responding to salt stress based on ZmPRR37 in maize, providing novel insights into the integration of abiotic stress signals into floral pathways.

Does the Distance from the Formal Path Affect the Richness, Abundance and Diversity of Geophytes in Urban Forests and Parks?

Geophytes are a characteristic element of deciduous forests in the temperate zone, as well as a common component of urban green spaces due to their early flowering and high decorative value. Nevertheless, in urban areas, geophytes are constantly threatened by recreational activities, especially in parks where intensive trampling occurs. In this study, we tested the effect of the distance from formal paths on the species richness, abundance and diversity of geophytes in relation to habitat conditions in urban forests and parks. We established a total of 400 plots (1 m × 1 m) located close (CL) to and further (FU) from paths in 10 forests and 10 parks in Kraków, southern Poland, in spring 2022. We recorded 23 species from nine groups of geophytes forming different underground storage organs, i.e., bulbs (B), hypocotyl bulbs (HB), rhizomes (RH), runners (RU), runners and rhizomes (RU-RH), runner-like rhizomes (RL-RH), runners and runners with tuberous tip (RU-TU), runners and shoot tubers (RU-ST) and root tubers (RT). The differences in the number, share and cover-abundance of geophytes between the CL and FU plots were statistically insignificant. In contrast, the total number, share and cover-abundance of geophytes were significantly higher in forests than in parks. Additionally, the share and cover-abundance of RH and RT were significantly higher in forests than in parks. Moreover, in CL plots in forests and parks, the cover-abundance of RH and RT were negatively correlated with soil compaction. Urban forests provide a high abundance of RH, RU-RH and RT, while parks support a high abundance of BU. To protect forest geophytes in urban forests and parks, it is recommended to limit trampling and soil eutrophication, as well as reduce the increase in soil pH along paths.

Indicators of efficiency in operational crosses of Eucalyptus dunnii and hybrids in Montes del Plata: Current progress and challenges

One of the main goals of a tree breeding program is to increase forest productivity, adaptation and profitability of forest plantations. Eucalyptus dunnii is a main species used for pulp production in Uruguay. Montes del Plata (MdP) is one of the largest forest companies in Uruguay and has been focused on the development, testing and deployment of E. dunnii clones to establish commercial plantations in Uruguay. This poster refers to the generation of control-pollinated families, as the starting point of MdP clonal strategy. Control pollination (CP) is a tool in genetic breeding programs that enables to recombine selected genotypes with desired traits to maximize gain in the medium to long term. The selection trait for pulpwood objective is tons of cellulose per tree (ADt); consequently, growth, frost tolerance, health, and wood properties are relevant for parent selection. Ongoing work shows a fruitfully performance of E. dunnii. In the south-east region of Uruguay the species have one flowering period per year, with an average flowering time occurring between the last fortnight of February and the first half of May. Developed protocols for pollen harvesting and methods for crossing are used. The survival of pollinated flowers resulting in fruits has shown to vary with parental species. Average survival rates are 20 to 35%. The main loss of crop happens during the first 4 months after pollinating, weighting —in average— a loss of 40% of the pollinated flowers. The species fruit crop occurs one year after CP. The number of seed per fruit varies with the parental species. E. dunnii × E. dunnii crosses yield in average 6.4 seeds per fruit. However, we have seen a reduction in seeds per fruit in hybrid crosses, where E. dunnii is pollinated with another species, mostly E. globulus, E. grandis and E. dorrigoensis. Seed crops are sawn in the nursery and start an individual clonal selection based on rooting protocols. Clones that fulfill the rooting constraints go to field trials. This is presented in another poster proposal. Main challenges for the future are to maintain a wide genetic diversity in the breeding population, early flowering, and continuous improvement on CP techniques.