Flower Abortion Research Articles

Molecular cloning and characterization of heat-responsive LcOPR1, a gene encoding oxophytodienoic acid reductase in lentil.

Improving crop plants using biotechnological implications is a promising and modern approach compared to traditional methods. High-temperature exposure to the reproductive stage induces flower abortion and declines grain filling performance, leading to smaller grain production and low yield in lentil and other legumes. Thus, cloning effective candidate genes and their implication in temperature stress tolerance in lentil (Lens culinaris Medik.) using biotechnological tools is highly demandable. The 12-oxophytodienoic acid reductases (OPRs) are flavin mononucleotide-dependent oxidoreductases with vital roles in plants. They are members of the old yellow enzyme (OYE) family. These enzymes are involved in the octadecanoid pathway, which contributes to jasmonic acid biosynthesis and is essential in plant stress responses. Lentil is one of the vital legume crops affected by the temperature fluctuations caused by global warming. Therefore, in this study, the LcOPR1 gene was successfully cloned and isolated from lentils using RT-PCR to evaluate its functional responses in lentil under heat stress. The bioinformatics analysis revealed that the full-length cDNA of LcOPR1 was 1303 bp, containing an 1134 bp open reading frames (ORFs), encoding 377 amino acids with a predicted molecular weight of 41.63 and a theoretical isoelectric point of 5.61. Bioinformatics analyses revealed that the deduced LcOPR1 possesses considerable homology with other plant 12-oxophytodienoic acid reductases (OPRs). Phylogenetic tree analysis showed that LcOPR1 has an evolutionary relationship with other OPRs in different plant species of subgroup I, containing enzymes that are not required for jasmonic acid biosynthesis. The expression analysis of LcOPR1 indicated that this gene is upregulated in response to the heat-stress condition and during recovery in lentil. This study finding might be helpful to plant breeders and biotechnologists in LcOPR1 engineering and/or plant breeding programs in revealing the biological functions of LcOPR1 in lentils and the possibility of enhancing heat stress tolerance by overexpressing LcOPR1 in lentil and other legume plants under high temperature.

Does the soil microbial community facilitate Mimosa pudica's biological performance under abiotic stress? Growth, tolerance mechanisms, and seismonastic behaviour

Climate change effects such as soil salinisation or drought dramatically affect native and potentially invasive plant species. Mimosa pudica, originally native to South America but spread to Africa and Asia, exhibits great adaptability to disturbed environments in tropical and subtropical areas. It has become a model organism for studying thigmomorphogenetic behaviour due to its ability to display fast responses to mechanical stimuli. We investigated the effects of salt and water stresses on M. pudica in interaction with a Mediterranean coastal dune microbial community by growing plants on soils collected from dunes near Valencia, Spain. Plant biomass, potential mechanisms of stress tolerance, seismonastic response, and phenology were assessed. Abiotic stress, particularly salt stress, adversely affects plant performance and seismonasty. Mimosa pudica, however, displayed the blockage of Na+ transport at the root level as a primary defence mechanism against salinity. When exposed to natural soils, plants produced more leaves and flowers, with lower flower abortion rates than plants in a sterile substrate, and the stimulated plants displayed faster responses across time before reaching a plateau, while the recovery increased with time. Our results highlight the need for integrative and multidisciplinary approaches to understand plant-abiotic stress-microorganisms interactions. In M. pudica, soil microorganisms had weak or no effects on biomass or biochemical stress markers; however, their presence strongly improved reproductive traits and seismonasty, thus facilitating potential plant establishment in a new environment.

Impact of Soil Moisture Depletion on Various Yield Components and Water Usage to Trigger Pods in Chickpea (Cicer arietinum L.) Desi Genotypes

ABSTRACTChickpeas are well adapted to rainfed conditions, but a lack of moisture during the reproductive phase can result in lower pod setting and ultimately reduced grain yield. The exact reasons for this reduction are not fully understood, partly because of the lack of information on soil moisture content (SMC) and water use during podding. This study aimed to address this knowledge gap by quantifying the impact of gradual drought on various yield components of desi‐type genotypes using the fraction of transpirable soil water (FTSW) method. Two water treatments were applied at the start of anthesis: well‐watered (WW) and drought‐stressed (DS). The WW was maintained at 24% SMC, whereas the DS was dried to 3% SMC. The results showed that DS caused early podding (3.3 days less), with reductions in plant height (11.4 cm), leaf area (1249.5 cm2), flowers (18.6), pods (27.4), seeds (37.0), grain yield (0.2 g), aboveground dry biomass (11.4 g) and harvest index (0.2 g), while increasing flower abortion (14.6) and seed biomass (1.5 g). However, diverse genotypic responses were observed to treatments, as well as water usage, FTSW and SMC that triggered pods which ranged from 1.12 to 1.89 L, 0.05 to 0.43 and 4.0% to 12.2%, respectively. A positive association between days taken and the amount of water used to terminate pods indicated that quicker‐triggering genotypes, such as Rupali and Genesis 836, consumed less water to develop pods than Flipper, ICCV_06109 and PBA Slasher did. Conversely, the negative association between the amount of water used and the number of pods triggered, seeds and grain yield explained the superior performance of Rupali and Genesis 836. These genotypes extracted less water (FTSW = 0.36 and 0.43; SMC = 10.3% and 12.2%, respectively) to develop pods and maintained favourable photosynthesis at lower transpiration rates for longer periods, allowing them to use residual moisture more efficiently. Our research offers crucial insights that can be beneficial to breeders and physiologists, paving the way for future studies aimed at developing drought‐tolerant genotypes.

Aphelenchoides besseyi Parasitizing Tobacco Cultivars in Brazil.

Foliar nematodes (Aphelenchoides spp.) are known to be parasites of tobacco in restricted areas, but symptoms caused by A. besseyi in tobacco are not well characterized, despite the great importance of this nematode worldwide. This study aimed to evaluate the host reaction of four Nicotiana tabacum cultivars (Comum, Xanthi, Samsun, and TNN) and N. benthamiana cultivar Comum to A. besseyi and to characterize the symptoms and the parasitism of this nematode. Two experiments were conducted under greenhouse conditions with controlled humidity and temperature, in which the plants were inoculated with 600 A. besseyi. At 30 days after inoculation (DAI), nematodes present in the soil, roots, and shoot parts were extracted, and roots and shoot tissues were stained with acid fuchsin. A high number of A. besseyi was obtained per gram of shoot tissues (125 to 2,169 nematodes), and severe symptoms were observed in leaves and inflorescences of all cultivars. The symptoms included foliar distortion and deformation, necrotic spots delimited by the veins, flower abortion, and poor development of plants. In addition, A. besseyi was observed to penetrate tobacco roots at 30 DAI, and nematodes were also observed in the foliar mesophyll, inflorescences, and stems, a parasitism that has not been previously reported in tobacco plants. The disease caused by A. besseyi in tobacco could be a concern for growers in southern and northeastern Brazil because this nematode can cause severe damage to the marketable leaves of tobacco, reducing its commercial value.

Colletotrichum species associated with atemoya anthracnose in northeast Brazil

Anthracnose, caused by Colletotrichum spp., is an important disease of atemoya that can infect and cause damage to different plant organs. The symptoms include foliar anthracnose, flower abortion, branch tip bleaching, and necrotic lesions on fruits. Knowing the etiology of this disease is essential for properly developing management strategies. Therefore, this study aimed to identify Colletotrichum species associated with atemoya in the Northeast region of Brazil, based on multi-locus phylogeny and morphological analyses, to better understand the etiology of anthracnose in this plant species. The Colletotrichum isolates were obtained from symptomatic leaves and branches of atemoya collected in commercial fields in Vitória da Conquista (Bahia), Palmeira dos Índios and Rio Largo (Alagoas), located in northeast Brazil. The initial analysis of the partial sequences of the GAPDH gene was performed with nineteen Colletotrichum isolates obtained from leaves and branches of atemoya trees with typical anthracnose symptoms. Seventeen isolates were grouped in the gloeosporioides complex and two in the boninense complex. Therefore, eleven isolates were submitted to concatenated phylogenetic analyses with the genes GAPDH, TUB2, and ITS region of the rDNA to confirm the identity of the isolates at the species level. The species C. theobromicola, C. siamense, C. fructicola and C. karstii were identified and are associated with atemoya anthracnose in the Northeast region of Brazil.

Assessment of farmers’ knowledge on the foliar fertilizer use for improved cashew (Anacardium occidentale L) productivity in south-eastern Tanzania

Purposethe study aim was to evaluate the farmers' knowledge on fertilizer use in cashew by assessing their awareness on the fertilizers, extent of use, obtained benefits from use in cashew, limiting factors of use, availability and changes after use. Cashew (Anacardium occidentale L) is a recent topmost strategic crop in Tanzania. Through cashew, earnings of > $585 million were reached in 2017/18 season. Chlorosis, flower abortion and dropping of immature nuts hinder cashew production referring the decrease from 3200,000 Metric Tons (MT) in 2017/18 to less than 200,000 MT in 2021/2022. Farmers’ knowledge on fertilizer use in cashew is not precisely known. Methodsthrough cross-section design using questionnaires, purposive sampling of respondents was done. Four villages each from three agro-ecologies i. e, Makonde Plateau (MP), Tunduru Dissected Plains (TDP), and Masasi-Nachingwea Plains (MNP) were selected in South-eastern, Tanzania. About 480 households were interviewed. Resultsabout 75% of respondents were aware of foliage fertilizers while 45.4% agreed on their suitability for cashew. About 44.7%, 27.9%, and 27.4% of respondents use foliar fertilizers in TDP, MP, and MNP, respectively. Some respondents (3.7%) apply 1 L of foliage fertilizers per round acre−1 and 5.1% apply for 1–3 rounds, and some few (1%) apply up to 10 rounds season−1. Cashew farming experience and credit access negatively influenced foliar fertilizer uses; hence foliar fertilizer prices linearly reduced the extent of use. Conclusionlimited knowledge among the farmers on fertilizer use in cashew was a challenge. Therefore, farmers' training and detailed fertilizer use research are recommended.

An NnSnRK1-centered regulatory network of shade-induced early termination of flowering in lotus

The flowering process of lotus is highly sensitive to environmental conditions such as canopy shade and cloudy days, which often lead to abortion of the flower buds. However, the underlying mechanisms remain largely unknown. Based on transcriptome analysis and genetics screens, we found that silencing of SNF1-related protein kinase 1 (NnSnRK1) gene in lotus could promote flowering and reduce flower bud abortion under carbon starvation induced by 70% shade. Transcriptome analysis of NnSnRK1-overexpressed or -silenced lotus revealed that DEGs were mainly associated with ROS homeostasis, cell enlargement, and autophagy processes. Excessive autophagy levels and cell death were detected in the aborting flower buds. We further used NnSnRK1 as the bait to screen the yeast two-hybrid library constructed with RNA isolated from mixed lotus flower buds, and identified 14 putative interacting proteins of NnSnRK1. Two novel negative regulators of NnSnRK1, mediator of ABA regulated dormancy1 (NnMARD1) and 4-coumarate-CoA ligase-like 5 (Nn4CLL5), were identified. Overexpression of NnMARD1 and Nn4CLL5 could promote flowering of lotus under 70% shade, while silencing of them further inhibited flowering. Our results revealed a NnSnRK1-centring regulatory network that produced aborted flower buds during carbon starvation, which could improve reproductive success, and act like an energy-efficient measure of plants.

Pollen Viability, and the Photosynthetic and Enzymatic Responses of Cowpea (Vigna unguiculata (L.) Walp., Fabaceae) in the Face of Rising Air Temperature: A Problem for Food Safety

Rising temperature affects agricultural production, causing food insecurity. Thus, the objective of this study was to evaluate how increased temperature influences pollen viability, photosynthetic and enzymatic responses, and their consequences on the final yield of cowpea cultivars. The cultivars BRS Acauã, BRS Guariba, BRS Gurguéia, and BRS Pajeú were used, kept in growth chambers under two temperature regimes: 24.8–30.8–37.8 °C and 20–26–33 °C. The cultivars BRS Acauã, BRS Guariba, and BRS Pajeú showed prolonged flowering and greater flower abortion, at 23.58%, 34.71%, and 25.55%, respectively, under an increase of 4.8 °C in temperature. This increase also reduced the viability of BRS Acauã and BRS Pajeú pollen by 34 and 7%, respectively. Heating increased stomatal opening and transpiration but reduced chlorophyll content. The enzymatic response varied according to cultivars and temperature. Changes in photosynthetic and enzymatic activities contribute to reducing pollen viability and productivity. BRS Acauã was the most affected, with an 82% reduction in the number of seeds and a 70% reduction in production. BRS Gurguéia maintained its production, even with an increase of 4.8 °C, and can be selected as a cultivar with the potential to tolerate high temperatures as it maintained pollen viability, with less flower abortion, with the synchrony of physiological and biochemical responses and, consequently, greater production.

Far-red light-enhanced apical dominance stimulates flower and fruit abortion in sweet pepper.

Far-red radiation affects many plant processes, including reproductive organ abortion. Our research aimed to determine the role of apical dominance in far-red light-induced flower and fruit abortion in sweet pepper (Capsicum annuum L.). We conducted several climate room experiments where plants were grown under white- or red-rich LED light, with or without additional far-red light. Additional far-red light enhanced apical dominance: it increased auxin levels in the apices of dominant shoots, and caused a greater difference in internode length and apical auxin levels between dominant and subordinate shoots. Additional far-red light stimulated fruit abortion in intact plants but not in decapitated plants, suggesting a crucial role of shoot apices in this effect. However, reducing basipetal auxin transport in the stems with N-1-naphthylphthalamic acid did not influence far-red light-stimulated fruit abortion, although auxin levels in the stem were largely reduced. Applying the synthetic auxin 1-naphthaleneacetic acid on decapitated apices did not influence fruit abortion. However, applying the auxin biosynthesis inhibitor yucasin to shoot apices reduced fruit abortion regardless of the light conditions, accompanied by slight shoot growth retardation. These findings suggest that the basipetal auxin stream does not mediate far-red light-stimulated fruit abortion. Far-red light-stimulated fruit abortion was associated with reduced sucrose accumulation and lower invertase activities in flowers. We suggest that under additional far-red light conditions, increased auxin levels in shoot apices promote fruit abortion probably through enhanced competition for assimilates between apices and flowers, which limits assimilate import into flowers.

Seasonal Analysis of Yield and Loss Factors in Bt Soybean Crops in North Brazil

Tropical crops face significant challenges from abiotic and biotic stressors, resulting in substantial losses. This study aimed to assess the yield and losses in Bt soybean crops in Tocantins state, northern Brazil, during the 2017/2018 and 2018/2019 growing seasons. We monitored and estimated yield losses and their contributing factors in commercial fields, spanning dry and rainy seasons, from planting to harvest. Our findings revealed that crop yields remained consistent between the dry season (4349.85 kg/ha) and the rainy season (4206.51 kg/ha). Similarly, the overall yield loss showed no significant variation between seasons, with values of 902.86 kg/ha (dry) and 1007.92 kg/ha (rainy). Nevertheless, the factors contributing to these losses exhibited season-dependent variations. We observed higher plant mortality rates during the dry season, whereas insects (particularly stink bugs) and fungi were the primary contributors to grain yield losses during the rainy season. Conversely, losses due to flower abortion and pod malformation remained relatively consistent between the two seasons. Our study underscores the increase in soybean yield in one of Brazil’s agricultural frontiers. While overall yield and losses remained stable between dry and rainy seasons, the distinct seasonal patterns influencing yield losses call for nuanced and season-specific strategies in sustainable crop management.

Dynamic plant spacing in tomato results in high yields while mitigating the reduction in fruit quality associated with high planting densities.

High planting densities achieve high light interception and harvestable yield per area but at the expense of product quality. This study aimed to maintain high light interception without negative impacts on fruit quality. Dwarf tomato was grown at four densities in a climate-controlled room-at two constant densities (high and low) and two dynamic spacing treatments (maintaining 90% and 75% ground coverage by decreasing planting density in 3-4 steps)-resulting in ~100, 19, 54, and 41 plants/m2 averaged over 100 days of cultivation, respectively. Constant high density resulted in the highest light use efficiency (LUE; 7.7 g fruit fresh weight per mol photons incident on the canopy) and the highest harvestable fruit yield (11.1 kg/m2) but the lowest fruit size and quality. Constant low density resulted in the lowest LUE and yield (2.3 g/mol and 3.2 kg/m2, respectively), but higher fruit size and quality than high density. Compared to low density, maintaining 90% ground coverage increased yield (9.1 kg/m2) and LUE (6.4 g/mol). Maintaining 75% ground coverage resulted in a 7.2 kg/m2 yield and 5.1 g/mol LUE. Both dynamic spacing treatments attained the same or slightly reduced fruit quality compared to low density. Total plant weight per m2 increased with planting density and saturated at a constant high density. Assimilate shortage at the plant level and flower abortion lowered harvestable fruit yield per plant, sweetness, and acidity under constant high density. Harvestable fruit yield per plant was the highest under dynamic spacing and low density. Under constant high density, morphological responses to lower light availability per plant-i.e., higher specific leaf area, internode elongation, and increased slenderness-coincided with the improved whole-plant LUE (g plant dry weight per mol photons). We conclude that a constant high planting density results in the highest harvestable fruit yield per area, but with reduced fruit quality. Dynamic spacing during cultivation produces the same fruit quality as constant low density, but with more than double the harvestable yield per area.

Influence of sowing season on some quality indices for soybean

Soybean quality indices, like yield, can be influenced by factors such as climatic conditions, applied technology or biological material. Soybean is a short-day species with moderate temperature requirements, especially during flowering, a critical period for achieving yield and crop quality, air temperature in the range of 17-18°C is considered the biological minimum, while the range of 22-25°C is considered optimal. High temperatures during the flowering period can cause significant yield losses through flower abortion especially when correlated with insufficient humidity. This paper presents summary data obtained in soybean cultivation under the conditions of the Transylvanian Plateau at Agricultural Research and Development Turda on the influence of sowing time on some quality indices. The experiment was realized using the block method in subdivided plots with 3 factors AxBxC on a type soil chernozem, characteristic of the Transylvanian Plateau with chemical description, the soil has a neutral to low alkaline pH, neutral to high humus content, well supplied in nitrogen and potassium, medium supplied in phosphorus. During three experimental years 2021 - 2023 climatic conditions and sowing times influenced differently the protein and fat content of 5 soybean varieties. The results obtained were statistically processed by the analysis of variance method and determination of the least significant difference - LSD - (5%, 1% and 0.1%).

Effect of aminoethoxyvinylglycine addition on the floral bud opening of Ranunculus asiaticus L cultivars

Objective: To evaluate the effect of aminoethoxyvinylglycine (AVG) additions on several growth variables of R. asiaticus in a greenhouse under a typically dry environment of the Mexicali valley.
 Design/methodology/approach: The variables determined were, bud opening rate, flower diameter, height of stem and bud growing rate and completely randomized block experimental design under a 2 by 4 factorial arrangement and three replicates was used for setting up the treatments with rates AVG of 0,100,150 and 200ppm over La Belle Deep Rose (DER) and La Belle Dark Orange (DAR) R. asiaticus cultivars.
 Results: The optimal dose of AVG for reducing flower bud diameter on both cultivars were those of 200 and 100 ppm respectively. Also, AVG addition had a significant effect in reducing stem height and growing rate for both cultivars.
 Limitations on study/implications: The use of AVG has shown good results as inhibitor of ethylene synthesis and extension of shelf life in carnations, snap dragons (Antirrhinum), ripening of fruits, and to reduce abortion of female flowers in certain species of walnuts, so, based on the above and considering the lack of information regarding the use of AVG inhibitor in the opening of Persian Buttercup flower buds was used AVG in R. asiaticus.
 Findings/conclusions: AVG addition on plants of R. asiaticus had a significant effect reducing growth, both in diameter and height in the La Belle Deep Rose (DER) and La Belle Dark Orange (DAR) varieties

Exploring the Role of Calcium in the Physiology of Tulipa: A Comparative Study across Different Cultivars

Cut tulip flower production, typically cultivated using hydroponic systems, often faces the challenge of stem toppling due to calcium (Ca) deficiency in the nutrient solution. Growers generally grow various tulip cultivars to meet market demands. In hydroponic production, plants require precise nutrient concentrations to promote growth and development, as the food reserves in the mother bulb are insufficient and vary depending on the plant cultivar. This study aimed to assess the impact of different tulip cultivars and Ca deficiency on tulip growth, flowering, and physiological changes. Two cultivars of tulip, namely, ‘Strong Gold’ and ‘Orange Juice’, were subjected to three distinct nutrient solution treatments, namely (1) deionized water (DI) only (without any plant nutrition added), (2) complete solution (Hoagland’s complete nutrient solution), and (3) Ca deficiency solution. The results indicate that the ‘Orange Juice’ tulip was particularly susceptible to Ca deficiency, exhibiting stem toppling and flower abortion similar to those grown in DI. Ca deficiency led to a reduction in root length and leaf area but did not affect the plant height. Additionally, it had a negative impact on bulb qualities, resulting in a decreased bulb fresh weight and bulb circumference in both tulip cultivars. Furthermore, Ca deficiency and DI reduced the photosynthetic rates, and Ca deficiency increased the transpiration rate in the tulip. The leaf concentrations of nitrogen (N), phosphorus (P), and Ca were decreased under Ca deficiency and DI, while magnesium (Mg) levels increased under Ca deficiency treatment compared to the complete nutrient solution treatment.

NnSnRK1-NnATG1-mediated autophagic cell death governs flower bud abortion in shaded lotus.

Many plants can terminate their flowering process in response to unfavourable environments, but the mechanisms underlying this response are poorly understood. In this study, we observed that the lotus flower buds were susceptible to abortion under shaded conditions. The primary cause of abortion was excessive autophagic cell death (ACD) in flower buds. Blockade of autophagic flux in lotus flower buds consistently resulted in low levels of ACD and improved flowering ability under shaded conditions. Further evidence highlights the importance of the NnSnRK1-NnATG1 signalling axis in inducing ACD in lotus flower buds and culminating in their timely abortion. Under shaded conditions, elevated levels of NnSnRK1 activated NnATG1, which subsequently led to the formation of numerous autophagosome structures in lotus flower bud cells. Excessive autophagy levels led to the bulk degradation of cellular material, which triggered ACD and the abortion of flower buds. NnSnRK1 does not act directly on NnATG1. Other components, including TOR (target of rapamycin), PI3K (phosphatidylinositol 3-kinase) and three previously unidentified genes, appeared to be pivotal for the interaction between NnSnRK1 and NnATG1. This study reveals the role of autophagy in regulating the abortion of lotus flower buds, which could improve reproductive success and act as an energy-efficient measure in plants.

Benefits of Cross-Pollination in Vegetable Soybean Edamame

Dependence on cross-pollination varies widely among wild and cultivated plant species. Even among crops that are less dependent on outcrossing, such as soybean (Glycine max L.), cross-pollination can improve fruit quality and commercial value. There is a growing body of literature regarding the role of insect pollination in soybean; however, there is a knowledge gap on the intersection between the reproductive system of soybean and its pollination ecology. To address this gap, we first sought to characterize the reproductive system of vegetable soybean (edamame) in terms of benefits and reliance on outcrossing using three traditional experimental pollination scenarios in field conditions: open pollination, automatic selfing (pollinator-exclusion), and hand cross-pollination (controlled crossing). We also tested whether proximity to floral supplements planted on one edge of the field affected its reproductive outputs, and surveyed the floral visitors of the crop. Overall, we found a significant increase in fruit weight among open-pollinated plants compared to those in the automatic selfing treatment, with this effect accentuated with proximity to the flower strip. Despite open pollinated flowers having 30% higher flower abortions rates compared to automatic selfing, the number of developed seeds per fruit was similar among these treatments, with open-pollination having a greater proportion of commercial grade-A fruits. Additionally, grade-A fruits in open-pollination and hand cross-pollination treatments were similar in weight, both of which were significantly heavier than those in the automatic selfing treatment. Although edamame can automatically self, our results suggest that reproductive outputs including fruit weight and number of commercial grade-A fruits are positively affected by cross-pollination and proximity to floral supplements.

The Brassica napus boron deficient inflorescence transcriptome resembles a wounding and infection response.

Oilseed rape and other crops of Brassica napus have a high demand for boron (B). Boron deficiencies result in the inhibition of root growth, and eventually premature flower abortion. Understanding the genetic mechanisms underlying flower abortion in B-limiting conditions could provide the basis to enhance B-efficiency and prevent B-deficiency-related yield losses. In this study, we assessed transcriptomic responses to B-deficiency in diverse inflorescence tissues at multiple time points of soil-grown plants that were phenotypically unaffected by B-deficiency until early flowering. Whilst transcript levels of known B transporters were higher in B-deficient samples, these remained remarkably stable as the duration of B-deficiency increased. Meanwhile, GO-term enrichment analysis indicated a growing response resembling that of a pathogen or pest attack, escalating to a huge transcriptome response in shoot heads at mid-flowering. Grouping differentially expressed genes within this tissue into MapMan functional bins indicated enrichment of genes related to wounding, jasmonic acid and WRKY transcription factors. Individual candidate genes for controlling the "flowering-without-seed-setting" phenotype from within MapMan biotic stress bins include those of the metacaspase family, which have been implicated in orchestrating programmed cell death. Overall temporal expression patterns observed here imply a dynamic response to B-deficiency, first increasing expression of B transporters before recruiting various biotic stress-related pathways to coordinate targeted cell death, likely in response to as yet unidentified B-deficiency induced damage-associated molecular patterns (DAMPs). This response indicates new pathways to target and dissect to control B-deficiency-induced flower abortion and to develop more B-efficient crops.

Flowering induction in cassava using photoperiod extension premature pruning and plant growth regulators.

Cassava (Manihot esculenta Crantz) is a vital crop for food and economic security in many regions of the world. Despite the economic and social importance of cassava, challenges persist in developing superior varieties that meet the needs of farmers in terms of agronomic performance, nutritional quality, and resistance to pests and diseases. One of the main obstacles for genetic improvement is the lack of synchronization in flowering and the abortion of young flowers, making planned crosses and progeny production difficult. Therefore, the aim of this study was to evaluate the effect of photoperiod, premature pruning, and growth regulators on cassava flowering under low-altitude conditions in Brazil. Eight cassava clones with contrasting flowering capacity were assessed in Cruz das Almas, Bahia, using two photoperiods (ambient condition and extended photoperiod with red light for 12 hours), premature pruning at the first and second branching levels (with and without pruning), and the application of growth regulators: 0.5 mM 6-benzyladenine (BA) and 4.0 mM silver thiosulfate (STS) (with and without). Plots were assessed weekly for the number of female (NFF) and male (NMF) flowers, height of the first branching (H1B, in cm), number of days to the first branching (ND1B), and the number of branching events up to 240 days after planting (NOB). The extended photoperiod did not promote an increase in the number of flowers but allowed for precocity in cassava flowering, reducing the onset of flowering by up to 35 days, and significantly increasing the number of branches, which is closely related to flowering. The use of pruning and plant growth regulators (PGR) resulted in an increase in NFF from 2.2 (control) to 4.6 and NMF from 8.1 to 21.1 flowers. Therefore, under hot and humid tropical conditions at low altitudes in the Recôncavo of Bahia, manipulating the photoperiod and using premature pruning and plant growth regulators can accelerate cassava flowering, benefiting genetic improvement programs.

The yield of common buckwheat (Fagopyrum esculentum Moench) depends on the genotype but not on the Pin-to-Thrum ratio

Common buckwheat has a complicated flowering biology. It is characterized by a strong self-incompatibility resulting from heterostyly, i.e. the occurrence of two types of flowers: Pin and Thrum, differing in the length of pistils and stamens. Fertilization occurs only as a result of cross-pollination between these morphs. Suspicions exist that the disturbed ratio between plants producing Pin and Thrum flowers (with the latter type generating more seeds) causes low seed yield. The aim of the study was to analyze: (1) the ratio between plants with Pin and Thrum morphs, (2) flower and seed production, as well as abortion of flowers, (3) the composition of nectar collected at an early flowering stage and during full flowering. The study was performed under semi-controlled and field conditions on six Polish accessions. The results indicated that under semi-controlled conditions the Pin-to-Thrum ratio was indeed disproportionate; such a phenomenon is called anisoplethy. In the field, however, the Pin-to-Thrum ratio was well-balanced (isoplethy). The plants with both morphs aborted a similar percentage of flowers and produced a comparable number of empty seeds. The number of flowers, their abortion, and ripe seed production were independent of flower type, however, they were genotypically controlled. A strong correlation between the number of flowers produced by a plant, flower abortion and the number of empty seeds was found. The percentage of aborted flowers correlated positively with the weight of ripe seeds. Nectar composition was similar for all buckwheat genotypes, but we found some differences in the amount of individual sugars depending on the blooming stage. In the majority of accessions, the nectar produced at the early blooming stage was characterized by a greater mass and volume, and contained more individual sugars than at the full-flowering stage.

Heat Stress in French Bean and Garden Pea : A Review

This review paper addresses the effect of high temperature on pea and similar legumes. The areas covered are field pea and its production, temperature stress effects on New Zealand agriculture, seed vigour which discusses hollow heart and conductivity, high temperature stress on seed germination, threshold temperature, high temperature effects on vegetative growth and reproductive development. This is followed by adaptation mechanisms for high temperature stress, and breeding strategies which cover conventional plant breeding. The quality traits refer to protein, sugars, and the effects of high temperature on the grain composition and quality. Because of various factors related to global climate change, ambient temperatures are expected to rise in the future. Heat stress, which is a serious danger to crop output in most nations, can emerge from these temperature rises. Legumes are well-known for their nutritional and health benefits, as well as their impact on agricultural sustainability. Heat stress is a problem for legume crops because it affects the morphology, physiology, and reproductive growth of the plants. As grain legume agriculture grows to warmer areas and temperature fluctuation increases owing to climate change, high-temperature stress during the reproductive stage is becoming a serious constraint for output. The reproductive stage is critical in the life cycle of all plants, and it is vulnerable to high-temperature stress because many metabolic processes are harmed at this time, resulting in lower crop yields. Flower abortion, pollen and ovule sterility, decreased fertilization, and reduced seed filling are all observed in food legumes exposed to high-temperature stress during reproduction, resulting in smaller seeds and poorer yields. Heat tolerance in major legumes can be improved through several breeding approaches to improve field performance. Understanding the processes of molecular responses to high-temperature stress necessitates the use of omics methods to uncover the pathways behind thermo-tolerance.