Early Flowering Research Articles

The receptor kinase OsANX limits precocious flowering and inflorescence over-branching and maintains pollen tube integrity in rice

CrRLK1L subfamily members are involved in diverse growth- and development-related processes in Arabidopsis. However, the functions of their counterparts in rice are unknown. Here, OsANX expression was detected in developing inflorescences, mature pollen grains, and growing pollen tubes, and it was localized to the plasma membrane in pollen grains and tobacco epidermal cells. Homozygous osanx progeny could not be segregated from the CRISPR/Cas9-edited mutants osanx-c1+/- and osanx-c2+/-, and such progeny were segregated only occasionally from osanx-c3+/-. Further, all three alleles showed osanx male but not female gamete transmission defects, in line with premature pollen tube rupture in osanx-c3. Additionally, osanx-c3 exhibited precocious flowering, excessively branched inflorescences, and an extremely low seed setting rate of 1.4 %, while osanx-c2+/- and osanx-c3+/- had no obvious defects in inflorescence development or the seed setting rate compared to wild-type Nipponbare (Nip). Consistent with this, the complemented line pPS1:OsANX-GFP/osanx-c2 (PSC), in which the lack of OsANX expression was inflorescence-specific, showed slightly earlier flowering and overly-branched panicles. Multiple inflorescence meristem transition-related and inflorescence architecture-related genes were expressed at higher levels in osanx-c3 than in Nip; thus, they may partially account for the aforementioned mutant phenotypes. Our findings broaden our understanding of the biological functions of OsANX in rice.

Studies on genetic variability and character association in brinjal (Solanum melongena L.)

The present investigation entitled with studies on genetic variability and character association in brinjal (Solanum melongena L). The experiment was carried at Horticulture complex, Department of Horticulture, College of Agriculture, Jabalpur (Madhya Pradesh.The experiment was laid out in Randomized Complete Block Design with three replications and each replication consisted of 20 genotypes. The results revealed that the Genotype 2013/BRBWRES-4 recorded the maximum plant height. The maximum branches per plant (9.24) were recorded in genotype SM-6-7. Early flowering was observed in Kashi Tarun (C) (26.33 days).Genotype Kashi Tarun was earliest for days to first picking. Maximum length of fruiting period was observed in genotype 2013/BRLVAR-2 (105.00 days). Genotype 2013/BRLVAR-4 produced considerably more 3.11 flowers per cluster. Maximum number of fruits per cluster was observed in 2013/BRLVAR-4 (2.88), The maximum number of fruits per plant was observed in 2013/ BRLVAR-5,Genotype 2013/BRBWRES-2 produced considerably long fruit (25.52), Genotype 2013/BRBWRES-2 produced considerably long fruit (25.52), Fruit width was recorded maximum in 2013/BRLVAR-3 (6.51 cm), The heaviest fruit were observed in genotype 2013/BRBWES-4 (168.46 g). Highest days were observed in genotype Arka Nidhi (RC) (185). Highest days were observed in genotype Arka Kusumkar (SC) (235.00), Maximum fruit yield per plant was recorded in genotype 2013/BRBWRES-1 (1235.00 g),The maximum fruit yield was recorded in genotype 2013/BRBWRES-1 (458.49 q/ha).

Analysis of a Plant’s Response to Climate Change Factors Through the Use of Herbarium Records: Collinsia violacea Nutt. (Plantaginaceae).

Climate change has resulted in various changes to the phenology of species, and some of these changes have been documented through the use of herbarium specimens. Understanding how plants react to changes in the environment can give scientists insight into how plants have been responding and will respond to the continuing consequences of climate change as well as how to approach biodiversity conservation. In this study, herbarium records of Collinsia violacea Nutt. ranging from 1895 to 2014 were utilized to show the trends of the first and peak flowering dates with regard to various geographic and climatic variables using regression analysis. The results from simple linear regression analyses showed a trend of the flowering times for first and peak flowering dates occurring earlier over the years; however, the relationship was not significant. The multiple linear regression full model for first flowering indicated increases in latitude, longitude, and mean monthly temperatures were associated with delayed flowering while increases in monthly minimum and maximum temperatures were associated with earlier flowering. The full model for peak flowering showed that peak flowering was delayed with increases in latitude, longitude, and maximum monthly temperature. The reduced models, with highly correlated variables removed, indicated significant delays in first flowering and peak flowering with increases in latitude, longitude, and mean monthly temperature, but no significant relationship between monthly precipitation and flowering time. Further research is needed to fully understand the implications of these changes.

Current and Future Effects of Climate Change on Airborne Allergens.

Delineation of the impact of elevated carbon dioxide and concomitant global warming on airborne allergens is performed. European tree pollen trends in general showed earlier start and end dates and increased total pollen release, with some differences both in locale and among species. Earlier flowering was also seen with grasses and weeds. In the case of some boreal trees, flowering was delayed due to a pre-seasonal requirement for necessary accumulated chilling temperature to achieve bud-set. Anthropogenic climate change induced rise in temperature and CO2 levels has resulted in demonstrable increases in aeroallergens. This has been most dramatic in tree pollen annual load, but also seen with grasses and weeds. Collected data is greatest for the Northern Hemisphere, especially the European continent, with supporting data from North America and Australia.

Floral thermal biology in relation to pollen thermal performance in an early spring flowering plant.

The floral microenvironment impacts gametophyte viability and plant-pollinator interactions. Plants employ mechanisms to modify floral temperature, including thermogenesis, absorption of solar radiation, and evaporative cooling. Whether floral thermoregulation impacts reproductive fitness, and how floral morphological variation mediates thermoregulatory capacity are poorly understood. We measured temperature of the floral microenvironment in the field and tested for thermogenesis in the lab in early spring flowering Hexastylis arifolia (Aristolochiaceae). We evaluated whether thermoregulatory capacity was associated with floral morphological variation. Finally, we experimentally determined the thermal optimum and tolerance of pollen to assess whether thermoregulation may ameliorate thermal stress to pollen. Pollen germination was optimal near 21 °C, with a 50% tolerance breadth of ~18 °C. In laboratory conditions, flowers exhibited thermogenesis of 1.5-4.8 °C for short intervals within a conserved timeframe (08:00-09:00 h). In the field, temperature inside the floral tube often deviated from ambient - floral interiors were up to 4 °C above ambient when it was cold, but some fell nearly 10 °C below ambient during peak heat. Flowers with smaller openings were cooler and more thermally stable than those with larger openings during peak heat. Thermoregulation maintained a floral microenvironment within the thermal tolerance breadth of pollen. Results suggest that H. arifolia flowers have a stronger capacity to cool than to warm, and that narrower floral openings create a distinct floral microenvironment, enhancing floral cooling effects. While deviation of floral temperature from ambient conditions maintains a suitable environment for pollen and suggests an adaptive role of thermoregulation, we discuss adaptive and nonadaptive mechanisms underlying floral warming and cooling.

A review on strategies for crop improvement against drought stress through molecular insights.

The demand for food goods is rising along with the world population growth, which is directly related to the yield of agricultural crops around the world. However, a number of environmental factors, including floods, salinity, moisture, and drought, have a detrimental effect on agricultural production around the world. Among all of these stresses, drought stress (DS) poses a constant threat to agricultural crops and is a significant impediment to global agricultural productivity. Its potency and severity are expected to increase in the future years. A variety of techniques have been used to generate drought-resistant plants in order to get around this restriction. Different crop plants exhibit specific traits that contribute to drought resistance (DR), such as early flowering, drought escape (DE), and leaf traits. We are highlighting numerous methods that can be used to overcome the effects of DS in this review. Agronomic methods, transgenic methods, the use of sufficient fertilizers, and molecular methods such as clustered regularly interspaced short palindromic repeats (CRISPRs)-associated nuclease 9 (Cas9), virus-induced gene silencing (VIGS), quantitative trait loci (QTL) mapping, microRNA (miRNA) technology, and OMICS-based approaches make up the majority of these techniques. CRISPR technology has rapidly become an increasingly popular choice among researchers exploring natural tolerance to abiotic stresses although, only a few plants have been produced so far using this technique. In order to address the difficulties imposedby DS, new plants utilizing the CRISPR technology must be developed.

First Report of Bacterial Leaf Spot Disease on Sesame (Sesamum indicum L.) Caused by Pseudomonas syringae pv. sesami in North Carolina.

In July 2022, dark brown to black, angular, water-soaked lesions were observed on sesame leaves (Sesamum indicum L.) in a research plot established to assess yield potential for eight varieties at the North Carolina (NC) Sandhills Research Station (Chavez 2023). Symptoms were indicative of a bacterial leaf spot (BLS). At early flowering stage, leaf spots were present on scattered plants; varieties ES108, SS3301, and ES201 exhibited up to 75% disease prevalence, with lower frequency in ES103, S39, S4302, S3251, and S3276. Symptomatic leaves from 3-4 plants were collected on four different dates from July through September. A section of symptomatic tissue was excised and macerated in sterile deionized water (SDW). A 10 µL aliquot was streaked onto SPA medium (15 g sucrose, 5.0 g proteose peptone, 0.50 g MgSO4 7H2O, 0.25 g K2HPO4, 15 g agar per liter of SDW) and incubated at 28ºC. After 72 h, numerous, smooth, white-cream colored, convex-shaped, colonies were individually isolated. Five randomly selected isolates from the different collection dates, designated as AHP108-AHP111 and AHP116, were genotyped. The 16S rRNA, gyrB, rpoD, and gapA genes were sequenced (Heuer et al. 1997; Hwang et al. 2005) and deposited to NCBI (GenBank Accessions: P213467- PP213470; OQ628040-OQ628042; PP214983-PP214994; and PP255798). These five isolates shared 100% sequence identity for gyrB and rpoD. AHP108-AHP111 shared 100% sequence identity for 16S rRNA and gapA, with 99.7% and 90.8% identity, respectively, for AHP116. A phylogenetic tree was inferred from a maximum-likelihood analysis of concatenated gyrB, rpoD, and gapA sequences of the five isolates and the top 11 hts from a blastn search of the NCBI nucleotide database. Those hits included closely related sequences from Pseudomonas syringae pv. sesami type strains ICMP 763T and ICMP 7459T. Based on this phylogenetic analysis AHP108-AHP111 and AHP116 are P. syringae pv. sesami. Recent genomic analysis suggests this pathovar is part of P. amygdali (Gomila et al. 2017), but an official name change has not been proposed. Each of the five isolates were infiltrated into leaves of sesame varieties ES108, ES103, and S327, consistently resulting in similar symptoms. Thus, strain AHP116, as a representative, was used to fulfill Koch's postulates using five, 30-day-old potted sesame plants (var. S3301). Plants were spray-inoculated with a bacterial suspension of ~108 CFU/ml until runoff; plants were incubated in moist chambers 24 h pre and post inoculation at 28ºC with 80% relative humidity and a 12 h photoperiod. At 13 days post inoculation, symptoms resembling those on plants at the Sandhills Research Stations in 2022 were evident. Reisolated bacteria were confirmed to be AHP116 through 16S rRNA and gyrB amplification and sequencing. No symptoms were observed on the five water-inoculated plants. BLS of sesame has been reported in Asia and is thought to be seedborne (Firdous et al. 2009; Prathuangwong and Yowabutra 1997). To our knowledge, this is the first report of P. syringae pv. sesami causing BLS on sesame in North Carolina. Sesame cultivation in the state increased from approximately 2,000 acres in 2022 to 13,000 acres in 2023 and there is interest in cultivating sesame as a rotational and alternative crop because it requires minimal input costs. Potential outbreaks of BLS in this warm, humid region could negatively affect sesame production, where little is known about the economic impact of the disease.

CRISPR/Cas9-mediated mutagenesis of FT/TFL1 in petunia improves plant architecture and early flowering

Petunias are renowned ornamental species widely cultivated as pot plants for their aesthetic appeal both indoors and outdoors. The preference for pot plants depends on their compact growth habit and abundant flowering. While genome editing has gained significant popularity in many crop plants in addressing growth and development and abiotic and biotic stress factors, relatively less emphasis has been placed on its application in ornamental plant species. Genome editing in ornamental plants opens up possibilities for enhancing their aesthetic qualities, offering innovative opportunities for manipulating plant architecture and visual appeal through precise genetic modifications. In this study, we aimed to optimize the procedure for an efficient genome editing system in petunia plants using the highly efficient multiplexed CRISPR/Cas9 system. Specifically, we targeted a total of six genes in Petunia which are associated with plant architecture traits, two paralogous of FLOWERING LOCUS T (PhFT) and four TERMINAL FLOWER-LIKE1 (PhTFL1) paralogous genes separately in two constructs. We successfully induced homogeneous and heterogeneous indels in the targeted genes through precise genome editing, resulting in significant phenotypic alterations in petunia. Notably, the plants harboring edited PhTFL1 and PhFT exhibited a conspicuously early flowering time in comparison to the wild-type counterparts. Furthermore, mutants with alterations in the PhTFL1 demonstrated shorter internodes than wild-type, likely by downregulating the gibberellic acid pathway genes PhGAI, creating a more compact and aesthetically appealing phenotype. This study represents the first successful endeavor to produce compact petunia plants with increased flower abundance through genome editing. Our approach holds immense promise to improve economically important potting plants like petunia and serve as a potential foundation for further improvements in similar ornamental plant species.

Genetic Variability and Cause-Effect Relationship in Aromatic Rice

Twenty diverse rice genotypes, mostly aromatic landraces, were grown during warm wet season of 2022 to analyse the genetic variability, correlation and path coefficients for sixteen agro-morphological characters. The results of genotypic and phenotypic coefficients of variability, heritability, and genetic advance indicated that improvement through selection for flag leaf angle, panicle exertion, secondary branches per panicle, test weight, spikelet number, and number of filled grains would be effective. Correlation coefficients of grain yield with flag leaf area, spikelet fertility percentage, test weight and harvest index were positive and significant, while with flag leaf angle it was negative and significant indicating the importance of these characters on grain yield. Path analysis revealed that selection for larger flag leaf area, greater test weight and narrow flag leaf angle, reduced plant height and early flowering would increase grain yield. However, restrictions are required to be imposed on panicle number, panicle length and filled grain, so that a balance between morphological architecture and physiological rhythm is maintained to optimize source-sink relationship.

Identification of superior haplotypes for flowering time in pigeonpea through candidate gene-based association study of a diverse minicore collection.

In current study candidate gene (261 genes) based association mapping on 144 pigeonpea accessions for flowering time and related traits and 29 MTAs producing eight superior haplotypes were identified. In the current study, we have conducted an association analysis for flowering-associated traits in a diverse pigeonpea mini-core collection comprising 144 accessions using the SNP data of 261 flowering-related genes. In total, 13,449 SNPs were detected in the current study, which ranged from 743 (ICP10228) to 1469 (ICP6668) among the individuals. The nucleotide diversity (0.28) and Watterson estimates (0.34) reflected substantial diversity, while Tajima's D (-0.70) indicated the abundance of rare alleles in the collection. A total of 29 marker trait associations (MTAs) were identified, among which 19 were unique to days to first flowering (DOF) and/or days to fifty percent flowering (DFF), 9 to plant height (PH), and 1 to determinate (Det) growth habit using 3years of phenotypic data. Among these MTAs, six were common to DOF and/or DFF, and four were common to DOF/DFF along with the PH, reflecting their pleiotropic action. These 29 MTAs spanned 25 genes, among which 10 genes clustered in the protein-protein network analysis, indicating their concerted involvement in floral induction. Furthermore, we identified eight haplotypes, four of which regulate late flowering, while the remaining four regulate early flowering using the MTAs. Interestingly, haplotypes conferring late flowering (H001, H002, and H008) were found to be taller, while those involved in early flowering (H003) were shorter in height. The expression pattern of these genes, as inferred from the transcriptome data, also underpinned their involvement in floral induction. The haplotypes identified will be highly useful to the pigeonpea breeding community for haplotype-based breeding.

Employing Genomic Tools to Explore the Molecular Mechanisms behind the Enhancement of Plant Growth and Stress Resilience Facilitated by a Burkholderia Rhizobacterial Strain.

The rhizobacterial strain BJ3 showed 16S rDNA sequence similarity to species within the Burkholderia genus. Its complete genome sequence revealed a 97% match with Burkholderia contaminans and uncovered gene clusters essential for plant-growth-promoting traits (PGPTs). These clusters include genes responsible for producing indole acetic acid (IAA), osmolytes, non-ribosomal peptides (NRPS), volatile organic compounds (VOCs), siderophores, lipopolysaccharides, hydrolytic enzymes, and spermidine. Additionally, the genome contains genes for nitrogen fixation and phosphate solubilization, as well as a gene encoding 1-aminocyclopropane-1-carboxylate (ACC) deaminase. The treatment with BJ3 enhanced root architecture, boosted vegetative growth, and accelerated early flowering in Arabidopsis. Treated seedlings also showed increased lignin production and antioxidant capabilities, as well as notably increased tolerance to water deficit and high salinity. An RNA-seq transcriptome analysis indicated that BJ3 treatment significantly activated genes related to immunity induction, hormone signaling, and vegetative growth. It specifically activated genes involved in the production of auxin, ethylene, and salicylic acid (SA), as well as genes involved in the synthesis of defense compounds like glucosinolates, camalexin, and terpenoids. The expression of AP2/ERF transcription factors was markedly increased. These findings highlight BJ3's potential to produce various bioactive metabolites and its ability to activate auxin, ethylene, and SA signaling in Arabidopsis, positioning it as a new Burkholderia strain that could significantly improve plant growth, stress resilience, and immune function.

Flowering, Quality and Nutritional Status of Tropaeolum majus L. ‘Spitfire’ after Application of Trichoderma spp.

The aim of this study was to compare the influence of three species of fungi of the Trichoderma genus (T. aureoviride Rifai—Ta8, T. hamatum/Bonord/Bainier—Th15, and T. harzianum Rifai—Thr2) on the quality, flowering, and nutritional status of Tropaeolum majus L. ‘Spitfire’. Early flowering was only influenced by T. hamatum, which delayed it by 6 days. T. aureoviride, T. hamatum, and T. harzianum stimulated the flowering of the ‘Spitfire’ cultivar but did not affect the size of the flowers. The plants treated with T. harzianum after being planted in pots flowered the most abundantly. Trichoderma spp. caused the plants to grow more intensively, producing longer and more leafy shoots with a greater number of offshoots. Trichoderma spp. stimulated the uptake of macronutrients, except for phosphorus (P). In the case of calcium (Ca) and sodium (Na), this phenomenon was only observed in plants treated with T. aureoviride and T. hamatum, and for magnesium (Mg), only when T. hamatum was applied to sown seeds. As for the developed root systems, as far as the micronutrients are concerned, Trichoderma spp. stimulated the uptake of zinc (Zn) and manganese (Mn). Apart from that, there was a higher iron (Fe) content in the plants treated with T. harzianum on both dates and T. aureoviride after planting the plants in pots.

Mother-reliant or self-reliant: the germination strategy of seeds in a species-rich alpine meadow is associated with the existence of pericarps.

Some plants germinate their seeds enclosed by a pericarp, whereas others lack the outer packaging. As a maternal tissue, the pericarp might impart seeds with different germination strategies. Plants in a community with different flowering times might separately disperse and germinate their seeds; therefore, flowering time can be considered as one manifestation of maternal effects on the offspring. The mass of the seed is another important factor influencing germination and represents the intrinsic resource of the seed that supports germination. Using seeds from a species-rich alpine meadow located in the Hengduan Mountains of China, a global biodiversity hotspot, we aimed to illustrate whether and how the type of seed (with or without a pericarp) modulates the interaction of flowering time and seed mass with germination. Seeds were germinated in generally favourable conditions, and the speed of germination [estimated by mean germination time (MGT)] was calculated. We quantified the maternal conditions by separation of flowering time for 67 species in the meadow, of which 31 produced seeds with pericarps and 36 yielded seeds without pericarps. We also weighed 100 seeds of each species to assess their mass. The MGT varied between the two types of seeds. For seeds with pericarps, MGT was associated with flowering time but not with seed mass. Plants with earlier flowering times in the meadow exhibited more rapid seed germination. For seeds without a pericarp, the MGT depended on seed mass, with smaller seeds germinating more rapidly than larger seeds. The distinct responses of germination to flowering time and seed mass observed in seeds with and without a pericarp suggest that germination strategies might be mother-reliant for seeds protected by pericarps but self-reliant for those without such protection. This new finding improves our understanding of seed germination by integrating ecologically mediated maternal conditions and inherent genetic properties.

The AGL6–ELF3–FT circuit controls flowering time in Arabidopsis

ABSTRACT Adjusting the timing of floral transition is essential for reproductive success in plants. A number of flowering regulators integrate internal and external signals to precisely determine the time to flower. We here report that the AGAMOUS-LIKE 6 (AGL6) – EARLY FLOWERING 3 (ELF3) module regulates flowering in the FLOWERING LOCUS T (FT)-dependent pathway in Arabidopsis. The AGL6 transcriptional repressor promotes floral transition by directly suppressing ELF3, which in turn directly represses FT expression that acts as a floral integrator. Indeed, ELF3 is epistatic to AGL6 in the control of floral transition. Overall, our findings propose that the AGL6–ELF3 module contributes to fine-tuning flowering time in plants.

Comprehensive analysis of the Spartina alterniflora WD40 gene family reveals the regulatory role of SaTTG1 in plant development.

The WD40 gene family, prevalent in eukaryotes, assumes diverse roles in cellular processes. Spartina alterniflora, a halophyte with exceptional salt tolerance, flood tolerance, reproduction, and diffusion ability, offers great potential for industrial applications and crop breeding analysis. The exploration of growth and development-related genes in this species offers immense potential for enhancing crop yield and environmental adaptability, particularly in industrialized plantations. However, the understanding of their role in regulating plant growth and development remains limited. In this study, we conducted a comprehensive analysis of WD40 genes in S. alterniflora at the whole-genome level, delving into their characteristics such as physicochemical properties, phylogenetic relationships, gene architecture, and expression patterns. Additionally, we cloned the TTG1 gene, a gene in plant growth and development across diverse species. We identified a total of 582 WD40 proteins in the S. alterniflora genome, exhibiting an uneven distribution across chromosomes. Through phylogenetic analysis, we categorized the 582 SaWD40 proteins into 12 distinct clades. Examining the duplication patterns of SaWD40 genes, we observed a predominant role of segmental duplication in their expansion. A substantial proportion of SaWD40 gene duplication pairs underwent purifying selection through evolution. To explore the functional aspects, we selected SaTTG1, a homolog of Arabidopsis TTG1, for overexpression in Arabidopsis. Subcellular localization analysis revealed that the SaTTG1 protein localized in the nucleus and plasma membrane, exhibiting transcriptional activation in yeast cells. The overexpression of SaTTG1 in Arabidopsis resulted in early flowering and increased seed size. These outcomes significantly contribute to our understanding of WD40 gene functions in halophyte species. The findings not only serve as a valuable foundation for further investigations into WD40 genes in halophyte but also offer insights into the molecular mechanisms governing plant development, offering potential avenues in molecular breeding.

Effect of High-Tunnel and Open-Field Production on the Yield, Cannabinoids, and Volatile Profiles in Industrial Hemp (Cannabis sativa L.) Inflorescence.

This study discovered the impact of high-tunnel (i.e., unheated greenhouse) and open-field production on two industrial hemp cultivars (SB1 and CJ2) over their yield parameters, cannabinoid development, and volatile profiles. Development of neutral cannabinoids (CBD, THC, and CBC), acidic cannabinoids (CBDA, THCA, and CBCA), and total cannabinoids during floral maturation were investigated. The volatile profiles of hemp flowers were holistically compared via HS-SPME-GC/MS. Findings indicated a high tunnel as an efficient practice for achieving greater total weight, stem number, and caliper, especially in the SB1 cultivar. Harvesting high-tunnel-grown SB1 cultivars during early flower maturation could obtain a high CBD yield while complying with THC regulations. Considering the volatile profiles, hemp flowers mainly consisted of mono- and sesquiterpenoids, as well as oxygenated mono- and sesquiterpenoids. Volatile analysis revealed the substantial impact of cultivars on the volatile profile compared to the production systems.

Growth, productivity and quality of colored capsicum (Capsicum annuum L.) as influenced by hybrids and plant growth regulators under controlled environment conditions

In developing countries like India, rapid urbanisation was under way and the diet habits of the people have been changing day to day. Under this transformation, a section of the population is focused on nutritional security where vegetables play a major role in daily diet. Among different vegetables coloured bell pepper which is commonly known as capsicum, has importance due to its nutritional quality and market demand. The quality and productivity of coloured capsicum can be improved by choosing the best performing hybrids and exogenous application of plant growth regulators. Considering the above, the present study was conducted from November to April of 2020-21 and 2021-22 at the Protected Cultivation Unit of Centurion University of Technology and Management, Paralakhemundi, Odisha under controlled environment conditions. The experiment was laid out in factorial randomized block design consisting of two hybrids, namely, Orobelle (yellow colored) and Bomby (red colored); and eight treatments of growth regulators which were GA3 @ 25 ppm, GA3 @ 50 ppm, GA3 @ 75 ppm, GA3 @ 100 ppm, NAA @ 20 ppm, NAA @ 40 ppm, NAA @ 60 ppm and NAA @ 80 ppm. A total of 16 treatment combinations were worked out in the experiment which were replicated thrice. The results of the experiment revealed that there was no significant variation among the hybrids cultivated with respect to yield attributes, yield, quality parameters and growth attributes excluding plant height and number of leaves per plant at 60 DAS and 90 DAS. However, there was a significant impact of plant growth regulators on growth attributes, yield attributes, yield and quality parameters. The application of NAA @ 80 ppm resulted in early flowering (43.8 days after planting). Moreover, the maximum number of flowers per plant (32.5 flowers/plant), flower to fruit ratio (52.9), fruits per plant (19.5) and weight of the fruit (133.6 g) recorded in GA3 @ 100 ppm application. There was a significant interaction effect among treatment combinations in fruit yield where the highest value was recorded in Bomby hybrid with GA3 @ 100 PPM application. From the study it may be concluded that cultivation of both the hybrids can be considered as per the fruit colour and market demand along with the application of GA3 @ 100 ppm under controlled environment conditions.

Climate–resilient strategy for shortening the crop cycle in rice and the host influenced rhizosphere microbiome

We present the field rapid generation advancement procedure for shortening the crop cycle in rice. The practical protocol developed by us using different maturity groups of rice showed promising early flower induction. We observed a shortening of crop cycle to about 35–40 days depending on the variety. The spacing between the plants was the major influencer for flower induction compared to other interventions tested viz., clipping, potassium di-hydrogen phosphate and paclobutrazol spray. Our raised bed direct seeding strategy completely avoided the transplantation. The work flow for flower induction can be a reference to increase generations of rice breeding. The rhizosphere bacterial dynamics using 16srRNA gene amplicon sequencing showed the Acinetobacter population abundance as a key mediator and marker for flowering time. The alpha diversity at flowered and unflowered stage showed the species richness as Control < Pusa Sugandh 5 < BPT-5204. The rice rhizosphere of this ecosystem had an abundance of Methylotrophs that utilize methane as a carbon source suggesting that the developed method is a green technique suitable for generation advancement that can be replaced for flooded condition assisted breeding in rice. Selective enrichment of functional abundance between varieties suggested the host - influenced microbiome for early flowering in rice. This protocol is expected to greatly accelerate the process of new variety breeding and the construction of mapping populations.

Effect of Varieties and Dates of Sowing on Seed Yield of Sunhemp

A field experiment was conducted at Agricultural Research Stattion, Amadalavalasa to identify a suitable sunhemp variety and sowing window during Khariff or obtaining higher yields in North Coastal Andhra Pradesh. The soil of experimental site was sandy loam in texture, medium in alkaline reaction (pH: 8.24), non-saline (EC: 0.22 dS m-1), low in organic carbon (0.5%), low in available nitrogen (219.3 kg ha-1), low in available phosphorus (22.18 kg P2O5 ha-1) and medium in available potassium (268.3 kg K2O ha-1). The experiment was laid out in a split plot design with four main plot treatments, three subplot treatments and with three replications. The main treatments comprised of four dates of sowing viz., D1: 1st may,D2:15th may,D3:1st june and D4: 15th june. The sub plot treatments comprised of three varieties viz., V1: K12 yellow, V2: K12 black and V3: SH 4. All the cultural practices were adopted as per the recommendations of University. The results of the experiment indicated that growth and yield of sunhemp was significantly influenced by variety as well as date of sowing. It was evident that sowing of sunhemp in North Coastal AndhraPradesh on 15th June was optimum as it recorded shorter plant height (224.8 cm), early flowering i.e flower initiation at 80 days, 50% flowering in 91 days, higher plant population and significantly higher seed yield (2.35 q/ha) was recorded. Among the varieties tested SH 4 produced taller plants exhibited early flowering and finally recorded significantly higher seed yield (2.16 q/ha). However, plant population did not vary significantly among the varieties. Interaction between dates of sowing and varieties indicated that for seed crop K12 black and SH 4 of sunhemp can be sown between 1st june to 15th June in North Coastal Andhra Pradesh for getting higher seed yield of sunhemp as the seed yield of the above two varieties and dates of sowing were atpar.

Optimization of Flowering and Fruit Development in Ber (Ziziphus mauritiana L.) cv. Umran using Fertilizers, Micronutrients, and Bioregulators

In order to investigate the effect of fertilizers, micronutrients and bioregulators on flowering and fruit growth and developments on ber (Ziziphus mauritiana L.) cv. Umran, an experiment was carried out during 2019/2020 cropping season at the Fruit Research Station, Imalia, Department of Horticulture JNKVV Jabalpur. The study used a factorial design using randomized complete block design (RCBD), with three replications and a total of twelve treatment combinations that included bioregulators, micronutrients, and fertilizers either separately or in various combinations. The application of treatment T4 [RDF (N:P:K)+Foliar spray of GA3 + NAA (50 ppm+50 ppm)] was found to be significantly superior as compared to other treatments for flowering parameter in respect to induce early flower bud formation, based on the results obtained in this study. It takes 22 days to induce the earliest flowering after spray, and it takes 8.67 days to achieve 50% flowering. The earliest date of flower bud initiation was found with the T11 [RDF (N:P:K)+ NPK -18:18:18 (1.0%) + ZnSO4 (0.5%) + Borax (0.3%)] which showed to be the best for fruit growth and development characteristics, including specific gravity (1.047), fruit weight (36.52 g), fruit volume (36.56 ml), fruit length (4.53 cm), and fruit diameter (3.50 cm).With regard to practically every fruit growth and development attribute, the treatment T10 was found to be the second best.