Higher Root Length Research Articles

Modeling Root Development of Rice (Oryza sativa L) under Varying Drought Stress

In the current era, where drought occurrences are frequent and devastating, extensive study on drought tolerance mechanisms is imperative. Root growth under water stress is a key indicator of drought tolerance. Modeling a crop's root-length under such conditions aids in predicting seminal root length (SRL) and, consequently, its tolerance level. Under consecutive stress using Poly-ethylene-glycol (PEG), root length of a landrace originating from the drought-prone area of West Bengal, India was measured through image analysis and then mathematically modulated using an equation. The highest root length under stress was predicted at 6% PEG stress which aligned with the experimental readings. On the 15th day of stress, predicted SRL values were 104.67mm and experimental values were 90.00mm. Despite some over and underestimations with a low root mean square error of 14.68 mm, the equation provides insight into root elongation trends under various stress levels, offering a basis for predicting SRL and yield capabilities under water stress for diverse crop species.

Investigation of Rooting Performance of Some Grapevine Rootstocks with Aeroponic Method

In the study, the aeroponic system examined the rooting performances of three grapevine rootstocks (110R, 1103 Paulsen, 5BB) commonly used in Türkiye. IBA was applied to grapevine cuttings to encourage rooting. Grapevine cuttings taken during the winter dormancy period were placed in the aeroponic system after the necessary pretreatments. Significant improvements were observed in root length, root number, and rooting rate during the rooting process of cuttings placed in the aeroponic system. No diseases or pests were observed during the rooting period in the daily checks. As a result of the study, the highest root length was 17.77 cm in 110R rootstock, while the lowest was 7.1 cm in 1103P rootstock. The highest rooting rate was 76.67% in a 25 ppm IBA application in 1103P rootstock and 73.33% in a 100 ppm IBA application. The lowest rooting was 10% in 110R rootstock at 100 ppm IBA application dose and in the control group. The study's results revealed the positive effects of aeroponic systems in increasing rooting performance. The advantages offered by these systems are essential in terms of sustainability and efficiency in agriculture. Considering global challenges such as climate change and the reduction of agricultural areas, aeroponic systems are expected to find wider applications in the future.

Effect of Cutting Type, Potting Media, and Irrigation Frequency on the Success of Vegetative Propagation of Iriweriya (<em>Plectranthus Zeylanicus</em> Forssk)

Plectranthus zeylanicus is an indigenous, multi-functional herb used in traditional medicine. Due to over-exploitation from the natural habitats, the species is on the verge of extinction. Therefore, commercial cultivation of the species is needed to satisfy the rising demand while protecting its genetic base. The current study was designed with three trials to identify the most suitable cutting type, potting media, and irrigation schedule for P. zeylanicus. Four distinct cutting types (tip cutting, triple nodal cutting, double nodal cutting and single nodal cutting), five different potting mixtures (topsoil: sand: compost-1:1:1, topsoil: sand: compost-1:2:1, topsoil: sand: compost-1:1:2, topsoil: compost -1:1, topsoil: compost-1:2) and four different irrigation schedules (daily watering to field capacity level, daily watering to half of the field capacity level, every other day to the field capacity level, every other day to half of the field capacity level) were used in Completely Randomized Design with ten replicates. Survival percentage (%), number of leaves, the height of the plant (cm), average length of roots (cm), average leaf area (mm2), and chlorophyll content (SPAD Unit) were measured as growth parameters. Data were analyzed using SAS software with a 5% significance levels. Highest survival percentage (95%), highest average root length (26.8 cm), average leaf area (80.5 mm2) and a higher chlorophyll content (31.1 SPAD Unit) were recorded from tip cuttings of P. zeylanicus. Furthermore, the topsoil: sand: compost-1:1:1 combination showed a higher survival percentage (90%), number of leaves (3), highest average plant height (43.9cm) and average root length (20.2 cm) with significantly (P<0.05) higher average leaf area (52.3 mm2) and chlorophyll content (31.07 SPAD Unit). Daily watering to the field capacity showed a higher survival percentage (90%), significantly higher (P<0.05) number of leaves (3.7), plant height (51.6 cm), higher root length (25.5 cm), the highest average leaf area (80.0 mm2) and chlorophyll content (32.7 SPAD Unit). Therefore, tip-cutting planted in topsoil: sand: compost-1:1:1 media can be recommended for successful propagation of P. zeylanicus.

Naturalized species drive functional trait shifts in plant communities

Despite decades of research documenting the consequences of naturalized and invasive plant species on ecosystem functions, our understanding of the functional underpinnings of these changes remains rudimentary. This is partially due to ineffective scaling of trait differences between native and naturalized species to whole plant communities. Working with data from over 75,000 plots and over 5,500 species from across the United States, we show that changes in the functional composition of communities associated with increasing abundance of naturalized species mirror the differences in traits between native and naturalized plants. We find that communities with greater abundance of naturalized species are more resource acquisitive aboveground and belowground, shorter, more shallowly rooted, and increasingly aligned with an independent strategy for belowground resource acquisition via thin fine roots with high specific root length. We observe shifts toward herbaceous-dominated communities but shifts within both woody and herbaceous functional groups follow community-level patterns for most traits. Patterns are remarkably similar across desert, grassland, and forest ecosystems. Our results demonstrate that the establishment and spread of naturalized species, likely in combination with underlying environmental shifts, leads to predictable and consistent changes in community-level traits that can alter ecosystem functions.

Larger shrubs can maintain high infiltration and evapotranspiration rates in experimental biofiltration systems impacted by high sediment loads

Biofiltration systems can fail over time due to clogging by fine sediments in stormwater. Infiltration can be maintained by plant roots, but species selection for biofiltration to date has largely been driven by pollutant removal efficiency and tolerance of conditions. As a result, plant species diversity in biofilters is typically low and dominated by sedges and rushes. Increased use of woody species could in theory improve plant diversity, aesthetic appeal, infiltration under high sediment loads and volumetric runoff reduction via higher evapotranspiration, without jeopardising nutrient pollutant removal. We tested whether shrubs could maintain infiltration and evapotranspiration in biofiltration profiles treated with a high sediment load, by comparing them with biofilters subjected to tap water without sediment. Following sediment application, biofilter columns planted with shrubs with high total biomass and total root length showed higher infiltration and evapotranspiration than those receiving tap water. These results indicate that shrub species are likely to alleviate clogging and increase stormwater retention in biofiltration systems. However, shrubs with a high root diameter also had low total biomass and total root length and showed 33–51 % lower infiltration rates after sediment application compared with those receiving tap water. As all shrubs had higher root diameters than typical sedges and rushes, we suggest that shrubs need a combination of higher total biomass, total root length and average root diameter to effectively maintain infiltration. While shrubs which maintained infiltration had traits associated with high nutrient removal, nutrient removal efficiency of shrubs needs to be quantified. Although root traits were related to maintenance of infiltration, above-ground stems likely created flow pathways through sediment which requires further investigation. Overall, selecting shrub species with high total biomass has the potential to maintain infiltration and increase evapotranspiration in biofiltration systems impacted by high sediment loads.

Effect of Various Potting Media on the Growth and Root Development of Bougainvillea (Bougainvillea spp.) Cuttings

The study aims to enhance the propagation efficiency of Bougainvillea, a popular ornamental plant, by evaluating the effects of different potting media on its growth and root development. The experiment was conducted over 180 days using Bougainvillea hardwood cuttings and was arranged in a Randomized Block Design (RBD). The study revealed that a mixture of soil, sand, FYM, and vermicompost significantly improved plant height, stem girth, number of branches, number of leaves, leaf area, root weight, and survival rate compared to other treatments, highlighting its potential as an optimal potting medium for Bougainvillea propagation.The highest root length was recorded in the combination of Soil +Sand + Rice husk (1:1:1).

Effectiveness of some novel fungicides against the sheath blight pathogen Rhizoctonia solani in rice under in vitro and in vivo conditions

Sheath blight of rice, caused by Rhizoctonia solani, is one of the most aggressive and damaging diseases in rice cultivation, leading to significant crop losses. Consequently, chemical fungicides are the most effective method to inhibit R. solani infection and control this disease. In the present study, R. solani isolate was obtained from infected rice plants, and its pathogenicity was confirmed using Koch’s postulates on 20-day-old rice seedlings at three different inoculum levels. The lowest percent disease index and disease incidence were recorded with the 1 ml pathogen inoculum suspension, while the 2 ml and 3 ml suspensions resulted in 100% disease incidence, significantly affecting plant parameters. Furthermore, five different fungicides, Duphetar Plus, Evito, Nativo, Ridomil Gold, and Shincar, were evaluated at three concentrations (10, 100, and 1000 ppm) against R. solani using poisoned food method. The results revealed that two fungicides, Shincar and Nativo, resulted in maximum mycelial growth inhibition of R. solani, whereas the other fungicides failed to inhibit the mycelial growth of the pathogen at all concentrations. Shincar and Nativo were further tested in a greenhouse setting to control pathogen infection in rice plants. These fungicides showed excellent results, reducing R. solani infection and minimizing disease incidence in treated rice plants compared to the control. The highest root length, shoot length, and plant weight were observed with Shincar, followed by Nativo. It is suggested that the use of these fungicides may reduce sheath blight disease incidence, effectively control pathogen infection, and improve plant growth parameters in field conditions.

How is tree growth rate linked to root functional traits in phylogenetically related poplar hybrids?

Fine roots play a crucial role in soil nutrient and water acquisition, significantly contributing to tree growth. Fine roots with a high specific root length (SRL) and small diameter are often considered to help trees grow fast. However, inconsistencies in the literature do not provide a clear basis on the effect of root functional traits, such as SRL or root mass density (RMD), on tree growth rate in phylogenetically related trees. Our aim was to examine relationships between tree growth rate and root functional traits, using clones displaying different growth rates in a hybrid poplar plantation located in New Liskeard, ON, Canada. Fine roots (diameter<2mm) samples were collected using soil cores at depths of 0-20, 20-40 and 40-60cm, and analyzed for morphological, chemical and architectural traits. High SRL and thin fine roots were associated with the least productive clones, which is not consistent with the root economics spectrum (RES) theory. However, the most productive clone had larger fine root diameter and higher root lignin concentrations, probably reducing root construction and maintenance costs and carbon losses. Therefore, at the 0-20 and 20-40cm depths, tree growth rates showed positive correlations with root diameter and root lignin concentrations, but negative correlations with SRL and root soluble compounds concentration. Increasing RMD at the 0-20cm depth promoted tree growth rates, showing the importance of soil exploration in the topsoil for tree growth. We conclude that fine root variation does not always follow the RES hypothesis and argue that the rapid growth rate of trees may also be driven by fine root growth in diameter and mass in phylogenetically related trees.

Residual Effect of Rice-fish Based Organic Nutrient Management Approaches on Rice Fallow Blackgram Productivity Enhancement in Cauvery Delta Zone of Tamil Nadu

Background: A field experiment was conducted during the rice fallow season of 2023 and 2024 (January to March) at Tamil Nadu Rice Research Institute (TRRI), Aduthurai, Tamil Nadu to study the residual effect of rice-fish-based organic nutrient management practices adopted in rice on succeeding blackgram grown as rice fallow. Methods: The experiment was carried out using randomized block design (RBD) with eleven treatments viz., T1- No Green manure-Rice crop alone (RDF), T2-Green manure- Rice crop alone (PSB+KSB+ZSB), T3-T2+Nanourea, T4-Green manure- Rice crop (PSB+KSB+ZSB) + Fish, T5-T4 + Nano urea,T6- Green manure- Rice crop (PSB+KSB+ZSB) + Fish + Azolla, T7-T6 + Nano urea, T8-Green manure-Rice crop (PSB+KSB+ZSB) + Fish + Duck, T9- T8+Nano urea, T10- Green manure- Rice crop (PSB+KSB+ZSB)+ Fish + Azolla + Duck, T11- T10+Nano urea. The treatments were replicated thrice. The blackgram variety ADT 6 was used as a test crop. Result: The results revealed that among the different organic nutrient management approaches followed in the rice-fish based farming system, the residual effect of Green manure- Rice (solubilizing bacteria such as PSB, KSB and ZSB) + Fish + Azolla + Duck (T10) resulted in higher plant height, DMP, LAI and SPAD value in blackgram. Similarly, the highest root length (19.43 cm), root dry weight (1.10 g), root volume (10.68 g/cc), nodule plant-1at 20 DAS (13.82) and nodule plant-1at 40 DAS (22.97) were also obtained with the same treatment. By virtue of higher growth and yield parameters, more number of pods plant-1 (26.88) and seeds pod-1 (7.73), grain yield (789 kg ha-1) and Halum yield (2136 kg ha-1) of blackgram were obtained in the residual treatment of the residual effect of Green manure- Rice (solubilizing bacteria such as PSB, KSB and ZSB) + Fish + Azolla + Duck (T10). The available soil nutrients at 20 DAS of blackgram were higher in Green manure- Rice (solubilizing bacteria such as PSB, KSB and ZSB) + Fish + Azolla + Duck (T10). Due to higher blackgram yield, the same treatment achieved higher gross return (Rs.41561 ha-1), net return (Rs.30156 ha-1) and BCR (3.64). The study also indicated that the trench (300 m3) dug in rice fields for fish rearing provided sufficient moisture for rice fallow blackgram and thereby evaded the terminal stress.

Root traits and soil legacies drive species competition outcomes

Abstract Plant competition can be affected by plant functional traits but also by differences in fitness mediated by soil microbes. Climatic conditions such as drought further influence plant competition. Yet little is known about how soil microbes and drought interact with plant species that have distinct root traits and how this influences plant competition outcomes. We grew three plant species that co‐occur in temperate grasslands in China (Stipa krylovii, Artemisia frigida, Agropyron cristatum) in monocultures and mixtures and subjected the plant combinations to five soil inocula (root‐associated soil of S. krylovii, A. frigida, A. cristatum, an equal mixture of the three root zone soils and sterilized soil) as well as to a drought treatment. The relative change in plant biomass was used to determine plant competition outcomes. The three species exhibited clear differences in competitive abilities with A. cristatum &gt; S. krylovii &gt; A. frigida, and soil inocula or the drought treatment did not change the order. The relative yield (RY) of plants was affected by soil inocula, drought and plant arrangement. The strongest competitor, A. cristatum, with high total root length, root surface area and root volume experienced more negative biotic feedback, and drought enhanced the magnitude of these negative effects. On the contrary, the most inferior competitor, A. frigida, with high specific root length tended to have neutral or positive biotic feedback, and drought had no effect. Furthermore, the RY and fitness difference (reflected as the competitive ability in the mixture) of the three species were differentially influenced by root traits and plant–soil feedback. RY of A. cristatum could be predicted by the feedback effect in the mixture, and the fitness difference was mainly related to root traits. Both RY and fitness differences of A. frigida (the weakest competitor) could be predicted by root trait differences and feedback effects. Differences in root traits were the best predictors of the intermediate competitor S. krylovii. Our study shows that competition outcomes of co‐existing species depend on root traits and species‐specific PSF effects in mixture. Future work should examine the mechanisms that explain how plant competition and soil microbial heterogeneity act in conjunction with climate change in influencing plant coexistence. Read the free Plain Language Summary for this article on the Journal blog.

In-vitro Regeneration of An Endangered Medicinal Plant Anodendron paniculatum (Apocynaceae)

Objectives: The present study aims to establish a standardized and efficient regeneration protocol for Anodendron paniculatum A. DC. (Apocynaceae) by optimizing the effect of various plant growth regulators as it is categorized globally as an endangered medicinal plant. Methods: MS medium fortified with 3% sucrose (w/v) and different concentrations of cytokinins 6-benzylamino purine (BAP), kinetin, thidiazuron either alone or in combination with auxins, indole 3-acetic acid (IAA), naphthalene acetic acid (NAA) and GA3. For the in vitro root induction, individual and healthy shoots (3-4 cm in length) were excised in the 7th week and were cultured onto basal and half-strength MS medium supplemented with various concentrations of auxins and incubated in the culture room. Findings: MS medium supplemented with thidiazuron (2.5 𝜇M) in combination with indole 3-acetic acid (2.5 𝜇M) and GA3 (1.25 𝜇M) was most effective, providing multiple shoot regeneration for 79.33% of cotyledonary leaf explants associated with a high number of shoots per explant (20.00 ± 1.15) and length of shoot (2.66 ± 0.08 cm). Whereas, the frequency of response, mean number of shoots, and respective lengths were varied with different concentrations of 6-benzylamino purine when used in combination with IAA or NAA and BAP (5.0 𝜇M) along with IAA (2.5 𝜇M) at the frequency of 47.66%. Whereas, the addition of GA3 (1.25 𝜇M) in combination with BAP (5.0 𝜇M) and IAA (2.5 𝜇M) has shown a maximum number of multiple shoot formation/explant (12.33) with length of shoot (1.53 ± 0.08 cm). MS medium supplemented with 10 𝜇M 6-benzyl amino purine and 2.5 𝜇M naphthalene acetic acid recorded the highest response (53.66%) with more number of the shoot (9.66) and length of the shoot (1.83 ± 0.03 cm) per explant. The maximum percentage of response (84.33%) was recorded at 1 2 strength MS medium with 5.0 𝜇M NAA, whereas the highest number of roots per shoot (6.66 ± 0.33) was induced at MS + 5.0 𝜇M NAA. The highest length of roots (3.66 cm) was recorded at basal MS medium fortified with 5.0 𝜇M NAA and 7.5 𝜇M NAA. Novelty: The standardized protocol method is of first of its kind, a quick and suitable approach for the high quantity production of Anodendron paniculatum with appropriate concentrations of plant growth regulators that meet thecommercial demand of endangered medicinal plants. Keywords: Anodendron paniculatum; Endangered plant; Plant growth regulators; Regeneration; Protocol standardization

Использование регулятора роста растений янтарной кислоты при укоренении одревесневших черенков сортов и форм груши

As a result of the conducted research, it was found that when treated with succinic acid, the plant growth regulator, the greatest rooting result was observed in the varieties of pear Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudelnitsa. This indicator ranged from 75.1 to 77.8%. Without the use of a plant growth regulator (from 60.0 to 65.7%), the pear varieties Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudelnitsa had the greatest rootability. According to Table 2, the highest height of increments (from 15.0 to 15.6 cm) when treated with plant growth regulator succinic acid were characterized by pear varieties Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudelnitsa. The largest diameter of the conditional root neck when using the plant growth regulator succinic acid was characterized by the varieties of pear Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudesnitsa. This figure was 1.4 cm. The largest number of roots (from 8.0 to 8.6 pcs.) when treated with plant growth regulator succinic acid were the varieties of pear Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudelnitsa. When using the plant growth regulator succinic acid, the pear varieties Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudesnitsa had the highest root length (from 11.0 to 11.6 cm). Without the use of a plant growth regulator, the highest growth height (from 13.0 to 13.8 cm) was characterized by the varieties of pear Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudelnitsa. The largest diameter of the conditional root neck without treatment with a plant growth regulator was possessed by the pear varieties Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudelnitsa. This figure was 1.2 cm. Without the use of a plant growth regulator, the varieties Grushisvetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudesnitsa had the largest number of roots (from 6.0 to 6.5 pcs.). The largest root length (from 8.0 to 8.7 cm) without the use of a plant growth regulator was characterized by pear varieties Svetlyanka (k), Memory Yakovleva, Yakovlevskaya, Chudelnitsa.

Genetic mapping of regions associated with root system architecture in rice using MutMap QTL-seq

The root system architecture is an important complex trait in rice. With changing climatic conditions and soil nutrient deficiencies, there is an immediate need to breed nutrient-use-efficient rice varieties with robust root system architectural (RSA) traits. To map the genomic regions associated with crucial component traits of RSA viz. root length and root volume, a biparental F2 mapping population was developed using TI-128, an Ethyl Methane Sulphonate (EMS) mutant of a mega variety BPT-5204 having high root length (RL) and root volume (RV) with wild type BPT-5204. Extreme bulks having high RL and RV and low RL and RV were the whole genome re-sequenced along with parents. Genetic mapping using the MutMap QTL-Seq approach elucidated two genomic intervals on Chr.12 (3.14–3.74 Mb, 18.11–20.85 Mb), and on Chr.2 (23.18–23.68 Mb) as potential regions associated with both RL and RV. The Kompetitive Allele Specific PCR (KASP) assays for SNPs with delta SNP index near 1 were associated with higher RL and RV in the panel of sixty-two genotypes varying in root length and volume. The KASP_SNPs viz. Chr12_S4 (C→T; Chr12:3243938), located in the 3’ UTR region of LOC_Os12g06670 encoding a protein kinase domain-containing protein and Chr2_S6 (C→T; Chr2:23181622) present upstream in the regulator of chromosomal condensation protein LOC_Os2g38350. Validation of these genes using qRT-PCR and in-silico studies using various online tools and databases revealed higher expression in TI-128 as compared to BPT- 5204 at the seedling and panicle initiation stages implying the functional role in enhancing RL and RV.

Influence of Iba Concentrations on in Vitro Rooting of Cucumber Varieties

In vitro root induction was observed in cucumber as influenced by varieties and IBA concentrations. Four cucumber varieties viz. Shila, Green Field, Shital and Shahi-50 and three IBA concentrations viz. 0.0 (Control), 1.0, and 2.0 mg l-1 were used in this investigation. The Shital variety with in maximum number and the highest percentage of shoot produced roots. No root induction was observed when medium was auxin free. Higher concentration of IBA resulted in higher number (3.94) and percentage (98.65 %) of root. Half strength MS medium when fortified with 2.0 mg l-1 IBA took minimum time (6.88 days). Combined effect of varieties and IBA concentrations were found significant in all the parameters studied. The highest number (19.54) of roots were obtained from variety Shital when they were interacted with higher IBA concentration (2.0 mg l-1) followed by the interaction of same variety with lower concentration (19.18). The highest root length (8.80 cm) was found in the interaction of Shila x 2.0 mg l-1 IBA and the lowest root length (6.31 cm) was found in the interaction of Shahi-50 x 1.0 mg l-1 IBA. The Chittagong Univ. J. B. Sci.,Vol. 7(1 &amp;2):01-10, 2012

High frequency in vitro multiplication of polygonatum verticillatum (l.) All. From rhizome bud explants

This work aims to develop a rapid protocol for the in vitro establishment of Polygonatum verticillatum (L.) All., an astounding medicinal herb of Astavarga group of plants. Successful in vitro establishment was achieved utilizing rhizome bud segments of approx. 0.5 to 1.0 cm size as explants. Sterilized explants were cultured on MS medium containing graded concentration of different plant growth regulators used either singly or in various combinations. Maximum (85±10.0%) per cent shoot induction with maximum shoot length (6.50 ± 0.11cm) were recorded in TDZ (2.0 mg/l) + NAA(1.0 mg/l) + GA3 (2.0 mg/l) supplemented MS medium. NAA (1.0 mg/l) + Kn (0.5 mg/l) and IBA(1.0 mg/l) supplemented full strength MS medium with 3% sugar showed highest 70 ± 5.0% rooting response.½ MS+1.5 % sucrose medium augmented with IBA (1.0mg/l) showed the maximum average number of roots per explants (12.8 ± 1.07) with highest root length(6.12±0.27 cm). After hardening plantlets were transferred to pots in glasshouse produced healthy plants with 56% survival rate. Bangladesh J. Bot. 53(1): 203-208, 2024 (March)

Genetic Assessment of Germplasms for Anaerobic Germination in Rice

The present study was planned using portray method to screen rice germplasm lines for anaerobic germination (AG) by assessing seedling parameters. Among 266 lines studies, 121 exhibited variable germination % of 100‒17 under AG condition. Germplasm lines viz., RDR 7555, WGL 915, CSR 27, RGP 103, IRTON 103, IET 23993, RGP 60 and MTU NS1 were with highest germination capability (100%). Longest seedling length was recorded in WGL 915 (33.1 cm), RGP 57 (31.8 cm) and CSR 27 (31.2 cm). Seedling vigour index was maximum in lines WGL 915 (3310), RGP 57 (3180) and CSR 27 (3120). Genotypes CSR 27 (22.5 cm), WGL 915 (23.3 cm), RGP 57 (23.1 cm), RGP 103 (21.5 cm) and IRTON 103 (20.7 cm) are possessing highest tolerance to AG conditions with elongated shoot length. Highest root length was recorded in WGL 915 (9.8 cm), CSR 27 (8.7 cm), RGP 57 (8.7 cm), Indursamba (8.5 cm) and RGP 103 (8.1 cm). Highest heritability, genetic advance, PCV and GCV were recorded for seedling vigour index clearly highlights the importance of trait for simple selection. Highest significant positive correlation was observed between the seedling length and seedling vigour index (0.93**) followed by germination % and seedling vigour index (0.88**). Seedling length and germination % are important traits for seedling establishment in direct seeded rice under AG conditions. The 121 Germplasm lines were grouped into four clusters, cluster 3 and 4 has genotypes with above standard germination % (80%), highest seedling length (33.1‒20.3 cm) and high vigour index (3310‒2030). Present day task for plant breeders is to identify rice germplasm lines tolerant for anaerobic germination and to introgress the trait into the superior variety for development of rice pre-breeding lines with tolerance to anaerobic conditions and high yield [1].

Effect of Water Sources on the Growth Performance and Chlorophyll Content of Azolla pinnata R.Br.

&#x0D; &#x0D; &#x0D; Azolla pinnata R.Br. is an aquatic fern that grows on the surface of water bodies. The unique quality of A. pinnata is its symbiotic relationship with a prokaryotic cyanobacterium (Anabaena azollae), which confers a high rate of nitrogen fixation. It is important to find the growing conditions of Azolla in different water sources for its optimum biomass production for different usages such as biofertilizers, animal feeds, water purification and biofuel production. This preliminary study was conducted to investigate the effect of water sources on the growth performance (shoot biomass, root biomass, root length), and the chlorophyll content of Azolla. Presence of Anabaena in Azolla fronds was monitored by light microscope and number of filaments were counted per leaflet. The experiment utilized three types of water sources (tap water as control (T1), lake water (T2) and cattle manure mixed tap water (T3), in plastic buckets with 40 cm in diameter and 25 cm in height. Each treatment was triplicated in a completely randomized design and total biomass was collected weekly. Data were statistically analyzed using Minitab 17. The highest biomass of Azolla was obtained in T3 from the first week until 8th week and it was higher from T1 and T2. The highest chlorophyll content was obtained in T3 (6.4 SPAD value) showed a significant difference from T1 and T2 (p&lt;0.05). The dry weight of roots and root length in T1 showed a significant difference from T2 and T3 (p&lt;0.05). The highest root length was observed as 5 cm in T1 indicating that roots may be in search of nutrients and the lowest root length was observed as 0.8 cm in T3 with high nutrient concentrations in water. The highest number of Anabaena was observed in the leaflet of Azolla fronds in T3 which in turn increase N content in Azolla plants. It reveals that application of cattle manure in tap water significantly affects the plant biomass and the chlorophyll content of Azolla. Further studies are needed to conduct in large scale growing facilities with different nutrient concentrations of water sources to find sustainable and optimum growing conditions for Azolla and the nutrient concentrations of the plants.&#x0D; Keywords: Azolla, Chlorophyll, Growth performance, Water sources&#x0D; &#x0D; &#x0D;

Isolation of Phosphate Solubilizing Fungi from Soil and Their Application in Plant Growth Promotion

Phosphorus plays a significant role in numerous physiological and metabolic processes in plants. Soil phosphorus is immobilized due to the formation of insoluble complexes. The use of efficient phosphate-solubilizing microorganisms opens up a new prospect for better crop productivity and for greater yield performance without affecting the soil health. Phosphate-solubilizing fungi (PSF) enhance available phosphorus released from soil, which contributes to P requirement of plants. Hence, the present study was designed to evaluate the utilization of PSF as a biofertilizer. Pikovskaya's Agar medium was used to isolate fungal species from compost and open dumpsite soil. Isolated fungi were labelled as PSF-X, PSF-Y, and PSF-Z. A pot experiment was carried out to determine the effect of isolated fungal strains. The isolated fungal strain was introduced to the developed potting media which contained compost and soil at 1:1 ratio. Soya bean was selected as the experimental plant. Plant growth parameters (shoot length and root length) were measured to determine the effect of isolated fungal strains. Plant growth parameters were recorded after 21days. Fungi inoculated pots showed a significant increase in both shoot and root lengths in comparison to the control (n=9, p&lt;0.05). Potting media consisting of PSF-X showed the best result. The highest root length (4.7±0.1 cm) and shoot length (35.8±1.2 cm) were recorded in pots inoculated with PSF-&#x0D; &#x0D; Hence, isolated PSF-X, PSF-Y, and PSF-Z are recommended as suitable biofertilizer strains for potting medium.&#x0D; &#x0D; &#x0D; Keywords: Fertilizer, Fungi strain, Phosphorus, Plant growth

Effect of GA3 and Potassium on Growth and Yield in Red Radish (Raphanus sativus L.) under Subtropical Conditions of Jammu

An experiment was carried out at Vegetable Experimental Farm, Division of Vegetable Science, SKUAST Jammu during Rabi season of 2022-2023. The experiment was laid out under factorial RBD design with three replications comprising of sixteen treatments. The treatments consisted of four doses of Potassium i.e., 40, 50, 60 and 70 kg/ha and four concentrations viz. 0,100,200 and 300 ppm of GA3. The growth and yield parameters maximum viz. shoot length (34.15 cm), root length (18.73 cm), number of leaves/root (14.30), root weight (220.49 g), shoot weight (119.47 g), root- shoot ratio (2.04), fresh root shoot yield (112.42 q/ha) were recorded with 200 ppm GA3 application. Similarly, highest shoot length (29.06 cm), root length (17.53 cm), number of leaves/root (11.18), root weight (171.67 g), shoot weight (104.84 g), root-shoot ratio (1.87), fresh root shoot yield (92.31 q/ha), were recorded with 50kg/ha K2O application. However; highest root length (19.20 cm), number of leaves/root (14.87), root weight (226.14 g), shoot weight (123.54 g), root-shoot ratio (2.10), fresh root shoot yield (115.90 q/ha) were recorded with treatment combination G3K2 (200 ppm GA3 + 50 K2O/ha). Based on the investigation, it can be concluded that the application of 200 ppm GA3 at 30 days after sowing with 50 kg potassium/ha resulted in the highest growth parameters and yield.

Heavy Metal Co-Resistance with Antibiotics amongst Plant Growth Promoting Bacteria Isolates from Rhizosphere of Nypa Fruticans

Heavy metal co-resistance with antibiotics has the potential to amplify antimicrobial resistance genes in the environment, and this could have an impact on clinical settings. This study aimed to investigate the presence of heavy metal co-resistance with antibiotics among plant growth promoting bacterial isolates from the rhizosphere of Nypa fruticans. The heavy metals content of the water habouring the Nypa fruticans including copper(0.07mg/L), chromium (2.3 mg/L), lead (4.22 mg/L), iron (12.4 mg/L), cadmium (0.45 mg/L), nickel (3.12 mg/L), arsenic (0.47 mg/L) and zinc (5.37 mg/L) were above acceptable limits of WHO. A total of 10 bacteria including Bacillus subtilis, Bacillus cereus, Pseudomonas fluorescens, Klebsiella oxytoca, Serratia marcescens, Achromobacter denitrificans, Bulkholderia vietnamiensis and Azospirrilum brasilense, Azobacter vinelandii and Enterobacter aerogenes were isolated and identified to specie level using 16s RNA gene sequences, which showed above 95 % similarity with reference sequences from GenBank. The isolates showed high resistance to lead, chromium and zinc. Most of the isolates were resistant to streptomycin, ciprofloxacin and augmentin. Also, most of the isolates demonstrated positive growth promoting activities of indole acetic acid production, nitrogen fixation, siderophore production and phosphate solubilization. Pot trials on the effect of heavy metal and antibiotic tolerant bacteria on growth of beans (Phaseolus vulgaris l.) in heavy metal polluted soil revealed that beans treated with consortiumof all the isolates recorded high shoot and root length. Hence these isolates can be used for bioremediation of metal polluted site and as well act as plant growth promoting bacterial in agricultural system.