Duration Rice Research Articles

TKM 15 -A High Yielding, Short Duration Rice Variety Suitable for Direct Sown Water Limited Areas of Tamil Nadu, India

TKM 15 -A High Yielding, Short Duration Rice Variety Suitable for Direct Sown Water Limited Areas of Tamil Nadu, India

Quantifying chlorophyll content index for efficient nitrogen management in rice (Oryza sativa L.)

Applying nitrogen fertilizer strategically enhances rice productivity in nitrogen-deficient soils. Splitting fertilizer doses across growth stages optimizes nutrient use efficiency. Monitoring chlorophyll levels correlates closely with leaf nitrogen content, crucial for assessing crop health. Non-destructive chlorophyll content meter techniques, such as the Chlorophyll Content Index (CCI), allow for precise nitrogen management adjustments in the field. However, its critical value may differ depending on crops and varieties. Hence, to find out the critical CCI value for rice cv. ADT 43, observational trials were conducted at the Experimental Farm of Annamalai University during two seasons Kuruvai (June-Oct 2023) and Navarai (Dec-March 2024). The pooled data of the present study indicated that the average LNC (maximum tillering, panicle initiation and booting stages) has a linear relationship (R2=0.8545) with the yield of rice crop. The corresponding higher yield ( greater than 7t/ha) coincided with LNC of 3.1%. Likewise, the average CCI has a linear relationship (R2=0.9031) with the LNC of rice plants. The corresponding LNC ( greater than 7t/ha) was matched with the CCI value of 29. This CCI value of 29 is considered as the critical CCI value. CCI can be used as a decision-support tool for N-fertilization of short duration rice crop, and when CCI reduced below this critical value the farmers can fertilise the field with adequate N.

Perception of and adaptation practices to climate change: a case study of smallholder paddy farmers in Dai Loc district of Vietnam

ABSTRACT The purpose of this study is to investigate the smallholder paddy farmers’ perceptions of climate change and identify factors that affect their perceptions of it in Vietnam. A sample size of 260 was chosen from a total of 745 smallholder paddy farmers and a structured questionnaire was constructed to gather data. Descriptive, chi-square (χ2) and logistic regression analyses were used. The research results revealed that the socio-economic characteristics of smallholder paddy farmers vary, reflecting diverse paddy-farming systems in the study area. A large number of smallholder paddy farmers noticed temperature, drought and pest/disease increased, whereas rainfall and flood decreased over the past 20 years. A high proportion of smallholders reported that more irrigation for paddy rice (82.7%), followed by growing short duration rice (65.0%) and changing paddy rice planting and harvesting date (63.1%) are the main adaptation practices. A majority of smallholders indicated that lack of information about potential climate change (67.7%), followed by lack of knowledge concerning appropriate adaptation (66.2%) and lack of market access and storage facility (64.2%) are the key barriers to adaptation practices. The success of the regression model’s overall prediction is reported by model χ2 = 81.5, p < 0.000, indicating that the explanatory variables significantly explained the dependent variable. Among the explanatory variables, agricultural practice, information and communication technology possessed, participation in rural credit programmes, participation in technical training programmes, participation in community-based organisations, gender, age, level of education, size of farm and farming experiences are significantly important determinants of smallholders’ perception of climate change.

Evaluating Panicle Architecture and Yield Characteristics in Medium Duration Rice Genotypes through Correlation and Principal Component Analysis

Panicle architecture is a crucial factor that significantly improves economic grain yield. The panicle exhibits considerable variation in its structure, including the number of branches, the length and weight of the panicle, and arrangement of the grains. These traits are not only vital for the plants reproductive efficiency but also for optimizing yield potential. This study focuses on assessing variation in panicle architecture among 31 different medium duration rice genotypes by employing principal component analysis and correlation analysis. This study aimed to dissect the complex relationship between different panicle characteristics. The findings revealed that the first three principal components together explained 60.3% of the total variability. In the first principal component (PC1), the traits SF, PBL, YPH, and HI had the highest positive eigenvalues, indicating their significant impact on overall genotype variations. The second principal component (PC2) was mainly influenced by TSP and SBN, while the third principal component (PC3) was driven by PW and SBL. These results suggest that grain yield is significantly affected by the traits SF, PBL, YPH, HI, TSP, SBN, PW, and SBL. The correlation analysis revealed that the number of secondary branches showed a positive association with unfilled spikelet. Spikelet fertility exhibited a strong positive correlation with yield hectare-1 and harvest index, highlighting its significance in overall yield improvement. Therefore, these components are crucial for differentiating rice genotypes with higher grain yield potential. By evaluating correlation and principal component analysis, we aimed to identify traits that can be targeted for crop improvement initiatives. The findings will contribute to the development of rice varieties that are better suited to specific growing conditions and have enhanced yield potential. This approach will enable the identification of key panicle architecture and yield and yield traits that optimize resource allocation and improve grain filling efficiency, ultimately leading to rice varieties with higher productivity and adaptability.

Performance of Medium Duration Rice Cultivars on Growth, Productivity and Profitability under South Andaman Condition of India

A field experiment was carried out during both July to November 2019 and 2020 on the farmers’ fields in the Guptapara village of South Andaman, India, to determine the growth and yield performance of a medium-duration rice cultivar and its suitability. The treatments included five medium-duration rice cultivars consist of Jaya, ADT 45, CARI dhan 3, CARI dhan–6, and CARI dhan-7 laid out in Randomised Complete Block Design with four replications. The results showed that medium-duration rice cultivars exhibited significant variations in growth and yield attributing characteristics, such as leaf area index, root length, root dry weight, the number of productive tillers m-2, panicle length, filled grains panicle-1, and test weight. The growth attributes of rice were significantly influenced by medium-duration rice cultivars, except plant height. Regardless of the duration of the rice cultivars, CARI dhan 7 exhibited significantly greater root length and dry weight, measuring 33.2 cm and 6.37 g hill-1, respectively. CARI dhan 7 had substantially higher productive tillers (357 m-2), filled grains panicle-1 (121.6), grain (4790 kg ha-1), and straw yield (7390 kg ha-1), which was statistically comparable to CARI dhan-6. CARI dhan 7 had the highest gross return of ` 71595 ha-1, a net return of ` 36946 ha-1, and a benefit-cost ratio of 2.07. The medium-duration rice cultivar CARI dhan 7 performed better and more suitable in low-lying areas of South Andaman.

Energy Use Efficiency of late Sown Short Duration Rice Varieties Under Different Nitrogen Management Practices

One of the major causes of low nitrogen use efficiency in rice is the application of fertilizer nitrogen (N) more than crop requirement at times when it is not required by plant during late sown conditions. This experiment was conducted at Rajendranagar farm of ICAR-Indian Institute of Rice Research, Hyderabad during kharif2021. The experiment was laid out in split plot design with three replications. Main plots consisted of three short duration rice varieties DRR Dhan-44, MTU 1010, MTU 1156 and four nitrogen management practices (sub-plots) recommended dose of nitrogen (RDN) @ 120 kg N ha-1, Silicon coated urea (SCU) @ 90 kg ha-1, Leaf Colour Chart based N application (LCC)@105 kg N ha-1, Soil test crop response based N application (STCR) @ 114.5 kg N ha-1. Among the varieties highest energy input (13.22 GJ ha-1) was recorded in DRR Dhan-44 but energy output (172.6 GJ ha-1) and energy use efficiency (10.26 GJ ha-1) were recorded in MTU 1156. Among the N management practices highest energy input (13.94 GJ ha-1) was recorded in RDN@ 120 kg N ha-1 and energy use efficiency (10.38 GJ ha-1) was recorded with Leaf colour chart based N application@105 kg Nha-1

Genetic Architecture, Studies to Identify the Selection Criteria for Yield in Long Duration Rice Lines (Oryza sativa L.)

Genetic Architecture, Studies to Identify the Selection Criteria for Yield in Long Duration Rice Lines (Oryza sativa L.)

Productivity and profitability of rice (Oryza sativa) varieties as influenced by age of seedlings in north-eastern Himalayan region

An experiment was conducted during boro (rabi) season of 2012–13 and 2013–14, at Gerua, Kamrup, Asom, India, to study the effect of different age of seedlings on growth and yield of rice (Oryza sativa L.) varieties. Ten treatment combinations of 2 different duration rice varieties, i.e. ‘Chandrama’ (175 days) and ‘Naveen’ (155 days), and 5 ages of seedlings (40, 50, 60, 70 and 80 days) were tested. ‘Chandrama’ rice recorded significantly higher grains/panicle and 1,000-seed weight as well as grain yield (5.93 and 6.50 t/ha) over ‘Naveen’ rice. Days to 50% flowering decreased with the increment in age of seedling by 2–10 days, whereas total maturity duration increased by 6–28 days. In case of age of seedlings, 40 and 50 days old seedlings showed higher values of growth and yield attributes that reflected in grain yield. There was gradual yield decrease with increment in the age of seedling due to reduced values of tillers/m2 , filled grains/panicle. The yield penalty was non-significant in case of long-duration rice variety ‘Chandrama’, while in case of ‘Naveen’, there was significant reduction in grain yield when seedling age exceeded beyond 60 days. ‘Naveen’ rice with 40 and 50 days old seedlings recorded significantly higher grain yield over 70 and 80 days seedlings respectively. Earlier farmers using their own local rice landraces which were long duration and less affected by age of seedling but with development of new semi-dwarf, medium-duration rice varieties need to be transplanted at optimum age of seedling. Thus, the age of seedling can be extended up to 60 days for those rice varieties having long duration (&gt;175 days) while for short duration (&lt;155 days), it should not be extended beyond 50 days.

A Comprehensive Molecular, Biochemical, Histochemical, and Spectroscopic Characterization of Early and Medium Duration Rice Genotypes Investigating Dry Matter Accumulation Efficiencies.

Investigation on accumulation of cell wall components over critical growth stages will surely provide a new insight into dry matter accumulation studies in rice. An elevated biomass production provides an alternative strategy of yield improvement, which in turn maneuvers the species concerned as potential dual-purpose crop. On that note, present study was carried on 33 early and 39 medium duration rice genotypes. The average cellulose accumulation was 6.51% and 8.17% in early and medium duration genotypes, respectively, at flowering stage, which later on dipped to 1.43% and 3.46%, respectively, at physiological maturity. The gene specific marker MDgsp-5.a exhibited highest estimate of polymorphic information content (PIC), i.e., 0.685, closely followed by MDgsp-6.a with polymorphic information content (PIC) of 0.683. The control genotypes, i.e., Pratap and Mandakini, are grouped under the same cluster, i.e., Cluster-I.A, indicating their inherent genetic divergence from that of potential accumulators pertaining to cellulose accumulation. Pratap and Mandakini failed to produce peaks of conspicuous form at 3342cm-1 and 1635cm-1, bearing out by their low performance pertaining to cellulose and lignin accumulation at the later stages of development, respectively. From histochemistry studies, it was observed that the cell walls of sclerenchyma, peripheral vascular bundles, and parenchyma of the culm transections in control genotypes stained lightly than that of prolific accumulator cell walls, thus corroborating the findings of compositional analysis. The variation in cell wall thickening is primarily accounted due to altered carbohydrate accumulation across the growth stages as explored under scanning electron micrograph.

Increasing Farmers Income through Demonstration of Climate Resilient Technology

The project TDC-NICRA (National Innovations on Climate Resilient Agriculture) was initiated in KVK, Dhemaji from 2021-22 in Magurmari village of Simen-Chapori Block under the District Dhemaji. The village was affected by flood every year leaving the villagers in a state of destitute. Majority of the farmers of Magurmari village were marginal farmer. Flood, irrigation, water conservation, diseases infestation on plant and occupational migration were the major problem of the village due to which crop failure occurs which leads low income of the farmers. To establish climate resilient agriculture in Magurmari village Demonstration on submergence tolerant rice variety ‘Ranjit sub-1’, medium duration rice variety Numoli, Cultivation of megha turmeric through organic mulching, cultivation of rabi vegetables using paddy straw as organic mulch and Low cost raised bed vermicompost production interventions were taken up in magurmari village. The study revealed that these climate resililient technology weer provd to be boom in magurmari village which help the farmers to increase the farm production and their income to a great extent.

Improving yield and water productivity of rice in sodic soil with saline water through drip irrigation

A field experiment was conducted at Anbil Dharmalingam Agricultural College and Research Institute, Tiruchirappalli, to determine suitable rice varieties and lateral spacing for drip irrigation in sodic soil with saline water. The experiment involved four short duration rice varieties ('ADT 36', 'ADT 45', 'TRY (R) 2', and 'Anna (R) 4' ) and four pre-release rice cultures ('TR13-069', 'TR13-083', 'TR09-27', and 'TR09-30'). Drip systems were installed with lateral spacing of 45 cm and 90 cm, and emitter/dripper spacing of 30 cm. Drippers had a discharge rate of 2.0 liters per hour, and irrigation was scheduled at 100% pan evaporation rate, applied every alternate day. The variety, ''TRY (R) 2'' produced a greater number of panicles (365/m2) and a higher percentage of tillers to panicles conversion (77%) while ''ADT 36'' exhibited a higher number of filled grains (99.5/panicle) and total grains per panicle (117.4). With respect to yield, ''TRY (R) 2'' achieved the highest grain yield of 2991 kg/ha, followed by ''ADT 36'' and ''Anna (R) 4 ''. The drip lateral spacing of 90 cm exhibited significantly higher yield compared to a spacing of 45 cm. The varieties ''ADT 36'' and ''ADT 45'' utilized 550.3 mm of irrigation water and received 283.5 mm of rainfall, while ''Anna (R) 4 '' and ''TRY (R) 2'' used a total of 871.9 mm of water, including 575.2 mm of irrigation water and 296.7 mm of rainfall. Variety ''TRY (R) 2'' demonstrated a higher water productivity of 3.58 kg/ha/mm, followed by ''ADT 36''. Based on these findings, it is recommended to grow the ''TRY (R) 2'' rice variety under drip irrigation with a lateral spacing of 90 cm in sodic soil with saline water conditions, as it showed superior performance in terms of grain yield and water productivity.

Optimizing transplanting window for higher productivity of short and medium duration rice cultivars in Punjab, India using CERES-Rice model

Optimizing transplanting window for higher productivity of short and medium duration rice cultivars in Punjab, India using CERES-Rice model

Estimating rice crop (Oryza sativa L.) parameters during the 'Yala' season in Sri Lanka using UAV multispectral indices

Remote estimation of aboveground biomass (AGB), plant height (PH), and rice yield (RY) before the actual harvest is vital for the early management of rice crops. Traditionally, on-ground spot measurements and destructive sampling methods were conducted across the field which is problematic due to poor temporal and spatial representation, time consumption, delayed crop management and inefficient input application. Thus, this study evaluates the advanced aerial multispectral imagery technique to explore the association of image-derived vegetation indices (VIs) with the ground measured AGB, PH and RY at crop season “Yala” 2021 in the controlled field and extend the relationship with the commercial farmer field data. The experiment was carried out at a controlled rice field and then at a commercial farmer field cultivated with three-month crop duration rice varieties as Bg 300 and Bg 374, respectively. Multispectral images of the field were acquired by an Unmanned Ariel Vehicle (UAV, DJI P4-multispectral, Shenzhen, China) at 25m flying height during the booting stage of the rice plant. Then VIs was derived using QGIS (version 3.16) software and analyzed to select the best combination of VIs explaining the ground measured parameters using partial least squares regression (PLS-R). According to the results, a strong agreement between growth parameters during the booting stage at 25m flight height was proven. When comparing the relationship at the commercial farmer field, the estimated AGB showed strong accuracy (R2 = 0.62, RMSE = 0.055 kg/m2) with the observed AGB using VIs (GRVI and SR). Estimated PH showed weak accuracy (R2 = 0.04, RMSE = 19.33 cm) with the observed PH using (CI red edge, TCARI and NPCI) and estimated RY showed strong accuracy (R2 = 0.75, RMSE = 817.8 kg/ha) with observed RY using VIs (TVI, SR and MSR). Therefore, this study proves an association of VIs with rice crop parameters AGB and RY in rice cultivation that can be used to measure non-destructively prior to harvest during “Yala” in Sri Lanka.

Bio-agronomic characteristics of new promising short duration rice (Oryza sativa L.) lines and varieties in Central Vietnam

Rice is an important food crop in Vietnam and facing challenges due to climate change, limited cultivation area, and limited adaptable varieties. Therefore, field experiments were carried out in two seasons of summer 2022 and spring 2023 at the Agricultural Science Institute for Southern Coastal Central of Vietnam (ASISOV), Binh Dinh province, to evaluate the growth, development and yield of new promising short duration rice lines and varieties in Binh Dinh province. Promising 10 lines and varieties namely ANS1 (control), BDR97, BDR57, BDR79, BDR87, BDR36, Line 159, Line 243, Line 64, and Line 46 were used for the study. They were arranged in a randomized block design with three replications. Research results showed that the duration of rice lines and varieties ranged from 90 to 112 days. The yield of the lines and varieties was from 5.94 to 7.44 t/ha in the summer season 2022 and 6.42 to 8.05 t/ha in the spring season 2023. The quality of rice lines and varieties was rated from average to good. Two new promising varieties were identified, including BDR79 and BDR57, with a short duration of 91-103 days, yield from 7.27-8.05 t/ha, higher than the control variety from 11.6-20.5% and belonging to good quality classification.

Increasing grain weight and yield stability by increasing pre-heading non-structural carbohydrate reserves per spikelet in short-growth duration rice

Rice yield stability is a breeding goal, particularly for short-growth duration rice, but its underlying mechanisms remain unclear. In an attempt to identify the relationship between yield stability and source–sink characteristics in short-growth duration rice, a field experiment was conducted at three sites (Yueyang, Liuyang, and Hengyang) in 2021 and 2022. This study compared yield, yield components, source–sink characteristics, and their stability between two stable-yielding short-growth duration rice cultivars, Zhongzao 39 (Z-39) and Lingliangyou 268 (L-268), and two unstable-yielding short-growth duration rice cultivars, Zhongjiazao 17 (Z-17) and Zhuliangyou 819 (Z-819). The stability of agronomic parameters was represented by the coefficient of variation (CV). The respective CVs of yield in Z-17, Z-819, Z-39, and L-268 were 10.2%, 10.1%, 4.5%, and 5.7% in 2021 and 19.7%, 15.0%, 5.4%, and 6.5% in 2022. The respective CVs of grain weight were 6.3%, 5.7%, 3.4%, and 4.5% in Z-17, Z-819, Z-39, and L-268 in 2021, and 8.1%, 6.3%, 1.5%, and 0.8% in 2022. The mean source capacity per spikelet and pre-heading non-structural carbohydrate reserves per spikelet (NSCpre) were 7%–43% and 7%–72% lower in Z-819 and Z-17 than in L-268 and Z-39 in 2021 and 2022. The mean quantum yield of photosystem II photochemistry of leaf, leaf area index, and specific leaf weight of L-268 and Z-39 were higher than those of Z-819 and Z-17 at the heading stage. This study suggests that high NSCpre, caused by great leaf traits before heading, increases source capacity per spikelet and its stability, thereby increasing the stability of grain weight and yield. Increasing NSCpre is critical for achieving grain weight and yield stability in short-growth duration rice.

Production potential of short duration rice (Oryza sativa) in relation to age of seedlings, date of transplanting and crop geometry

An experiment was conducted at the research farm of Punjab Agricultural University, Ludhiana, Punjab during 2018 and 2019 to determine the production potential of rice (Oryza sativa L.) in relation to age of seedlings, date of transplanting and crop geometry. The results revealed that growth and productivity of short duration rice crop were improved by transplanting younger seedlings of 3 and 4 weeks age (nursery sown on June 12 and June 19) as compared to the older ones 5 and 6 week old seedlings (nursery sown on May 29 and June 5). Transplanting of rice at 25th June and 10th July with 20 cm × 15 cm crop geometry recorded better growth, yield attributes and higher yield as compared to 15 cm × 15 cm crop geometry. Rice transplanted on 10th July required fewer irrigations (14 and 17) as compared to the crop transplanted on June 25 (16, 19) in 2018 and 2019, respectively. This led to a water saving of 12.5 and 10.5% during those respective years, without compromising the yield. It is worth noting that a single irrigation was applied at a depth of 7.5 cm. For higher saving in irrigation water, nursery of PR 126 can be sown up to June 20 and 25–30 days old seedlings can be transplanted up to July 10 at 20 cm ×15 cm spacing.

Performance of Rice Varieties with Varying Irrigation Scheduling under Aerobic Condition

A field experiment was conducted at the Regional Research Technology and Transfer Station (RRTTS), Chiplima, Sambalpur, Odisha during summer season of 2019 &amp; 2020 to evaluate performance of medium duration rice varieties with varying irrigation schedules under aerobic condition. The experiment was laid out in split-plot design with 3 replications and consisted of four irrigation schedules i.e. I1 = Irrigation at IW/CPE = 1.0, I2 = Irrigation at IW/CPE = 1.5, I3 = Irrigation at IW/CPE = 2.0, and I4 = Irrigation at IW/CPE = 2.5 in main plot treatments and four varieties i.e. V1 = Naveen, V2 = MTU-1010, V3= CR Dhan-201 and V4 = CR Dhan-204 in subplot treatments. The result of pooled mean of both the years showed that higher grain yield was recorded at IW/CPE = 2.5 i.e. 4.07 t/ha , which was at par with IW/CPE = 2.0 (3.90 t/ha) and significantly superior to rest of other irrigation schedules. But in case of cultivars, higher grain yield was obtained with variety CR-Dhan 201(3.54 t/ha) which was at par with variety Naveen (3.30t/ha) and significantly superior to rest of other cultivars. The interaction of irrigation at IW/CPE 2.0 with variety CR Dhan 201 gave the highest grain yield (4.39t/ha) which was at par with irrigation at IW/CPE 2.5 with variety CR Dhan 201 (4.30 t/ha) and significantly superior to rest of other interactions. The interaction of irrigation schedules at IW/CPE 1.5 with Naveen variety produced the highest field water use efficiency (44.05 kg ha-cm-1) but it was at par with all irrigation schedules except at IW/CPE 2.5 with variety CR Dhan 201. Hence, it may be concluded that variety like CR Dhan 201 needs to be irrigated at IW/CPE 2.0 produced economically optimum yield and field water use efficiency on sandy loam soils of western region of Odisha under aerobic condition.

Weed management with Triafamone herbicide in transplanted rice ecosystem

Field experiments were conducted during Rabi 2018-19 (September to January) and Kharif 2019 (May to September). Medium duration rice cv. CO(R) 51 was used as a test variety at Tamil Nadu Agricultural University, Coimbatore, India to study the effect of Triafamone on broad spectrum weed control in transplanted rice. Triafamone was applied at two times. First set of treatments (30, 40,50 and 100 g/ha) applied two to three leaf stage of weeds and second set treatments imposed (30, 40,50 and 100 g/ha) at three days after transplanting of the rice crop. These treatments were compared with Pyrazosulfuron ethy 10% WP @ 15 g/ha, Pretilachlor 5% EC @ 750 g/ha, hand weeding @ 20 and 40 days after transplanting and unweeded control. The major grasses were Echinochloa crus-galli (L.) and E. colonum (L.) while the sedge weed included Cyperus nutans (L.). Among the broad leaved weeds Eclipta alba (L.) and Bergia ammanioides were the dominant species. In both the seasons of the study, lesser population of grass was recorded with the pre and early post emergence application of triafamone herbicide 40 g a.i. ha-1 (1.41 and 1.41 per m-2 at 28 and 42 DAA for both the seasons respectively) and it was closely followed by application of triafamone herbicide 50 g a.i. ha-1 and application of PE Pretilachlor at 0.75 kg a.i. ha-1 and EPOE Pyrazosulfuron ethyl at 15 g a.i. ha-1. The same trend was observed for broad leaved weeds and their weed dry weights. Application of triafamone herbicide at 40 g a.i. ha-1 as pre emergence and early post emergence application recorded highest weed control efficiency of 100, 97.7 and 99.6 % and 97.8% at 42 DAA during both years of experimentation and also resulted in higher grain yield (8052 and 8182 kg ha-1 during rabi 2018-19 and 9018, 9175 kg ha-1 during Kharif 2019). Further, it is noticed that, there was no residual toxicity of herbicide to the succeeding crops. Hence, application of Triafamone 40 g a.i. ha-1 either pre or early post emergence herbicide has higher productivity and no residues in transplanted rice ecosystem.&#x0D; Key words: Triafamone, efficacy, weeds and transplanted rice ecosystem

Effect of organic foliar nutrients on the growth and yield of rice (Oryza sativa)

Green revolution technologies played an important role in alleviating hunger but had adverse effects on natural resources. Our Indian agriculture completely transformed from begging bowl to self-sufficiency in food grain production with high yielding varieties supported by judicious inorganic fertilizers. In addition to that we have crossed the self-sufficiency level and focusing more on speciality agriculture. But at the same time, we forgot practising and recycling the organic manures which sustained the soil health and quality of produce. For a better yield achievement, combination of organic foliar nutrition will help in management of input practices. Therefore, a field experiment was conducted at the Agronomy Experimental Farm, Annamalai University during Kuruvai season in 2021 to evaluate the effect of organic foliar nutrients on growth and yield of rice. The experiment was laid out in randomized block design with nine treatments and replicated thrice. The treatment consisted of amirthakaraisal, panchagavya, vermiwash, fish amino acid, sea weed extract, humic acid, gibberellic acid and jeevamritham with different concentration along with recommended dose of fertilizer (RDF). Short duration rice variety ADT-43 was used as test variety. The foliar spray was done at active tillering and panicle premordial initiation stage. Among the treatments tried out, RDF+Jeevamritham at 3% recorded the maximum plant height (114.70 cm), leaf area index (6.14), number of panicles/m2 (396), number of filled grains/panicle (102.67), grain yield (5752 kg/ha) and straw yield (7953 kg/ha). Therefore, it can be suggested as a substitute source of nutrients for the growth and yield of rice.

Assessment of genetic variability and diversity analysis in medium duration rice accessions

Assessment of genetic variability and diversity analysis in medium duration rice accessions