Regional Agricultural Research Station Research Articles

Impact of Fertility Levels and Biofertilizers on Chickpea Yield, Soil Fertility and Economic Returns

A field experiment was conducted for two rabi seasons (2019-20 & 2020-21) at Regional Agricultural Research Station, Nandyala, Andhra Pradesh to study biofertilizers of PSB and inorganic fetilizers on growth, yield and quality Chickpea crop for Kurnool district of Andhra Pradesh. Afetr two years of the study, Significantly highest available soil Nitrogen (188 kg ha-1), Phosphorous (66.9 kg ha-1) and Potassium (484 kg ha-1) were recorded in treatment T8 (100% RDF + PSB in liquid form). Significantly highest chickpea yield of 2156 kg ha-1 was recorded with T8 (100% RDF + PSB (liquid form), the lowest yield was recorded with control (1839 kg ha-1). However, this treatment yielded results comparable to all treatments except the control during the two rabi seasons of 2019-20 and 2020-21. The economic evaluation of biofertilizers and chemical fertilizers application in chickpea crop revealed that maximum net returns (Rs 1,02,675) and higher B: C ratio (3.45) were obtained with application of 50% RDF plus PSB application. The present study was done to study to evaluate the influence of bio fertilizers on growth and yield of chickpea.

Assessment of Character Association in Pole Type French Bean (Phaseolus vulgaris L.) Genotypes

The present investigation was carried out at Regional Agricultural Research Station (RARS), Vijayapura during Rabi 2022-23. The experiment was laid out in Randomized Complete Block Design (RCBD) with two replications. To study the association studies in 32 pole type French bean genotypes. The correlation studies revealed that pod yield per plant was found positively and significantly associated with number of pods per plant (rg=0.668 and rp=0.620), pod length (rg= 0.526 and rp =0.431), average 10 pod weight (rg= 0.657 and rp = 0.660), number of pods per cluster (rg=0.373 and rp= 0.344) and number of clusters per plant (rg =0.365 and rp= 0.345) at both genotypic and phenotypic level. The direct selection for these traits would be rewarding for improvement of pod yield per plant in pole type French bean.

Evaluation of Genotypes against Water Stress and Salinity in Rice (Oryza sativa L.)

Abiotic stresses pose significant challenges to growth, yield and productivity thus threatening food security. Hence, it is essential to develop climate resilient rice varieties that mitigate the impact of abiotic stress. A study on physiological characterization for water and salinity stress was conducted in twenty-eight rice genotypes during kharif 2023 at Regional Agricultural Research Station, Maruteru. Among all the treatments, root length, shoot length, root and shoot dry weight and chlorophyll content was maximum under control followed by 1% mannitol, 2% mannitol and salinity stress. Visual scoring for water stress at seedling stage revealed that under mild water stress (1% M) more than 90% of plants survived in genotypes viz., AC-35678, FL 478, Ravana, Rahaspunjar, AUS 63, AUS 73, Vandana, NICRA 16, NICRA 17, CR-3439-4-E-17-2-1-B-1-S-1, CR-4215-2-5-2-M-4-SUB-2-5-1. Under severe water stress (2% M) more than 70% of the seedlings survived in NICRA 16, CR-4215-2-5-2-M-4-SUB-2-5-1, CRAC-4423-3, IET -18727, IC-516 149, IET-18716, AC-35678, FL 478, AC 85, Rahaspunjar, AUS 100, NICRA 17, CR-3439-4-E-17-2-1-B-1-S-1. Under salinity stress the score 3 was recorded in FL 478, and 5 in Rahaspunjar, IET -18727, NICRA 16, Ravana, NICRA 17. For both combined stresses, FL 478, Rahaspunjar, NICRA 16 and NICRA 17 were identified as tolerant and can be identified as donors for development of rice varieties having climate resilience.

Molecular Confirmation for Gall Midge (Biotype 3) Resistance in Phenotypically Resistant Rice Genotypes Using Functional Markers

This study performed molecular screening of rice genotypes, which showed no gall infestation in field conditions at the Regional Agricultural Research Station (RARS), Jagtial, during rabi, 2021-22. using functional markers such as “gm3del3” for the gm3 gene, “LRR del” for the Gm4 gene, and “PRP” for the Gm8 gene, six genotypes were analyzed. WGL-1145 contained all three resistance genes (gm3, Gm4, and Gm8). Additionally, three genotypes namely WGL-1147, WGL-1127, and Kakai had the Gm4 and Gm8 genes, while RP-5332-54-11-8-2-13 had only Gm8 and IR72476-B-P-9-3-1-1 possessed only gm3. These findings contribute to developing new rice varieties with resistance to gall midge, which can improve crop yields and food security in affected regions. Some promising rice varieties may be used as donors in breeding programs aimed at creating pyramided lines with durable gall midge resistance.

Positive Effects of Growth Retardants on Castor (Ricinus communis L.)

The perennial growth habit of castor plants (Ricinus communis L.) limits mechanical harvest because the plant grows very tall, when the environmental conditions are favorable and produces green flush interfering with mechanical harvesting. In order to prevent excessive growth plant growth, retardant are applied to modifying crop architecture. Present investigation was designed to study the effect of growth retardants on growth and yield parameters. The experiment was conducted at the regional agricultural research station, Palem farm of Professor Jayashankar Telangana Agricultural University, Nagarkurnool district, Telangana, taking locally available tall variety PCH-111. The experiment was laid out in Randomized Block Design with three replicates in Kharif, 2019. Treatments comprises of water spray, ethrel@500 ppm, ethrel@1000 ppm, CCC@1.5ml/lit, CCC@2.0 ml/lit and CCC@2.5 ml/lit and sprayings were done at expanding leaf in the 6th node of the primary stem, expanding leaf on the 8th node of the primary stem, appearance of the first inflorescence, one expanding leaf in a secondary stem after the appearance of the first inflorescence, and appearance of the second inflorescence. Results revealed that, plant growth retardants are effective in reducing plant height, whereas no spray recorded significant superior value for plant height (70.73 cm). For leaf number, there is no much deviations though ethrel treatment enhanced senescence in older leaves, newly developed leaves compensated the number but there was reduction in LAI, which were 1.70 and 2.18, respectively, in ethrel spray of 1000 ppm and 500 ppm. The yield reduction is lower in ethrel treatment due to lower capsule formation and lower spike length at higher concentration of ethrel. Hence, it is concluded that, retardant accelerates natural senescence and thus, acting as defoliants overcoming difficulties in mechanical harvesting.

Comparative Bio Assay of New Generation Insecticides against Invasive Southeast Asian Thrips, Thrips parvispinus (Karny) (Thripidae:Thysanoptera)

Aims: Management of invasive southeast Asian thrips, Thrips parvispinus under laboratory conditions. Study Design: Completely Randomized Design. Place and Duration of Study: Regional Agricultural Research Station, Guntur, Andhra Pradesh during 2023. Methodology: Bio assays study was conducted with eleven insecticides for the Management of Thrips parvispinus under laboratory conditions following leaf dip method replicated thrice. Mortality and corrected mortality were assessed at 24 and 48 hours after treatment imposition by counting the number of dead and live adults. Results: Bio assay study revealed that the insecticide broflanilide 300 DC @ 64.0 ml/ha recorded significant high percent mortality of 93.3 at 48 hours after exposure. The insecticides fluxametamide 10 EC @ 400 ml/ha, tolfenpyrad 15 EC@ 1000 ml/ha, spinoterom 11.7 SC @ 500 ml/ ha and fipronil 5 SC @1000 ml/ha were at par with broflanilide 300 DC with 90.0, 90.0, 86.7 and 86.7 percent mortality, respectively. Lowest mortality of 6.0 percent was observed in untreated control where the leaves were agitated in distilled water. The corrected mortality was calculated and the insecticides broflanilide 300 DC (92.59 %), fluxametamide 10 EC (88.9), tolfenpyrad 15 EC (89.3), spinetoram 11.7 SC (85.9) and fipronil 5 SC @400 ml/acre (85.2) recorded high corrected mortality at 48 hours of post treatment.

Impact of Mid-season Moisture Stress on Yield Attributes and Seed Quality in Groundnut Genotypes

A field experiment was conducted at Regional Agricultural Research Station, Tirupati, Acharya N.G. Ranga Agricultural University during rabi, 2022 and 2023 to study the impact of mid-season moisture stress (40-80 DAS) on yield attributes and quality traits of groundnut genotypes. The experiment was carried out in randomized block design with factorial concept with two main treatments i.e., control and mid-season moisture stress (40-80 DAS) and 12 sub treatments i.e., two check varieties and ten contrasting groundnut genotypes in three replications. Among the groundnut genotypes and check varieties tested for their tolerance to moisture stress the genotypes, TCGS 2326, TCGS 1792, K9 and TCGS 2333 were found to withstand mid-season moisture stress and maintained highest 100 kernel weight, shelling percentage, protein and oil content indicating tolerance to moisture stress.

Genetic variability, diversity and principal component analysis in B and R lines of rabi sorghum [Sorghum bicolor (L.) Moench

Hybrid technology is exploited in kharif (rainy) sorghum while the same is not the scenario in Rabi sorghum which is still dominated by landraces and varieties which have poor yield potentiality. Considering the necessity of development of heterotic hybrids, an attempt was made to screen hybrid parents (B and R lines) to assess variability and genetic diversity, for productivity traits. The study was conducted with 32 B and R lines at Regional Agricultural Research Station, Vijayapur during 2021-22. PCV was observed to surpass GCV across all traits. The traits grain yield per plant, fodder yield per plant, grain number per plant, and harvest index exhibited notably high PCV and GCV. Plant height, panicle length, panicle harvest index, and harvest index recorded high heritability and genetic advance, suggesting their control by additive gene action and potential for improvement via selection. Cluster analysis classified the 32 genotypes into four groups. PCA condensed 14 traits into five principal components, capturing 81.50% of total variation. The genotypes remained scattered in all four quadrants in PCA- Biplot, showing large genetic variability in quantitative traits studied. Keywords: Genetic variability, heritability, diversity, clusters, PCA and rabi sorghum

Effect of Different Kharif Paddy Straw Management Options and Different Levels of Nitrogen on Soil Dehydrogenase and Urease Activity

A field experiment was conducted during rabi 2020-21, at Regional Agricultural Research Station, Polasa, Jagtial, PJTSAU to study soil dehydrogenase and urease activity as influenced by different kharif paddy straw management options and nitrogen levels. The results reveal that dehydrogenase and urease activity of soil was significantly influenced by paddy straw management options and activity was increased with crop duration up to 60 DAT and decreased after harvest. Dehydrogenase activity was reduced after burning (1.93 mg TPF produced g-1 soil d-1) as compared to the initial values (2.34 mg TPF produced g-1 soil d-1). The highest dehydrogenase activity of 3.74 and 3.54 mg TPF produced g-1 soil d-1 was recorded at 60 DAT in paddy straw incorporation with phosphorus and incorporation without phosphorus and decreased to 3.36 and 3.03 mg TPF produced g-1 soil d-1 after harvest respectively. Soil urease activity was showed an increasing trend with crop duration up to 60 DAT and then declined. Maximum activity of 3.05, 4.84, 5.17 mg NH4+ released g-1 soil h-1 was observed at 60 DAT under paddy straw burning, paddy straw incorporation with phosphorus incorporation without phosphorus respectively. Paddy straw incorporation with phosphorus recorded higher urease activity and paddy straw burning recorded lower urease activity at all the intervals of crop growth. The effect of nitrogen levels on soil urease activity was found to be significant. Soil urease was highest with 120% RDN followed by 115% RDN, followed by 110% RDN, followed by 100% RDN and the similar trend was observed at all the intervals of crop growth.

Monitoring of Virulence of Gall Midge (Orseolia oryzae Wood-mason) Population on Rice

A study was conducted for two years during 2022 and 2023 at Regional Agricultural Research Station, Warangal, Telangana, India to know the virulence of gall midge on rice varieties with known gall midge resistant genes at Warangal. During both the years i.e., 2022 and 2023, the virulence of gall midge was low in Aganni followed by Akshayadhan, W1263 and Purple. The gall midge virulence was very low and similar in Aganni and Akshayadhan which reveals the efficacy of gall midge resistance genes i.e., Gm4 and Gm8 against gall midge biotype 4M at Warangal. Since Purple variety does not have any gall midge resistant genes, gall midge virulence was highest on Purple variety. The study revealed that, gall midge genes viz., Gm4 and Gm8 are holding good for resistance against gall midge biotype 4M in both the years of study. However, a close monitoring of the virulence pattern in endemic areas is important for deployment of effective genes in developing resistant varieties.

Seed Yield and Quality of Wheat as Influenced by Different Agronomic Practices in South-Central Coastal Region (Aez-13) of Bangladesh

A field study was carried out at Regional Agricultural Research Station, Rahmatpur, Barishal during Rabi 2019-2020 on wheat seed yield and quality influenced by different management practices. The experiment was comprised of two sowing dates with seven different agronomic management practices. The experiment was laid out in split plot design where sowing dates were assigned in main plot and different agronomic management practices in sub-plot with three replications. The results revealed that, optimum sowing condition (20th November) always maintain superiority over delayed sown condition (20th December) in respect of seed yield and quality. From agronomic management aspects strip tillage + recommended fertilizer doses+ 3 irrigations showed the best permormance in respect of seed yield (3.433 t/ha) and quality. From interaction effects of sowing date × agronomic management practices using strip tillage + recommended fertilizer doses+ 3 irrigations treatment with optimum sowing condition e.g. 20th November sowing condition performed the best in respect of seed yield (4.223 t/ha) and quality. Another two treatments (Strip tillage + recommended fertilizer dose + Boron foliar spray at anthesis (0.2%) + 2 irrigations (CRI, Booting) + Cowdung) and (Recommended fertilizer dose (NPKSMgZnB@ 120-30-90-15-6-2.6-1 kg/ha) + Boron foliar spray at anthesis (0.2%) + 3 irrigations (CRI, Booting, Grain filling) also produced statistically identical seed yield (4.15 and 4.01 t/ha, respectively). But considering economic point of view, (Recommended fertilizer dose + 0.2% boron foliar spray at anthesis + 3 irrigations) gave the highest BCR (2.46) and economic return. In late seeding condition (20th December) (strip tillage + recommended fertilizer doses+ 3 irrigations) treatment had performed the best in respect of seed yield (2.643 t/ha) and seed quality (germination 67.33%). J. Bio-Sci. 32(2): 01-12, 2024

Phenotypic Screening of Rice Cultures for Resistance against Brown Plant Hopper (Nilaparvata lugens Stal) at Warangal, India

Brown planthopper (BPH), Nilaparvatalugens Stal (Homoptera: Delphacidae), is one of the most destructive insect pests causing significant yield losses in rice production. During Kharif, 2021, a set of 91 rice cultures were screened against brown plant hopper (BPH) through standard seed box technique in screen house at Regional Agricultural Research Station, Warangal. Resistant checks RP 2068-18-3-5 recorded Damage Score (DS) of <3, Mo-1 recorded DS of 3.67, PTB 33 recorded DS of 3.29. Mean damage score was 8.94 in the susceptible check Taichung Native 1(TN-1) against BPH. The 2 entries viz., RPGP-1066-36-12-1-2 and WS-18-OYT-72/BPH were found to be highly resistant to BPH. RPGP-1386-3-1-1-1 was found to be resistant to BPH. 5 entries viz., BPT 3025, RPGP-1011-100-56-1-4-1, RPGP-2212-8-1-2-2, KNM 12505 and WS-18-AYT-10/BPH were found to be moderately resistant to BPH. Cultivation of resistant cultures will reduce the cost of plant protection against BPH in addition to protection of natural enemies and environment. The rice cultures exhibiting resistance against BPH may be helpful in crossing programmes to develop BPH resistant varieties which shall be used in IPM as a component.

Performance of Zero Tillage Safflower (Carthamus tinctorius L.) under Different Irrigation Schedules and Nutrient Levels in Northern Telangana Zone (NTZ)

An experiment was carried out at Regional Agricultural Research Station, Polasa, Jagtial in Northern Telangana Zone during rabi (winter season), 2023-2024 where the performance of zero tillage safflower (Carthamus tinctorius L.) was tested under different irrigation schedules and nutrient levels. The experiment was executed using a factorial randomized block design with 15 treatment combinations, with three replications. The treatments consisted of two factors i.e., factor-1 included irrigation schedules-; I1: Irrigation at rosette and flower initiation stages, I2: Irrigation at rosette and seed development stages, I3: Irrigation at branching and flower initiation stages, I4: Irrigation at branching and seed development stages and I5: No irrigation (residual moisture) and factor-2 included nutrient levels, S1: 75% Recommended dose of fertilizer (RDF), S2: 100% RDF and S3: 125% RDF. The results revealed that irrigation at branching and seed development stages(I4) reported significantly highest seed (1199 kg ha-1), stalk yield (4724 kg ha-1) and yield attributing traits viz.; number of heads plant-1(22.5), number of seeds head-1(23.4), seed weight plant-1(19.8 g), 100-seed weight (7 g), whereas the lowest yield were observed with no irrigation (residual moisture) (I5) treatment. Among different nutrient levels, application of 125% RDF (S3) resulted in the highest seed (1105 kg ha-1) and stalk yield (4429 kg ha-1) and yield attributing traits viz.; number of heads plant-1(21.4), number of seeds head-1(22.6), seed weight plant-1(19.5 g), 100-seed weight (6.7 g) over 75% RDF (S1). Among different treatments, irrigation at the branching and seed development stages combined with the application of 125% RDF gave the best results.

Assessment of Yield Losses due to Major Insect Pests in Sesame

Yield losses due to major insect pests viz., leaf webber and capsule borer Antigastra catalaunalis (Duponchel) and gall fly Asphondylia sesami (Felt) in promising sesame varieties was carried out at the Regional Agricultural Research Station, Jagtial, during summer, 2019 and 2020 under protected and unprotected conditions. The highest % avoidable yield losses was recorded in Hima variety (35.45) followed by Swetha, Sharada, GT 10, Madhavi, Gouri, VRI 1 and Rajeswari with 34.27, 33.17, 32.48, 31.05, 30.53, 30.01 and 29.75, respectively. Regarding cost benefit ratio, highest was recorded in Hima variety (1:2.23) followed by Swetha (1:2.05) and Sharada (1:1.75).

Genetic Variability Studies for Morpho-Physiological and Yield-attributing Traits in Foxtail Millet (Setaria italica L. Beauv.)

Foxtail millet is an underutilized crop which has high nutritional values and wide genetic resources, possessing the ability to tolerate several abiotic stresses efficiently. Those resources must be used in order to improve desired traits, primarily yield attributes. This investigation was carried out to assess the genetic parameters, such as variability, per se performance, heritability and genetic advance as percent of mean (GAM) for sixteen morpho-physiological, yield-attributing traits in fifty foxtail millet germplasm accessions at the Regional Agricultural Research Station, Nandyal during Rabi, 2023-2024. The study revealed the wide range of variation for all studied traits and that the accessions SiA 3290, SiA 4345, and SiA 4391 had potential for most traits and a high grain yield per plant. Thus, after multilocation testing, these accessions might be exploited for commercial cultivation. The assessment revealed that the phenotypic coefficient of variation (PCV) was slightly greater than the corresponding genotypic coefficient of variation (GCV), indicating the influence of the environment on the manifestation of these traits. It was also observed that the traits viz.., photosynthetic rate, transpiration rate, stomatal conductance, abortive grain rate, and grain yield per plant had high PCV and GCV and these traits significantly contributed to the overall variability and scope for selection. High heritability in combination with high GAM was observed for photosynthetic rate, transpiration rate, stomatal conductance, 1000-grain weight, fodder yield per plant and grain yield per plant. This indicates that, these traits are mostly governed by additive genes and thus making them suitable for simple direct selection to improve these traits and further breeding efforts focused on increasing yields.

Genetic Validation of Advanced Backcross-derived Rice Lines for Nilaparvata lugens (Stal) Resistance via SSR Markers

Nilaparvata lugens (Stål), referred to as the brown planthopper (BPH), is a serious threat to paddy cultivation. It inflicts damage by feeding on rice plants and serves as a vector for the rice ragged stunt virus and the rice grassy stunt virus, both of which contribute to significant yield losses. The research was conducted during kharif-2021 at Regional Agricultural Research Station (RARS), Warangal. SSR markers RM 3766 (for the Bph3 gene) and RM 586 (for the Bph4 gene) were used for molecular confirmation of resistance in BPH. The study revealed the presence of resistance genes in all resistant and moderately resistant lines, except Siddhi-BC2F6 BPH-BL-24, which was heterozygous (partial resistance) for Bph3, and Siddhi-BC2F6 BPH-BL-11 and Siddhi-BC2F6 BPH-BL-52, which were heterozygous (partial resistance) for Bph4. This genetic validation using SSR markers not only confirms the successful introgression of resistance traits but also enhances the efficiency of breeding programs aimed at developing durable BPH-resistant rice cultivars.

Impact of Different Plant Densities and Fertilizer Levels on Yield Attributes, Yield and Fibre Quality Characters of Bt Cotton in HDPS

Adopting a high-density planting system in cotton cultivation has resulted in increased yields compared to traditional methods. Despite the clear benefits, farmers face various challenges throughout the cultivation process, from sowing to harvesting. However, selecting appropriate plant spacings, fertilizer levels and implementing tailored cultivation techniques can significantly enhance productivity. A field experiment was conducted at Siddapur research farm, Regional Agricultural Research Station, Warangal, Telangana, India during kharif 2023 to investigate the “Impact of different plant densities and fertilizer levels on yield attributes, yield and fibre quality characters of cotton in high density planting system (HDPS)”. The experiment was laid out in randomized block design (factorial) and replicated thrice, consisting of 12 treatment combinations comprising of three plant spacings S1: 80 x 20 cm (62,500 plants ha-1), S2: 90 x 15 cm (74,074 plants ha-1), S3: 90 x 60 cm in factor I and four fertilizer levels (F1: 100%RDF, F2: 125%RDF, F3: 100%RDF + Microbial consortia, F4: Control) in factor II. Both the factors significantly influenced the number of bolls per plant, number of bolls m-2 and seed cotton yield per hectare. The results revealed that higher no. of bolls plant-1 were recorded in 90 x 60 cm (18,518 plants ha-1) however, higher no. of bolls m-2, seed cotton yield (2233 kgha-1) obtained from higher plant density (74,074 plants ha-1) with the spacing 90 x 15 cm. Boll weight was not significantly influenced by varied plant spacings and fertilizer levels. Among the different levels of fertilizer, 125%RDF recorded highest no. of bolls per plant, no. of bolls m-2 and seed cotton yield (2362 kgha-1). Fibre quality characters viz., Upper half mean length(mm), micronaire(µginch-1), tenacity(gtex-1) and uniformity index (%) were not significantly influenced by both plant spacings and fertilizer levels as they are primarily governed by genetic makeup of cotton genotypes. For optimum seed cotton yield, cotton should be sown at closer spacing 90 x 15 cm and the application of 125%RDF was economically feasible in high density planting system.

Development of High Yielding Deep Water Rice Variety MTU 1184 Suitable for Semi-Deep Flooded Ecosystem of South Eastern Region of India

In recent years due to heavy and intense rainfall and cyclonic storms, paddy crop is experiencing damage due to flooding. If the flood water stagnation remains for more than a week the varieties are unable to sustain and there by the yield levels are drastically reduced. Hence, there is a need to develop submergence tolerant variety to minimize the yield losses. Acharya NG Ranga Agricultural University (ANGRAU), Regional Agricultural Research Station, Maruteru has developed flood tolerant variety MTU 1184 through conventional plant breeding using PLA 1100 and BM 71 as parents. The flood tolerant rice culture was extensively evaluated for yield in semi deep water ecosystem at RARS, Maruteru over the years of kharif, 2012 to kharif, 2016 in Station yield trials. The variety recorded superior grain yield (4370 kg/ha) against check PLA 1100 (3811 kg/ha) and yield advantage over check was 14.67%. The entry was tested in AICRIP trials from 2014 to 2017 at RARS, Maruteru and the results revealed that MTU 1184 registered 4650 kg/ha and found to be significantly superior over the national check, Sabitha (3703 kg/ha) and the per cent increase over check was 25.57. The variety recorded a mean grain yield of 4281 kg/ha and found to be significantly superior over the national check, Sabitha (3011 kg/ha) and yield advantage was 1270 kg/ha and per cent increase over national check was 42.17 and zonal check Poornendu in 8 locations of six states of south eastern region. Multi location testing of the variety from 2015 to 2017 revealed that the variety has out yielded (5370 kg/ha) and found superior over the best check PLA 1100 (4290 kg/ha) and the per cent increase over check was 25.18. Minikit testing in 890 locations for a period of three years from 2016 to 2018 revealed that the average mean yield of the variety over three years was 6039 kg/ha against local popular check PLA 1100 (5700 kg/ha) and per cent increase over check was 6.0 when tested in Andhra Pradesh.

Evaluating the Influence of Different Agronomic Strategies on the Growth and Development of Maize (Zea mays L.) Grown in Rice Fallows of Northern Telangana Zone

Aims: To study the changes in plant height, dry matter production, leaf area and plant population under different tillage practices, irrigation and nitrogen levels in rice fallow maize. Study Design: Split- split plot design. Place and Duration of Study: Regional Agricultural Research Station farm, Polasa, Jagtial during rabi 2022-23 and 2023-24. Methodology: The experiment was laid out in split- split plot design with twelve treatment combinations that includes 2 main plot, 3 sub plot and 2 sub-sub plot treatments which are replicated thrice. The treatments are as follows: Main plots: T1- Zero tillage, T2- Conventional tillage (tillage with cultivator twice fb rotovator twice); Sub plots: I1- Irrigation at 60% ASM, I2- Irrigation at 40% ASM and I3- Irrigation at six critical stages; and Sub-sub plot treatments: N1- 100% RDN (240 kg ha-1) and N2- 120% RDN (288 kg ha-1). Results: Results indicated that highest mean plant height was recorded in conventional tillage (65.8, 204.4 & 210.9 cm) and in N2 treatment (64.6, 201.3 & 207.6 cm) during sixth leaf, silking and physiological maturity respectively. Irrigations showed non-significant effect during sixth leaf and during other two stages I3 treatment has recorded higher plant height (200.1 & 206.6 cm). Similar results were obtained in case of leaf area. The mean dry weight was also higher in conventional tillage (17915 kg ha-1), I3 treatment (16789 kg ha-1) and N2 (16418 kg ha-1). The initial plant population was higher in conventional tillage (7.2 plants m-2) than that of zero tillage and irrigation & nitrogen levels has no effect on population. Conclusion: All the growth parameters were significantly affected by tillage, irrigation and nitrogen levels at all the stages except the influence of irrigation on plant height at sixth leaf stage. Plant population was significantly affected by tillage but non-significant effect was recorded by irrigation an nitrogen levels. Interaction was found between irrigation and nitrogen levels in-case of dry matter production.

Growth Response and Economics Variability in Hybrid Pigeonpea to Nitrogen and Phosphorus Fertilization

Aims: To study the growth response and economic variability in hybrid pigeonpea to nitrogen and phosphorus fertilization. Study Design: Factorial randomized block design. Place and Duration of Study: A field experiment was conducted on deep black cotton soils of Regional Agricultural Research Station, Lam during kharif season, 2018-19 in hybrid pigeonpea (ICPH-2740). Methodology: The experiment was laid out in factorial randomized block design (FRBD) comprised of four levels of nitrogen in first factor (N1: 20 kg ha-1, N2: 40 kg ha-1, N3: 60 kg ha-1, N4: 80 kg ha-1) and three levels of phosphorus allotted to second factor (P2O5) (P1: 50 kg ha-1, P2: 75 kg ha-1, P3: 100 kg ha-1). Results: The higher values of grain yield (1900 kg ha-1 & 1833 kg ha-1), net returns (Rs.60522/- & Rs.57181/-) and B:C ratio (1.62 & 1.54) were found with application of nitrogen (60 kg ha-1) and phosphorus (75 kg ha-1), respectively. Conclusion: It was concluded that in Krishna agro-climatic zone of Andhra Pradesh, an application of 60 kg N ha-1 and 75 kg P2O5 ha-1 was applied for getting economically higher grain yield in hybrid pigeonpea.